Water Quality of the Lower Columbia River Basin:

Analysis of Current and Historical Water-Quality D

through 1994

U.S. GEOLOGICAL SURVEY

Water-Resources Investigations Report 95-4294

Prepared in cooperation with the

Lower Columbia River Bi-State

Water-Quality Program
Water Quality of the Lower Columbia River Basin:

Analysis of Current and Historical Water-Quality D

through 1994

By Gregory J. Fuhrer, Dwight Q. Tanner, Jennifer L. Morace,

Stuart W. McKenzie, and Kenneth A. Skach

U.S. GEOLOGICAL SURVEY

Water-Resources Investigations Report 95–4294

Prepared in cooperation with the

Lower Columbia River Bi-State

Water-Quality Programs

Portland, Oregon

1996
U. S. DEPARTMENT OF THE INTERIOR

BRUCE BABBITT, Secretary

U.S. GEOLOGICAL SURVEY

Gordon P. Eaton, Director

The use of trade, product, or firm names in this publication is for descriptive

purposes only and does not imply endorsement by the U.S. Government.

Copies of this report can be

purchased from:

U.S. Geological Survey

Earth Science Information C

Open-File Reports Section

Box 25286, MS 517

Denver Federal Center

Denver, CO 80225

For additional information

write to:

District Chief

U.S. Geological Survey, WRD

10615 S.E. Cherry Blossom Drive

Portland, Oregon 97216
iii

FOREWORD

One of the great challenges faced by the Nation’s water-resource scientists

is providing reliable water-quality information to guide the management and

protection of our water resources. That challenge is being addressed by Federal,

Tribal, State, interstate, and local water-resources agencies, by academic institutions, and by private industry. Many of these organizations are collecting

water-quality data for a host of purposes, including compliance with permits

and water-supply standards, development of remediation plans for specific

contamination problems, decision of operational procedures for industrial,

wastewater, or water-supply facilities, and refinement of research to advance

our understanding of water-quality processes. In fact, during the past two decades,

tens of billions of dollars have been spent on water-quality data collection

programs. Unfortunately, the utility of these data for present and future regional

and national assessments is limited by such factors as the areal extent of the sampling network, the frequency of sample collection, the variety of collection and

analytical procedures, and the types of water-quality characteristics determined.

The Lower Columbia River Bi-State Water Quality Program, with

involvement from private industry, sports and commercial fishing, public ports,

environmental groups, municipal, State, Northwest Power Planning Council, and

Federal interests, has provided guidance to:

1. Provide a regionally consistent description of water-quality conditions;

2. Define seasonal and long-term trends (or lack of trends) in water quality; and

3. Identify, describe, and explain, as possible, the major factors that affect

observed water-quality conditions and trends.

Don Yon, Project Manager

Lower Columbia River Bi-State Water Quality Program
iv
v

CONTENTS

Foreword ..........................................................................................................................................................................

Abstract ............................................................................................................................................................................

Introduction......................................................................................................................................................................

Background .............................................................................................................................................................

Purpose and Scope ..................................................................................................................................................

Acknowledgments...................................................................................................................................................

The Lower Columbia River Basin ...................................................................................................................................

Precipitation ............................................................................................................................................................

Streamflow Conditions ...........................................................................................................................................

Land and Water Use................................................................................................................................................

Point Source ............................................................................................................................................................

Data Sources and Methods of Analysis ...........................................................................................................................

Current and Historical Sources of Data ..................................................................................................................

Historical Data ...............................................................................................................................................

Current Data...................................................................................................................................................

U.S. Geological Survey.........................................................................................................................

Washington Department of Ecology.....................................................................................................

Oregon Department of Environmental Quality.....................................................................................

Data-Analysis Methods...........................................................................................................................................

Loads..............................................................................................................................................................

Trends.............................................................................................................................................................

Existing Water-Quality Guidelines.........................................................................................................................

Ambient Stream Water Quality......................................................................................................................

Aquatic Life............................................................................................................................................

Human Health.........................................................................................................................................

Drinking-Water Quality .................................................................................................................................

Regulations.............................................................................................................................................

Health Advisories ...................................................................................................................................

Analysis of Available Surface-Water-Quality Data.........................................................................................................

Water Temperature .................................................................................................................................................

Dissolved Oxygen and pH ......................................................................................................................................

Total Dissolved Gas ................................................................................................................................................

Suspended Sediment ...............................................................................................................................................

Nutrients..................................................................................................................................................................

Major Ions and Related Measures...........................................................................................................................

Trace Elements........................................................................................................................................................

Organic Compounds ...............................................................................................................................................

Fecal-Indicator Bacteria..........................................................................................................................................

Radionuclides..........................................................................................................................................................

Quality Assurance ............................................................................................................................................................

Examples of Quality-Assurance Data .....................................................................................................................

Use of Quality-Assurance Data to Interpret Environmental Data ..........................................................................

Considerations for Future Data-Collection Activities .....................................................................................................

Summary ..........................................................................................................................................................................

References Cited ..............................................................................................................................................................

Supplemental Data Tables ...............................................................................................................................................
vi

FIGURES

1. – 2. Maps showing:

1. The Columbia River Basin..........................................................................................................................

2. The lower Columbia River Basin, Oregon and Washington ......................................................................

3. –37. Graphs showing:

3. Annual and mean annual precipitation at Bonneville Dam, Government Camp, Portland, Eugene,

Cougar, and Astoria, lower Columbia River Basin, Oregon and Washington, 1920–93 ...........................

4. Mean monthly precipitation at Portland, Cougar, and Eugene, lower Columbia River Basin,

Oregon and Washington .............................................................................................................................

5. Estimated monthly mean streamflow in the Columbia River at mouth near Astoria for the low-,

median-, and high-streamflow years, lower Columbia River Basin, Oregon .............................................

6. Annual mean streamflow and median annual streamflow for the Columbia River at mouth, 1928–84.....

7. Estimated monthly mean streamflow in the Columbia River at mouth near Astoria, 1967 water year,

and Columbia River at Beaver Army Terminal near Quincy, 1994 water year, lower Columbia River

Basin, Oregon and Washington ..................................................................................................................

8. Streamflows in the Willamette River at Portland and Columbia River at Warrendale, lower Columbia

River Basin, Oregon and Washington, 1994...............................................................................................

9. –12. Maps showing:

9. Land use and land cover by hydrologic units, lower Columbia River Basin, Oregon and Washington, 19

10. Point-source domestic discharges, lower Columbia River Basin, Oregon and Washington, 1994 ...........

11. Locations of point sources other than domestic discharge, lower Columbia River Basin, Oregon and

Washington, 1994 .......................................................................................................................................

12. Point-source discharges for chemical, seafood processing, and other miscellaneous facilities, lower

Columbia River Basin, Oregon and Washington, 1994..............................................................................

13. Graph showing number of historical surface-water-quality determinations by constituent group, lower

Columbia River Basin, Oregon and Washington, 1939–93 ...............................................................................

14. Map showing U.S. Geological Survey sampling locations, lower Columbia River Basin, Oregon and

Washington, 1994...............................................................................................................................................

15.–24. Graphs showing:

15. Distribution of daily mean water temperatures in the lower Columbia River Basin, Oregon and

Washington, 1968–94 water years ..............................................................................................................

16. Distribution of daily mean water temperatures in the Columbia River at Warrendale, Kalama, and

Bradwood and in the Willamette River at Portland, lower Columbia River Basin, Oregon and

Washington, 1975–92 .................................................................................................................................

17. Instantaneous water temperatures in the main stem and tributaries of the lower Columbia River

Basin, Oregon and Washington, July to September 1994...........................................................................

18. Distribution of dissolved-oxygen concentrations, lower Columbia River Basin, Oregon and

Washington, 1994 .......................................................................................................................................

19. Distribution of 1974–94 and 1994 dissolved-oxygen concentrations measured in the Columbia River

at Warrendale, lower Columbia River Basin, Oregon ................................................................................

20. Distribution of 1949–58, 1972–94, and 1994 dissolved-oxygen concentrations measured in the

Willamette River at Portland, lower Columbia River Basin, Oregon.........................................................

21. Distribution of 1960–74 and 1994 dissolved-oxygen concentrations measured in the Kalama River

above Spencer Creek near Kalama, lower Columbia River Basin, Washington ........................................

22. (a) pH in the main stem and tributaries of the lower Columbia River Basin and

(b) chlorophyll-a concentrations in relation to pH in the Columbia River at river mile 102,

downstream from Hayden Island, Oregon and Washington, 1994 .............................................................

23. Total dissolved-gas concentrations in the Columbia River at Warrendale, lower Columbia River Basin,

Oregon, 1984–93 and 1994.........................................................................................................................

24. Relation between daily mean streamflow and suspended-sediment concentrations in the Willamette

River at Portland and Columbia River at Warrendale, lower Columbia River Basin, Oregon, 1994 ........

25. Maps showing spatial distribution of 90th-percentile values for phosphorus concentrations in unfiltered wate

and nitrite plus nitrate and ammonia in filtered water by subbasin or unit, lower Columbia River Basin,

Oregon and Washington, 1964–93.....................................................................................................................
vii

26.–27. Graphs showing:

26. Concentrations of phosphorus in unfiltered water and nitrite plus nitrate in filtered water in the

Columbia River at Hayden Island, Willamette River at Portland, and Columbia River near

Columbia City, lower Columbia River Basin, Oregon and Washington, 1994 ..........................................

27. Monthly mean daily loads of ammonia and nitrite plus nitrate in filtered water and phosphorus in

unfiltered water in the Columbia River at Warrendale, Willamette River at Portland, and Columbia

River at Beaver Army Terminal, lower Columbia River Basin, Oregon and Washington, 1994...............

28. Map showing spatial distribution of 90th-percentile values for total dissolved solids by subbasin or unit,

lower Columbia River Basin, Oregon and Washington, 1947–93.....................................................................

29.–37. Graphs showing:

29. Major-ion composition in the Columbia River at Warrendale, Willamette River at Portland, and

Columbia River at Beaver Army Terminal, lower Columbia River Basin, Oregon and Washington,

1994.............................................................................................................................................................

30. Specific conductance in the main stem and tributaries during August and November, lower

Columbia River Basin, Oregon and Washington, 1994..............................................................................

31. Major-ion composition in the Columbia River near Columbia City, Willamette River at Portland, and

Multnomah Channel near mouth at St. Helens, lower Columbia River Basin, Oregon, 1994 ..................

32. Concentrations of silica in the Willamette River at Portland, Multnomah Channel near mouth at

St. Helens, and Columbia River near Columbia City, lower Columbia River Basin, Oregon, 1994 .........

33. Frequently detected organic compounds, lower Columbia River Basin, Oregon and Washington, 1994..

34. Frequency of detection for selected organic compounds in the lower Columbia River Basin, Oregon

and Washington, 1994.................................................................................................................................

35. Relation between daily mean streamflow and atrazine concentrations in filtered water in the

Willamette River at Portland, lower Columbia River Basin, Oregon, 1994...............................................

36. Atrazine concentrations in filtered water from November to December and from August to

September, lower Columbia River Basin, Oregon and Washington, 1994.................................................

37. Distribution of fecal-coliform bacteria concentrations in the Columbia River at Warrendale and

Willamette River at Portland, Oregon, 1976–94.........................................................................................

TABLES

1. Summary statistics for seasonal variations in streamflow at selected sites, lower Columbia River Basin,

Oregon and Washington, 1967 water year .........................................................................................................

2. Percentage of land in specific land-use and land-cover categories, lower Columbia River Basin, Oregon

and Washington, 1980........................................................................................................................................

3. Water use in the lower Columbia River Basin, Oregon and Washington, 1990 water year .............................

4. Inventory of point-source classifications, lower Columbia River Basin, Oregon and Washington .................

5. Hydrologic units included in historical data retrievals and subbasin units used for analysis of historical data,

lower Columbia River Basin, Oregon and Washington.....................................................................................

6. Sites that have the most water-quality determinations from 1939–93, lower Columbia River Basin,

Oregon and Washington.....................................................................................................................................

7. Sampling sites and constituents analyzed, lower Columbia River Basin, Oregon and Washington, 1994 .......

8. Method reporting limits for major ions, nutrients, organic carbon, and trace elements analyzed in filtered

and unfiltered water, lower Columbia River Basin, Oregon and Washington, 1994.........................................

9. Method detection limits for organic compounds analyzed in filtered water, lower Columbia River Basin,

Oregon and Washington, 1994...........................................................................................................................

10. Method reporting limits for trace elements analyzed in suspended sediment, lower Columbia River Basin,

Oregon and Washington, 1994...........................................................................................................................

11. Laboratory analytical methods and reporting limits for Washington Department of Ecology, lower

Columbia River Basin, 1994 ..............................................................................................................................

12. Amount of water quality data available for load estimation program, and mean 95-percent confidence

intervals for load estimates at three sites in the lower Columbia River Basin, Oregon and Washington..........

13. Water-quality sites that have continuous record of stream temperature, lower Columbia River Basin,

Oregon and Washington, 1968–94.....................................................................................................................
viii

14. Monthly distributions of daily mean water temperatures at selected sites, lower Columbia River Basin,

Oregon and Washington, 1969–92.....................................................................................................................

15. Signs of gas-bubble trauma in salmonids...........................................................................................................

16. Distribution of suspended-sediment and suspended-solids concentrations, lower Columbia River Basin,

Oregon and Washington, 1994...........................................................................................................................

17. Calculated monthly and annual mean daily loads for suspended sediment at selected sites, lower

Columbia River Basin, Oregon, 1994 ................................................................................................................

18. Calculated monthly and annual mean daily suspended-sediment loads for the current water year and

low-, median-, and high-streamflow water years in the Columbia River at Warrendale and Willamette

River at Portland, lower Columbia River Basin, Oregon...................................................................................

19. Comparison of nutrient concentrations in water in the lower Columbia River Basin to surface waters of

the United States.................................................................................................................................................

20. Distribution of nutrient concentrations in water, lower Columbia River Basin, Oregon and Washington,

1994....................................................................................................................................................................

21. Calculated monthly and annual mean daily nutrient loads for the current water year and low-, median-,

and high-streamflow water years in the Columbia River at Warrendale and Willamette River at Portland,

lower Columbia River Basin, Oregon ................................................................................................................

22. Calculated monthly and annual mean daily loads for ammonia and nitrite plus nitrate in filtered water

and phosphorus in unfiltered water at selected sites, lower Columbia River Basin, Oregon, 1994 ..................

23. Mass balances for streamflow and ammonia and nitrite-plus-nitrate loads in filtered water, lower

Columbia River Basin, Oregon and Washington, 1994 .....................................................................................

24. Mass balances for streamflow, phosphorus loads in unfiltered water, and suspended-sediment loads,

lower Columbia River Basin, Oregon and Washington, 1994...........................................................................

25. Distribution of major-ion concentrations in filtered and unfiltered water, lower Columbia River Basin,

Oregon and Washington, 1994...........................................................................................................................

26. Calculated monthly and annual mean daily loads for total dissolved solids at selected sites, lower

Columbia River Basin, Oregon, 1994 ................................................................................................................

27. Comparison of selected major- and trace-element concentrations in filtered water in the lower Columbia

River Basin to surface waters worldwide...........................................................................................................

28. Distribution of major- and trace-element concentrations in filtered water, lower Columbia River Basin,

Oregon and Washington, 1994...........................................................................................................................

29. Frequency of detection of selected major and trace elements in filtered water, lower Columbia River

Basin, Oregon and Washington, 1994................................................................................................................

30. Instantaneous loads for major and trace elements for selected low and high streamflow conditions in the

Columbia River at Warrendale, Willamette River at Portland, and Columbia River at Beaver Army

Terminal, lower Columbia River Basin, Oregon, 1994 .....................................................................................

31. Distribution of major- and trace-element concentrations in suspended sediment, lower Columbia River

Basin, Oregon and Washington, 1994................................................................................................................

32. Mass balances for streamflow, suspended zinc loads, and suspended aluminum loads, lower Columbia

River Basin, Oregon and Washington, August through September, 1994.........................................................

33. Number of historical determinations and uncensored data values for organic compounds, lower Columbia

River Basin, Oregon and Washington, 1965–93................................................................................................

34. Concentrations of organic compounds detected in filtered water, lower Columbia River Basin, Oregon

and Washington, 1994........................................................................................................................................

35. Chemical classifications for organic compounds analyzed, lower Columbia River Basin, Oregon and

Washington, 1994...............................................................................................................................................

36. Distribution of organic-compound concentrations in filtered water, lower Columbia River Basin, Oregon

and Washington, 1994........................................................................................................................................

37. Indicator-bacteria standards and concentrations of concern for Oregon and Washington streams, lower

Columbia River Basin, 1994 ..............................................................................................................................

38. Distribution of fecal-indicator bacteria concentrations, lower Columbia River Basin, 1994 ............................

39. Quality-assurance data for field measurements, lower Columbia River Basin, Oregon, 1994..........................

40. Quality-assurance data for major ions, lower Columbia River Basin, Oregon, 1994........................................

41. Quality-assurance data for nutrients, lower Columbia River Basin, Oregon, 1994...........................................
ix

42. Quality-assurance data for fecal-indicator bacteria, chlorophyll a, suspended sediment, suspended solids,

and organic carbon, lower Columbia River Basin, Oregon, 1994 .....................................................................

43. Quality-assurance data for filtered-water trace elements, lower Columbia River Basin, Oregon, 1994 ...........

44. Quality-assurance data for suspended trace element samples, lower Columbia River Basin, Oregon, 1994....

45. Quality-assurance data for organic compounds in filtered water, lower Columbia River Basin, Oregon

and Washington, 1994........................................................................................................................................

46. Point-source locations and National Pollutant Discharge Elimination System permit levels of effluent

discharge, lower Columbia River Basin, Oregon and Washington, 1994..........................................................

47. Summary of trace-element concentrations that exceed screening values derived from water-quality

guidelines, lower Columbia River Basin, Oregon and Washington, 1994 ........................................................

48. Summary of physical and microbiological measurements that exceed screening values derived from

ambient water-quality criteria, lower Columbia River Basin, Oregon and Washington, 1994 .........................

49. Summary of constituent concentrations in filtered water that did not exceed screening values derived

from water-quality guidelines, lower Columbia River Basin, Oregon and Washington, 1994 .........................

50. Summary of trends in selected water-quality constituent, lower Columbia River Basin, Oregon, 1973–95 ....

CONVERSION FACTORS

[SI = International System of units, a modernized metric system of measurement]

Factors for converting SI metric units to inch/pound units

Multiply By To obtain

Length

micrometer (μm) 0.00003937 inch (in)

millimeter (mm) 0.03937 inch

meter (m) 3.281 foot (ft)

Volume

milliliter (mL) 0.001057 quart (qt)

liter (L) 1.057 quart

liter 0.2642 gallon (gal)

Mass

nanogram (ng) 0.00000000003527 ounce (oz avoirdupois)

microgram (mg) 0.00000003527 ounce

milligram (mg) 0.00003527 ounce

gram (g) 0.03527 ounce

kilogram (kg) 35.27 ounce

Density

grams per cubic centimeter (g/cm3) 0.5780 ounces per cubic inch (oz/in3)

Temperature

degrees Celsius (°C) ( 1 )

1 Temperature °F = 1.8 (Temperature °C) + 32

degrees Fahrenheit (°F)

Concentration, in water

nanograms per liter (ng/L) 1 parts per trillion (ppt)

micrograms per liter (μg/L) 1 parts per billion (ppb)

milligrams per liter (mg/L) 1 parts per million (ppm)

Concentration, in sediment

micrograms per gram (μg/g) 1 parts per million (ppm)
x
1

Water Quality of the Lower Columbia River Basin:

Analysis of Current and Historical Water-Quality Data

through 1994

By Gregory J. Fuhrer, Dwight Q. Tanner, Jennifer L. Morace, Stuart W. McKenzie, and

Kenneth A. Skach

Abstract

The lower Columbia River Basin includes

the river basins draining into the Columbia

River below Bonneville Dam—the largest of

which is the Willamette River. This report

presents the results of a study by the U.S.

Geological Survey, done in cooperation with

the Lower Columbia River Bi-State WaterQuality Program, to describe the water-quality

conditions in the lower Columbia River Basin

by interpreting historical data collected and

data collected in 1994. Historical waterquality data spanning more than 50 years and

comprising more than 200 parameters were

collated for interpretation in this report. The

U.S. Geological Survey, the Oregon

Department of Environmental Quality, and the

Washington Department of Ecology collected

water-quality data at 10 sites in the lower

Columbia River Basin from January to

December of 1994. Water-quality constituents

measured in 1994 were screened against U.S.

Environmental Protection Agency (EPA) and

State guidelines.

Arsenic, a human carcinogen, was

detected in 15 of 16 samples in the lower

Columbia River, but was not detected in any

of the sampled tributaries. All 15 arsenic

detections had concentrations that exceeded

both the EPA ambient water-quality criteria

for the protection of human health and the

EPA human-health advisories for drinking

water. Chromium was detected at all four

Columbia River sites—most frequently in the

Columbia River at Hayden Island. None 

chromium concentrations detected, howe

exceeded water-quality criteria or guidel

Measurements of suspended traceelement concentrations (trace-element

concentrations associated with the suspe

sediment fraction) showed that the suspe

form is the dominant transport phase for

aluminum, iron, and manganese, wherea

dissolved form is the dominant transport 

for arsenic, barium, chromium, and coppe

the basis of tributary loads during summ

low-flow months, sources of suspended s

nickel, aluminum, and antimony exist in 

lower Columbia River Basin, whereas th

sources of suspended zinc and arsenic ex

outside of the lower basin.

Twenty organic compounds were det

of the 47 compounds analyzed for this st

None of the organic compounds measure

exceeded EPA’s ambient water-quality cr

or drinking-water guidelines. The Willam

River at Portland had the largest number 

detections, and all 20 compounds were

detected at one time or another at that site

largest concentrations of the agricultural

pesticides, atrazine, metolachlor, and sim

were detected in the Willamette River, w

they were detected in 93, 86, 93 percent,

respectively, of the samples collected. Th

highest concentrations of atrazine in the

Willamette River were associated with th

spring application and fall runoff period
2

Both historical and current data showed

that the highest water temperatures in the lower

Columbia River Basin are present during

August. For water years 1977–81 in the

Columbia River at Bradwood (river mile 38.9),

75 percent of the daily mean water

temperatures during August exceeded 20

degrees Celsius, a “special condition” criterion

for the State of Washington. The special

condition criterion was exceeded at four sites

on the lower Columbia River during July and

August, 1994—a period coinciding with

season-high air temperatures and low

streamflow. Trend tests using data from 1974 to

1994 showed significant (ρ < 0.05) upward

trends for water temperature at the Columbia

River at Warrendale and the Willamette River at

Portland.

Concentrations of dissolved oxygen and

total dissolved gas were above saturation levels

during high stormflows in the lower Columbia

River and the Willamette River during 1994.

The high concentrations of total dissolved gas

in the Columbia River exceeded Oregon and

Washington State standards of 110 percent of

saturation and were caused by spilling water at

the Columbia River dams. Aquatic life in the

lower Columbia River Basin was not subjected

to low dissolved-oxygen concentrations.

Comparison of dissolved-oxygen

concentrations in the Willamette River from

1949–58 to 1972–94 showed a significant

increase in dissolved-oxygen concentrations

during the low-streamflow months of summer.

 Trend tests showed significant (ρ < 0.05)

downward trends from 1973 to 1994 for three

constituents at the Columbia River at

Warrendale: phosphorus in unfiltered water,

total dissolved solids, and specific conductance.

These trends may be a consequence of more

conservative agricultural practices in the area

upstream from Warrendale.

INTRODUCTION

The Columbia River Basin (fig. 1), molded and

sculpted through geologic time, has become a

dominant landscape feature in the Pacific No

It has witnessed the birth of new mountains, 

weathering of old ones, the violent eruption

volcanoes, and some of the most cataclysmi

in Earth’s history. The basin has been home 

Native American peoples for thousands of y

has attracted explorers and settlers from man

countries. The Columbia River drains parts o

States of Washington, Idaho, Montana, Wyo

Nevada, Utah, and Oregon, and the Province 

British Columbia, where its headwaters arise

flows more than 1,200 miles from Columbia 

its mouth at the Pacific Ocean. The Columbi

has been both habitat and passageway for sa

and other aquatic life, and has had spiritual 

physical significance to Native Americans fo

centuries. As people industrialized the Pacif

Northwest, water use within the basin chang

dramatically: hydroelectric projects were co

to provide electricity, navigation channels w

constructed to promote commerce, diversion 

were constructed to increase agricultural pro

through irrigation, reservoirs were construct

reduce flooding and to provide recreational

opportunities, and cities grew along the bank

basin’s rivers.

Development within the Columbia Rive

has not been without side effects. When Cap

Robert Gray discovered the Columbia River 

an estimated 10 to 16 million adult salmon w

returning annually to the river; this salmon r

was once considered to be unlimited. Betwe

and 1990, however, only 1.1 to 2.8 million a

returned each year. Not only has the total nu

salmon declined drastically, but the average 

returning adults is markedly smaller for seve

stocks. An estimated 67 individual stocks ha

permanently eliminated, 4 stocks are present

as threatened or endangered under the Endan

Species Act, and an additional 72 stocks are 

to be in jeopardy.

Concern about degradation of water qu

the Columbia River Basin began in the late 

(P. Klingeman, Oregon State University, wri

commun., 1995). Hydropower development,

irrigated agriculture, logging, mining, stream

channelization, and urbanization are recogni

contributing factors. Hydroelectric and agric

development have changed the quantity and 

of seasonal runoff, modifying water tempera
3

Figure 1. The Columbia River Basin.
4

and sometimes supersaturating the river water with

air, which can cause gas-bubble trauma in fish.

Dissolved-oxygen levels, while adequate in the

Columbia River, have been depressed in some

tributaries by municipal and industrial wastes. The

Snake and Willamette Rivers are known to be the

major contributors of nitrogen and phosphorus to

the Columbia River. Suspended sediment tends to

increase in subbasins influenced by logging and

agriculture. Toxic chemicals, such as pesticides,

polychlorinated biphenyls (PCB), and trace

elements, have been found in fish of the Columbia

River Basin, resulting in at least one recent human

health advisory (Stober and Nakatani, 1992).

Radioactivity in the lower Columbia River has

historically been of concern, a result of Hanford’s

eight plutonium production reactors which, one by

one, have been closed (Toombs and others, 1983).

Additionally, radionuclides have historically been

of concern. Unquestionably, today’s water managers

face a difficult and complex task as they strive to

maintain a healthy environment in the basin, while

maintaining the livelihood of the people who live

in it.

Background

The Lower Columbia River Bi-State WaterQuality Program was initiated in 1990 by the

Governors of Oregon and Washington. On the basis

of workshops and public comments, the Governors

concluded that the study of the lower Columbia

River Basin would receive broader support in a BiState study framework than as part of the Federal

Government’s National Estuary Program. The BiState study is a 4-year program that is sponsored

jointly by the Washington Department of Ecology

(WDOE), the Oregon Department of Environmental

Quality (ODEQ), the Washington and Oregon

Public Port Associations, and the Northwest Pulp

and Paper Association. A Bi-State steering

committee was created to assist WDOE and ODEQ

in administering this program, which will study

water quality below Bonneville Dam (river mile

[RM] 146.1). The committee is composed of

representatives from local governments, industries,

Native American Tribes, fishing groups,

environmental groups, the general public, public

ports, and Federal agencies. On the basis of the

water-quality information obtained, the steering

committee will evaluate options and provide

recommendations for improving and protect

water quality and beneficial uses in the Colu

River. ODEQ and WDOE will also be review

and making their own determinations, in add

responding to recommendations made by the

steering committee.

The Bi-State steering committee identi

several major goals for the water-quality pro

the lower Columbia River. The goals are as 

1. Provide a regionally consistent descriptio

water-quality conditions;

2. Define seasonal and long-term trends (or 

trends) in water quality; and

3. Identify, describe, and explain, as possibl

major factors that affect observed water-q

conditions and trends.

Within the framework of the Bi-State s

numerous preliminary tasks have been comp

assess water quality in the lower Columbia R

(Tetra Tech, Inc., 1993). Preliminary tasks in

establishing a library database for isolating 

gaps and identifying problem areas. Because 

quality data were sparse, however, the entire 

Columbia River was considered a data gap i

Also important was an inventory of pollutan

sources, which included point sources, nonp

sources (dispersed water-based activities or

dispersed land-based activities), and in-plac

sources (landfill leachate). On the basis of a

data, pollutant-loading estimates were made 

point sources and were used to identify appr

analytical suites as well as to aid in the selec

sampling sites for a reconnaissance study. A

literature review of physical and hydrologic

characteristics of the lower Columbia River 

conducted to assist in determining the poten

environmental fate of pollutants. Biological

indicator species were selected on the basis 

existing data for major habitats and biologic

communities, and from biological exposure

(bioaccumulation) and response (community

structure) studies. To determine areas that ar

especially sensitive to pollutants, river miles 

lower Columbia River were characterized ac

to the various beneficial uses of rivers, such 

supply, recreation, or fish and wildlife.

The lower Columbia River reconnaissa

sampling was conducted from September thr

November 1991 (Tetra Tech, Inc., 1993). Wa
5

samples were collected from 45 sites in the lower

Columbia River and analyzed for trace elements,

nutrients, and other parameters. Nutrient

concentrations were not quantified because

analytical-method reporting limits for nutrients

were higher than the nutrient concentrations in the

samples. Aluminum, barium, iron, and lead were the

only trace elements that were frequently detected.

Analytical-method reporting limits for several trace

elements, including lead, mercury, nickel, selenium,

and silver, were greater than the U.S. Environmental

Protection Agency’s (EPA) ambient water-quality

criteria, thus hampering identification of trace

elements of concern (U.S. Environmental Protection

Agency, 1986a). Organic constituents were

measured at five sites; in general, semivolatile and

volatile organic compounds, pesticides, and PCBs

were not detected, with the exception of bis(2-

ethylhexyl)phthalate, a common laboratory

contaminant. The investigators noted that some of

the target organic compounds may have been

present at concentrations that were undetectable

using the conventional methods employed for the

reconnaissance study. Bulk sediment samples were

collected at 54 sites in the lower Columbia River

and analyzed for trace elements, organic

compounds, dioxins and furans, and other

miscellaneous parameters. Fish-tissue samples were

collected at 18 sites and analyzed for trace elements

and organic compounds. Benthic community

structure was assessed at 54 sites. All organisms

removed from the streambed sediment were

enumerated and identified to the lowest practical

taxonomic level, generally genus or species.

Supplemental reconnaissance measurements in

backwater areas of the Columbia River were made

in 1993 (Tetra Tech, Inc., 1994). Backwater areas

are hydrologically low-energy areas that promote

the settling of fine-grained sediment and associated

contaminants. Water samples from 15 backwater

sites were analyzed for trace elements, nutrients,

bacteria, and other parameters. Water temperatures

at several backwater sites exceeded Washington

State’s temperature standard of 20oC (degrees

Celsius). In backwater environments,

concentrations of nitrogen and phosphorus

approached concentrations that, under proper

conditions of light and temperature, have caused

nuisance algal blooms in lake environments.

Investigators noted that concentrations of

aluminum, iron, copper, and lead from unfiltered

samples frequently exceeded EPA’s ambient 

quality criteria for chronic toxicity to aquati

Investigators also concluded that exceedance

principally by trace elements associated with 

suspended-sediment fraction. Streambed sed

from the 15 backwater sites also were sampl

concurrently for trace elements and organic

compounds. On the basis of normalization

techniques, some trace elements, such as ars

backwater areas and copper in the main stem

have anthropogenic sources. Pesticides were

detected infrequently; the infrequent detecti

attributed to the diffuse nature of pesticide i

from agricultural sources and the lack of loc

nearshore sources. Polyaromatic hydrocarbo

however, were detected in the vicinity of urb

industrial sources.

Purpose and Scope

Historically, water-quality studies in th

Columbia River have focused on specific riv

reaches; many of these studies lack the cont

necessary to assess water quality in a river-b

framework. The Bi-State study has addresse

data gap by initiating an ambient-monitoring

program that will assess temporal variations 

constituent concentrations and loads in 1994

The purpose of this report is to describ

water-quality conditions in the lower Colum

River and major tributaries to the extent pos

by:

(1) Examining seasonal variations in concen

of water-quality constituents in water (fi

and unfiltered) and suspended sediment;

(2) Portraying spatial variations in historical 

quality data;

(3) Determining trends in concentrations of 

quality constituents in water (filtered an

tered) and in physical water-quality mea

ments (for example, water temperature) 

with adequate historical data;

(4) Analyzing the suitability of surface wate

maintenance of aquatic life and protectio

human health;

(5) Determining instream loads for selected 

quality constituents and comparing instr

loads in major subbasins to instream load

Columbia River; and
6

(6) Listing point sources and, to the extent possible,

the associated discharges.

Acknowledgments

The authors wish to acknowledge the aid and

advice provided by the members of the Bi-State

Steering Committee. The committee included:

Ralph Ennis Salmon For All

Nelson Graham Longview City Manager

Mike Lindberg Portland City Commissioner

Al Whitford Longview Fibre Company

Llewellyn Matthews Northwest Pulp and Paper

Association

Rollie Montagne Port of Portland

Glenn Vanselow Pacific Northwest Waterways

Association

Steve Wille Southwest Washington

Anglers

Elmer Scott, Jr. Warm Springs Reservation

Wilbur Slockish, Jr. Native American Tribes

Cyndy deBruler Columbia River United

Jean R. Cameron Oregon Environmental

Council

Carol Schuler U.S. Fish and Wildlife

Service

Jeremy Buck U.S. Fish and Wildlife

Service

Jim Bergeron Citizen-at-large

Carol Carver Citizen-at-large

Stuart McKenzie U.S. Geological Survey

R. Ted Bottiger Northwest Power Planning

Council

Joyce Cohen Northwest Power Planning

Council

Andy Schaedel Oregon Department of

Environmental Quality

(Staff)

Don Yon Oregon Department of

Environmental Quality

(Staff)

Bill Young Oregon Department of

Environmental Quality

(Staff)

David Peeler Washington Department of

Ecology (Staff)

Brian Offord Washington Department of

Ecology (Staff)

Helen Bresler Washington Department of

Ecology (Staff)

 John Gabrielson U.S. Environmental

Protection Agency

Special thanks to: (1) Willamette Basin

National Water-Quality Assessment (NAWQ

Program and Willamette State Study (both U

projects) for sharing some of the sampling a

laboratory efforts; (2) Doug Cushman (USG

data collection; (3) Matt Johnston (USGS) f

performing solid-phase extractions, organic-

filtrations, and centrifugation; (4) Don Ande

(USGS) for centrifuging efforts; (5) Larry

Scharnberg (USGS) for performing the chlo

determinations; (6) Carol Lewis (USGS, Res

Virginia) for performing the data retrieval fr

EPA’s database; (7) Doug Terra (ODEQ) for

providing Tetra Tech, Inc. data from the 199

(8) Bill Ehinger (WDOE) and Greg Pettit (O

for collecting water-quality data in 1994; (9

Nesbit (ODEQ), Holly Francis, Cindy James

Tim Hilliard (all of WDOE) for their assista

obtaining and clarifying point-source data; a

Karl Lee (USGS) for streamflow calculation

THE LOWER COLUMBIA RIVER BA

The Columbia River drains an area of 2

square miles and is ranked seventh in length 

fourth in streamflow among United States ri

(U.S. Geological Survey, 1981; Saboe, 1991

flows 1,243 miles from its headwaters in the

Canadian Rockies of British Columbia, acro

State of Washington, and along the border o

Washington and Oregon to its mouth at the P

Ocean (fig. 1). There are 11 dams on the Co

River’s main stem in the United States and 1

that form reservoirs with capacities greater t

5,000 acre-feet in the United States and Can

parts of the basin. The northern and eastern 

of the Columbia River Basin contain mainly

sedimentary and metamorphic rocks, wherea

southern, western, and central parts contain 

igneous rocks.

The lower Columbia River Basin, the su

this report, drains the area from Bonneville 

the mouth of the Columbia River (fig. 2). In 

lower basin, the Columbia River flows 146.1 

and drains an area of about 18,000 square m

to the west of the crest of the Cascade Rang

major tributaries and associated drainage are

lower Columbia River Basin, in downstream 

are the Sandy River (500 square miles), the
7

Kalama River

Cowlitz

River

RIVER

River

Sandy

Lewis

River

River

Willamette

COLUMBIA

R A N G E

R A N G E

C O A S T

C A S C A D E

Vancouver

Kalama

Longview

Bonneville

Dam

Eugene

Government

 Camp

Salem

Portland

Rainier

Prescott

Goble

Altoona

Wauna

Warrendale

Bradwood

Astoria

Cougar

10 20 30 MILES

0 10 20 30 KILOMETERS

0

124 123 122 47

46

45

44

Base from U.S. Geological Survey, 1:100,000, 1986

Universal Transverse Mercator, zone 10

Figure 2.Central meridian 123W, standard parallels 126W−120W The lower Columbia River Basin, Oregon and Washington.
8

Willamette River (11,400 square miles), the Lewis

River (1,000 square miles), the Kalama River (200

square miles), and the Cowlitz River (2,500 square

miles).

Precipitation

Precipitation varies considerably across the

lower Columbia River Basin but generally exceeds

that in the rest of the Columbia River Basin. The

Cascade Range creates a rain shadow which is

responsible for the greater quantities of

precipitation in the lower Columbia River Basin.

Historically, mean annual precipitation in the lower

Columbia River Basin ranged from 113 inches at

Cougar, Washington, to about 37 inches at Portland,

Oregon (fig. 3) and was generally higher in the

mountains (Cougar and Government Camp) and on

the coast (Astoria) than in the valleys (Portland and

Eugene). Intrasite variations in annual precipitation

can be large depending on meteorological

conditions. For example, annual precipitation at

Cougar ranged from as little as 78.27 inches in 1952

to as much as 141.84 inches in 1983 (Earth-Info,

Inc., 1993). The annual precipitation at Portland for

the 1994 water year (WY) was 36.32 inches

(Oregon Climate Service, 1994), which is similar to

the mean annual precipitation.

Most of the precipitation in the lower

Columbia River Basin falls from November through

March. The mean monthly precipitation during this

period, in Portland, Eugene, and Cougar was 66, 70,

and 71 percent, respectively, of the mean annual

precipitation (fig. 4).

Streamflow Conditions

The Willamette River is the major tributary of

the lower Columbia River. It drains 65 percent of

the area within the lower Columbia River Basin. On

the basis of mean annual streamflow for the period

1928–65 (Orem, 1968), the Willamette River’s

discharge represented 17 percent of the streamflow

in the Columbia River at Vancouver, Washington,

which is located 0.5 miles upstream from the

confluence of the Willamette and Columbia Rivers.

For those same years, the Willamette River’s

contribution to the Columbia River’s total

streamflow at its mouth near Astoria, Oregon,

averaged 13 percent. Compared with other lower

Basin tributaries during the period 1928–65, 

Willamette River streamflow represented 58 

of the increase in Columbia River streamflow 

Vancouver and the mouth.

Streamflow in the main stem of the low

Columbia River is affected by spring snowm

winter rainstorms, and regulation by many d

addition to the dams on the main stem of the

Columbia River and the many other dams on

tributaries above Bonneville Dam, there are 

reservoirs in the Willamette River Basin, 3 r

in the Lewis River Basin, and 2 reservoirs in 

Cowlitz River Basin. Daily flood-control reg

generally required during the spring snowme

Outflows and forebay levels at Grand Coulee 

specified by the U.S. Army Corps of Engine

between May and June in order to provide st

capacity to dampen peak flows. During the 1

for example, the regulated peak flow at The 

during the snowmelt season was 382,000 ft3

feet per second), while the unregulated peak 

would have been 602,000 ft3/s. Local floodi

lower Columbia River begins when streamfl

reaches about 450,000 ft3/s (Columbia River 

Management Group, 1994).

In the Willamette River Basin, reservoi

operated by the U.S. Army Corps of Engine

reach minimum flood-control elevations betw

November 1 and 15 in reservoirs not generat

and by November 30 in reservoirs generatin

Much of the runoff during February and Ma

to rainfall. At the higher elevations, howeve

precipitation occurs as snow, and runoff is o

delayed until the spring snowmelt. During fl

water is held in reservoirs until downstream

discharges from unregulated streams have su

and then released at a rate that does not exce

established flood-regulation goals. The well

limits of the flood season allow winter storm 

and spring snowmelt runoff to be impounded 

subsequently released during low water cond

summer and early fall (U.S. Army Corps of E

1989). Releases during summer and fall are 

satisfy requirements for fisheries, irrigation,

navigation, and pollution abatement.
9

0

150

25

50

75

100

125

BONNEVILLE DAM GOVERNMENT CAMP, OREGON

1920 21920 1930 1940 1950 1960 1970 1980 1990

YEAR

ASTORIA, OREGON

1920 2000 1920 1930 1940 1950 1960 1970 1980 1990

YEAR

0

150

25

50

75

100

125

COUGAR, WASHINGTON

0

150

25

50

75

100

125

ANNUAL PRECIPITATION, IN INCHES

PORTLAND, OREGON EUGENE, OREGON

Mean

Mean

Figure 3. Annual and mean annual precipitation at Bonneville Dam, Government Camp, Portland, Eugene, Cougar, and 

lower Columbia River Basin, Oregon and Washington, 1920–93.
10

0

20

2

4

6

8

10

12

14

16

18

MEAN MONTHLY PRECIPITATION, IN INCHES

PORTLAND, OREGON 1941- 93

COUGAR, WASHINGTON 1948-93

0

20

2

4

6

8

10

12

14

16

18

EUGENE, OREGON 1905- 93

OCT NOV DEC JAN FEB MAR APR MAY JUNE JULY AUG SEPT

WATER YEAR

0

20

2

4

6

8

10

12

14

16

18

Figure 4. Mean monthly precipitation at Portland, Cougar,

and Eugene, lower Columbia River Basin, Oregon and

Washington.

In the Columbia River, streamflow is ty

high in spring during the snowmelt season. A

winter streamflows are high because of wint

they are generally not as high as during snow

Streamflows peaked as a result of spring sno

during the months of April, May, and June f

1956 WY and during June for the 1967 WY 

There was, however, no spring peak in the 19

The 1956, 1967, and 1977 WY’s represent,

respectively, the high-flow (351,000 ft3/s), m

flow (259,000 ft3/s), and low-flow (153,000 

water years for the period 1928–84 (fig. 6)—

on mean daily streamflow in the Columbia R

mouth (Orem, 1968; U.S. Geological Survey

75, 1976–80, 1981–84). Peak daily mean

streamflows during snowmelt seasons have r

from 917,000 ft3/s during June of 1948 to on

179,800 ft3/s during May of 1977.

The spring snowmelt season usually co

with the major streamflows of the year. Durin

a year of median streamflow, more than 40 p

of the annual streamflow in the Columbia Ri

Vancouver was discharged from April throug

during the spring snowmelt period (table 1). 

the 1994 WY, however, spring snowmelt run

notably less than during the 1967 median stre

year (fig. 7). The annual mean streamflow (1

ft3/s) measured in the Columbia River at Be

Army Terminal near Quincy for the 1994 W

among the lowest 10 percent for the period 1

The Willamette River’s seasonal stream

pattern is different from that of the Columbi

In 1967, the Willamette River discharged on

percent of its annual streamflow during sprin

64 percent during the December through Ma

winter months (table 1). In contrast, 41 perc

the streamflow in the Columbia River at Van

was discharged during spring and only 24 pe

during winter. The 1994 hydrographs for the

Columbia and Willamette Rivers (fig. 8) illu

the same seasonal streamflow patterns—pea

on the Columbia River were during May and 

and on the Willamette River, rainstorm-drive

were measured from January through April a

again from November through December.
11

O N D J F M A M J J A S

WATER YEAR

0

800

200

400

600

MONTHLY MEAN STREAMFLOW,

IN THOUSANDS OF CUBIC FEET PER SECOND

EXPLANATION

HIGH-STREAMFLOW YEAR, 1956 WATER YEAR

MEDIAN-STREAMFLOW YEAR, 1967 WATER YEAR

LOW-STREAMFLOW YEAR, 1977 WATER YEAR

Figure 5. Estimated monthly mean streamflow in the

Columbia River at mouth near Astoria for the low-, median-,

and high-streamflow years, lower Columbia River Basin,

Oregon.

Figure 6. Annual mean streamflow and median annual streamflow for the Columbia River at mouth, 1928–84.

(Data from Orem, 1968; U.S. Geological Survey, 1972-75, 1975-80, 1981-84.)

YEAR

1930 1940 1950 1960 1970 1980 19

0

500

100

200

300

400

ANNUAL MEAN STREAMFLOW, IN THOUSANDS OF CUBIC FEET PER SECOND

1956, HIGH FLOW YEAR

1967, MEDIAN FLOW YEAR

1977, LOW FLOW YEAR

Median

O N D J F M A M J J A 

WATER YEAR

0

800

100

200

300

400

500

600

700

MONTHLY MEAN STREAMFLOW,

IN THOUSANDS OF CUBIC FEET PER SECOND

EXPLANATION

COLUMBIA RIVER AT BEAVER ARMY TERMINA

1994 WATER YEAR

COLUMBIA RIVER AT MOUTH, 1967 WATER Y

Figure 7. Estimated monthly mean streamflow in the 

River at mouth near Astoria, 1967 water year, and C

River at Beaver Army Terminal near Quincy, 1994 w

lower Columbia River Basin, Oregon and Washingt
12

Land and Water Use

Major land-use categories1 in the lower

Columbia River Basin include forest land (74

percent) and agricultural land (17 percent) (table 2).

Urban lands comprise a relatively small part (5

percent) of the basin, but are significant to water use

and water quality. Intensive water use by cities and

some agricultural areas makes these land uses of

primary importance to water-quality issues. Most of

the agricultural land in the lower Columbia River

Basin is in the Willamette River Basin (fig. 9).

Although the Willamette River Basin makes up 65

percent of the area in the lower Columbia River

Basin, it contains 89 percent of the lower basin’s

agricultural land.

Population in the lower Columbia River Basin

was about 2,344,800 in 1990 (T.M. Broad and C.A.

Collins, USGS, unpub. data, 1993), with more than

80 percent residing in the Willamette River Basin.

As a result, the Willamette River Basin ranks high

in terms of water use in the lower Columbia River

Basin (table 3), accounting for more than 60 percent

of the surface-water and ground-water withdrawals

in the lower Columbia River Basin. Commercial2,

industrial3, livestock, and irrigation withdrawals in

the Willamette River Basin are large in comparison

1

Land-use data are from the EPA’s 1980 land-use and landcover digital data (U.S. Environmental Protection Agency, 1994a),

which uses the Anderson classification system of land use and land

cover (Anderson and others, 1976).

2

Water used for motels, hotels, restaurants, office buildings,

and other commercial facilities, and institutions, both civilian and

military.

Table 1. Summary statistics for seasonal variations in streamflow at selected sites, lower Columbia River Basin

and Washington, 1967 water year

[Streamflow reported in thousands of cubic feet per second; Vancouver, Columbia River at Vancouver; Willamette, Willamette River at P

Helens, Columbia River at St. Helens; Longview, Columbia River at Longview; Astoria, Columbia River at mouth near Astoria; data are f

water year, a median-streamflow year for the period 1928–85; Fall, October to November; Winter, December to March; Spring, April to Ju

July to September]

Site name

Percent of the annual streamflow Mean monthly streamflow

Fall Winter Spring Summer Fall Winter Spring Summ

Vancouver 9 24 41 26 105 146 332 213

Willamette 14 64 16 6 27.0 65.0 19.6 7.5

St. Helens 10 30 37 23 138 219 356 221

Longview 10 32 36 22 144 239 368 224

Astoria 10 32 35 23 150 254 367 233

to other subbasins in the lower Columbia Ri

Basin. In the Willamette River Basin, for ex

industrial and irrigation withdrawals, respec

represent 55 and nearly 87 percent of the tot

industrial and irrigation withdrawals in the l

Columbia River Basin.

Point Sources

In this report, point sources are defined 

or outfall discharges from municipalities and

industries. These sources may flow directly 

main stem of the Columbia River or into one 

tributaries. Nonpoint sources include diffuse 

such as overland runoff and ground-water di

Both point and nonpoint sources may degrad

quality; however, point sources are usually m

easily identified and controlled. In addition, 

sources include combined-sewer overflows (

which usually occur in the winter in the Wil

River and the Columbia Slough, which drain

lower Willamette River. Between RM 0 and 2

Willamette River, there are a total of 38 CSO

another 13 in the first 10 river miles of the C

Slough (Warner and others, 1992).

One hundred and two point sources we

identified as directly connected to the main 

located within the first 16 river miles of trib

(table 46, at back of report). These sources a

3Water used in processing, washing, cooling in facili

manufacture products such as steel, chemical and allied pr

paper and allied products, and petroleum refining.
13

Figure 8. Streamflows in the Willamette River at Portland and Columbia River at Warrendale, lower Columbia River 

Oregon and Washington, 1994. (Data for the Columbia River at Warrendale are outflow from Bonneville Dam from th

U.S. Army Corps of Engineers.)

J F M A M J J A S O N D

1994

0

250

50

100

150

200

DAILY-MEAN STREAMFLOW, IN THOUSANDS OF CUBIC FEET PER SECOND

0

250

50

100

150

200

DAILY-MEAN STREAMFLOW, IN THOUSANDS OF CUBIC FEET PER SECOND

COLUMBIA RIVER AT WARRENDALE

WILLAMETTE RIVER AT PORTLAND
14

facilities that have National Pollutant Discharge

Elimination System (NPDES) permits to discharge

wastewater. These facilities were classified

according to their primary function in order to

examine the pollution contributions of different

types of industries and their resulting wastewater

(table 4). The largest category of point sources is

domestic facilities, which are primarily sewagetreatment plants. The locations of these facilities are

shown in figure 10. All other point sources are

shown in figure 11.

ODEQ and WDOE issue and enforce the

NPDES permits in Oregon and Washington. These

permits specify the discharge limits that must not be

exceeded during the operation of the facility and the

frequency and type of monitoring that must be

performed. The information in table 46 (at back of

report) was obtained from the permit files of ODEQ

and from the permits database of WDOE.

Information on point sources that discharge directly

into the Columbia River came from a report done by

Tetra Tech, Inc. for the Lower Columbia River BiState Program (Tetra Tech, Inc., 1992). The permit

levels for effluent discharge shown in table 46 (at

back of report) represent average or maximum

permitted effluent quantities and do not necessarily

represent actual discharges. Caution should be taken

in comparing values in the table because the time

frame that the levels are based on differs with each

facility. For some facilities, limits have not been set

on flow, and levels are based on the “average dryweather design flow” to the facility. Facilities that

are classified as “industrial” by ODEQ or WDOE

have limits on the concentrations of selected

Table 2. Percentage of land in specific land-use and land-cover categories, lower Columbia River Basin, Oregon and

Washington, 1980

[Land-use percentages from U.S. Environmental Protection Agency, 1994a; %, percent]

Area name Urban

land

Agricultural

land

Forest

land

Water bodies

and wetlands

Other

land

Total land area

(square miles)

Lower Columbia River Basin 5 % 17 % 74 % 3 % 1 % 17,670

Willamette River Basin

(Hydrologic Units

17090001–17090012)

5 % 23.5 % 69.5 % 1 % 1 % 11,426

Non-Willamette areas of the

lower Columbia River Basin

(Hydrologic Units

17080001–17080006)

4 % 5 % 83 % 5 % 3 % 6,244

constituents in their discharge and not on th

discharge rate. Likewise, facilities that disch

stormwater do not have flow limits.

Figure 10 shows only those facilities cl

as domestic. The largest sources of effluent 

are the Portland (Columbia Boulevard) and

Vancouver (East and West) sewage-treatmen

which serve the largest populations within 1

miles of the lower Columbia River. Figure 1

facilities that fall in the next three largest cat

chemical plants, seafood processing plants, 

other miscellaneous facilities, respectively. T

largest sources of effluent volume for these

categories are Elf Atochem North America, 

inorganic chemical manufacturer in Portland

Chevron Chemical Company, a fertilizer pla

Helens.

DATA SOURCES AND

METHODS OF ANALYSIS

The purposes of this study include exam

the spatial and temporal variations in water-

constituent concentrations, loads, and trends 

lower Columbia River Basin and describing 

suitability of surface water for the preservat

aquatic life and the protection of human hea

order to meet these goals, it was necessary n

to collect water-quality data, but also to com

analyze data that had been previously collec

current and past data were then related in a c

framework in an effort to understand the wa

quality of the River.
15

Table 3. Water use in the lower Columbia River Basin, Oregon and Washington, 1990 water year[Mgal/d, million gallons per day; --, no data; water-use data from Broad and Collins, USGS, unpub. data, 1993]

Hydrologic unit or

subbasin name

Population (in thousands)

Total withdrawals

(Mgal/d)

Selected withdrawals

(Mgal/d)

Public supply water

Commercial withdrawls and deliveries

Industrial withdrawls and deliveries

Livestock

Irrigation

Lower Columbia-Sandy, Oregon 31 170 120 45 0.4 0.1 1.2 Lower Columbia-Sandy, Washington 210 136.5 29.7 4.1 90.4 .91 13.7 Willamette River Subbasin. Oregon(including Lower Willamette Unit)

1,927.6 1,100 170 235 220 3.7 358.4 

Lewis, Washington 36.2 19 .98 .14 .01 0 14.7 Lower Columbia-Clatskanie, Oregon 21.4 92 2.1 13 60 -- 1.3 Lower Columbia-Clatskanie, Washington 49.9 26.7 6.2 .55 13.5 .16 5.9 Cowlitz River Subbasin, Washington 44.4 164 4.5 .37 17.3 1.2 16.8 Lower Columbia (estuary), Oregon 22.7 52 7.2 45 1.2 .1 .3 Lower Columbia (estuary), Washington 1.57 .18 .13 0 0 0 0 Total 2,344.8 1,760.4 340.8 343.2 402.8 6.2 412.3 
16

Kalama River

Cowlitz

River

RIVER

River

Sandy

Lewis

River

River

Willamette

COLUMBIA

R A N G E

R A N G E

C O A S T

C A S C A D E

A4

A5

A6 A3

A2

B12

A1

A1

B10

B8 B11

B7

B9

B3

B5

B6

B4

B1

B2

10 20 30 MILES

0 10 20 30 KILOMETERS

0

124 123 122 47

46

45

44

EXPLANATION

Urban lands

Agricultural lan

Forest lands

Water and wetla

Hydrologic unit 

Basin border

Hydrologic unit 

Land Use from U S Environmental Protection Agency 1994

Figure 9. Land use and land cover by hydrologic units, lower Columbia River Basin, Oregon and Washington, 1980.
17

Current and Historical Sources of Data

Data collected in 1994 are referred to as

current data, and data collected before 1994 are

referred to as historical data. Current data were

collected by the USGS, ODEQ, and WDOE,

whereas historical data span a longer timeframe and

were collected by many agencies.

Historical Data

Water-quality data for more than 200

parameters collected from streams in the lower

Columbia River Basin over more than 50 years were

collated for interpretation in this report. These data

are from three sources: EPA’s STOrage and

RETreival (STORET) database, USGS’s National

Water Information System (NWIS) database, and

Tetra Tech, Inc. synoptic studies. The retrievals

were confined to the hydrologic units inside the

lower Columbia River Basin (table 5). The STORET

retrieval consisted of data from non-USGS agencies

including EPA, U.S. Forest Service, ODEQ, and

WDOE; the NWIS retrieval consisted only of USGS

data.

Water-quality data of particular relevance were

collected at the following three fixed sites in the

Table 4. Inventory of point-source classifications,

lower Columbia River Basin, Oregon and Washington

Source classification

Number

of

facilities

Domestic 39

Chemical 12

Wood products and wood treatment 11

Miscellaneous 10

Seafood processing 8

Paper and pulp 5

Aluminum 4

Boat yard 3

Fish hatchery 3

Remediation (site cleanup) 3

Power generating 2

Tank farm (storage) 2

lower Columbia River Basin as part of the U

NAtional Stream Quality Accounting Netwo

(NASQAN):

Columbia River at Warrendale (RM 14

1973 to October 1993) Willamette River at P

(RM 12.8—October 1974 to current year) C

River at Beaver Army Terminal (RM 53.8—

November 1990 to current year).

In 1992, the NASQAN site at Warrenda

moved to Beaver Army Terminal to obtain a 

accounting of constituents leaving the Colum

River Basin. Prior to discontinuing data coll

Warrendale, however, the NASQAN program 

the sampling of concurrent data in 1992 from

Warrendale and Beaver Army Terminal. As a 

Bi-State interest in the lower Columbia Rive

the NASQAN program funded continued ope

the Warrendale site through October 1993. T

NASQAN suite of constituents measured at 

Warrendale and Beaver Army Terminal sites 

extensive. More constituents were measured 

1993–95 at the Willamette River site, howev

because of other USGS programs sampling th

sampling was partially funded by the USGS

National Water Quality Assessment (NAWQ

program (1993–95) in the Willamette Basin 

and Thompson, 1994), and by a Willamette 

Study cooperative program (1993–95) betwe

USGS and ODEQ. NASQAN samp-ling at th

sites was done once every 2 months, but sam

the Willamette River site was done once a m

during 1993–95 because of the other program

samples were collected for priority pollutant 

elements and organic compounds.

Through the Bi-State Program, Tetra Te

performed two synoptic studies on the lower

Columbia River. A reconnaissance survey of 

stem during September to November 1991 w

implemented to make a preliminary assessm

water-quality conditions and to direct future 

studies (Tetra Tech, Inc., 1993). Four enviro

media (water, streambed sediments, fish tiss

benthic organisms) were sampled. For this r

however, interpretation of historical data wa

restricted to the 45 sites for which the water 

was sampled. Due to high method reporting 

and data flagged as “unusable,” only selecte

parameters (pH, turbidity, dissolved oxygen
18

Astoria Longview

Vancouver

Portland

10 20 30 MILES

0 10 20 30 KILOMETERS

0

124 00 123 00 122 00

46 30

46 00

45 30

45 00

EXPLANATION

Effluent discharge levels−−In millions of gallons per day

 0.0035

 15.2

 100 (Portland Sewage Treatment Plant)

Basin border

Figure 10. Point-source domestic discharges, lower Columbia River Basin, Oregon and Washington, 1994.
19

Astoria Longview

Vancouver

Portland

10 20 30 

0 10 20 30 KILOMETERS

0

124 00 123 00 122 00

46 30

46 00

45 30

45 00

EXPLANATION

Chemical plant

Seafood processing

Aluminum plant

Paper and pulp

Wood products

Basin border

Figure 11. Locations of point sources other than domestic discharge, lower Columbia River Basin, Oregon and

Washington, 1994.
20

Astoria Longview

Vancouver

Portland

10 20 30 MILES

0 10 20 30 KILOMETERS

0

124 00 123 00 122 00

46 30

46 00

45 30

45 00

EXPLANATION

Boat yard

Power generation

Fish hatchery

Tank farm

Remediation

Miscellaneous

Basin border

Figure 11. Locations of point sources other than domestic discharge, lower Columbia River Basin, Oregon and

Washington, 1994—Continued.
21

Astoria Longview

Portland

10 20 30 MILES

0 10 20 30 KILOMETERS

0

124 00 123 00 122 00

46 30

46 00

45 30

45 00

EXPLANATION

Effluent discharge levels−−In millions of gallons per day

 0.003285

 37

 No discharge data available

Basin border

Elf Atochem North America

(37 million gallons per day)

Chevron Chemical Company

(8.3 million gallons per day)

Figure 12. Point-source discharges for chemical, seafood processing, and other miscellaneous facilities, lower Colum

Basin, Oregon and Washington, 1994.
22

temperature, specific conductance, salinity, total

suspended solids, chloride, sulfate, hardness, fecalcoliform bacteria, and enterococcal bacteria) were

examined. In 1993, a second synoptic study was

performed to supplement the 1991 data (Tetra Tech,

Inc., Redmond, Washington, unpub. data, 1994).

During this survey, water, streambed-sediment, and

fish-tissue samples were collected in backwater

areas (locations isolated from the main river current

with an outlet to the main channel, for example,

sloughs and back channels) of the lower Columbia

River. The interpretation for the present report was

limited to the 15 sites for which the water column

was sampled. The parameters of interest were

mainly physical properties, nutrients, bacteria, and

trace elements.

Historical water-quality data were categorized

into eight constituent groups: (1) major ions;

(2) water temperature and pH; (3) dissolved oxygen;

(4) nutrients, including those constituents

containing nitrogen and phosphorus; (5) trac

elements; (6) organic compounds, including 

carbon, pesticides, and priority organic pollu

identified by the EPA (U.S. Environmental

Protection Agency, 1995); (7) suspended-sed

concentrations in water; and (8) bacteria, inc

fecal coliform and enterococci. The number 

historical determinations for each of these g

shown in figure 13. Data from the Willamett

Basin are also shown separately in the figure 

illustrate the fact that most of the historical d

are available for the lower Columbia River B

comes from the Willamette River Basin. Tab

provides an overview of the sites with the m

determinations, by constituent group, in the 

From this table, it can be seen that the Bull R

Watershed (Portland’s drinking-water source

been frequently sampled in the past.

Table 5. Hydrologic units included in historical data retrievals and subbasin units used for analysis of historical d

lower Columbia River Basin, Oregon and Washington

[Historical data was retrieved for all hydrologic units except 17080004; hydrologic unit descriptions from U.S. Geological Survey, 1982]

Hydrologic

unit Hydrologic unit name Subbasin or unit name used foranalysis of historical data

17080001 Lower Columbia-Sandy, Oregon, Washington Lower Columbia-Sandy, Oregon

17080001 Lower Columbia-Sandy, Oregon, Washington Lower Columbia-Sandy, Washington

17080002 Lewis, Washington Lewis River Subbasin

17080003 Lower Columbia-Clatskanie, Oregon, Washington Lower Columbia-Clatskanie

17080004 Upper Cowlitz, Washington Cowlitz River Subbasin

17080005 Lower Cowlitz, Washington Cowlitz River Subbasin

17080006 Lower Columbia, Oregon, Washington Lower Columbia (estuary) Unit

17090001 Middle Fork Willamette, Oregon Willamette River Subbasin

17090002 Coast Fork Willamette, Oregon Willamette River Subbasin

17090003 Upper Willamette, Oregon Willamette River Subbasin

17090004 McKenzie, Oregon Willamette River Subbasin

17090005 North Santiam, Oregon Willamette River Subbasin

17090006 South Santiam, Oregon Willamette River Subbasin

17090007 Middle Willamette, Oregon Willamette River Subbasin

17090008 Yamhill, Oregon Willamette River Subbasin

17090009 Molalla-Pudding, Oregon Willamette River Subbasin

17090010 Tualatin, Oregon Willamette River Subbasin

17090011 Clackamas, Oregon Willamette River Subbasin

17090012 Lower Willamette, Oregon Lower Willamette Unit
23

Table 6. Sites that have the most water-quality determinations from 1939–93, lower Columbia River Ba

and Washington

[Listed are the five sites with the most water-quality data values for each constituent group; USFS, U.S. Forest Service; EPA, U.S. 

Protection Agency; ODEQ, Oregon Department of Environmental Quality; USGS, U.S. Geological Survey; NA, not available; s

EPA’s STOrage and RETrieval System, USGS’s National Water Inventory System, Tetra Tech, Inc., 1993; and Tetra Tech, Inc

Washington, unpub. data, 1994]

Site number Site name Sampling agency Number of

data values

Major Ions

4527001220900 Bull Run Reservoir at Headworks USFS, EPA 12,647

4526001220200 Fox Creek USFS 10,026

4533491224317 Willamette S.I. Monitor EPA 6,310

4527001220700 South Fork at S-111 USFS 3,418

4534461224442 Willamette River at SP&S Railroad Bridge NA 3,253

Water Temperature and pH

4527001220900 Bull Run Reservoir at Headworks USFS, EPA 24,273

4530001220300 Cougar Creek/ Deer Creek at S-10 USFS 6,081

4533491224317 Willamette S.I. Monitor EPA 5,875

4527001220700 South Fork at S-111 USFS 4,875

4530001225400 Otter Creek/ Log Creek/ Blazed Alder Creek USFS 4,699

Dissolved Oxygen

4527001220900 Bull Run Reservoir at Headworks USFS, EPA 10,950

4533491224317 Willamette S.I. Monitor EPA 5,694

4534411224451 Willamette River at SP&S Railroad Bridge ODEQ 1,958

4534461224442 Willamette River at SP&S Railroad Bridge NA 1,917

4456521230242 Willamette River at Salem Railroad Bridge ODEQ 1,721

Nutrients

4526001220200 Fox Creek USFS 2,993

14211720 Willamette River at Portland USGS 935

452481225103 Tualatin River at Elsner Road Bridge NA 864

14207500 Tualatin River at West Linn USGS 784

14128910 Columbia River at Warrendale USGS 774

Trace Elements

14128910 Columbia River at Warrendale USGS 2,115

14211720 Willamette River at Portland USGS 1,964

14207500 Tualatin River at West Linn USGS 1,815

14247400 Columbia River at Bradwood USGS 763

4524181225103 Tualatin River at Elsner Road Bridge NA 587

Organic Compounds

14202000 Pudding River at Aurora USGS 4,384

14201300 Zollner Creek near Mt. Angel USGS 4,228

14206950 Fanno Creek at Durham USGS 2,008

14211720 Willamette River at Portland USGS 1,122

4431381231209 Muddy Creek near Peoria USGS 800

Suspended Sediment

4526001220200 Fox Creek USFS 2,868

4530001220200 North Fork Bull Run at RM 0.1 above S-10 USFS 2,022

4529001220100 Fir Creek at S-111 USFS 1,991

4527001220900 Bull Run Reservoir at Headworks USFS, EPA 1,766

4530001220000 Bull Run Main stem/ Bear Creek West Fork USFS 1,689

Bacteria

14138990 Bear Creek near Bull Run USGS 329

14138900 North Fork Bull Run River near Multnomah Falls USGS 322

14138960 Cougar Creek near Bull Run USGS 322

14138950 Deer Creek near Bull Run USGS 319

14138850 Bull Run River near Multnomah Falls USGS 316

14139800 South Fork Bull Run River near Bull Run USGS 316
24

The major ions, water temperature and pH,

dissolved oxygen, and nutrient groups had the

largest number of determinations, probably because

these constituents (1) are the least costly to

determine, (2) can provide a good preliminary

indication of water-quality conditions, (3) are

associated with other water-quality concerns, and

(4) have methods of determination (with appropriate

reporting limits) that have been available for the last

couple of decades. In contrast, the potentially toxic

constituent groups, including the trace elements and

organic compounds, have fewer determinations,

primarily due to the high costs of determination and

shorter periods of record.

CONSTITUENT GROUP AND YEARS OF RECORD

0

220

20

40

60

80

100

120

140

160

180

200

NUMBER OF DETERMINATIONS, IN THOUSANDS

ALL OF THE LOWER COLUMBIA

RIVER BASIN

WILLAMETTE RIVER BASIN ONLY

MAJOR IONS

1947-1993

WATER TEMPERATURE

AND pH, 1939-1993

DISSOLVED OXYGEN

1939-1993

NUTRIENTS

1064-1993

TRACE ELEMENTS

1951-1993

ORGANICS

1965-1993

SUSPENDED SEDIMENT

1969-1993

BACTERIA

1975-1993

Figure 13. Number of historical surface-water-quality

determinations by constituent group, lower Columbia River

Basin, Oregon and Washington, 1939-93. (Sources of data:

U.S. Environmental Protection Agency’s STOrage and

RETrieval System; U.S. Geological Survey’s National

Water Inventory System; Tetra Tech, Inc., 1993; and Tetra

Tech, Inc., Redmond, Washington, unpub. data, 1994.)

Current Data

The USGS, WDOE, and ODEQ collect

in the lower Columbia River Basin for the B

ambient-monitoring program from January t

December 1994 (table 7). All USGS data fro

study are published in the U.S. Geological S

Water Resources Data Report for Oregon for 

1994 water year (U.S Geological Survey, 19

USGS data also are available in the NWIS d

All data for this study collected by the USG

WDOE, and ODEQ will be stored in EPA’s S

database.

U.S. Geological Survey

Ten sites were sampled by the USGS in 

(fig. 14). The location of each site was deter

by comparing landmarks in the field to 7–1/2 

series topographic maps (scale 1:24,000). A

sampling, field measurements (dissolved oxy

pH, water temperature, alkalinity, and specif

conductance) were made and samples were c

for determination of major ions, nutrients,

suspended sediment (concentration and perc

than 63 μm [micrometers]), fecal-indicator b

and chlorophyll. At each of the 10 sites, 4 sa

were made for trace elements and organic

compounds. Analyses included measuremen

trace elements in filtered water and in suspe

sediment, organic compounds in filtered wat

organic carbon in filtered water and associat

suspended sediment. Sample collection date

not based on hydrologic events, but were sch

in advance, as is consistent with a basic mon

program. Additional samplings for organic

compounds were made at the Willamette Riv

part of the USGS Willamette NAWQA and

Willamette State Study sampling program. S

10 sites were sampled monthly by boat: the 

Columbia River sites, the Willamette River a

Portland, and Multnomah Channel near mou

tables were consulted at tidally affected site

facilitate sampling during ebb tides and to in

that samples represented water-quality cond

upstream. The other four sites (the Sandy Ri

4The term “filtered water” is an operational definitio

to the chemical analysis of that portion of a water-suspend

ment sample that passes through a nominal 0.45-μm (0.70

organic compounds) filter. The term “unfiltered water” re

chemical analysis of a water sample that has not been filte

trifuged, nor in any way altered from the original matrix.
Table 7. Sampling sites and constituents analyzed, lower Columbia River Basin, Oregon and Washington, 1994

[USGS, U.S. Geological Survey; ODEQ, Oregon Department of Environmental Quality; WDOE, Washington Department of Ecology; NA, not applicable; SS, suspendeCh, chlorophyll; TSS, total suspended solids; sites may be referred to by their abbreviated name in this report]

Agency

site

number

Site name

(abbreviated site name) Agency

River mile Number of samp

Columbia Tributary 

Field values Major ions Nutrients

14128910 Columbia River at Warrendale, Oregon

(Warrendale)

USGS 141.0 NA 11 11 11 

453056122213701

Sandy River near Troutdale, Oregon(Sandy River)

USGS 120.5 5.8 4 4 4 

402351 Sandy River at Troutdale, Oregon ODEQ 120.5 3.1 13 0 13 14144710 Columbia River at river mile 102, downstream of Hayden

Island, Oregon(Hayden Island)

USGS 102.0 NA 14 13 13 

14211720 Willamette River at Portland, Oregon

(Willamette River)

USGS 101.5 12.8 14 14 14 

402288 Willamette River at Hawthorne Bridge, Oregon ODEQ 101.5 13.2 14 14 14 455417122441000

Lewis River at Woodland, Washington(Lewis River)

USGS 87.0 5.7 4 4 4 

27C070 Lewis River at Woodland, Washington WDOE 87.0 5.7 12 0 12 14222850 Multnomah Channel near mouth, at St. Helens, Oregon

(Multnomah Channel)

USGS 86.3 .9 12 12 12 

14222890 Columbia River near Columbia City, Oregon

(Columbia City)

USGS 82.4 NA 12 12 12 

14223600 Kalama River above Spencer Creek, near Kalama,

Washington(Kalama River)

USGS 73.1 2.8 4 4 4 

27B070 Kalama River near Kalama, Washington WDOE 73.1 2.8 12 0 12 14244200 Cowlitz River at Kelso, Washington

(Cowlitz River)

USGS 68.0 4.8 4 4 4 

26B070 Cowlitz River at Kelso, Washington WDOE 68.0 4.8 12 0 12 14246900 Columbia River at Beaver Army Terminal near Quincy,

Oregon(Beaver Army Terminal or Beaver)

USGS 53.8 NA 16 17 16 
26

Figure 14. Map showing U.S. Geological Survey sampling locations, lower Columbia River Basin, Oregon and Washington, 1994.
27

Lewis River, Kalama River, and Cowlitz River)

were sampled from bridges; each sites was sampled

four times during 1994.

Sampling techniques described by Edwards

and Glysson (1988) were used to insure that the

sample was representative of the flow in the cross

section. Samples were obtained either at equal

spacing across the cross section (equal-widthincrement method), or at the centroids of equaldischarge increments (equal-discharge-increment

method). Samples were collected by using a

weighted sampler designed to fill with water

isokinetically (at the same rate as the flow velocity

of the river). The sampler was lowered to the river

bed (up to 80 feet deep) and raised by using a

variable-speed power-operated winch. For the boat

sites, an 8-liter (L) collapsible Teflon-bag sampler

with Teflon cap and nozzle (C.F. Nordin, U.S.

Geological Survey, written commun., 1981) was

used following the procedures outlined by Meade

and Stevens (1990) and Horowitz and others (1994).

Alternatively, an epoxy-coated aluminum sampler

(the D-77 depth-integrating sampler), which

contained a 3-L Teflon bottle with Teflon cap and

nozzle, was used at the bridge sites. Samples for

bacterial analysis were collected from the

midchannel section by using an autoclaved plastic

bag in the sampler and a sterilized cap and nozzle.

Field measurements were made by using a portable

probe unit at a depth of 1 meter at 10 locations

along the cross section. These measurements were

recorded as the arithmetic mean of the 10

measurements. At the Columbia River sites, total

dissolved gas was measured in June and July by

using a Weiss saturometer.

The parts-per-billion protocol described by

Horowitz and others (1994) was followed for the

collection of samples for trace-element analysis of

filtered water. This procedure involves acid rinsing

or acid soaking the sampler and sample containers

and the use of latex gloves by a person who touches

only the sampler. Samples for trace elements, major

ions, nutrients, suspended sediment, and

chlorophyll were transferred from the sampler to a

14 L polyethylene churn splitter. Samples for

organic compounds were transferred to a 10 L glass

carboy, and samples for trace elements in suspended

sediment were transferred to 10 L polycarbonate

carboys. Bacteria samples were transferred to

sterilized glass bottles. All samples were chilled

immediately in the field, except for suspend

element samples for which the large volume 

120 L) made immediate chilling impractical

sample volumes were needed for suspended 

elements, because the suspended sediment

concentration in the Columbia River was oft

low as 5 to 10 mg/L. On a monthly basis, qu

assurance samples were included with routin

quality samples to quantify accuracy, precisi

presence of laboratory contamination, and an

bias. The quality assurance program consiste

source solution blanks, field equipment blan

samples, standard reference samples, and for 

compounds only, field matrix spikes and sur

spikes. Results of the quality assurance progr

included in the quality assurance section at t

of this report.

Equipment used for sampling and proce

was washed with Liquinox, rinsed with hot t

water, once with 5-percent (by volume) hydr

acid, and three times with distilled/deionize

The Teflon sample bottles and the filtration u

for organic compounds also were rinsed with

methanol and allowed to air dry. The organic

filtration unit was instead rinsed with organi

blank water. All sampling equipment was rin

ambient stream water prior to sample collec

At the USGS laboratory in Portland, w

samples were processed immediately and pr

for laboratory analysis. The churn splitter w

to resuspend the water/sediment mixture pri

subsampling for unfiltered-water determinat

Before filtered-water samples were processe

of the water-suspended sediment mixture wa

withdrawn from the churn splitter into a gra

cylinder for organic-carbon analysis. The m

was filtered through a 47-mm (millimeter) d

0.45-μm pore-size silver filter. The filtrate f

analysis of organic carbon in filtered water w

collected in a 125-mL (milliliter) glass bottl

Teflon lid-liner. The silver filter was remove

the filter assembly and placed in a petri dish 

analysis of organic carbon associated with s

pended sediment. A portion of the water rem

in the churn splitter was filtered through a 0

pore-size capsule filter and dispensed into th

corresponding sample bottles for filtered-wa

determinations. Filtered-water samples for t

elements were preserved with ultrapure nitri

according to Horowitz and others (1994). Fi
28

water samples for mercury were preserved with

nitric acid/potassium dichromate. Nutrient samples

were preserved with mercuric chloride. The samples

for organic compounds were filtered through a

142-mm diameter, 0.7-μm pore-size glass-fiber

filter that had been baked to remove the organic

carbon. These filtered samples then were pumped

through solid-phase extraction cartridges, which

were submitted for analysis. All samples were

shipped on ice to the USGS National Water Quality

Laboratory (NWQL) in Denver, Colorado.

The samples for trace elements in suspended

sediment were refrigerated at 4°C on arrival at the

Portland laboratory. Within 1 week of collection,

the samples were brought to room temperature and

centrifuged to concentrate the suspended sediment.

Centrifuge speed and spin times were adequate to

remove 0.45-μm diameter or larger particles—

assuming a particle density of 2.5 grams per cubic

centimeter. Each sample was rinsed in approximately 250 mL of distilled/deionized water during

the final centrifugation steps. Final sample

concentrates were placed in the oven at room

temperature until dry. The dried samples were

shipped to the USGS Analytical Chemistry Services

Group in Denver, Colorado, for analysis.

Bacteria samples were analyzed by membranefiltration methods according to Britton and Greeson

(1987) and the American Public Health Association

and others (1989) at the USGS’s Portland

laboratory. Chlorophyll samples were analyzed

using fluorometry (American Public Health

Association and others, 1989) at the USGS’s

Portland laboratory. Samples for suspendedsediment concentration and size class were

analyzed at the USGS laboratory in Vancouver,

Washington, using the methods in Guy (1969).

Table 8 lists the major ions, nutrients, organic

carbon, and trace elements determined at the USGS

National Water Quality Laboratory. Water samples

were analyzed for major ions according to methods

of Fishman (1993) and Fishman and Friedman

(1989). Nutrients were analyzed according to

methods of Fishman (1993), Kim Pirkey, (USGS,

written commun., 1995), and Patton and Truitt

(1992). Organic carbon was analyzed according to

the methods described in Brenton and Arnett

(1993), and Wershaw and others (1987). Filteredwater samples for all trace elements except arsenic,

selenium, and mercury were analyzed by

inductively coupled plasma-mass spectrome

described in Faires (1993). Arsenic and sele

were analyzed by hydride generation-atomic

absorption spectrometry, and mercury was a

by cold vapor-atomic absorption spectromet

(Fishman and Friedman, 1989).

The method reporting limits (MRL’s) s

table 8 are based on reliable quantification, 

various sample compositions. The purpose o

MRL’s rather that method detection limits is 

minimize the problems associated with field 

laboratory contamination and to ensure a hig

degree of confidence in analytical results fro

routine mode of operation. For trace elemen

filtered water, the MRL’s are approximately 

times greater than the average-determined m

detection limit (Faires, 1993).

Organic compounds in filtered water w

analyzed at the NWQL by gas chromatograp

spectrometry after eluting the analytes from 

18 solid-phase extraction cartridge as descri

Zaugg and others (1995). Table 9 lists the 47 

compounds analyzed using this method (sch

2010). The method detection limits (MDL) f

schedule 2010 are listed in table 9. The MD

represent the minimum analyte concentration 

in a sample with a given composition contai

analyte that can be identified, measured, and

reported with 99-percent confidence that the 

concentration is greater that zero.

In addition to determinations of the 47 

compounds listed above, a second group of 4

organic compounds was analyzed by using h

performance liquid-chromatography/ultravio

spectrometry. Quality assurance for this new 

(designated by the USGS as schedule 2051) 

review by the USGS’s Methods Developmen

The USGS is reviewing analytical-method

performance issues related to sample preserv

sample degradation, potential for saturation 

Carbopak solid-phase adsorbent cartridge an

subsequent loss of analyte prior to analysis, 

time between sample extraction from the soli

cartridge and sample analysis, potential for

coelution of analytes, and concerns regardin

negatives. All of these factors ultimately aff

quality of the reported organic-compound

concentrations. Consequently, schedule 205

were unavailable for use in this study
29

Table 8. Method reporting limits for major ions, nutrients, organic carbon, and trace elements analyzed in filtered 

unfiltered water, lower Columbia River Basin, Oregon and Washington, 1994

[Values are reported in milligrams per liter, except for trace elements which are reported in micrograms per liter; STORET, U.S. Environme

Agency’s STOrage and RETrieval system; method reference numbers correspond to:

a. Fishman, 1993, d. Patton and Truitt, 1992,

b. Fishman and Friedman, 1989, e. Brenton and Arnett, 1993,

c. Kim Pirkey, U.S. Geological Survey National Water Quality f. Wershaw and others, 1987, and

 Laboratory, written commun., 1995 g. Faires, 1993 ]

STORET code Constituent name Method reference number Method reportin

Major ions in filtered water

00915 Calcium a. I-1472-87 0.02

00940 Chloride b. I-2057-85 .1

00950 Fluoride b. I-2057-85 .1

01046 Iron a. I-1472-87 .003

00925 Magnesium a. I-1472-87 .01

00935 Potassium b. I-1630-85 .1

00955 Silica a. I-1472-87 .01

00930 Sodium a. I-1472-87 .2

00945 Sulfate b. I-2057-85 .1

70300 Total dissolved solids b. I-1750-85 1

Nutrients in water

00608 Ammonia as N, filtered water a. I-2522-90 .01

00623 Ammonia plus organic nitrogen as N, filtered water c. I-2515-91 .2

00625 Ammonia plus organic nitrogen as N, unfiltered water c. I-4515-91 .2

00613 Nitrite as N, filtered water a. I-2540-90 .01

00631 Nitrite plus nitrate as N, filtered water a. I-2545-90 .05

00671 Orthophosphate as P, filtered water a. I-2601-90 .001

00666 Phosphorus as P, filtered water d. I-2610-91 .01

00665 Phosphorus as P, unfiltered water d. I-4610-91 .01

Organic carbon in water

00681 Organic carbon, filtered water e. O-1122-92 .1

00689 Organic carbon, associated with suspended sediment f. O-7100-83 .1

Trace elements in filtered water

01106 Aluminum g. I-2477-92 1

01095 Antimony g. I-2477-92 1

01000 Arsenic b. I-2062-85 1

01005 Barium g. I-2477-92 1

01010 Beryllium g. I-2477-92 1

01025 Cadmium g. I-2477-92 1

01030 Chromium g. I-2477-92 1

01035 Cobalt g. I-2477-92 1

01040 Copper g. I-2477-92 1

01049 Lead g. I-2477-92 1

01056 Manganese g. I-2477-92 1

71890 Mercury b. I-2462-85 .1

01060 Molybdenum g. I-2477-92 1

01065 Nickel g. I-2477-92 1

01145 Selenium b. I-2667-85 1

01075 Silver g. I-2477-92 1

22703 Uranium g. I-2477-92 1

01090 Zinc g. I-2477-92 1
30

Table 9. Method detection limits for organic compounds analyzed in filtered water, lower Columbia River Basin, Oregon 

Washington, 1994

[The term “filtered water” is an operational definition referring to the chemical analysis of that portion of a water-suspended sediment sample that p

a nominal 0.70-micrometer filter; values are reported in micrograms per liter; STORET, U.S. Environmental Protection Agency’s STOrage and RET

DCPA, 3’,4’-dichloropropionanilide; DDE, dichlorodiphenyldichloroethylene; EPTC, S-ethyl dipropyl thiocarbamate; HCH, hexachlorocyclohexa

discussed in Zaugg and others, 1995]

STORET code Compound name Chemical Abstracts Services

 registry number Method detection limit

49260 Acetochlor 34256-82-1 0.009

46342 Alachlor 15972-60-8 .002

39632 Atrazine 1912-24-9 .001

82686 Azinphos-methyl 86-50-0 .001

82673 Benfluralin 1861-40-1 .002

04028 Butylate 2008-41-5 .002

82680 Carbaryl 63-25-2 .003

82674 Carbofuran 1563-66-2 .003

38933 Chlorpyrifos 2921-88-2 .004

04041 Cyanazine 21725-46-2 .004

82682 DCPA 1861-32-1 .002

34653 4,4’-DDE 72-55-9 .006

04040 Deethylatrazine 6190-65-4 .002

39572 Diazinon 333-41-5 .002

39381 Dieldrin 60-57-1 .001

82660 2,6-Diethylaniline 91-66-7 .003

82677 Disulfoton 298-04-4 .017

82668 EPTC 759-94-4 .002

82663 Ethalfluralin 55283-68-6 .004

82672 Ethoprop 13194-48-4 .003

04095 Fonofos 944-22-9 .003

34253 alpha-HCH 319-84-6 .002

39341 gamma-HCH (lindane) 58-89-9 .004

82666 Linuron 330-55-2 .002

39532 Malathion 121-75-5 .005

82667 Methyl parathion 298-00-0 .006

39415 Metolachlor 51218-45-2 .002

82630 Metribuzin 21087-64-9 .004

82671 Molinate 2212-67-1 .004

82684 Napropamide 15299-99-7 .003

39542 Parathion 56-38-2 .004

82669 Pebulate 1114-71-2 .004

82683 Pendimethalin 40487-42-1 .004

82687 cis-Permethrin 52645-53-1 .005

82664 Phorate 298-02-02 .002

04037 Prometon 1610-18-0 .003

82676 Pronamide 23950-58-5 .018

04024 Propachlor 1918-16-7 .007

82679 Propanil 709-98-8 .004

82685 Propargite 2312-35-8 .013

04035 Simazine 122-34-9 .005

82670 Tebuthiuron 34014-18-1 .010

82665 Terbacil 5902-51-2 .007

82675 Terbufos 13071-79-9 .007

82681 Thiobencarb 28249-77-6 .002

82678 Triallate 2303-17-5 .001

82661 Trifluralin 1582-09-8 .002
31

Suspended trace elements were analyzed at the

USGS Analytical Chemistry Services Group in

Denver for 44 trace elements (table 10).Most of the

elements were analyzed by inductively coupled

plasma-atomic emission spectrometry following

multi-acid sample decomposition (Briggs, 1990).

Alternatively, nine elements (antimony, arsenic,

cadmium, lead, molybdenum, silver, thallium,

thorium, and uranium) were analyzed by

inductively coupled plasma-mass spectrometry

following multi-acid sample decomposition

(Briggs, 1990). Mercury was analyzed by

continuous flow cold vapor-atomic absorption

spectrometry following sample digestion with nitric

acid and sodium dichromate (O’Leary and o

1990). Selenium was analyzed by hydride

generation-atomic absorption spectrometry

following multi-acid digestion (Welsch and 

1990; Crock and Lichte, 1982). About 0.5 g

suspended sediment was necessary to perform 

analyses. On several occasions, especially in

samples from the four smaller tributaries, th

not enough suspended sediment to perform t

analyses for mercury and selenium.

Washington Department of Ecology

From February 1994 to December 1994

WDOE sampled the following three sites fro

Table 10. Method reporting limits for trace elements analyzed in suspended sediment, lower Columbia 

Basin, Oregon and Washington, 1994

[Values are reported in micrograms per gram unless otherwise noted; STORET, U.S. Environmental Protection

Agency’s STOrage and RETrieval system; %, percent; --, no code available for thallium; methods discussed in

Briggs, 1990, O’Leary and others, 1990, Welsch and others, 1990, and Crock and Lichte, 1982]

STORET

code

Element

name

Method reporting

limit

STORET

code

Element

name

Method reporting

limit

30221 Aluminum 0.005% 29841 Mercury 0.02

29816 Antimony .1 29843 Molybdenum.1

29818 Arsenic .1 35037 Neodymium 9

29820 Barium 1 29845 Nickel 3

29822 Beryllium 1 35038 Niobium 4

35030 Bismuth 10 30292 Phosphorus .005%

29826 Cadmium .1 30294 Potassium .01%

30240 Calcium .005% 35039 Scandium 2

35051 Cerium 5 29847 Selenium .2

29829 Chromium 2 29850 Silver .1

35031 Cobalt 2 30304 Sodium .006%

29832 Copper 2 35040 Strontium 2

35032 Europium 2 35042 Tantalum 40

35033 Gallium 4 -- Thallium .1

82170 Gold 8 35043 Thorium 6

35035 Holmium 4 35044 Tin 5

30269 Iron .02% 30317 Titanium .005%

35036 Lanthanum 2 35046 Uranium .07

29836 Lead .25 29853 Vanadium 2

35050 Lithium 2 35048 Ytterbium 1

30277 Magnesium .005% 35047 Yttrium 2

29839 Manganese 4 29855 Zinc 2
32

bridges about once a month: the Lewis River at

Woodland, Kalama River near Kalama, and Cowlitz

River at Kelso (table 7). Each site that the WDOE

sampled was at exactly the same location as the

corresponding USGS site. Temperature and specific

conductance were measured by lowering a probe

into the main channel, whereas measurements of pH

and dissolved oxygen were made on a near-surface

grab sample of water. Depth- and width-integrated

water samples were collected by lowering a US DH59 depth-integrating sampler at 10 equidistant

points along a transect across the river (Edwards

and Glysson, 1988). Each volume of water collected

was composited into an acid-washed Nalgene

container and agitated before individual subsamples

were poured into containers prepared for each

particular analysis. Water for nutrient analysis was

filtered in the field through a 0.45-micrometer

membrane filter (Bill Ehinger, WDOE, written

commun., 1995). The samples were shipped to

WDOE Environmental Laboratory in Manchester,

Table 11. Laboratory analytical methods and reporting limits for Washington Department of Ecology, lower Columb

Basin, 1994

[Values are reported in micrograms per liter for nutrients, milligrams per liter for solids, and colonies per 100 milliliters for bacteria; STORET

Environmental Protection Agency’s STOrage and RETrieval system; --, not available; information obtained from Bill Ehinger, Washington De

of Ecology; method reference numbers correspond to:

a. U.S. Environmental Protection Agency, 1979,

b. American Public Health Association and others, 1992, and

c. Valderrama, 1981]

STORET

code Constituent name Method of determination

Method

reference

number

Metho

reporti

limit

Nutrients in water

00610 Ammonia as N, unfiltered water Automated phenate a. 350.1

b. 4500-NH3 D

10

00630 Nitrite plus nitrate as N, unfiltered water Automated cadmium reduction a. 353.2

b. 4500-NO3F

10

00600 Nitrogen, unfiltered water Persulfate digestion, cadmium reduction c. 25

00671 Orthophosphate as P, filtered water Ascorbic acid a. 365.3

b. 4500-PF

10

00665 Phosphorus as P, unfiltered water Persulfate digestion, ascrobic acid a. 365.3

b. 4500-PF

10

Solids in water

00500 Total dissolved solids, filtered water -- a. 160.3

b. 2540B

1

00530 Suspended solids, unfiltered water Gravimetric a. 160.1 1

Bacteria

31616 Fecal coliform Membrane filter b. 9222D 1

Washington, where they were analyzed for n

suspended solids, and fecal-indicator bacteri

11).

Oregon Department of Environmental Qu

From January 1994 to December 1994, 

ODEQ sampled the Willamette River and th

River each month. Even though the ODEQ

Willamette River site was 0.4 miles upstream 

USGS site and the ODEQ Sandy River site w

miles downstream of the USGS site (table 7

from the corresponding sites were grouped t

with USGS data for analysis. The midpoint 

river was sampled from a bridge using a wei

stainless-steel grab sampler. Field measurem

were made of dissolved oxygen, pH, water

temperature, alkalinity, and specific conduct

Samples were collected and field measureme

were made according to ODEQ protocols, an

laboratory analyses were performed in the O
33

laboratory in Portland, Oregon (Greg Pettit, ODEQ,

written commun., 1995).

Samples were analyzed for major ions

(Willamette River site only), nutrients, and fecalindicator bacteria. Ammonia plus organic nitrogen

in unfiltered water was analyzed by EPA Method

351.2, (U.S. Environmental Protection Agency,

1979), and phosphorus in unfiltered water and

orthophosphate in filtered water were analyzed by

Part 4500-P (American Public Health Association

and others, 1989). Bacteria samples were analyzed

by the Oregon Health Division, Office of Public

Health Laboratories in Portland. Enterococci were

analyzed by the membrane-filtration method, and

fecal coliform were measured by the most probable

number technique (American Public Health

Association and others, 1989).

Data-Analysis Methods

Two methods of data analysis that require

explanation and description are the estimation of

loads and the determination of trends over time,

which were calculated for several water-quality

constituents.

Loads

In this report, monthly and annual mean daily

loads were calculated using a regression model that

assumes a linear relationship between the natural

logarithm of concentration (log C) and the natural

logarithm of streamflow (log Q). The model was

created using the ESTIMATOR program, version

94.06 (Cohn and others, 1992). The ESTIMATOR

program regresses log C against log Q and the sine

and cosine of time (in decimal years, adjusted by

2π, for a yearly cycle) and generates equations for

calculating monthly and annual mean daily load

estimates. Monthly mean daily loads are the mean

of the individual daily mean loads for each month,

which the program computes, and annual mean

daily loads are the mean of the individual daily

mean loads for each year.

The ESTIMATOR program uses a minimum

variance unbiased estimator (Cohn and others,

1989), which reduces the bias introduced when

transforming load estimates from a log-regression

equation (log space) back into arithmetic units (real

space). The program also incorporates an adjusted

maximum likelihood estimator (Cohn, Gilro

Baier, 1992) to deal with censored data valu

which are values that are below a specified

“detection limit.” The ESTIMATOR program 

for use in hydrologic studies, because water 

data generally show a log-log relation and

commonly contain censored data. The ESTIM

program is widely used by the USGS, includ

35 current NAWQA studies. It is also used b

Maryland Department of the Environment on 

Chesapeake Bay projects, and by the U.S. A

Corps of Engineers.

The ESTIMATOR program is recomme

use with at least 25 water-quality measurem

year for 2 years. The Columbia River at War

and the Willamette River at Portland both ha

8 measurements per year for about 20 years, 

Columbia River at Beaver Army Terminal ha

measurements per year for 4 years. Although 

sites had fewer than recommended measurem

per year, the periods of available data are lon

recommended. The Willamette and Warrend

had much more than the 50 total recommend

measurements, and Beaver had nearly 50. N

sites in this study had data points in even clo

these numbers. Loads were estimated for fiv

constituents (suspended sediment, total diss

solids, phosphorus in unfiltered water, nitrit

nitrate in filtered water, and ammonia in filte

water) sampled at these three sites. Samples

generally were collected at different seasons 

year, rather than clustered during short perio

time. See table 12 for the number of data va

available for each constituent at each site.

The ESTIMATOR program uses daily m

streamflow data throughout the load comput

period. Streamflow data for the Willamette a

Beaver sites are available from the USGS stre

gaging program. Because the Warrendale sit

gaged, data for daily mean outflow from Bon

Dam, 5 miles upstream, were obtained from 

Army Corps of Engineers and used as daily 

flow at Warrendale. Three water years (1974

and 1977) were chosen from the 20-year loa

estimation period to represent years of high-

median-, and low-streamflow, respectively, b

annual mean streamflows at the Columbia R

mouth streamflow-gaging station. These yea

used to compare loads of the current year (1

low-, median-, and high-flow years in the pa
34

Although the loads estimated by this

regression model are believed to be the best

estimates given the available data sets, their

precision deserves some discussion. For each load

estimate, the ESTIMATOR program calculates the

standard error of prediction, from which a 95-

percent confidence interval can be derived. As an

example, if a load estimate of 200 tons per day has a

95-percent confidence interval of 20 percent, then

there is a 95 percent chance that the true load was

between 160 and 240 tons per day (200 ± 20

percent). Confidence intervals for annual mean

daily load estimates tended to be about one-half as

wide as intervals for monthly estimates. Table 12

shows the average 95-percent confidence intervals

for monthly and annual load estimates from the

ESTIMATOR program. The load estimates are most

reliable for total dissolved solids and less reliable

for other constituents (table 12). These differences

Table 12. Amount of water quality data available for load estimation program, and mean 95-percent confidence in

for load estimates at three sites in the lower Columbia River Basin, Oregon and Washington

[The term “filtered water” is an operational definition referring to the chemical analysis of that portion of a water-suspended sediment sample t

through a nominal 0.45-micrometer filter; conversely, the term “unfiltered water” refers to the chemical analysis of a water sample that has n

filtered or centrifuged, nor in any way altered from the original matrix; see table 7 for full site names]

Site name Years of data

available

Total number of

samples

Number of

censored

values

Mean 95-percent

confidence interval

for monthly

estimates

(percent of

estimate)

Mean 95-percent

confidence interva

for annual

estimates

(percent of

estimate)

Ammonia, filtered water

Willamette 1979-94 111 0 31 16

Warrendale 1973-94 80 14 63 33

Beaver 1990-94 49 7 43 24

Nitrite plus nitrate, filtered water

Willamette 1979-94 115 0 20 12

Warrendale 1979-94 86 22 29 16

Beaver 1990-94 49 8 51 36

Phosphorus, unfiltered water

Willamette 1974-94 173 0 18 9

Warrendale 1973-94 172 3 30 14

Beaver 1990-94 48 3 38 20

Suspended sediment

Willamette 1974-94 167 0 28 17

Warrendale 1973-94 164 0 44 21

Beaver 1990-94 49 0 24 12

Total dissolved solids, residue on evaporation at 180 degrees Celsius

Willamette 1974-94 171 0 4 2

Warrendale 1973-94 155 0 5 2

Beaver 1990-94 49 0 7 4

are due to the differing degrees by which the

constituent characteristics satisfy the assump

the regression model, particularly the linear 

between log C and log Q. The sampling stra

itself also affects the confidence intervals, be

was not designed to ensure sampling during 

flows. If more samples had been taken durin

flows, the confidence intervals would probab

been narrower.

Trends

A computer program called PT2 (Kenn

Lanfear, USGS, written commun., 1995) was 

determine monotonic-time trends in constitu

concentrations in the lower Columbia River 

This program uses the seasonal Kendall test 

water-quality trends (see Helsel and Hirsch 

for a description of the test). This distributio
35

test (based on the ranking of data values) uses a

modified form of Kendall’s tau to determine trends.

The seasonal Kendall test involves hypothesis

testing for trend detection. The null hypothesis is

that the variable of interest (for example,

constituent concentration) and its time of

observation are independent, which indicates no

trend (Smith and others, 1982). The chance of

making an error by rejecting the null hypothesis

when a trend actually does not exist is measured by

the probability level (ρ). For example, if ρ = 0.05,

then there is a 5-percent chance of falsely rejecting

the null hypothesis. For this study, trends with a ρ

less than or equal to 0.05 were considered

statistically significant.

 There are two criteria for evaluating the

suitability of water-quality data for trend testing.

First, the data must have nearly spanned the time

period selected for trend analysis. Second, for a

given seasonal frequency (trends made on the basis

of quarterly data, for instance), the beginning and

ending parts of the record must have contained

sufficient data such that most of the possible

number of pairwise comparisons (as made in the

seasonal Kendall test) were present for most of the

seasons. Owing to a lack of continuous data for

most sites, trend tests were performed only on data

from the Columbia River at Warrendale and

Willamette River at Portland sites (the two

historical NASQAN sites).

Seasonal patterns that may affect results from

trend analyses commonly are observed in waterquality data. For example, in the calculation of

long-term trends, data collected during an extreme

high-flow winter storm should not be compared to

data collected during a low-flow summer condition.

To minimize erroneous conclusions that could result

from these types of comparisons, data collected in

the same month of different years are compared (for

example, values from January 1993 are compared

with those from January 1994). When there are not

enough monthly data available, seasonal data can be

used. When the later constituent value (in time) is

larger, a plus is scored, but when lower, a minus is

scored (Smith and others, 1982). Equal numbers of

pluses and minuses indicate the absence of a trend.

When there are significantly more pluses than

minuses, an upward trend in constituent concentration is likely. In this nonparametric test, censored

data (values less than the reporting level) were

included in the analysis and set equal to the

reporting level.

Trends, unadjusted for streamflow, are

important because they represent changes in 

stituent concentrations that may affect water 

and biota. Because monthly data were not av

trend analysis was made using quarterly (Sep

October-November, December-January-Febr

and so on) constituent concentrations for da

collected from 1973 to 1995. For suspended

sediment data at the Willamette River at Por

however, there were enough data to use a bim

season (September-October, November-Dec

and so on).

To estimate the magnitude of the trend, 

seasonal slope estimator is computed (Hirsc

others, 1982). The slope estimator is the me

the data set containing the differences betwe

values collected in the same month (or quart

different years between the data. For examp

assume that the ammonia concentration at a 

0.1 mg/L (milligrams per liter) in the first qu

1993 and 0.2 mg/L in the first quarter of 199

difference between the values divided by the 

of years between the data is (0.2-0.1)÷(1994

= 0.1 mg/L per year. After computing these

differences for each quarter for all combinat

years, the slope (trend) is reported here as th

median change in the constituent value per y

slope (trend) also is reported in percent chan

year and is calculated as follows: (slope ÷ m

constituent value) × 100.

Trends in water quality are associated n

with fluctuations in climate and streamflow 

with human-caused changes in basin process

cluding land-use practices, point-source load

rates, and agricultural and forestry practices

adjustment procedures were used to determin

that are associated with changes in basin pro

These procedures deduce a relation between 

tration and streamflow and convert concentra

residual values before performing a trend tes

residual values. This procedure removes the

confounding effect of variations in streamflo

performs flow adjustment with a LOcally W

Scatterplot Smoothing (LOWESS) technique

(discussed by Helsel and Hirsch [1992]). It i

robust technique that provides a reasonably 

of concentration versus streamflow for a wid

variety of situations. The slope estimator is 
36

calculated from the flow-adjusted data to yield the

trends.

Existing Water-Quality Guidelines

Water-quality constituent concentrations

determined and physical measurements made in the

lower Columbia River Basin in 1994 were screened

to identify constituents and measurements that may

require further study by State and local health

agencies. These agencies are responsible for issuing

advice or formal advisories to protect the public

health. Major ion, nutrient, trace-element, and

organic-compound concentrations in filtered-water

samples are screened against EPA ambient waterquality criteria for the protection of aquatic life and

human health (U.S. Environmental Protection

Agency, 1995) and EPA primary drinking-water

regulations and human health advisories (U.S.

Environmental Protection Agency, 1994b). All EPA

ambient water-quality criteria are nonenforceable

guidelines that provide the basis for Oregon and

Washington State standards and are designed to

protect humans and aquatic organisms. The primary

drinking-water regulations have been established

for contaminants that are known to be present in

public water systems and that may affect human

health adversely (Nowell and Resek, 1994). Health

advisories provide nonregulatory levels of

contaminants in drinking water at which no known

or anticipated health effects would result. For some

constituents, the analytical detection limit is higher

than the lowest water-quality guideline.

Furthermore, guidelines are not available for

evaluation of all potential adverse effects

(specifically, acute and chronic toxicity to aquatic

organisms, human health effects as a result of

bioaccumulation in aquatic food organisms, and

exposure through drinking water).

Bioavailability and toxicity vary with the form

of a trace element (Jenne and Luoma, 1977).

Aquatic organisms that feed on detritus are exposed

to trace elements in solution and from the ingestion

of sediment (Luoma, 1989). Trace elements

associated with sediment generally are believed to

be less bioavailable than trace elements dissolved in

water (U.S. Environmental Protection Agency,

1992a). The toxicity to aquatic organisms from

trace elements associated with sediment, however,

is not necessarily zero. The concentrations of metals

in sediment often are orders of magnitude hi

than in water. Small geochemical changes in 

chemistry of sediment can affect solution ch

greatly and thus enhance bioavailability (Lu

1989). For example, trace elements associate

suspended sediment may dissolve in the che

environment of the gill or the gut of an aqua

organism (U.S. Environmental Protection Ag

1992a; Luoma, 1983).

Physical and microbiological measurem

were compared to water-quality regulations 

Oregon (State of Oregon, 1994) and Washin

(Washington State Administrative Code, 199

Washington streams are classified according 

general beneficial water uses. An antidegrad

policy is being used to protect existing water

conditions (Washington State Administrative 

1992). All of the Washington sites sampled 

study were at stream segments classified as 

(excellent), meaning that they must meet or 

standards established for all, or substantially 

designated water uses.

Ambient Stream Water Quality

Aquatic Life

According to EPA’s interim guidance o

aquatic-life criteria for trace elements (U.S.

Environmental Protection Agency, 1992a), t

toxicity tests that form the basis for EPA am

water-quality criteria for the protection of aq

life were generally conducted in water “low

metal-binding particulate matter and dissolv

organic carbon than most ambient waters * * 

[Therefore], these toxicity tests may oversta

ambient toxicity of nonbiomagnified metals 

interact with particulate matter or dissolved 

matter.” In metal toxicity tests on which wat

quality criteria were based, most of the meta

the dissolved form. However, because the ac

dissolved component was seldom measured 

tests, and because of the possible release of

dissolved metal from particulate forms, EPA 

are based on the total recoverable metal tech

This type of analysis for ambient stream wat

metal-binding phases, may extract trace elem

from the particulate or carbon phases, and

consequently, overstate ambient toxicity.

Although EPA’s ambient water-quality 

are based on analyses of unfiltered-water sam
37

the trace-element concentrations in filtered-water

samples analyzed for this report were often high

enough to equal or exceed the criteria.

Consequently, EPA’s ambient water-quality criteria

are used as screening values for the protection of

aquatic organisms. For many trace elements,

including cadmium, chromium, lead, nickel, silver,

and zinc, aquatic toxicity is related to the hardness

of the water; toxicity increases (the screening value

decreases) as hardness decreases. For example, as

water hardness ranges from 200 to 50 mg/L

(milligrams per liter) as calcium carbonate, lead

toxicity to aquatic organisms ranges from 7.7 to

1.3 μg/L (micrograms per liter) (U.S. Environmental Protection Agency, 1986a). For trace

elements with toxicity that varies with water

hardness, the ambient water hardness at the time of

sample collection was used to derive the appropriate

screening value. Both acute (1-hour average

concentrations) and chronic (4-day average

concentrations) trace-element criteria for aquatic

life were used to evaluate waters in the lower

Columbia River Basin; however, single measurements, rather than multiple measurements were

used to derive 1-hour or 4-day average traceelement concentrations.

Human Health

The ambient stream-water criteria for the

protection of human health consist of ambient

concentrations which, for noncarcinogens, prevent

adverse health effects in humans and, for suspected

or proven carcinogens, represent various levels of

incremental cancer risk. The human-health criteria

are designed to reflect human exposure to a

contaminant from ingestion of both water and

aquatic organisms or from ingestion of aquatic

organisms only (U.S. Environmental Protection

Agency, 1995). In the former, 100 percent of the

exposure to humans is assumed to be from

consumption of water containing a specified

contaminant concentration and aquatic organisms

that have biologically concentrated a contaminant

from ambient stream water according to an assumed

biological concentration factor (Nowell and Resek,

1994; U.S. Environmental Protection Agency,

1995). In the latter, 100 percent of the exposure to

humans is assumed to be from consumption of

aquatic organisms that have biologically

concentrated a contaminant from water according to

an assumed bioconcentration factor. Equations for

deriving ambient contaminant concentration

protection of human health are given by Now

Resek (1994).

For carcinogens, the human-health crite

derived from a two-part evaluation in which 

element is assigned a weight-of-evidence

classification and a slope factor. The weight

evidence classification is the likelihood that 

element is a human carcinogen. Arsenic, wh

measured in filtered-water samples, has a “G

weight-of-evidence classification—a human

carcinogen (U.S. Environmental Protection A

1989). The slope factor is generally a plausi

upper-bound estimate (95-percent confidenc

of a human developing cancer as a result of 

lifetime (70 years) of exposure to a particula

of a potential carcinogen. Slope factors are d

from mathematical models that are used on a

data sets. These models extrapolate from

carcinogenic responses observed at high dos

experimental animals to responses expected 

humans from lower exposure levels in the

environment. If the extrapolation model sele

EPA’s linearized-multistage model (as in the 

arsenic), then the resultant slope factor is kn

q1* (U.S. Environmental Protection Agency

For example, the slope factor or q1* for arse

1.75 risk per milligram contaminant per kilo

body weight per day (U.S. Environmental Pr

Agency, 1995).

The derivation of human-health criteria 

ambient stream water is contingent on sever

additional assumptions, which include:

Risk Level (RL) = A unitless assigned 

maximum-acceptable individual-lifetime ris

Screening values for human health are based 

of 10-5—a level of risk not to exceed one exc

of cancer per 100,000 individuals exposed o

year lifetime (U.S. Environmental Protection

Agency, 1993a).

Consumption Rate (CR) = Mean daily

consumption rate, in kilograms per day (kg/d

species of interest by the general population 

subpopulation of concern averaged over a 70

lifetime. Screening values for human health 

derived using a CR of 0.0065 kg/d—an estim

the average fish and shellfish consumption b

general United States population (U.S. Envi

mental Protection Agency, 1993a). The valu

equivalent to approximately one 6-ounce fill
38

fish per month. In addition, screening

concentrations that include a measure of chemical

uptake from the consumption of water use a CR of 2

L of water per day (L/d)—an estimate of the

average water consumption by the general United

States population.

Body Weight (BW) = Mean body weight, in

kg, of a standard adult within the general population

or subpopulation of concern. Screening values for

human health are derived using a BW of 70 kg

(about 154 pounds), the average weight of the

general United States population.

Biological Concentration Factor (BCF) = The

ratio of the contaminant concentration in an aquatic

organism, in milligrams per kilogram, to the

contaminant concentration in the surrounding water,

in mg/L, reported in units of liters per kg (L/kg). A

weighted-average BCF, adjusted to the average

percent lipids in fish and shellfish (3 percent), is

used by EPA in deriving human-health guidelines

(U.S. Environmental Protection Agency, 1995).

The screening value for arsenic is based on the

inorganic form only (U.S. Environmental Protection

Agency, 1992b). The arsenic determination in this

study, however, is based on both the organic and

inorganic forms of arsenic. As a conservative

assumption for screening, arsenic is assumed to

reside in ambient waters in the pentavalent and (or)

trivalent forms—the former being most likely in

surface water (Eisler, 1988, p. 8). Methylated forms

of arsenic also reside in surface water; their exact

proportions, however, are not known (Hem, 1989,

p. 144). Methylated forms are significantly less

toxic than inorganic forms of arsenic (U.S. Environmental Protection Agency, 1992b; U.S. Environmental Protection Agency, 1993b, p. III–56).

For noncarcinogens, the screening values are

based on a Reference Dose (RfD), rather than an

RL, which represents a daily exposure (with

uncertainty spanning perhaps an order of magnitude

or more) to the human population (including

sensitive subpopulations) that is probably without

appreciable risk of causing deleterious effects

during a 70-year lifetime (U.S. Environmental

Protection Agency, 1993a). Additionally, screening

values for human health, which are derived from

EPA ambient water-quality criteria for human

health, are determined using the assumptions for

BW, CR, and BCF listed above (U.S. Environmental

Protection Agency, 1995). For the purpose o

calculating screening values for mercury (a

noncarcinogen), the EPA recommends that t

for methylmercury be lowered from 3.0 × 10

mg/kg/d to 6.0 × 10-5 mg/kg/d (U.S. Environ

Protection Agency, 1993a). The lowering of 

is based on evidence that the fetus, and poss

pregnant woman, is at increased risk of adve

neurological effects from exposure to

methylmercury.

Under the usual conditions of temperat

pressure, mercury in surface water exists in

inorganic forms that include the liquid (Hgo) 

ionic (Hg2

+ and Hg2+) states. In addition, in

forms in sediment and water can be methyla

highly soluble and toxic methylmercury (Mo

1991). The analytical technique used in this 

for measuring mercury in ambient stream wa

defined as a total- (inorganic plus organic) m

analysis. For screening purposes, total-merc

concentrations are compared to the screenin

for human health. Using total-mercury conc

trations for comparison to screening values i

conservative, because 100 percent of the me

that accumulates in fish tissue (based on a B

5,500 L/kg) is assumed to be in the toxic me

mercury form. It is this methylated form of m

that is highly toxic to humans (U.S. Environ

Protection Agency, 1993a).

Drinking-Water Quality

Element concentrations determined fro

filtered-water samples were screened by mak

comparisons with EPA drinking-water regul

(U.S. Environmental Protection Agency, 199

EPA advisories for human health (U.S. Envi

mental Protection Agency, 1995). The water 

from the lower Columbia River Basin that ar

compared to drinking-water guidelines repre

untreated water (ambient stream water rathe

finished or treated water available for distrib

community water supplies). The City of Lon

diverts its water supply directly upstream fro

Cowlitz River sampling location, and the Ci

Kalama diverts just downstream from the sa

location on the Kalama River. Although nea

sites sampled in this study were not sources 

domestic-water supplies, water-quality exce

are important because the Washington sites a

stream segments classified as class A waters
39

important to note, however, that “although a surface

water in Washington State may be designated as a

potential domestic-water source” in Chapter 173–

201 in the Washington State Administrative Code

(1992), “approval for such use must first be

obtained from the Washington State Department of

Health following an evaluation of the water quality”

(Harriet Ammann, Denise Laflamme, and Glen

Patrick, Washington State Department of Health,

written commun., 1993). Thus, the presence in

filtered stream-water samples of elements in

concentrations that exceed screening values

(drinking-water regulations) does not indicate that

human health is directly at risk.

Regulations

The types of primary and secondary drinkingwater regulations set forth by the EPA include

Maximum Contaminant Levels (MCLs) and

Maximum Contaminant Level Goals (MCLGs)

(U.S. Environmental Protection Agency, 1991). The

MCLs represent achievable levels of drinking-water

quality that take into consideration health effects,

treatment feasibility, and aesthetic considerations.

The MCLGs are nonenforceable health goals that

are not expected to cause any adverse human-health

effects over a lifetime of exposure and include a

margin of safety.

Health Advisories

Concentrations of constituents in filtered-water

samples are screened for human-health effects by

making comparisons to human-health advisories for

drinking water (U.S. Environmental Protection

Agency, 1994b). Unlike the ambient water-quality

criteria, human-health advisories for drinking water

are based only on the consumption of domestic

water. In this study, however, ambient stream water

is used to screen for health effects. Additionally, the

aforementioned assumptions for BW (70 kg), CR (2

L/d of water), and RL (10-5) are applicable to

screening values for human-health advisories. For

the carcinogen arsenic, the human-health advisory

is a risk specific dose (RSD) associated with a

specified RL and is calculated from the q1* for

arsenic (Nowell and Resek, 1994). For the

noncarcinogen mercury, the human-health advisory

is a lifetime-health advisory which is equal to 20

percent of the drinking-water equivalent level

(DWEL). The DWEL is the highest lifetimeexposure level in drinking water, assuming 1

percent exposure from that medium, at whic

adverse noncarcinogenic health effects woul

expected to occur (Nowell and Resek, 1994)

ANALYSIS OF AVAILABLE

SURFACE-WATER-QUALITY DATA

This section of the report is organized i

topical water-quality sections, which include 

(1994) and historical analyses (1939–93) of 

temperature, dissolved oxygen and pH, total

dissolved gas, suspended sediment, nutrient

ions and related measures, trace elements, o

compounds, fecal-indicator bacteria, and

radionuclides. Exceedances of water-quality

guidelines by samples collected in the curren

study are discussed within the topical water-

sections that follow. Specific information pe

to the number of exceedances, sites with

exceedances, and criteria and guidelines use

derive screening values are in tables 47, 48, 

(at back of report).

Water Temperature

The principal factors controlling riverin

temperatures are energy-transfer processes. 

processes include radiation inputs (air tempe

which varies with elevation and latitude),

convection/advection (vertical and horizonta

mixing, which varies with stream velocity, d

and roughness of the stream channel), evapo

and inflow of water of different temperature

Riverine-water temperature is important in a

biological sense, because increased water

temperatures are known to increase biologic

activity, which in turn increases the metaboli

cold-blooded aquatic organisms (MacDonald 

others, 1991). High water temperature also c

affect the survival of salmonid eggs and juve

salmonids. The lethal-temperature limit for 

sockeye salmon is 13.5°C (MacDonald and o

1991, p. 74). Spawning coho and steelhead m

intolerant of temperatures exceeding 10°C.

Interspecies competition (for example warm

versus cold-water fishes) is dependent upon 

temperature (U.S. Environmental Protection 

1986a). Unsuitable water temperatures can l
40

disease outbreaks in migrating and spawning

salmonids (Bjornn and Reiser, 1991).

The distribution of daily mean water

temperatures was determined from continuous

temperature recording stations at 14 sites in the

lower Columbia River Basin. Periods of record at

the various sites ranged from as few as 2 years

(1968–69 WY) for the Columbia River at Prescott

to as many as 17 years (1975–92 WY) for the

Columbia River at Warrendale (table 13). The most

recent continuous temperature measurements were

made at the Columbia River at Beaver Army

Terminal.

The distribution of daily mean water

temperatures was generally uniform among sites in

the lower Columbia River (fig. 15). These findings

coincide with results from an earlier study by

Moore (1968), who profiled water temperatures of

the Columbia River from RM 928 to 53.5. Moore’s

Table 13. Water-quality sites that have continuous record of stream temperature, lower

Columbia River Basin, Oregon and Washington, 1968-94

[Computer retrieval of chemical data by either the U.S. Geological Survey’s (USGS) National Water Information

System (NWIS) or U.S. Environmental Protection Agency’s STOrage and RETrieval system (STORET) can be

made using the USGS site number]

USGS site

number Site name Period of record

14128910 Columbia River at Warrendale 1975-92

14144700 Columbia River at Vancouver 1968-70; 1973-79

14211720 Willamette River at Portland 1976-81

14211805 Willamette River above St. Johns Bridge 1972-75

14222880 Columbia River at Columbia City 1971

14222890 Columbia River near Columbia City 1969-72

14222910 Columbia River at Kalama 1969-79

14223780 Columbia River at Prescott 1968-69

14245295 Columbia River at Rainier 1972-79

14245300 Columbia River at Longview 1968-72

14246900 Columbia River at Beaver Army Terminal 1968-70; 1994-present

14247295 Columbia River at Wauna 1972-76

14247400 Columbia River at Bradwood 1977-81

14248600 Columbia River at Altoona 1972-79

temperature profiles show that the overall

temperature gradient from the Canadian bor

the mouth of the Columbia River was upwar

1966 through September 1967), with increas

ranging from 1 to 5°C per month from July t

August. However, the principal temperature

increases occurred well upstream of the low

Columbia River in an area between Coulee D

(RM 596.6) and McNary Dam (RM 292). On 

basis of monthly mean water temperatures f

period 1938–65, which includes effects of B

Reservoir on the Snake River and stepped-up

operations at Hanford (near RM 375), tempe

in the Columbia River at Bonneville Dam ex

20°C were measured as early as 1938. Addit

the mean monthly water temperature for Au

(21.1°C) for the 1938–65 period also exceed

at Bonneville Dam.

Streamflow in the Willamette River did 

significantly affect water temperature in the
41

Columbia River during the period July 1966 to

September 1967. On the basis of median (50thpercentile) daily mean water temperatures from

historical data analyzed in this study, the Willamette

River differed only slightly from the Columbia

River. Specifically, the 75th-percentile values at the

two Willamette River sites were slightly higher (by

0.4 to 0.8°C) than the 75th-percentile value

(17.8°C) in the Columbia River at Vancouver (fig.

15). A temperature gradient between the Willamette

River and the Columbia River during the summer

months may be expected; however, a gradient is not

noticeable due to the large difference in streamflow

in the two river systems. During a median

streamflow year (1967), the mean monthly

streamflow in the Willamette River at Portland for

the summer months (7,500 ft3/s) was about 4

percent of the mean monthly streamflow in the

Columbia River at Vancouver for the same time

period. The absence of a temperature gradient may COLUMBIA RIVER AT RAINIER (2,608)

0

5

10

15

20

25

30

WATER TEMPERATURE, IN DEGREES CELSIUS

EXPLANATION

Less than 1.5 times the

 interquartile range from

 the 75th percentile value

75th percentile

Median

25th percentile

Less than 1.5 times the

 interquartile range from

 the 25th percentile

Interquartile range equals the value

 of the 75th percentile minus the

 value of the 25th percentile.

COLUMBIA RIVER AT

WARRENDALE (5,788)

COLUMBIA RIVER NEAR

COLUMBIA CITY (1,386)

COLUMBIA RIVER AT

KALAMA (3,881)

COLUMBIA RIVER ATCOLUMBIA RIVER AT

PRESCOTT (362)

COLUMBIA RIVER AT

LONGVIEW (1,620)

COLUMBIA RIVER AT BEAVER

ARMY TERMINAL (642)

COLUMBIA RIVER AT

WAUNA (1,666)

COLUMBIA RIVER AT

BRADWOOD (1,691)

COLUMBIA RIVER AT

ALOONA (2,752)

WILLAMETTE RIVER AT

PORTLAND (2,063)

WILLAMETTE RIVER AT

ST JOHNS BRIDGE (1,321)

SITE NAME (NUMBER OF SAMPLES)

VANCOUVER (3,205)

COLUMBIA RIVER AT

COLUMBIA CITY (364)

Washington State Standard

Figure 15. Distribution of daily mean water temperatures in the lower Columbia River Basin, Oregon and Washingto

1968-94 water years.

also result from tidal flow reversals and the

associated mixing at the confluence of the tw

rivers.

The median daily mean water temperat

the lower Columbia River (1968–92 WY) an

Willamette River at Portland (1976–81 WY) 

highest during August (fig. 16). In the Colum

River at Bradwood (RM 38.9), for example, 

percent of the daily mean water temperature

81 WY) measured during August exceeded 2

only about 10 percent of the temperatures ex

20°C during the months of July and Septemb

(table 14).

Results of the seasonal Kendall trend te

water temperature indicate that significant (ρ 

upward trends exist in the Columbia River a

Warrendale and Willamette River at Portland 

50, at back of report). At Warrendale, the m

water temperature was 11.9°C, and the seaso
42

(153)

0

10

20

30

0

10

20

30

0

10

20

30

0

10

20

30

WATER TEMPERATURE, IN DEGREES CELSIUS

COLUMBIA RIVER AT WARRENDALE

COLUMBIA RIVER AT KALAMA

COLUMBIA RIVER AT BRADWOOD

WILLAMETTE RIVER AT PORTLAND

JAN FEB MAR APR MAY JUNE JULY AUG SEPT OCT NOV DEC

(175) (166)

(185) (173)

(183)

(164)

(181) (181)

(178)

(155)

(169)

(138) (141)

(155)

(150)

(155)

(124)

(124) (124) (120)

(155)

(150)

(155)

(277)

(287)

(339)

(303)

(334)

(330)

(336) (341)

(327)

(329)

(330)

(341)

(505) (454)

(520)

(485)

(527)

(496) (436) (443) (454)

(500)

(472)

(496)

EXPLANATION

Less than 1.5 times 

 interquartile range 

 the 75th percentile

75th percentile

Median

25th percentile

Less than 1.5 times 

 interquartile range 

 the 25th percentile

Interquartile range equals t

 of the 75th percentile min

 value of the 25th percenti

1.5 to 3 times the

 interquartile range 

 the 75th percentile

1.5 to 3 times the

 interquartile range 

 the 25th percentile

Washington State Standard

(505) Number of samples

Figure 16. Distribution of daily mean water temperatures in the Columbia River at Warrendale, Kalama, and Brad

and inthe Willamette River at Portland, lower Columbia River Basin, Oregon and Washington, 1975-92.
43

Table 14. Monthly distributions of daily mean water temperatures at selected sites, lower Columbia River Basin, O

and Washington, 1969-92

 [Values are reported in degrees Celsius; shaded numbers represent water temperatures that exceed the Washington State standard of 20 deg

Celsius (Washington State Administrative Code, 1992)]

Month Number of

measurements

Minimum

value

Value at indicated percentile Maximum

10 25 50 75 90 value

Columbia River at Warrendale, Oregon, 1976-92

 January 505 0.0 2.2 3.0 4.1 5.6 6.3 7.5

 February 454 .3 2.0 3.0 4.2 5.0 5.6 6.8

 March 520 3.3 4.7 5.4 6.2 7.1 7.7 9.9

 April 485 6.0 7.7 8.5 9.3 10.2 11.1 12.8

 May 527 9.5 10.9 11.9 12.9 13.7 14.4 16.2

 June 496 12.8 13.9 14.8 16.0 16.9 17.7 20.2

 July 436 16.0 17.3 18.1 19.2 20.1 20.5 22.1

 August 443 18.8 19.5 20.2 20.6 21.2 21.6 22.2

 September 454 15.2 17.3 18.3 19.2 20.1 20.8 21.7

 October 500 10.8 13.2 14.3 15.4 16.7 17.7 19.3

 November 472 3.3 8.1 9.5 11.0 12.2 13.0 15.2

 December 496 1.2 3.2 5.5 6.7 8.0 8.9 10.0

Columbia River at Kalama, Washington, 1969-79

 January 277 .0 1.9 2.8 4.0 4.8 5.2 8.7

 February 287 .0 2.0 2.9 3.8 4.8 5.5 6.2

 March 339 3.4 4.0 5.0 5.7 6.7 7.2 8.6

 April 303 5.7 7.0 7.9 8.8 9.6 10.3 13.0

 May 334 9.3 10.8 11.6 12.4 13.4 14.3 16.5

 June 330 12.6 13.7 14.4 15.7 16.8 18.0 19.6

 July 336 15.1 16.6 17.9 19.0 20.3 20.9 22.3

 August 341 18.5 19.5 20.0 20.5 21.1 21.8 23.2

 September 327 14.9 17.0 18.0 19.2 19.9 20.3 21.0

 October 329 10.5 13.0 13.8 14.9 16.0 17.0 18.2

 November 330 6.3 8.1 9.0 10.2 11.5 12.4 13.5

 December 341 1.4 4.7 5.4 6.4 7.2 8.0 9.0

Columbia River at Bradwood, Washington, 1977-81

 January 138 .0 0.7 2.4 3.8 5.4 6.0 7.7

 February 141 .0 2.0 3.2 4.3 5.3 6.1 6.5

 March 155 4.0 5.5 5.7 6.4 7.4 7.9 9.1

 April 150 7.1 7.9 8.7 9.5 10.3 10.9 12.3

 May 155 10.9 11.9 12.3 13.0 13.6 14.5 15.5

 June 124 13.1 14.3 15.1 16.2 16.7 17.6 18.5

 July 124 16.6 17.4 18.0 18.5 19.7 20.6 21.1

 August 124 18.8 19.6 20.2 20.8 21.2 21.6 22.3

 September 120 16.1 16.9 17.8 19.1 19.8 20.2 20.6

 October 155 12.6 13.6 14.3 15.3 16.9 17.6 18.9

 November 150 5.3 7.1 8.8 10.6 11.9 12.7 13.7

 December 155 2.8 4.8 5.7 6.6 7.5 7.9 8.7

Willamette River at Portland, Oregon, 1976-81

 January 175 0.1 2.5 4.2 5.6 6.9 7.6 9.0

 February 166 1.7 4.4 5.4 6.2 7.5 8.6 9.1

 March 185 5.7 6.8 7.5 8.4 9.5 10.2 13.0

 April 173 8.5 9.0 9.5 10.9 12.0 12.8 14.5

 May 183 10.7 12.2 13.0 13.7 14.5 15.5 16.8

 June 164 11.6 13.6 15.0 17.3 18.8 19.7 21.1

 July 181 18.0 18.9 19.8 20.7 21.9 23.2 25.7

 August 181 18.2 18.9 20.3 21.8 23.0 24.9 25.7

 September 178 14.7 15.9 17.0 18.5 19.2 19.8 21.2

 October 155 10.8 12.2 13.0 14.5 15.8 16.9 17.5

 November 169 4.7 6.3 8.0 9.1 11.0 11.7 13.0

 December 153 2.6 5.1 5.5 6.3 7.5 8.5 10.3
44

Kendall slope estimator shows that water

temperature has been increasing at a rate of 0.073°C

per year, which represents a 0.6-percent change in

the median water temperature per year. Data were

unavailable for calculating a flow-adjusted trend at

Warrendale. Both nonflow-adjusted and flowadjusted trends, however, were found in the

Willamette River. The median water temperature in

the Willamette River was 12.5°C, and the seasonal

Kendall slope estimator (nonflow-adjusted) shows

that water temperature has been increasing by

0.14°C per year which represents a 1.1-percent

change in the median water temperature per year.

The flow-adjusted trend is smaller, however,

representing only 0.9 percent of the median

temperature per year.

The instantaneous water temperatures

measured during July, August, and September,

1994, were generally similar at the main-stem sites

(fig. 17). During July and August temperatures

exceeded 20°C, and during September they were

nearly 20°C. The Willamette River generally was

the warmest tributary entering the main stem during

the July to September period—instantaneous water

temperatures were as high as 24.2°C. Conversely,

the Lewis River and the Kalama River were the

coldest tributaries entering the main stem during the

July to September period—instantaneous water

temperatures were as low as 14.3°C in the Lewis

River and 15.8°C in the Kalama River.

In this study, instantaneous water temperature

(for sites sampled in the lower Columbia River and

Washington tributaries) were evaluated against

water-quality standards for class A waters

according to the Washington State Administrative

Code (1992). The Code, which has special

conditions for the lower Columbia River (main

stem), states that freshwater-stream temperatures in

the lower Columbia River “* * * shall not exceed

20.0°C due to human activities * * *”; all other

freshwater-stream temperatures from Washington

waters designated as class A (the Lewis, Kalama,

and Cowlitz Rivers for this study) “* * * shall not

exceed 18.0°C due to human activity* * *.”

Temperature standards used by the State of

Oregon are not directly applicable to instantaneous

temperature measurements in ambient streamwater.

Rather, they were designed to regulate temperature

effects to rivers and streams from individual point

sources. For example, for the lower Willamette

Figure 17. Instantaneous water temperatures in the 

stem and tributaries of the lower Columbia River Ba

Oregon and Washington, July to September 1994. 

table 7 for full site names.)

14

26

16

18

20

22

24

MAINSTEM

TRIBUTARY

14

26

16

18

20

22

24

WATER TEMPERATURE, IN DEGREES CELSIUS

14

26

16

18

20

22

24

160 140 120 100 80 60 

RIVER MILE

JULY 1994

AUGUST 1994

SEPTEMBER 1994

Willamette River

Kalama Ri

Lewis River
45

River Basin (including Multnomah Channel), the

State of Oregon (1994) states that “No measurable

increases [in water temperature] shall be allowed

outside of the assigned mixing zone, as measured

relative to a control point immediately upstream

from a discharge, when stream temperatures are

70°F [21°C] or greater * * *.” Because individual

measurements of point-source water temperatures

were beyond the scope of this study, instantaneous

water temperatures in Oregon tributaries were not

evaluated relative to temperature standards.

The water temperatures in the main stem of the

lower Columbia River exceeded the Washington

water-quality standard (20°C) in 15 percent of the

samples (table 47, at back of report), including

consistent exceedances during July and August,

1994. This period coincides with seasonal high air

temperatures and low streamflows, is consistent

with historical water-temperature exceedances

(table 14), and reflects water temperature concerns

in the main stem of the lower Columbia River.

Dissolved Oxygen and pH

Most aquatic organisms require adequate

dissolved-oxygen concentrations and a suitable pH

range at all times. Anadromous cold-water fish are

particularly sensitive to the dissolved-oxygen

concentration and pH of fresh and marine waters.

The Oregon freshwater regulatory standard states

that dissolved oxygen should not be less than 90-

percent saturation in the Columbia River and not

less than 5 mg/L in the Willamette Harbor and

Multnomah Channel (State of Oregon, 1994). The

Washington standard states that dissolved-oxygen

concentrations should not be less than 90-percent

saturation in the Columbia River and should exceed

8 mg/L in Washington tributaries in the lower

Columbia River drainage (Washington

Administrative Code, 1992). Both agencies have

standards requiring that pH not be less than 6.5 or

greater than 8.5 for the lower Columbia River.

The solubility of oxygen in water is directly

proportional to the partial pressure of oxygen above

the water. The concentration of dissolved oxygen in

water at saturation decreases as barometric pressure

decreases (altitude increases) and (or) as water

temperature increases. In addition, oxygen

solubility decreases as the dissolved-solids content

increases. The concentration of oxygen can also be

changed by (1) aquatic plants producing oxy

product of photosynthesis, (2) aquatic organ

consuming oxygen as they respire, and (3) th

physical process of spilling water at dams, w

causes air bubbles to be entrained in the flow

(Wilhelms and Gulliver, 1994). Aquatic plan

cause dissolved-oxygen concentrations to sh

(over the 24 hours in a day) variability, with

maximum concentrations in the afternoon an

minimum concentrations in the early mornin

Dissolved-oxygen concentrations in the 

Columbia River Basin during 1994 are summ

in figure 18. Concentrations at all Columbia 

main-stem sites met the Oregon and Washin

dissolved-oxygen standards. The Washingto

tributary sites had no dissolved-oxygen

measurements that were below the Washingt

standard. The Oregon tributary, Sandy River 

Troutdale, had one dissolved-oxygen measu

below the Oregon State standard (table 47, at 

report). The Sandy River sample was measu

during August when water temperatures wer

and biological respiration was at a maximum

Examples of seasonal variability of dis

oxygen are shown in figures 19, 20, and 21. 

plots of data for the Columbia River at Warre

figure 19 indicate that there was minimal sea

variability of dissolved oxygen (in percent

saturation) for the 1974 to 1994 period. The 

data were typical of concentrations measured 

While there have been measurements of diss

oxygen concentrations that were below State

standards, they generally were infrequent, oc

less than 25 percent of the time. During Mar

through June and much of July, dissolved ox

Warrendale was usually supersaturated (abo

percent of saturation). This pattern is the res

spilling water at the Bonneville Dam and oth

upstream on the Columbia River (U.S. Army 

of Engineers, 1993).

Figure 20 shows dissolved-oxygen

concentrations in the Willamette River at Po

Figure 20a shows dissolved-oxygen concent

measured from 1949 through 1958, when me

concentrations during July, August, and Sep

did not meet the State standard of 5 mg/L.

Comparison of figures 20a and 20b (1972–9

indicates a significant increase in dissolved-

concentrations, which is likely the result of 

Army Corps of Engineers dams releasing wa
46

75

85

95

105

115

125

DISSOLVED OXYGEN, IN PERCENT SATURATION

WARRENDALE (10)

VANCOUVER (14)

COLUMBIA CITY (12)

BEAVER (16)

WILLAMETTE (30)

MULTNOMAH (12)

COWLITZ (15)

SANDY (18)

LEWIS (14)

KALAMA (14)

SITE NAME (NUMBER OF SAMPLES)

Oregon and Washington

State Standards

EXPLANATION

Less than 1.5 times the

 interquartile range from

 the 75th percentile

75th percentile

Median

25th percentile

Less than 1.5 times the

 interquartile range from

 the 25th percentile

Interquartile range equals the value

 of the 75th percentile minus the

 value of the 25th percentile.

1.5 to 3 times the

 interquartile range from

 the 75th percentile

1.5 to 3 times the

 interquartile range from

 the 25th percentile

Figure 18. Distribution of dissolved-oxygen concentrations, lower Columbia River Basin, Oregon and Washington, 1

table 7 for full site names; see State of Oregon [1994] and Washington State Administrative Code [1992] for standa

60

80

100

120

140

160

DISSOLVED OXYGEN, IN PERCENT SATURATION

Oregon State Standard JAN (12) FEB (10)

MAR (14)

APR (15)

MAY (17)

JUNE (13)

JULY (12)

AUG (17)

SEPT (10)

OCT (14)

NOV (14)

DEC (8)

YEARS 1974-94

EXPLANATION

Less than 1.5 times the

 interquartile range from

 the 75th percentile

75th percentile

Median

25th percentile

Less than 1.5 times the

 interquartile range from

 the 25th percentile

Interquartile range equals the value

 of the 75th percentile minus the

 value of the 25th percentile.

1.5 to 3 times the

 interquartile range from

 the 75-percentile value

1.5 to 3 times the

 interquartile range from

 the 25th percentile

(NUMBER OF SAMPLES) 1994 concentrations

Figure 19. Distribution of 1974-94 and 1994 dissolved-oxygen concentrations measured in the Columbia River at

Warrendale, lower Columbia River Basin, Oregon. (To avoid statistical bias that may be associated with constituen

analyzed more than once at a site, only one concentration per day was statistically summarized; see State of Oreg

for standards.)
47

O

(12)

M

(16)

EXPLANATION

Less than 1.5 times the

 interquartile range from

 the 75th percentile

75th percentile

Median

25th percentile

Less than 1.5 times the

 interquartile range from

 the 25th percentile

Interquartile range equals the value

 of the 75th percentile minus the

 value of the 25th percentile.

1.5 to 3 times the

 interquartile range from

 the 75th percentile

1.5 to 3 times the

 interquartile range from

 the 25th percentile

1994 concentrations

Data point—less than 3 samples

70

90

110

130

6

8

10

12

14

16

18

80

100

120

DISSOLVED OXYGEN, IN MILLIGRAMS PER LITER DISSOLVED OXYGEN, IN PERCENT SATURATION

0

2

4

6

8

10

12

14

DISSOLVED OXYGEN, IN MILLIGRAMS PER LITER

Oregon State Standard

J F

(2) (0)

M

(1)

A

(1)

M

(1)

J

(8)

J

(21)

A

(22)

O

(11)

N

(3)

D

(2)

S

(21)

YEARS 1949-58 (NUMBER OF SAMPLES)

J

(16)

F

(11)

A

(12)

M

(21)

J

(10)

J

(22)

A

(12)

S

(10)

N

(14)

D

(11)

YEARS 1972-94 (NUMBER OF SAMPLES)

O

(12)

M

(16)

J

(16)

F

(11)

A

(12)

M

(21)

J

(10)

J

(22)

A

(12)

S

(10)

N

(14)

D

(11)

YEARS 1972-94 (NUMBER OF SAMPLES)

Figure 20. Distribution of (A) 1949–58, (B) 1972–94, and 1994 dissolved-oxygen concentrations measured in the W

River at Portland, lower Columbia River Basin, Oregon. (To avoid statistical bias that may be associated with constit

analyzed more than once at a site, only one concentration per day was statistically summarized; see State of Orego

standards.)

A B

C
48

Figure 21. Distribution of 1960–74 and 1994 dissolvedoxygen concentrations measured in the Kalama River

above Spencer Creek near Kalama, lower Columbia River

Basin, Washington. (To avoid statistical bias that may be

associated with constituents analyzed more than once at a

site, only one concentration per day was statistically

summarized; see State of Oregon [1994] for standards.)

75

85

95

105

115

7

8

9

10

11

12

13

14

15

JAN

FEB

MAR

APR

MAY

JUNE

JULY

AUG

SEPT

OCT

NOV

DEC

YEARS 1960-70 AND 1994

DISSOLVED OXYGEN, IN MILLIGRAMS PER LITER DISSOLVED OXYGEN, IN PERCENT SATURATION

(8) (3)

(3)

(10)

(3)

(3)

(13)

(4)

(4)

(9)

(3) (3)

(8) (3)

(3)

(10)

(4)

(3)

(13)

(4)

(5) (9)

(4)

(3)

EXPLANATION

Less than 1.5 times the

 interquartile range from

 the 75th percentile

75th percentile

Median

25th percentile

Less than 1.5 times the

 interquartile range from

 the 25th percentile

Interquartile range equals the value

 of the 75th percentile minus the

 value of the 25th percentile.

1.5 to 3 times the

 interquartile range from

 the 25th percentile

1994 concentrations

(8) Number of samples

Washington State Standard

during the summer for navigation (Sherman

and the upgrading of wastewater discharges 

Willamette River Basin to secondary treatme

levels by 1972 (Rickert and others, 1976). T

major reason for the seasonal variability app

figures 20b and 20c can be attributed to temp

effects. Figure 20b can be viewed as an inve

figure 16, which shows the monthly variabil

temperature. Figure 20c shows that except fo

months of July through September, the disso

oxygen concentrations were generally within 

percent of saturation. During the low-flow su

period, the dissolved-oxygen concentrations 

low probably because point and nonpoint so

were still placing a biochemical demand on t

and biological respiration is consuming oxy

maximum rate during this period of maximu

temperatures. Most of the dissolved-oxygen

concentrations during the months of Decemb

January, February, April, and May were abo

100-percent saturation, likely as a result of a

caused by water spilling over Willamette Fa

(RM 26.6).

Dissolved-oxygen concentrations in the

Kalama River (fig. 21) are typical of a natur

stream, with water temperature being the do

factor on seasonal variability. As an example

few of the percent-saturation data in figure 2

outside the range of plus or minus 10 percen

saturation. Comparison of 1994 data to histo

data suggests that dissolved-oxygen concent

in 1994 were similar to those measured in 19

The pH of a water sample is a measure 

hydrogen-ion activity. Water is neutral at a p

and the pH can range from a minimum of 0 

acidic) to a maximum of 14 (highly alkaline

pH of a stream can change because of an inf

acidic or alkaline wastes or because of

photosynthesis and respiration (due to the da

cycles of release and uptake of carbon dioxi

aquatic plants). The toxicity to aquatic organ

several chemical constituents is affected by 

both directly and indirectly. Toxicity to fresh

aquatic life can occur when the pH falls outs

range of 6.5 to 8.5. A pH range of 5 to 9 is

necessary for water to be suitable for domes

water supplies (U.S. Environmental Protecti

Agency, 1986a). The dissociation of weak ac

bases is influenced by pH, which in turn, ind

affects aquatic life. For example, as pH incr
49

the ammonium ion is dissociated to the toxic unionized ammonia form.

In 1994, three measurements in the lower

Columbia River exceeded pH of 8.5 during April

and May (fig. 22a, and table 48 at back of report).

There were, however, no pH measurements near the

lower limit of 6.5. The higher pH values were not

associated with changes in alkalinity or specific

conductance. The higher pH measurements in April

and May in the Columbia River at RM 102 downstream from Hayden Island are associated with

increased chlorophyll a concentrations (an indirect

measure of algal productivity) in the water column

(fig. 22b). The associated seasonal increase of pH

and chlorophyll a suggests that phytoplankton may

have been an important factor relative to pH levels

in the lower Columbia River during April and May

of 1994.

Total Dissolved Gas

Water is spilled at Columbia River dams when

flows exceed the dams’ capacity to store water or

generate hydropower and to aid downstream

migration of anadromous juvenile fish. Because of

the Columbia River depths and the configuration of

J F M A M J J A S O N D

1994

0

30

5

10

15

20

25

7.8

9.0

8.0

8.2

8.4

8.6

8.8

9.0

PH, IN STANDARD UNITS

EXPLANATION

pH

CHLOROPHYLL-A

J F M A M J J A S O N D

1994

6.5

9.0

7.0

7.5

8.0

8.5

PH, IN STANDARD UNITS

EXPLANATION

MAIN- STEM SITES

TRIBUTARY SITES

A B

OREGON AND WASHINGTON STATE STANDARDS OREGON AND WASHINGTON STATE STA

Figure 22. (A) pH in the main stem and tributaries of the lower Columbia River Basin and (B) chlorophyll-a concentra

relation to pH in the Columbia River at river mile 102, downstream from Hayden Island, Oregon and Washington, 199

the dams spilling water into the next downst

pool, the spills usually cause atmospheric ga

go into solution, resulting in supersaturation 

in the river. When aquatic organisms are exp

these supersaturated concentrations, they ca

develop Gas-Bubble Trauma (National Mari

Fisheries Service, 1994). Some of the associ

difficulties for outmigrating juvenile salmon

identified in table 15.

Oregon and Washington both have Stat

standards of 110 percent of saturation for to

dissolved gas (TDG). TDG is equal to the su

partial pressures of nitrogen gas, oxygen gas

gas, and water vapor. State and Federal fishe

agencies requested the States of Washington 

Oregon to allow a variance to the TDG stand

during the spring and summer of 1994 that w

allow up to a 120 percent of saturation on a 

average. The request was made to permit the 

of water over spillways, thereby allowing m

salmon smolt to avoid hydropower turbines. 

request was granted by both states.

The U.S. Army Corps of Engineers h

monitoring total dissolved gas in the Columb

since 1984. A complete record of the TDGmonitoring program for 1994 can be found i
50

report by the U.S. Army Corps of Engineers (1994).

In 1994, they operated continuous TDG monitors in

the Columbia River at Warrendale (RM 140.5),

Skamania (RM 140.6), Camas (RM 122), Kalama

(RM 77), and Wauna Mill (RM 42). The TDG data

from these sites included values between 100 and

120 percent of saturation during most of the spring

and summer of 1994 decreasing in a downstream

direction from Bonneville Dam to Wauna Mill.

Figure 23 shows TDG concentrations at Warrendale

during April through September of 1994 and 1984–

93. The historic high values from April 15 through

July 15 were generally caused by spills released at

upstream dams because the Columbia River

streamflow exceeded the capacity of the

hydropower turbines. The higher-than-average

values in 1994 that occurred from July 15 through

August 20 were the result of requests for the U.S.

Army Corps of Engineers to spill water at the dams

during 12 hours each night to aid the outmigration

of anadromous fish.

The few concentrations of TDG measured by

the USGS were similar to the U.S. Army Corps of

Engineers data. Generally, the TDG and the

dissolved-oxygen concentrations (expressed as

percent of saturation) were similar in magni

This is to be expected because oxygen make

relatively constant proportion of atmospheric 

which were the major source of dissolved ga

lower Columbia River. (Photosynthesis and

respiration by aquatic organisms were minim

Suspended Sediment

 Suspended-sediment movement in stre

an important factor in the transport and fate 

chemicals in the environment. Many contam

including nutrients, trace elements, organic

compounds, and fecal-indicator bacteria are

associated with suspended sediment. Sedime

be transported in the water column or may b

deposited on the streambed for a period of ti

During the process of transport and depositi

suspended particles often sort themselves su

coarse sand will dominate in one area and fi

and clay particles in another area. Salinity ca

finest organic particles to coagulate and sett

(Thurman, 1985), resulting in areas near the

Columbia River mouth that are dominated b

fine sediment. Suspended-sediment concentr

Table 15. Signs of gas-bubble trauma in salmonids

[Adapted from National Marine Fisheries Service, 1994; %, percent]

Signs and effects Total dissolved gas threshold

(sea level) Age/class

Cardiovascular bubbles acutely lethal at 115-118 % Juveniles and adults

Subdermal emphysema including lining of

mouth

about 110 % Juveniles and adults

Bubbles in lateral line about 110 % Juveniles and adults

Rupture of swim bladder in small fish about 110 % Swim-up fry and juveniles

Over inflation of swim bladder in small fish about 103 % Swim-up fry and juveniles

Exophthalmia and ocular lesions unknown, 102 % for ocular lesions Juveniles and adults

Bubbles in intestinal tract 102 to 110 % Juveniles and adults, larval (physo

Loss of swimming ability about 106 % Juveniles and adults

Reduced growth 102 to 105 % (Chinook, lake trout) Juveniles

Immunosuppression (if present) greater than 108 % Juveniles and adults

Reduced ability to adapt to saltwater variable Juveniles
51

MONTH

96

128

100104108112116120124

TOTAL DISSOLVED GAS, IN PERCENT SATURATION

APRIL MAY JUNE JULY AUGUST 

MEAN A AVERA1994 DA

Figure 23. Total dissolved-gas concentrations in the Columbia River at Warrendale, lower Columbia River Basin, Oregon, 1984–Passage Center, Portland, Oregon, unpub. data, 1995.)
52

and associated contaminants can potentially affect

water used for domestic-water supplies, aquatic-life

propagation, and recreation. High suspendedsediment concentrations often are associated with

intense storms that increase streamflows, erosion,

and resuspension of bed sediment.

 Suspended-sediment concentrations analyzed

by State agencies (ODEQ and WDOE) are

gravimetric determinations of total suspended solids

remaining after drying the sample at 105°C

(STORET parameter code 00530; U.S. Environmental Protection Agency, 1979), and the USGS

analyses are gravimetric determinations of

suspended-sediment concentrations remaining after

drying the sample at 105°C (STORET parameter

code 80154; Guy, 1969). The ODEQ samples were

generally grab samples from one point in the stream

cross section, while the WDOE and USGS samples

were depth- and width-integrated samples collected

isokinetically relative to stream velocities. The

nonfilterable-residue method of determination (total

suspended solids) used by the State agencies

requires that an aliquot of sample be withdrawn

from a well-mixed sample bottle for analysis,

whereas the suspended-sediment method of

determination requires analysis of the entire

contents of sediment and water in a sample

container. As a result of differences in sampling and

analytical methods among agencies, and on the

basis of limited quality-assurance data (see QualityAssurance section of this report), data generated

from the two methods may not be comparable;

consequently, USGS and State agency data are

summarized separately (table 16).

Data from the four sites on the main stem

Columbia River indicates that suspended sediment

increases in a downstream direction (table 16). The

median concentration of suspended sediment in the

main stem ranged from 5 mg/L at Warrendale to

9 mg/L at Beaver Army Terminal. Maximum

suspended-sediment concentrations generally

coincided with peak streamflow for the Willamette

River at Portland and the Columbia River at

Warrendale (fig. 24). The Cowlitz and Willamette

Rivers had the largest median suspended sediment

concentrations (both were 21 mg/L, from USGS

data) of the tributaries to the Columbia River. The

Willamette and the Cowlitz Rivers had median

suspended-sediment concentrations approximately

5 to 10 times those of the Sandy, Lewis, and Kalama

Rivers. Results of the seasonal Kendall trend 

suspended-sediment concentration, both non

adjusted and flow adjusted, indicated no sign

< 0.05) trends at the Columbia River at Warr

the Willamette River at Portland (table 49, a

report).

Sites with adequate historical data to es

monthly and annual mean daily loads for su

sediment were the Columbia River at Warren

Columbia River at Beaver Army Terminal, a

Willamette River at Portland (tables 17 and 

the Willamette and Warrendale sites had eno

to estimate loads for a period of about 20 ye

(1974–94). Three water years from that peri

chosen (1977, 1975, 1974) to represent low-, 

and high-flow years, respectively. These wat

had flows similar to low-, median-, and high

water years shown for the period 1928–84 (s

fig. 6). The estimated annual loads of suspen

sediment for the current year (1994) are sim

estimated loads for 1977, a low-flow year (ta

Load estimates for the lower Columbia 

indicate seasonal variation in suspended sed

loads. During the period January through Ap

1994, the suspended-sediment loads in the W

River plus the loads at Warrendale were grea

the loads at Beaver Army Terminal (table 17

deficit of suspended sediment at Beaver Arm

Terminal may indicate deposition in the reac

this period. In contrast, from May to Decem

1994, the Columbia River had downstream “n

in suspended sediment loads from Warrenda

Beaver Army Terminal, which cannot be acc

for by only inputs from the Willamette Rive

example, in June, estimates of mean daily su

sediment load indicate that the Columbia Riv

2,300 tons per day between Warrendale and 

Army Terminal, while the Willamette River 

only 380 tons per day. The unaccounted-for 

be coming from the Cowlitz River and (or)

resuspension in the main stem. Unfortunatel

quality data were insufficient to calculate lo

suspended sediment on the Cowlitz River us

ESTIMATOR program. However, instantane

suspended-sediment loads for the Cowlitz R

that the Cowlitz River can produce loads of 

magnitude to those of the Willamette River 

812 tons/day). Therefore, the Cowlitz River 

account for a portion of the additional suspe

sediment load at Beaver Army Terminal. Fu
53

Table 16. Distribution of suspended-sediment and suspended-solids concentrations, lower Columbia River Basin, O[To avoid statistical bias that may be associated with constituents analyzed more than once at a site, only one concentration per month was statifor full site names; concentrations are reported in milligrams per liter; -- indicates fewer than 5 samples collected, therefore percentile not calcu

Site name Agency Number of samples Minimum value

Value at indicated

percentile 

25 50 75

Columbia River at Warrendale USGS 11 3 4 5 7 Columbia River at Hayden Island USGS 12 1 5 7 8 Columbia River near Columbia City USGS 12 5 5 9 15 Columbia River at Beaver Army Terminal USGS 11 5 8 9 16 Sandy River USGS 4 2 -- 3 -- Sandy River ODEQ 11 <1 2 4 6 Willamette River at Portland USGS 12 5 10 21 70 Willamette River at Portland ODEQ 11 2 4 5 6 Lewis River USGS 4 1 -- 2 -- Lewis River WDOE 10 1 2 4 6 Multnomah Channel USGS 11 7 9 11 17 Kalama River USGS 4 2 -- 4 -- Kalama River WDOE 10 1 3 4 8 Cowlitz River USGS 4 7 -- 21 -- Cowlitz River WDOE 10 2 6 7 28 
54

0

120

20

40

60

80

100

DAILY MEAN STREAMFLOW

SUSPENDED-SEDIMENT CONCENTRATION

WILLAMETTE RIVER AT PORTLAND

J F M A M J J A S O N D

1994

60

240

80

100

120

140

160

180

200

220

COLUMBIA RIVER AT WARRENDALE

DAILY MEAN STREAMFLOW, IN THOUSANDS OF CUBIC FEET PER SECOND

Figure 24. Relation between daily mean streamflow and suspended-sediment concentrations in the Willamette Riv

Portland and Columbia River at Warrendale, lower Columbia River Basin, Oregon, 1994.
55

higher flows in the Columbia River during May,

June, and July (fig. 8) may provide the energy

necessary to resuspend streambed sediment and

supply the additional load at Beaver Army

Terminal. Resuspension probably is greatest from

May through July and in December.

Nutrients

Historical data show that nutrient

concentrations are relatively low in the lower

Columbia River Basin. Nutrient concentrations

measured in 1994 were compared with historical

data (1964–93) from the lower Columbia River

Basin and data from 300 sites on rivers across the

United States (table 19). The 1994 median

concentration of phosphorus in unfiltered water is

much smaller in the lower Columbia River Basin

(0.03 mg/L) than the median for rivers across the

United States (0.17 mg/L). Nitrite-plus-nitrate

concentrations in filtered water have a similar

pattern, with a 1994-median concentration of 0.17

Table 17. Calculated monthly and annual mean daily loads for suspended sediment at selected sites, lower Colu

Basin, Oregon, 1994

[See table 7 for full site names; loads are reported in tons per day; -, minus; all mean daily loads were calculated using ESTIMATOR (Coh

1992)]

Month Warrendale Willamette Beaver Net gain

(Beaver - Warrendale)

Unaccounted-for loa

(Net gain - Willamett

January 3,900 2,800 5,000 1,100 -1,700

February 5,900 1,800 6,100 200 -1,600

March 5,900 1,600 6,500 600 -1,000

April 7,500 1,100 7,700 200 -900

May 11,000 330 12,000 1,000 670

June 8,700 380 11,000 2,300 1,900

July 4,900 200 6,700 1,800 1,600

August 2,000 200 2,700 700 500

September 1,200 260 1,700 500 240

October 1,800 590 2,700 900 310

November 2,400 3,500 6,700 4,300 800

December 3,600 6,900 13,000 9,400 2,500

Annual 4,900 1,600 6,800 1,900 300

mg/L in the lower Columbia River Basin com

to 0.71 mg/L for rivers across the United Sta

historical concentrations of nutrients in the l

Columbia River Basin were generally twice 

as the current concentrations. Differences be

the historical and current data likely are due 

predominance of data from the Willamette R

Basin in the historical database, rather than 

quality trend.

The Willamette River is affected by ma

municipal and agricultural sources, whereas 

the rest of the lower Columbia River Basin i

forest lands (fig. 9). As a result, historical

concentrations of nutrients are higher in the

Willamette River Basin when compared with 

in other areas of the lower Columbia River B

This pattern is apparent when the 90th-perce

concentrations for phosphorus in unfiltered w

and nitrite plus nitrate and ammonia in filtere

are compared by geographical areas (fig. 25
56

Table 18. Calculated monthly and annual mean daily suspended-sediment loads for the current water year and low, median, streamflow water years in the Columbia River at Warrendale and Willamette River at Portland, lower Columbia River Basin, O[See table 7 for full site name; loads are reported in tons per day; all mean daily loads were calculated using ESTIMATOR (Cohn and others, 1992); see thConditions” section for a description of flow-year designations]

Month

1977

Low streamflow year

1975

Median streamflow year

1974

High streamflow year

Warrendale Willamette Warrendale Willamette Warrendale Willamette Warren

October 3,500 540 3,000 590 2,200 510 2,00November 3,400 520 3,400 1,100 3,000 13,000 2,40December 4,100 200 4,200 5,700 6,300 16,000 2,90January 5,700 170 6,900 8,200 14,000 14,000 3,90February 5,000 150 9,200 3,900 14,000 5,500 5,90March 5,600 1,200 13,000 3,800 14,000 5,900 5,90April 4,500 530 13,000 1,200 22,000 4,200 7,50May 6,000 870 21,000 1,600 26,000 1,400 11,00June 4,700 440 19,000 660 33,000 1,600 8,70July 2,300 180 8,300 330 15,000 390 4,90August 2,100 220 3,500 290 5,100 200 2,00September 2,000 440 2,400 540 3,200 290 1,20

Annual 4,100 460 8,900 2,300 13,000 5,300 4,90
57

Table 19. Comparison of nutrient concentrations in water in the lower Columbia River Basin to surface waters of the United States[The term “filtered water” is an operational definition referring to the chemical analysis of that portion of a water-suspended sediment sample that pmicrometer filter; conversely, the term “unfiltered water” refers to the chemical analysis of a water sample that has not been filtered or centrifuged, nor matrix; to avoid statistical bias that may be associated with constituents analyzed more than once at a site, only one value per month per agency was ammonia plus organic nitrogen in filtered water, nitrite in filtered water, and phosphorus in filtered water are not included in this table due to lack oare reported in milligrams per liter as nitrogen or phosphorus; NASQAN, National Stream Accounting Network based on data from 300 sites across than; USGS, U.S. Geological Survey; ODEQ, Oregon Department of Environmental Quality; data for orthophosphate in filtered water from Washingtsummarized because all data were below the method reporting limit of 0.01 milligrams per liter]

Constituent name

NASQAN1974-81a

aRichard Alexander, U.S. Geological Survey, written communication, 1994.

Lower Columbia River Basin (1964-93)b

bU.S. Environmental Protection Agency’s STOrage and RETrieval system (STORET), U.S. Geological Survey’s National Water Information System (NWIS), 

Washington, unpub. data, 1994.

Lower Co

Value at indicated

percentile Number of

samples

Value at indicated percentile Number

of

samples

25 50 75 25 50 75 90 

Ammonia, filtered water -- -- -- 1,711 0.01 0.03 0.09 0.41 84 0.Ammonia plus organic nitrogen, unfiltered water -- -- -- 8,945 .2 .3 .6 1.1 94 <Nitrite plus nitrate, filtered water 0.43 0.71 1.1 1,122 .10 .37 1.2 2.5 84 .

Phosphorus, unfiltered water .11 .17 .27 10,927 .04 .07 .15 .30 114 .Orthophosphate, filtered water (USGS data only) -- -- -- 9,051 .010 .027 .060 .152 84 .

Orthophosphate, filtered water (ODEQ data only) -- -- -- 9,051 .010 .027 .060 .152 21 .
58

 1

Map

Symbol Subbasin or unit name Number ofsamples

A Lower Columbia (estuary) Unit 82

B Lower Columiba-Clatskanie 553

C Cowlitz River Subbasin 707

D Lewis River Subbasin 248

E Lower Columbia-Sandy, Washington 182

F Lower Willamette Unit 1202

G Lower Columbia-Sandy, Oregon 729

H Willamette River Subbasin 7166

C

G

A

B

D

F

E

H

Kalama River

Cowlitz

River

RIVER

River

Sandy

Lewis River

River

Willamette

COLUMBIA

R A N G E

R A N G E

C O A S T

C A S C A D E

Vancouver

Kalama

Longview

Bonneville

Dam

Eugene

Government

 Camp

Salem

Portland

Rainier

Prescott

Goble

Altoona

Wauna

Warrendale

Bradwood

Astoria

Cougar

10 20 30 MILES

0 10 20 30 KILOMETERS

0

124 123 122 47

46

45

44

EXPLANATION

Total Phosphorus

 Less than 0.1 milligrams per liter

 More than or equal to 0.1 and less than 0.2 milligrams per liter

 More than or equal to 0.2 and less than 0.3 milligrams per liter

 More than or equal to 0.3 milligrams per liter

Subbasin or u nit border

Basin border

A Subbasin or unit name

Map

Symbol Subbasin or unit name Numsam

A Lower Columbia (estuary) Unit 

B Lower Columiba-Clatskanie 

C Cowlitz River Subbasin insuffic

D Lewis River Subbasin insuffic

E Lower Columbia-Sandy, Washington 

F Lower Willamette Unit 

G Lower Columbia-Sandy, Oregon 

H Willamette River Subbasin 

C

G

A

B

D

F

E

H

Kalama River

Cowlitz

River

RIVER

River

Sandy

Lewis River

River

Willamette

COLUMBIA

R A N G E

C O A S T

Vancouver

Kalama

Longview

Bonne

Dam

Eugene

Government

 Camp

Salem

Portland

Rainier

Prescott

Goble

Altoona

Wauna

Warrend

Bradwood

Astoria

Cougar

10 20 30 MILES

0 10 20 30 KILOMETERS

0

124 123 122 47

46

45

44

EXPLANATION

Nitrite plus nitrate

 Insufficient data

 Less than 0.5 milligrams per liter

 More than or equal to 0.5 and less than 1.0 millig

 More than or equal to 2.0 milligrams per liter

Subbasin or u nit border

Basin border

A Subbasin or unit name
59

Map

Symbol Subbasin or unit name Number ofsamples

A Lower Columbia (estuary) Unit 8

B Lower Columiba-Clatskanie 56

C Cowlitz River Subbasin insufficient data

D Lewis River Subbasin insufficient data

E Lower Columbia-Sandy, Washington 13

F Lower Willamette Unit 190

G Lower Columbia-Sandy, Oregon 94

H Willamette River Subbasin 967

C

G

A

B

D

F

E

H

Kalama River

Cowlitz

River

RIVER

River

Sandy

Lewis River

River

Willamette

COLUMBIA

R A N G E

R A N G E

C O A S T

C A S C A D E

Vancouver

Kalama

Longview

Bonneville

Dam

Eugene

Government

 Camp

Salem

Portland

Rainier

Prescott

Goble

Altoona

Wauna

Warrendale

Bradwood

Astoria

Cougar

10 20 30 MILES

0 10 20 30 KILOMETERS

0

124 123 122 47

46

45

44

EXPLANATION

Ammonia

 Insufficient Data

 Less than 0.1 milligram per liter

 More than or equal to 0.1 and less than 0.2 milligram per liter

 More than or equal to 0.5 milligram per liter

Subbasin or u nit border

Basin border

A Subbasin or unit name

showing the 90th percentiles of all historica

sampled in each subbasin or unit, figure 25 i

which subbasins or units of the lower Colum

River Basin had comparatively low, medium

historical nutrient concentrations. The histor

were grouped into subbasins and units for st

purposes only; these maps do not imply that 

indicated nutrient concentration existed ever

in a given unit. The maps do show in a gene

the historical nutrient concentrations of diffe

areas of the lower Columbia River Basin, as

recorded by the sampling done. Detailed his

nutrient data are not presented, however, bec

sampling methods and quality of data are un

Current data for nutrient concentration

that the Willamette River is a significant sou

nutrients in the lower Columbia River Basin

1994, samples were collected and analyzed f

phosphorus and ammonia plus organic nitro

unfiltered water and ammonia, nitrite plus n

and orthophosphate in filtered water. The me

concentration for each of the five species wa

at the Willamette River at Portland sampling 

(table 20). When ranking the median concen

from highest to lowest, the same general ord

concentrations was followed at all sampling 

all of the constituents analyzed:

Willamette River > Multnomah Channe

Columbia River sites downstream of the Wil

River > Columbia River sites upstream of th

Willamette River > other tributaries.

Concentrations of ammonia and ammon

organic nitrogen were usually near the meth

reporting limit.

Seasonal variations in nutrient concent

were apparent in 1994. Phosphorus concentra

unfiltered water in the Willamette River at P

were highest from November to February, du

periods of winter-storm activity (fig. 26). In c

a large seasonal variation was not observed 

phosphorus in the Columbia River at Hayden 

(RM 102) and Columbia River near Columb

(RM 84). All three sites had variation, howe

concentrations of nitrite plus nitrate in filtere

The highest concentrations in the Willamette 

Figure 25. Spatial distribution of 90th-percentile val

phosphorus concentrations in unfiltered water and n

nitrate and ammonia in filtered water by subbasin or 

Columbia River Basin, Oregon and Washington, 19
60

.

Table 20. Distribution of nutrient concentrations in water, lower Columbia River Basin, Oregon and Washington, 1994

[The term “filtered water” is an operational definition referring to the chemical analysis of that portion of a water-suspended sediment sample that 

a nominal 0.45-micrometer filter; conversely, the term “unfiltered water” refers tot he chemical analysis of a water sample that has not been filtered 

nor in any way altered from the original matrix; to avoid statistical bias that may be associated with constituents analyzed more than once at a site

concentration per month per agency was statistically summarized; values are reported in milligrams per liter as nitrogen or phosphorus; see table 

names; USGS, U.S. Geological Survey; ODEQ, Oregon Department of Environmental Quality; WDOE, Washington Department of Ecology; <, les

than 5 samples collected, therefore percentile not calculated; for orthophosphate, different reporting limits were used by different agencies]

Site name Agenc

y

Number

of samples

Minimum

value

Value at indicated

percentile Maximum

value

25 50 75

Ammonia, filtered water

Columbia River at Warrendale USGS 11 <0.01 0.01 0.02 0.03 0.06

Columbia River at Hayden Island USGS 12 .01 .02 .03 .05 .09

Columbia River near Columbia City USGS 12 .01 .02 .03 .04 .07

Columbia River at Beaver Army Terminal USGS 11 .02 .02 .03 .04 .06

Willamette River at Portland USGS 12 .04 .05 .06 .09 .12

Multnomah Channel near mouth USGS 11 <.01 .02 .03 .07 .13

Sandy River near Troutdale USGS 4 <.01 -- .01 -- .02

Lewis River at Woodland USGS 4 .01 -- .01 -- .02

Kalama River near Kalama USGS 4 .01 -- .02 -- .03

Cowlitz River at Kelso USGS 3 <.01 -- <.01 -- .01

Ammonia plus organic nitrogen, unfiltered water

Columbia River at Warrendale USGS 11 <.2 <.2 <.2 <.2 .3

Columbia River at Hayden Island USGS 12 <.2 <.2 <.2 .2 .3

Columbia River near Columbia City USGS 12 <.2 <.2 <.2 .2 .5

Columbia River at Beaver Army Terminal USGS 11 <.2 <.2 <.2 .3 .5

Willamette River at Portland USGS 12 <.2 .2 .3 .5 .5

Willamette River at Portland ODEQ 11 <.2 .3 .4 .4 .7

Multnomah Channel near mouth USGS 11 <.2 <.2 .2 .3 .3

Sandy River near Troutdale USGS 4 <.2 -- <.2 -- <.2

Sandy River near Troutdale ODEQ 11 <.2 <.2 .2 .2 .4

Lewis River at Woodland USGS 4 <.2 -- <.2 -- <.2

Kalama River near Kalama USGS 4 <.2 -- <.2 -- <.2

Cowlitz River at Kelso USGS 3 <.2 -- <.2 -- <.2

Nitrite plus nitrate, filtered water

Columbia River at Warrendale USGS 11 <.05 <.05 .16 .22 .42

Columbia River at Hayden Island USGS 12 <.05 .05 .11 .32 .73

Columbia River near Columbia City USGS 12 <.05 .07 .18 .37 .56

Columbia River at Beaver Army Terminal USGS 11 <.05 .09 .17 .35 .47

Willamette River at Portland USGS 12 .23 .30 .70 .97 1.4

Multnomah Channel near mouth USGS 11 .05 .13 .24 .42 1.1

Sandy River near Troutdale USGS 4 <.05 -- .04 -- .07

Lewis River at Woodland USGS 4 <.05 -- <.05 -- .31

Kalama River near Kalama USGS 4 0.06 -- 0.07 -- 0.12

Cowlitz River at Kelso USGS 3 .06 -- .08 -- .15
61

Orthophosphate, filtered water

Columbia River at Warrendale USGS 11 .001 0.002 .010 0.013 .017

Columbia River at Hayden Island USGS 12 .002 .007 .012 .015 .042

Columbia River near Columbia City USGS 12 .001 .003 .013 .018 .030

Columbia River at Beaver Army Terminal USGS 11 .004 .005 .016 .020 .024

Willamette River at Portland USGS 12 .010 .031 .040 .060 .070

Willamette River at Portland ODEQ 11 .036 .041 .054 .065 .069

Multnomah Channel near mouth USGS 11 .003 .011 .029 .041 .049

Sandy River near Troutdale USGS 4 .002 -- .004 -- .007

Sandy River near Troutdale ODEQ 10 <.005 <.005 .006 .007 .010

Lewis River at Woodland USGS 4 <.001 -- .001 -- .002

Lewis River at Woodland WDOE 10 <.01 <.01 <.01 <.01 <.01

Kalama River near Kalama USGS 4 .006 -- .008 -- .008

Kalama River near Kalama WDOE 10 <.01 <.01 <.01 <.01 <.01

Cowlitz River at Kelso USGS 3 .001 -- .001 -- .002

Cowlitz River at Kelso WDOE 10 <.01 <.01 <.01 <.01 <.01

Phosphorus, unfiltered water

Columbia River at Warrendale USGS 11 <.01 .02 .02 .04 .04

Columbia River at Hayden Island USGS 12 .02 .03 .03 .04 .05

Columbia River near Columbia City USGS 12 .02 .03 .04 .04 .05

Columbia River at Beaver Army Terminal USGS 11 .02 .03 .04 .04 .06

Willamette River at Portland USGS 12 .05 .07 .09 .14 .24

Willamette River at Portland ODEQ 11 .06 .08 .09 .11 .16

Multnomah Channel near mouth USGS 11 .02 .03 .06 .08 .09

Sandy River near Troutdale USGS 4 <.01 -- <.01 -- .02

Sandy River near Troutdale ODEQ 10 <.01 .01 .02 .02 .03

Lewis River at Woodland USGS 4 <.01 -- <.01 -- .02

Lewis River at Woodland WDOE 10 <.01 <.01 .01 .02 .02

Kalama River near Kalama USGS 4 <.01 -- .01 -- .02

Kalama River near Kalama WDOE 10 <.01 .01 .02 .02 .03

Cowlitz River at Kelso USGS 3 <.01 -- .01 -- .02

Cowlitz River at Kelso WDOE 10 <.01 <.01 .02 .04 .08

Table 20. Distribution of nutrient concentrations in water, lower Columbia River Basin, Oregon and Washington, 1994—

[The term “filtered water” is an operational definition referring to the chemical analysis of that portion of a water-suspended sediment sample that 

a nominal 0.45-micrometer filter; conversely, the term “unfiltered water” refers tot he chemical analysis of a water sample that has not been filtered 

nor in any way altered from the original matrix; to avoid statistical bias that may be associated with constituents analyzed more than once at a site

concentration per month per agency was statistically summarized; values are reported in milligrams per liter as nitrogen or phosphorus; see table 

names; USGS, U.S. Geological Survey; ODEQ, Oregon Department of Environmental Quality; WDOE, Washington Department of Ecology; <, les

than 5 samples collected, therefore percentile not calculated; for orthophosphate, different reporting limits were used by different agencies]

Site name Agenc

y

Number

of samples

Minimum

value

Value at indicated

percentile Maximum

value

25 50 75
62

and Columbia River near Columbia City occurred

during the period of November to March, whereas

the highest concentrations in the Columbia River at

Hayden Island occurred in March and April. This

difference in peaks on the Columbia River was

probably due to the influence of the Willamette

River. During these periods of colder temperatures

and less light, nitrogen uptake by algae is

decreased, therefore, the nitrogen concentration in

the Columbia River is increased. As expected, the

concentrations then decrease during the months of

April through October when algal activity is

increased.

The historical data were analyzed for trends in

phosphorus, ammonia, nitrite plus nitrate, and

0

0.28

0.04

0.08

0.12

0.16

0.20

0.24

PHOSPHORUS, IN MILLIGRAMS PER LITER

0

1.6

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

NITRITE PLUS NITRATE, IN MILLIGRAMS PER LITER

J F M A M J J A S O N D

1994

COLUMBIA RIVER AT

HAYDEN ISLAND

COLUMBIA RIVER NEAR

COLUMBIA CITY

WILLAMETTE RIVER

AT PORTLAND

Figure 26. Concentrations of phosphorus in unfiltered

water and nitrite plus nitrate in filtered water in the

Columbia River at Hayden Island, Willamette River at

Portland, and Columbia River near Columbia City, lower

Columbia River Basin, Oregon and Washington, 1994.

orthophosphate. Seasonal Kendall trend tests 

a significant (ρ < 0.05) downward trend for

phosphorus (unfiltered) in the Columbia Riv

Warrendale for the period 1973–94 (table 50

of report). Phosphorus concentrations decrea

2.8 percent (nonflow adjusted) or 2.3 percen

adjusted) per year. This was the largest trend 

in the lower Columbia River Basin. This tren

be a consequence of more conservative agric

practices in the area upstream from Warrend

similar downward trend in phosphorus

concentrations was observed in the Yakima R

Basin, the most intensively irrigated basin in 

United States, which drains to the Columbia 

upstream from Warrendale (Rinella and othe

1992, p. 110). Because phosphorus is comm

associated with sediment particles (Hem, 19

downward trend also may have been influen

the downward trend in suspended-sediment

concentration. No significant trends for phos

were found in the Willamette River at Portla

only other site with adequate data for trend t

There were not adequate data to test for tren

ammonia, nitrite-plus-nitrate, and orthophos

concentrations.

Adequate historical data were available 

Columbia River at Warrendale and the Willa

River at Portland to calculate monthly and a

mean daily loads for phosphorus in unfiltere

and ammonia and nitrite plus nitrate in filtere

for a period of about 20 years (1974–94). Se

“Data-Analysis Methods” section for a discu

the use of the ESTIMATOR program. The 1

1975, and 1977 water years represent condit

high-, median-, and low-streamflow, respect

and their estimated loads are shown in table 

When the nutrient loads for the 1994 water y

compared with these historic loads, they are 

in magnitude to the low-flow water year of 1

(table 21). This is consistent with the fact th

was generally a year of lower precipitation a

streamflow.

Load is a function of both concentratio

streamflow. This relation explains how the a

mean daily loads for ammonia, nitrite plus n

and phosphorus in 1994 at Warrendale could 

larger by about twofold than those loads in t

Willamette River (table 21), even though co

trations were higher in the Willamette River 

Warrendale (table 20).
63

Table 21. Calculated monthly and annual mean daily nutrient loads for the current water year and low, median, and high stre

in the Columbia River at Warrendale and Willamette River at Portland, lower Columbia River Basin, Oregon

[See table 7 for full site name; loads are reported in tons per day; all mean-daily loads were calculated using ESTIMATOR (Cohn and others, 1992); see tsection for a description of flow-year designations]

Month

1977

Low streamflow year

1975

Median streamflow year

1974

High streamflow year

Warrendale Willamette Warrendale Willamette Warrendale Willamette Warren

Ammonia, filtered water

October 24 3 21 4 14 3 12 November 18 4 18 5 16 15 12 December 15 3 16 12 25 20 10 January 14 3 18 16 42 19 8 February 8 3 17 12 28 14 10 March 7 7 21 11 23 13 7 April 5 4 20 6 40 10 10 May 9 4 46 6 58 6 21 June 10 3 62 3 130 5 23 July 7 2 35 2 68 3 18 August 10 2 19 2 29 2 9 September 12 3 15 3 22 2 6 

Annual 12 3 26 7 41 9 12 

Nitrite plus nitrate, filtered water

October 60 14 54 15 41 14 37 November 87 18 87 30 79 150 66 December 130 13 130 120 180 240 95 January 170 16 200 200 360 280 130 February 130 15 210 140 300 170 150 March 100 59 210 120 210 170 100 
64

Nitrite plus nitrate, filtered water—Continued

April 53 28 130 47 200 110 81 May 46 29 130 44 160 40 79 June 29 13 96 18 150 31 49 July 15 6 44 9 70 10 29 August 17 6 27 7 36 6 16 September 25 10 28 11 36 8 16 

Annual 72 19 110 63 150 100 70 

Phosphorus, unfiltered water

October 17 4 15 4 10 4 9 November 16 4 16 6 14 23 12 December 18 2 19 15 29 28 12 January 21 2 26 19 57 25 14 February 15 2 28 12 44 15 17 March 13 6 35 11 37 15 14 April 9 4 29 6 53 11 16 May 13 4 49 6 62 6 25 June 11 3 51 4 94 6 21 July 6 2 24 2 45 3 14 August 7 2 12 2 18 2 6 September 8 3 10 4 14 2 5 

Annual 13 3 26 8 40 12 14 

Table 21. Calculated monthly and annual mean daily nutrient loads for the current water year and low, median, and high stre

in the Columbia River at Warrendale and Willamette River at Portland, lower Columbia River Basin, Oregon—Continued

[See table 7 for full site name; loads are reported in tons per day; all mean-daily loads were calculated using ESTIMATOR (Cohn and others, 1992); see tsection for a description of flow-year designations]

Month

1977

Low streamflow year

1975

Median streamflow year

1974

High streamflow year

Warrendale Willamette Warrendale Willamette Warrendale Willamette Warren
65

Nutrient loads also had seasonal patterns.

Phosphorus and ammonia had the same pattern of

higher loads during periods of higher streamflow.

This period corresponds to May through July for the

Columbia River at Warrendale and November

through March for the Willamette River (fig. 8).

Since phosphorus is commonly associated with

sediment particles (Hem, 1989) and higher

suspended-sediment concentrations and loads

correspond to seasonally higher streamflows (table

18), it is expected that phosphorus loads would be

larger when flows are higher. Because of the

relation between load and streamflow, ammonia

loads also would be expected to increase during

periods of higher runoff. In contrast to ammonia and

phosphorus, nitrite-plus-nitrate loads are influenced

more by season than by streamflow. Both the

Warrendale and the Willamette sites had their

highest loads during the winter months of December

through March. During these periods of colder

temperatures and less light, nitrogen uptake by

algae is decreased, and, therefore, the nitrogen

concentration in the river is increased.

Seasonal patterns for ammonia and phosphorus

loads at Warrendale differed among low, median,

and high streamflow years (table 21). In 1977, for

example, the typically higher streamflows in the

Columbia River from May through July were absent

(fig. 5); consequently, June phosphorus loads in

1977 were nearly nine times smaller than in June

1974—a high streamflow year. Similar patterns and

magnitude differences existed for ammonia loads

among streamflow years.

Loads were also calculated (using the

ESTIMATOR program) for the same three nutrient

constituents at the Columbia River at Beaver Army

Terminal for 1994, using data from 1990–94 to

calculate the regression equation. Table 22 shows

these load estimates for the calendar year 1994 at all

three sites for comparison. Because the Willamette

River is the major source of nutrients to the

Columbia River main stem between the Warrendale

and Beaver sites, from a simple mass balance

standpoint, loads at the Beaver site would be

expected to be approximately equal to the sum of

the loads at the Warrendale and Willamette sites

during the entire year. However, that was the case

only for phosphorus (fig. 27); load sums for

ammonia and nitrite plus nitrate differed from the

load at Beaver during much of 1994. The

explanation for the differences is tied to alga

cycles.

The loads for ammonia generally fit the

additive model from November through Apr

May through October, however, the load at B

was much lower than expected from the sum

example, in June, the load at Beaver (12 ton

was less than half of the sum of the loads at

Warrendale and Willamette (26 tons/day). T

period corresponds to the growth period in t

life cycle when nitrogen uptake is at its max

Consequently, some of the ammonia, the pre

nitrogen species for algae, probably is consu

the algae before it reaches Beaver Army Ter

The relation between the algae and ammonia 

seen in the ratio of the chlorophyll a concen

in milligrams per liter (an indirect measure o

productivity) to the ammonia concentration 

millgrams per liter. The ratio increased tenfo

February 17 (54) to June 10 (560), supportin

concept that increased algal activity in the s

results in decreased ammonia concentrations

The algae have a similar effect on the n

plus-nitrate loads from June through Septem

all three sites, but, in general, the additive m

holds. From October to May, however, the lo

Beaver is much higher than predicted by the 

the Warrendale and Willamette loads. This p

suggests that the input from the Willamette 

does not fully account for the increase, and 

from the other tributaries and point and nonp

sources have a significant effect during this 

period. Possible sources of nitrite plus nitrat

include the 39 domestic facilities (most of w

sewage-treatment plants) that ultimately disc

into the Columbia River (fig. 10).

For all three constituents, the load at Be

December was much higher than for the rest 

year. This is especially apparent for the nitri

plus-nitrate load, which had a mean daily va

730 tons/day for December and a second-hig

value of only 370 tons/day for February. The

elevated December loads at Beaver were due 

increased streamflow at Beaver, not increase

concentrations. For example, the nitrite-plus

concentration rose from 0.35 mg/L on Nove

at Beaver to only 0.37 mg/L on December 8

streamflow nearly doubled from 150,000 ft3

October 27 to 296,000 ft3/s on December 8. 

contrast, the streamflow at Warrendale was k
66

Table 22. Calculated monthly and annual mean daily loads for ammonia and nitrite plus nitrate in filtered water and phosphorus in unfilower Columbia River Basin, Oregon, 1994[The term “filtered water” is an operational definition referring to the chemical analysis of that portion of a water-suspended sediment sample that passes through a nomthe term “unfiltered water” refers to the chemical analysis of a water sample that has not been filtered or centrifuged, nor in any way altered from the original matrix; table 7 for full site names; all mean daily loads calculated using ESTIMATOR (Cohn and others, 1992a)]

Month

Ammonia, filtered water Nitrite plus nitrate, filtered water Phosp

Warrendale Willamette Beaver Warrendale + Willamette Warrendale Willamette Beaver Warrendale + Willamette Warrendale Wil

January 8 10 17 18 130 91 380 221 14 February 10 7 17 17 150 70 370 220 17 March 7 8 14 15 100 71 240 171 14 April 10 6 13 16 81 46 140 127 16 May 21 3 15 24 79 15 110 94 25 June 23 3 12 26 49 12 59 61 21 July 18 2 8 20 29 6 30 35 14 August 9 2 5 11 16 6 16 22 6 September 6 2 4 8 16 7 18 23 5 October 10 3 8 13 34 14 58 48 8 November 12 9 19 21 66 64 250 130 11 December 13 14 35 27 120 140 730 260 16 

Annual 12 6 14 18 71 45 200 116 14 
67

0

800

200

400

600

MONTHLY MEAN-DAILY LOAD, IN TONS PER DAY

NITRITE PLUS NITRATE

0

50

10

20

30

40

COLUMBIA RIVER AT WARRENDALE

COLUMBIA RIVER AT BEAVER ARMY TERMINAL

SUM OF COLUMBIA RIVER AT WARRENDALE AND WILLAMETTE RIVER AT PORTLAND

WILLAMETTE RIVER AT PORTLAND

AMMONIA

J F M A M J J A S O N 

1994

0

50

10

20

30

40

PHOSPHORUS

Figure 27. Monthly mean daily loads of ammonia and nitrite plus nitrate in filtered water and phosphorus in unfiltere

Columbia River at Warrendale, Willamette River at Portland, and Columbia River at Beaver Army Terminal, lower Co

Basin, Oregon and Washington, 1994.
68

within the range of about 90,000 ft3/s to 140,000

ft3/s by the operation of Bonneville Dam (fig. 8).

The transport dynamics of these three nutrients

were studied by computing the instantaneous loads

over three reaches of the main stem. The loads were

calculated for both July and September of 1994. For

each reach, the measured load at the downstream

site (site-measured load) was compared with the

calculated load for the reach (reach-calculated

load), and the difference between the two was

computed (tables 23 and 24). This type of analysis

is called mass balance. The smaller the difference

between the site-measured load and the reachcalculated load, the better the mass balance is for

the reach. For comparison, mass-balance

calculations also were made for streamflow, a

conservative measure, and suspended sediment, a

measure related to phosphorus loads. A positive

difference between measured and calculated

nutrient loads (calculated load greater than

measured load) implies that unmeasured

contributions to the site-measured load exist (from

point sources, nonpoint sources, or resuspension

and transport of streambed sediment); whereas a

negative difference implies that unmeasured losses

exist in the reach (from biological processes or

suspended-sediment deposition). It should be noted

that samples used in making intersite-load

comparisons in this study were separated by days or

weeks. Consequently, variability in daily mean

streamflow and daily concentrations can contribute

to differences that were observed between sitemeasured and reach-calculated loads.

In general, the mass balance for ammonia and

nitrite-plus-nitrate loads was better in September

than in July (table 23). Streamflow in the Columbia

River was less variable during the September period

than in July, when the streamflow was still

decreasing (fig. 8). Another possible explanation for

differences in mass balance between July and

September is the effect of algal productivity. For

example, chlorophyll a concentrations at Beaver

decreased from 6.5 μg/L on July 28 to only 3.3 μg/L

on September 12. This decrease indicates that algal

productivity in July probably accounts for decreases

in ammonia and nitrate loads. This removal by the

algae may explain the losses in load reported at

Beaver of 4.6 tons/day of ammonia and 20 tons/day

of nitrite plus nitrate.

When examining the loads for phospho

unfiltered water, it is important also to exam

loads for suspended sediment (table 24). In J

difference between site-measured and reach

calculated loads for suspended sediment and

phosphorus can best be described by the effe

streamflow. For example, in the reach from H

Island (RM 102) to Columbia City (RM 84)

unaccounted-for gains in both phosphorus an

suspended-sediment loads may be explained 

increased streamflow and resuspension of su

sediment. In September, phosphorus loads,

suspended-sediment loads, and streamflow w

smaller than they were in July. In table 24, t

very good balance for both phosphorus and

suspended-sediment loads for the reach from

Hayden Island to Columbia City, indicating 

no net deposition or resuspension. From Col

City to Beaver (RM 53.8), however, there ar

unaccounted-for losses in both phosphorus a

suspended sediment, indicating that depositi

occurring. This situation was expected due t

large input of suspended-sediment from the 

River and the low streamflow in the Columb

main stem. The suspended-sediment load fro

Cowlitz River (270 tons/day) represents 22 p

of the load measured at Beaver (1,200 tons/d

Major Ions and Related Measures

Sources of major ions in water include 

and organic assemblages in rocks and soils t

contact surface and ground water and underg

natural weathering (solubilizing processes).

Additional sources include point discharges 

example, effluents from sewage-treatment pl

and nonpoint discharges (for example, agric

and urban runoff). Major cations include cal

(Ca), magnesium (Mg), sodium (Na), and po

(K); major anions include bicarbonate (HCO

sulfate (SO4), chloride (Cl), fluoride (F), and 

(NO3), and uncharged species such as silica

[Si(OH)4]. Collectively, the total concentrat

dissolved material in water (inorganic salts a

organic matter) is referred to as total dissolv

solids (TDS) or “filterable residue”.

Median concentrations of Ca, Mg, Na, 

SO4, and TDS (14, 4.0, 6.3, 1.1, 4.1, 9.6 and 

mg/L, respectively) in the lower Columbia R

Basin in 1994 (table 25) were similar to mea
69

Table 23. Mass balances for streamflow and ammonia and nitrite-plus-nitrate loads in filtered water, lower Columbia River Basin, Ore[Loads were determined from instantaneous measurements of ammonia and nitrite-plus-nitrate concentrations in filtered water and phosphorus concentrations in unfan operational definition referring to the chemical analysis of that portion of a water-suspended sediment sample that passes through a nominal 0.45-micrometer filterrefers to the chemical analysis of a water sample that has not been filtered or centrifuged, nor in any way altered from the original matrix; ft3/s, cubic feet per secon

(below method reporting limit); see table 7 for full site names; see page 73 for a discussion of the mass-balance approach]

Site name Sampling date Columbia river mile

Streamflow (ft3/s) Ammonia load (tons/day) Nit

Main Stem

Tributary

inflowing

Main stem

Tributary

Inflowing

Site

measured

Reach

calculated

Site measured -

Reach calculated

Site

measured

Reach

calculated

Site measured -

Reach calculated

Site

July 1994

Warrendale 07-27-1994 141 144,000 -- -- -- 12 -- -- -- 2Sandy River 07-07-1994 120.5 -- -- -- 725 -- -- -- 0.020 Hayden Island 07-25-1994 102 142,000 144,725 -2,725 -- 15 12 +3 -- 1Willamette River 07-25-1994 101.5 -- -- -- 9,000 -- -- -- 1.4 Lewis River 07-19-1994 87 -- -- -- 1,260 -- -- -- .068 Columbia City 07-26-1994 84 160,000 152,260 +7,740 -- 13 16 -3 -- 6Kalama River 07-13-1994 73.1 -- -- -- 260 -- -- -- .014 Cowlitz River 07-14-1994 68 -- -- -- 4,390 -- -- -- cd Beaver Army Terminal 07-28-1994 53.8 155,000 164,650 -9,650 -- 8.4 13 -4.6 -- 4

September 1994

Warrendale 09-15-1994 141 72,500 -- -- -- 3.9 -- -- -- cSandy River 09-19-1994 120.5 -- -- -- 299 -- -- -- .016 Hayden Island 09-13-1994 102 73,700 72,799 +901 -- 4.0 3.9 +.1 -- 1Willamette River 09-13-1994 101.5 -- -- -- 9,100 -- -- -- 2.2 Lewis River 09-07-1994 87 -- -- -- 1,250 -- -- -- .034 Columbia City 09-14-1994 84 97,200 84,050 +13,150 -- 5.2 6.2 -1 -- 1Kalama River 09-06-1994 73.1 -- -- -- 189 -- -- -- .0051 Cowlitz River 08-31-1994 68 -- -- -- 3,230 -- -- -- cd Beaver Army Terminal 09-12-1994 53.8 93,000 100,619 -7,619 -- 5.0 5.2 -.2 -- 2
70

Table 24. Mass balances for streamflow, phosphorus loads in unfiltered water, and suspended-sediment loads, lower Columbia River 

1994

[Loads were determined from instantaneous measurements of ammonia and nitrite-plus-nitrate concentrations in filtered water and phosphorus concentrations in unan operational definition referring to the chemical analysis of that portion of a water-suspended sediment sample that passes through a nominal 0.45-micrometer filterrefers to the chemical analysis of a water sample that has not been filtered or centrifuged, nor in any way altered from the original matrix; ft3/s, cubic feet per secon

(below method reporting limit); see table 7 for full site names; see page 73 for a discussion of the mass-balance approach]

Site name Sampling date Columbia river mile

Streamflow (ft3/s) Phosphorus load (tons/day) 

Main Stem

Tributary

inflowing

Main stem

Tributary

Inflowing

Site

measured

Reach

calculated

Site measured -

Reach calculated

Site

measured

Reach

calculated

Site measured -

Reach calculated

Site

July 1994

Warrendale 07-27-1994 141 144,000 -- -- -- 7.8 -- -- -- 2,3Sandy River 07-07-1994 120.5 -- -- -- 725 -- -- -- cd -- Hayden Island 07-25-1994 102 142,000 144,725 -2,725 -- 12 7.8 +4.2 -- 2,7Willamette River 07-25-1994 101.5 -- -- -- 9,000 -- -- -- 2.7 -- Lewis River 07-19-1994 87 -- -- -- 1,260 -- -- -- 0.068 -- Columbia City 07-26-1994 84 160,000 152,260 +7,740 -- 17 15 +2 -- 3,9Kalama River 07-13-1994 73.1 -- -- -- 260 -- -- -- .021 -- Cowlitz River 07-14-1994 68 -- -- -- 4,390 -- -- -- .12 -- Beaver Army Terminal 07-28-1994 53.8 155,000 164,650 -9,650 -- 25 17 +8 -- 3,3

September 1994

Warrendale 09-15-1994 141 72,500 -- -- -- 3.9 -- -- -- 7Sandy River 09-19-1994 120.5 -- -- -- 299 -- -- -- cd -- Hayden Island 09-13-1994 102 73,700 72,799 +901 -- 6.0 3.9 +2.1 -- 1,2Willamette River 09-13-1994 101.5 -- -- -- 9,100 -- -- -- 1.7 -- Lewis River 09-07-1994 87 -- -- -- 1,250 -- -- -- cd -- Columbia City 09-14-1994 84 97,200 84,050 +13,150 -- 7.9 7.7 +.2 -- 1,3Kalama River 09-06-1994 73.1 -- -- -- 189 -- -- -- .0051 -- Cowlitz River 08-31-1994 68 -- -- -- 3,230 -- -- -- cd -- Beaver Army Terminal 09-12-1994 53.8 93,000 100,619 -7,619 -- 5.0 7.9 -2.9 -- 1,2
71

Table 25. Distribution of major-ion concentrations in filtered and unfiltered water, lower Columbia River Basin, O

Washington, 1994

 [All measurements were performed on filtered-water samples, except specific conductance which was determined from an unfiltered-wa

term “filtered water” is an operational definition referring to the chemical analysis of that portion of a water-suspended sediment sample 

through a nominal 0.45-micrometer filter; conversely, the term “unfiltered water” refers to the chemical analysis of a water sample that has n

or centrifuged, nor in any way altered from the original matrix; to avoid statistical bias that may be associated with constituents analyzed 

at a site, only one element concentration per month was statistically summarized; values are reported in milligrams per liter, except wher

otherwise; see table 7 for full site names; -- indicates fewer than 6 samples collected, therefore the percentile was not calculated; <, less t

 Site name

Number

of

samples

Minimum

value

Value at indicated percentile Maxim

val

10 25 50 75 90

Alkalinity

 Warrendale 11 52.0 52.2 55.0 62.0 69.0 75.8 77.

 Hayden Island 12 53.0 53.3 55.2 59.0 66.0 71.0 71.

 Columbia City 12 48.0 48.3 51.2 54.5 61.5 66.4 67.

 Beaver 11 44.0 45.0 51.0 53.0 59.0 69.4 71.

 Willamette River 14 15.0 16.5 21.8 25.0 27.0 28.0 29.

 Multnomah Channel 11 23.0 23.2 31.0 36.0 46.0 48.6 49.

 Sandy River 11 12.0 12.0 13.0 15.0 22.0 24.4 25.

 Lewis River 4 16.0 -- -- 17.0 -- -- 20.

 Kalama River 4 20.0 -- -- 23.5 -- -- 24.

 Cowlitz River 4 25.0 -- -- 26.5 -- -- 27.

 All Sites 94 12.0 16.5 24.0 46.5 56.2 66.0 77.

Calcium

 Warrendale 11 16.0 16.0 16.0 17.0 20.0 21.0 21.

 Hayden Island 12 15.0 15.3 16.0 17.0 19.3 20.7 21.

 Columbia City 12 14.0 14.0 14.3 15.5 17.8 20.7 21.

 Beaver 11 13.0 13.0 14.0 15.0 17.0 18.0 18.

 Willamette River 14 5.0 5.1 6.1 6.9 7.4 7.9 8.

 Multnomah Channel 11 5.4 5.6 6.8 9.7 13.0 14.8 15.

 Sandy River 1 6.0 -- -- 6.0 -- -- 6.

 Lewis River 4 4.0 -- -- 4.2 -- -- 4.

 Kalama River 4 4.6 -- -- 5.7 -- -- 6.

 Cowlitz River 4 7.7 -- -- 8.9 -- -- 9.

 All Sites 84 4.0 5.4 7.3 14.0 17.0 19.0 21.

Chloride

 Warrendale 11 2.0 2.0 2.1 3.0 3.8 4.0 4.

 Hayden Island 12 1.9 2.0 2.7 3.5 4.3 5.0 5.

 Columbia City 12 2.8 2.9 3.9 4.2 4.5 4.6 4.

 Beaver 11 3.1 3.3 4.7 5.0 5.6 6.1 6.

 Willamette River 12 3.2 3.3 3.7 4.3 5.8 6.3 6.

 Multnomah Channel 11 4.3 4.4 4.9 6.4 9.1 13.1 14.

 Sandy River 4 1.6 -- -- 2.0 -- -- 2.

 Lewis River 4 1.6 -- -- 1.8 -- -- 1.

 Kalama River 4 2.5 -- -- 3.7 -- -- 4.
72

Chloride

 Cowlitz River 4 4.1 -- -- 5.5 -- -- 5.

 All Sites 85 1.6 2.1 3.0 4.1 5.0 6.2 14.

Fluoride

 Warrendale 11 .1 .1 .1 .1 .2 .2 .

 Hayden Island 12 .1 .1 .1 .1 .2 .2 .

 Columbia City 12 <.1 <.1 .1 .1 .2 .2 .

 Beaver 11 <.1 <.1 .1 .1 .2 .2 .

 Willamette River 12 <.1 <.1 <.1 <.1 <.1 <.1 <.

 Multnomah Channel 11 .1 <.1 <.1 <.1 .1 .2 .

 Sandy River 4 <.1 -- -- <.1 -- -- <.

 Lewis River 4 <.1 -- -- <.1 -- -- .

 Kalama River 4 <.1 -- -- <.1 -- -- <.

 Cowlitz River 4 <.1 -- -- <.1 -- -- <.

 All Sites 85 <.1 <.1 <.1 .1 .1 .2 .

Magnesium

 Warrendale 11 4.2 4.2 4.6 5.0 5.8 6.0 6.

 Hayden Island 12 4.0 4.1 4.5 4.8 5.3 6.0 6.

 Columbia City 12 3.7 3.9 4.2 4.4 5.2 6.0 6.

 Beaver 11 3.8 3.8 3.9 4.4 5.1 5.2 5.

 Willamette River 14 1.6 1.6 2.0 2.2 2.4 2.6 2.

 Multnomah Channel 11 1.8 1.9 2.3 3.1 3.8 4.3 4.

 Sandy River 1 2.3 -- -- 2.3 -- -- 2.

 Lewis River 4 1.0 -- -- 1.1 -- -- 1.

 Kalama River 4 1.2 -- -- 1.5 -- -- 1.

 Cowlitz River 4 1.7 -- -- 1.9 -- -- 2.

 All Sites 84 1.0 1.6 2.2 4.0 4.8 5.5 6.

Potassium

 Warrendale 11 .9 .9 1.0 1.2 1.3 1.4 1.

 Hayden Island 12 .9 .9 1.1 1.2 1.3 1.4 1.

 Columbia City 12 0.7 0.8 1.0 1.1 1.3 1.3 1.

 Beaver 11 .9 .9 1.1 1.2 1.3 1.3 1.

 Willamette River 14 .5 .6 .7 .8 .9 1.1 1.

 Multnomah Channel 11 .7 .7 .8 1.1 1.2 1.2 1.

Table 25. Distribution of major-ion concentrations in filtered and unfiltered water, lower Columbia River Basin, O

Washington, 1994—Continued

 [All measurements were performed on filtered-water samples, except specific conductance which was determined from an unfiltered-wa

term “filtered water” is an operational definition referring to the chemical analysis of that portion of a water-suspended sediment sample 

through a nominal 0.45-micrometer filter; conversely, the term “unfiltered water” refers to the chemical analysis of a water sample that has n

or centrifuged, nor in any way altered from the original matrix; to avoid statistical bias that may be associated with constituents analyzed 

at a site, only one element concentration per month was statistically summarized; values are reported in milligrams per liter, except wher

otherwise; see table 7 for full site names; -- indicates fewer than 6 samples collected, therefore the percentile was not calculated; <, less t

 Site name

Number

of

samples

Minimum

value

Value at indicated percentile Maxim

val

10 25 50 75 90
73

Potassium—Continued

 Sandy River 1 .9 -- -- .9 -- -- .

 Lewis River 4 .4 -- -- .4 -- -- .

 Kalama River 4 .3 -- -- .5 -- -- .

 Cowlitz River 4 .7 -- -- .8 -- -- .

 All Sites 84 .3 .5 .8 1.1 1.2 1.3 1.

Silica

 Warrendale 11 5.0 5.3 7.6 8.5 8.9 9.6 9.

 Hayden Island 12 5.4 5.9 7.4 8.7 9.7 10.0 10.

 Columbia City 12 6.3 6.6 7.4 9.4 10.0 11.0 11.

 Beaver 11 6.9 7.0 8.1 9.2 11.0 11.0 11.

 Willamette River 12 13.0 13.0 14.0 14.5 16.0 16.7 17.

 Multnomah Channel 11 8.2 8.5 10.0 13.0 15.0 16.8 17.

 Sandy River 4 17.0 -- -- 18.0 -- -- 21.

 Lewis River 9 6.5 6.5 6.7 6.8 6.9 7.0 7.

 Kalama River 10 5.0 5.1 6.6 7.7 8.7 19.8 21.

 Cowlitz River 10 5.3 5.4 6.4 6.7 7.1 13.3 14.

 All Sites 102 5.0 6.5 7.0 8.9 12.3 16.0 21.

Sodium

 Warrendale 11 3.7 3.8 4.3 6.1 6.8 7.6 7.

 Hayden Island 12 4.1 4.2 5.0 6.2 7.1 7.9 8.

 Columbia City 12 4.0 4.3 6.0 6.4 6.9 7.6 7.

 Beaver 11 4.8 5.1 6.3 7.1 7.5 7.7 7.

 Willamette River 14 3.4 3.5 4.7 5.8 7.9 9.3 9.

 Multnomah Channel 11 3.9 4.1 5.6 7.1 9.7 11.6 12.

 Sandy River 1 5.2 -- -- 5.2 -- -- 5.

 Lewis River 4 3.0 -- -- 3.1 -- -- 3.

 Kalama River 4 3.1 -- -- 4.3 -- -- 4.

 Cowlitz River 4 6.6 -- -- 8.2 -- -- 8.

 All Sites 84 3.0 3.8 4.9 6.3 7.2 8.5 12.

Specific conductance, in microsiemens per centimeter

 Warrendale 11 125.5 127.0 138.0 153.0 171.0 179.6 180.

 Hayden Island 12 125.2 128.3 140.5 150.3 168.7 187.1 191.

 Columbia City 11 126.1 126.5 133.3 145.9 152.2 172.0 175.

Table 25. Distribution of major-ion concentrations in filtered and unfiltered water, lower Columbia River Basin, O

Washington, 1994—Continued

 [All measurements were performed on filtered-water samples, except specific conductance which was determined from an unfiltered-wa

term “filtered water” is an operational definition referring to the chemical analysis of that portion of a water-suspended sediment sample 

through a nominal 0.45-micrometer filter; conversely, the term “unfiltered water” refers to the chemical analysis of a water sample that has n

or centrifuged, nor in any way altered from the original matrix; to avoid statistical bias that may be associated with constituents analyzed 

at a site, only one element concentration per month was statistically summarized; values are reported in milligrams per liter, except wher

otherwise; see table 7 for full site names; -- indicates fewer than 6 samples collected, therefore the percentile was not calculated; <, less t

 Site name

Number

of

samples

Minimum

value

Value at indicated percentile Maxim

val

10 25 50 75 90
74

Specific conductance, in microsiemens per centimeter—Continued

 Beaver 11 121.9 122.5 129.8 149.0 156.0 169.4 171.

 Willamette River 14 56.8 57.8 77.5 86.0 93.0 130.5 158.

 Multnomah Channel 11 61.4 63.7 83.9 124.7 138.0 145.9 147.

 Sandy River 12 27.0 27.9 38.2 46.0 63.7 74.7 76.

 Lewis River 10 40.0 40.2 42.7 45.5 50.0 54.8 55.

 Kalama River 11 33.0 34.8 45.0 48.0 60.0 68.0 68.

 Cowlitz River 11 78.0 78.4 83.0 98.0 114.0 115.0 115.

 All Sites 114 27.0 43.5 58.4 106.5 147.0 161.5 191.

Sulfate

 Warrendale 11 9.0 9.0 9.5 12.0 14.0 14.0 14.

 Hayden Island 12 8.8 8.9 10.2 11.0 12.8 14.7 15.

 Columbia City 12 9.0 9.2 9.6 10.5 12.0 13.7 14.

 Beaver 11 9.0 9.2 10.0 11.0 12.0 13.8 14.

 Willamette River 12 2.7 2.7 3.4 4.3 5.1 5.7 5.

 Multnomah Channel 11 3.1 3.3 4.2 6.8 8.5 9.9 10.

 Sandy River 4 2.6 -- -- 5.0 -- -- 6.

 Lewis River 4 1.9 -- -- 2.1 -- -- 2.

 Kalama River 4 1.1 -- -- 1.5 -- -- 1.

 Cowlitz River 4 12.0 -- -- 15.0 -- -- 15.

 All Sites 85 1.1 2.4 4.6 9.6 12.0 14.0 15.

Total dissolved solids, residue on evaporation at 180 degrees Celsius

 Warrendale 11 77.0 77.2 85.0 89.0 100.0 108.6 109.

 Hayden Island 12 72.0 74.1 86.2 90.0 98.7 114.1 115.

 Columbia City 12 70.0 72.4 81.0 85.0 102.0 114.3 117.

 Beaver 11 80.0 80.2 83.0 88.0 96.0 104.4 105.

 Willamette River 14 34.0 41.5 54.7 64.5 77.0 87.5 89.

 Multnomah Channel 11 56.0 56.4 60.0 78.0 82.0 87.6 88.

 Sandy River 12 31.0 31.6 36.0 44.0 57.0 66.1 67.

 Lewis River 9 36.0 36.0 38.0 40.0 45.0 75.0 75.

 Kalama River 10 37.0 37.3 40.7 49.5 59.7 108.8 114.

 Cowlitz River 10 65.0 65.1 66.7 74.5 81.7 88.5 89.

 All Sites 112 31.0 40.0 57.0 78.0 88.0 100.0 117.

Table 25. Distribution of major-ion concentrations in filtered and unfiltered water, lower Columbia River Basin, O

Washington, 1994—Continued

 [All measurements were performed on filtered-water samples, except specific conductance which was determined from an unfiltered-wa

term “filtered water” is an operational definition referring to the chemical analysis of that portion of a water-suspended sediment sample 

through a nominal 0.45-micrometer filter; conversely, the term “unfiltered water” refers to the chemical analysis of a water sample that has n

or centrifuged, nor in any way altered from the original matrix; to avoid statistical bias that may be associated with constituents analyzed 

at a site, only one element concentration per month was statistically summarized; values are reported in milligrams per liter, except wher

otherwise; see table 7 for full site names; -- indicates fewer than 6 samples collected, therefore the percentile was not calculated; <, less t

 Site name

Number

of

samples

Minimum

value

Value at indicated percentile Maxim

val

10 25 50 75 90
75

concentrations observed in rivers throughout the

world (14, 3.7, 5.7, 1.8, 6.8, 9.6, and 81 mg/L,

respectively; Hem, 1989). On the basis of the

historical data in the lower Columbia River Basin

(STORET data retrieval, 1947–93 WY), the median

concentrations of Ca, Mg, Na, K, Cl, SO4, and TDS

(6.3, 1.9, 4.0, 0.7, 3.7, 3.4, and 50 mg/L,

respectively) historically were lower than

measurements in this study. The higher

concentrations in 1994 reflect the limited dilution

capability of the tributaries during low-streamflow

conditions. Figure 28 provides a spatial perspective

of historical TDS data in the lower Columbia River

Basin on the basis of their 90th-percentile values.

The historical data were grouped into subbasins and

units for statistical purposes only; these maps do

not imply that the indicated TDS concentration

existed everywhere in a given unit. The maps do

show in a general way the historical TDS concentrations of different areas of the lower Columbia

River Basin, as recorded by the sampling done. As

expected, the highest TDS values (90th percentile:

270 mg/L) were in the estuary where seawater

mixes with river water. The next highest subbasins

were the Willamette River and the Lewis River

subbasins (90th percentiles: 158 and 161 mg/L,

respectively), while the Cowlitz River subbasin had

the lowest TDS values (90th percentile: 76 mg/L).

Specific conductance is a measure of the

ability of water to conduct an electrical charge and

is related to the concentration of major ions

dissolved in water. In most waters, it can be related

to the TDS concentration by multiplying by a factor

in the range 0.55 to 0.75 (Hem, 1989, p. 67). In

1994, the median specific conductance in the

Columbia River main stem ranged from 153 μS/cm

(microsiemens per centimeter) in the Columbia

River at Warrendale to 149 μS/cm in the Columbia

River at Beaver Army Terminal (table 25). The

median specific conductance during this study in the

Willamette River at Portland was 86 μS/cm. The

lower specific conductance in the Willamette River

was primarily a result of lower Ca, Mg, and HCO3

concentrations. The median Ca concentration in the

Willamette River at Portland (6.9 mg/L), for

example, was about one-half that in the Columbia

River at Beaver Army Terminal.

Figure 28. Spatial distribution of 90th-percentile values for

total dissolved solids by subbasin or unit, lower Columbia

River Basin, Oregon and Washington, 1947-93..

Map

Symbol Subbasin or unit name Numsam

A Lower Columbia (estuary) Unit 

B Lower Columiba-Clatskanie 1

C Cowlitz River Subbasin 

D Lewis River Subbasin 

E Lower Columbia-Sandy, Washington 

F Lower Willamette Unit 1

G Lower Columbia-Sandy, Oregon 7

H Willamette River Subbasin 4

C

G

A

B

D

F

E

H

Kalama River

Cowlitz

River

RIVER

River

Sandy

Lewis River

River

Willamette

COLUMBIA

R A N G E

C O A S T

Vancouver

Kalama

Longview

Bonne

Dam

Eugene

Government

 Camp

Salem

Portland

Rainier

Prescott

Goble

Altoona

Wauna

Warrend

Bradwood

Astoria

Cougar

10 20 30 MILES

0 10 20 30 KILOMETERS

0

124 123 122 47

46

45

44

EXPLANATION

Total dissolved solids

 Less than 100 milligrams per liter

 More than or equal to 100 and less than 150 milli

 More than or equal to 150 and less than 200 milli

 More than or equal to 200 milligrams per liter

Subbasin or unit border

Basin border

A Subbasin or unit name
76

The ionic composition of water in the lower

Columbia River was relatively unchanged between

Warrendale (RM 141) and Beaver Army Terminal

(RM 53.8). In this reach, Ca and Mg were the

dominant cations and HCO3 was the dominant anion

(fig. 29). As an example, Ca accounted for as much

as 60 percent of the cation milliequivalents in the

Columbia River at Beaver Army Terminal.

Willamette River water, however, tends to have

smaller proportions of Ca and HCO3 and higher

proportions of Na and Cl when compared to the

Lower Columbia River. This may be a result of

urban effects.

Although variations in median specific

conductance along the main stem were small in

1994, some seasonal variations do exist. During the

fall months, specific conductance decreased

between the Columbia River at Warrendale and the

Columbia River at Beaver Army Terminal. The

80

PERCENT

PERCENT

PERCENT

Columbia River at Warrendale

Willamette River at Portland

Columbia River at Beaver Army Terminal

EXPLANATION

SULFATE

SODIUM + POTASSIUM

CARBONATE + BICARBONATE

SULFATE + CHLORIDE

CALCIUM + MAGNESIUM

0 0

20

40

60

20

40

60

80

60

40

20

20

40

60

80

80

100

100

CALCIUM

80

60

40

20

0

0

20

40

60

80

100

0

20

40

60

80

100

100

CHLORIDE

0

20

40

60

80

100

60

40

20

80

100

0

0

20

40

60

80

100

MAGNESIUM

Figure 29. Major-ion composition in the Columbia River at Warrendale, Willamette River at Portland, and Columbia Riv

Army Terminal, lower Columbia River Basin, Oregon and Washington, 1994.

specific-conductance gradient in November 

which was typical for October and Decembe

showed that specific conductance decreased

37 μS/cm between Warrendale (RM 141) and 

Army Terminal (RM 53.8) (fig. 30); Ca conc

trations between these sites also decreased b

similar proportions. The decreasing conducti

the fall coincide with an increase in the propo

Willamette River water entering the main ste

101.5) between Warrendale and Beaver Arm

Terminal. Ratios of mean daily streamflows

(Willamette River at Portland: Columbia Riv

Warrendale) that coincide with water-quality

measurements ranged from 0.68 to 0.84 in fa

1994. These ratios underscore the diluting ca

of the Willamette River’s low-conductance w

In contrast, during the summer months, the r

mean daily streamflows are less than 0.1, an

discharge of low-conductance water from th

Willamette River has no measurable effect o
77

specific conductance in the main stem.

Consequently, from July to September of 1994,

specific conductance varied little in the main stem.

In August of 1994, for example, specific

conductance along the main stem is nearly constant

(fig. 30).

On the basis of the hydrologic connectivity

between the Willamette River and Multnomah

Channel, only small differences in specific

conductance might be expected between the

Willamette River and Multnomah Channel. Specific

conductance, however, differs considerably between

these sites and at times is related to the passage of

Columbia River water through Multnomah Channel

and at other times is related to local point and

0

200

20

40

60

80

100

120

140

160

180

MAIN STEM

TRIBUTARY

Multnomah Channel

Willamette River

160 40 140 120 100 80 60 40

RIVER MILE

0

200

20

40

60

80

100

120

140

160

180

NOVEMBER

Multnomah Channel

Willamette River

SPECIFIC CONDUCTANCE, IN MICROSIEMENS PER CENTIMETER

Figure 30. Specific conductance in the main stem and

tributaries during August and November, lower Columbia

River Basin, Oregon and Washington, 1994. (Willamette

River = Willamette River at Portland, Oregon; Multnomah

Channel = Multnomah Channel near mouth at St. Helens,

Oregon)

AUGUST nonpoint sources. The major-ion compositio

throughout Multnomah Channel is generally 

same as that in the Willamette River at Portl

differs from the Columbia River near Colum

(RM 84) (fig. 31), which is located just dow

from the mouth of the Multnomah Channel (

86.3). The similarity in the composition of m

ions between the Willamette River and Mult

Channel suggests that the Willamette River 

dominant source of water throughout Multno

Channel.

Concentration distributions of Ca, Mg, 

Cl, SO4, and TDS in Multnomah Channel ex

concentrations in the Willamette River (tabl

which may reflect the influence of local poin

nonpoint sources. Local point sources affect

Multnomah Channel include effluents from t

of Scappoose’s sewage-treatment plant and e

from Sauvie Island Moorage Company’s sew

treatment plant (table 46, at back of report; f

Nonpoint sources include agricultural runoff 

the southern portion of Sauvie Island and al

left bank of Multnomah Channel, as well as 

wastes associated with grazing within Sauvi

Island’s northern wetlands area. Concentrati

Na and Cl in Multnomah Channel represent

concentration maxima for the 10 sites sampl

1994. Na and Cl are indices of human/anima

and commonly are associated with effluents 

sewage-treatment plants (Fair and Geyer, 19

549). Concentrations of Na and Cl were high

Multnomah Channel from May to October, a 

when streamflow in the Willamette River is 

the potential effects from local point and no

sources are high.

Although Columbia River water was at 

present in Multnomah Channel, the Columb

cannot account for the high major ion conce

trations. From May to September, Columbia 

waters may mix with waters in Multnomah C

by flowing up the Willamette River (during 

tide) and down Multnomah Channel (Ricker

others, 1976). Additionally, the lower silica

concentrations, typical of Columbia River w

confirm the presence of Columbia River wat

Multnomah Channel from May through Sept

1994 (fig. 32). However, during the time wh

Columbia River water was resident in Multn

Channel, major-ion concentrations in the Co
78

River at Warrendale and Columbia River at Hayden

Island were small and cannot account for the high

Na and Cl concentrations in Multnomah Channel.

Additionally, the small Na and Cl concentrations in

the Columbia River main stem in the vicinity of

Portland’s sewage-treatment plant (RM 105.5)

suggest that Na and Cl discharges from Portland’s

plant are diluted, and hence, are not a source of ions

to Multnomah Channel as a result of streamflowreversal processes.

Specific conductance was selected as a 

ion surrogate for the purpose of examining t

water quality; it is an overall measure of ion

composition. Results of the seasonal Kendal

test for specific conductance for the period 1

indicate that significant (ρ < 0.05) downwar

exist in the Columbia River at Warrendale (t

at back of report). Both nonflow- and flow-a

methods resulted in a 0.5-percent decrease p

in the median of 160 μS/cm. A decrease of t

magnitude, for the nonflow adjusted trend, e

COLUMBIA RIVER AT COLUMBIA CITY

MULTNOMAH CHANNEL NEAR MOUTH AT ST. HELENS

0

WILLAMETTE RIVER AT PORTLAND

PERCENT

PERCENT

PERCENT

PERCENT

PERCENT

PERCENT

PERCENT

PERCENT

PERCENT

SODIUM + POTASSIUM

SODIUM + POTASSIUM

SODIUM + POTASSIUM

CHLORIDE

CARBONATE + BICARBONATE

20

40

80

100

CALCIUM + MAGNESIUM

SULFATE + CHLORIDE

0 0

20

40

60

80

80

60

40

20

20

40

60

80

20

40

60

80

100

100

CALCIUM

MAGNESIUM

60

0

20

40

60

80

100

100

80

60

40

20

0

0

20

40

60

80

100

100

80

60

40

20

0

0

20

40

60

80

100

SULFATE

CARBONATE + BICARBONATE

CALCIUM + MAGNESIUM

SULFATE + CHLORIDE

MAGNESIUM

0

80

60

40

20

20

40

60

80

20

40

60

80

CARBONATE + BICARBONATE

CALCIUM + MAGNESIUM

SULFATE + CHLORIDE

MAGNESIUM

0 0

20

40

60

20

40

60

80

80

60

40

20

20

40

60

80

80

100

100

CALCIUM

0

20

40

60

80

100

0

20

40

60

80

100

CHLORIDE

100

80

60

40

20

0

0

20

40

60

80

100

100

80

60

40

20

0

0

20

40

60

80

100

SULFATE

0

20

40

60

80

100

100

CALCIUM

0

20

40

60

80

100

0

20

40

60

80

100

CHLORIDE

100

80

60

40

20

0

6

80

100

100

80

60

40

20

0

0

20

40

60

80

Figure 31. Major-ion composition in the Columbia River near Columbia City, Willamette River at Portland, and Multno

Channel near mouth at St. Helens, lower Columbia River Basin, Oregon, 1994.
79

to a decrease of about 1 μS/cm/year at Warrendale.

No significant trends in specific conductance were

found at the Willamette River at Portland for the

period 1974–95. As expected, TDS, which is related

proportionally to specific conductance, also had

significant (ρ < 0.05) downward trends at

Warrendale for both nonflow-adjusted and flowadjusted methods. The median TDS concentration

(96 mg/L) for the nonflow-adjusted trends, for

example, decreased by 0.6 percent per year (-0.61

mg/L/year) at Warrendale for the period 1973–94.

Monthly and annual mean daily load estimates

were calculated using the ESTIMATOR program for

TDS in the Columbia River at Warrendale,

Columbia River at Beaver Army Terminal, and

Willamette River at Portland (table 26). In 1994, the

annual TDS load increased between the Columbia

River at Warrendale (RM 141) and the Columbia

River at Beaver Army Terminal (RM 53.8). In this

reach, the Willamette River alone accounted for 38

percent of the difference in annual loads between

Warrendale and Beaver. Additionally, the monthly

mean daily TDS loads at all three sites varied

seasonally with streamflow; higher TDS loads were

associated with higher streamflow conditions. In the

Willamette River, for example, the high-streamflow

months of fall and winter represented 76 percent of

the annual streamflow and 74 percent of the annual

TDS load. In contrast, the low-streamflow months

J F M A M J J A S O N D

1994

4

24

8

12

16

20

SILICA, IN MILLIGRAMS PER LITER

COLUMBIA CITY

WILLAMETTE RIVER

MULTNOMAH CHANNEL

Figure 32. Concentrations of silica in the Willamette River

at Portland, Multnomah Channel near mouth at St. Helens,

and Columbia River near Columbia City, lower Columbia

River Basin, Oregon, 1994. (Willamette River = Willamette

River at Portland, Oregon; Multnomah Channel =

Multnomah Channel near mouth at St. Helens, Oregon;

Columbia River near Columbia City, Oregon)

of summer represented only 8 percent of the 

streamflow and 9 percent of the annual TDS 

The Willamette River at Portland accou

most of the difference in monthly mean dail

loads between the Columbia River at Warren

Columbia River near Beaver Army Terminal 

the spring and summer months (April to Sep

(table 26). During these months, for exampl

monthly mean daily loads in the Willamette 

account for 57 to 100 percent of the differen

average, the proportion of load contribution 

Columbia River between Warrendale and Be

Army Terminal attributable to the Willamett

is 71 percent during the spring and summer 

and 38 percent during the fall and winter mo

(October to March). The fall and winter mon

proportion is identical to that based on the a

mean daily load but is considerably differen

the 71 percent during the spring and summe

months. The higher proportion of load for th

Willamette River during the spring and summ

months probably reflects the large number o

and nonpoint sources affecting TDS in the

Willamette River, in comparison to other trib

in the lower Columbia River. The higher pro

of load contribution of the Willamette River 

Columbia River, especially in July and Augu

period when streamflow on the Willamette i

yearly low) implies that summer TDS loads 

small in the other lower Columbia River trib

To underscore the minor effect of other lowe

Columbia River tributaries, the Kalama Rive

September 6, 1994, accounted for only 1 per

the difference between the September mean 

loads for Warrendale and Beaver. The Cowli

was more significant, accounting for 34 perc

the difference in TDS load but is small in re

the 75-percent contribution of the Willamett

Trace Elements

Median concentrations of most trace el

in filtered-water samples at the fixed sites sam

1994 were generally similar to background

concentrations in North American streams, a

as concentrations found in inland waters thr

the world (table 27). Iron, however, is an ex

On the basis of historical data (1951–93), th

interquartile range for iron concentrations in 

lower Columbia River Basin was 20 to 130 μ
80

far exceeded the interquartile range of 14 to 48 μg/L

for sites sampled in 1994. The high iron concentrations, rather than being indicative of a trend over

time, are the result of a disproportionately high

number of sites sampled historically in the

Willamette River Basin. The Willamette River,

both historically and in 1994, was a source of

high concentrations of filtered iron to the lower

Columbia River. In 1994, for example, the

interquartile range for filtered-water iron concentrations in the Willamette River at Portland was 49

to 182 μg/L, with a maximum concentration of

290 μg/L (table 28). In comparison, the interquartile

range for filtered-water iron concentrations in the

Columbia River at Warrendale for 1994 was only 7

to 18 μg/L. Additionally, the filtered-water iron

concentration in the Willamette River collected by

ODEQ on February 23, 1994, exceeded the waterquality criterion for the protection of human health

(table 47, at back of report).

Arsenic was detected in several filtered-water

samples in the lower Columbia River Basin. Its

presence is important, because it is a known

carcinogen to humans. Although median concentrations of arsenic were low (< 1 μg/L in 1994 and

1 μg/L from 1951 to 1993), a distinct pattern is

present when main-stem data are separated f

tributary data. In 1994, for example, arsenic 

consistently detected at a concentration of 1 

15 of 16 filtered-water determinations at all 

main-stem sites. Additionally, the detections 

present over a period of 1994 that spanned b

and low streamflow conditions. Based on all 

determinations (main stem and tributaries) i

arsenic concentrations in 38 percent of the s

exceeded ambient water-quality criteria for t

protection of human health and human-healt

advisories for drinking water (table 47, at ba

report). Based on historical data, arsenic als

detected consistently in the Columbia River 

Warrendale (1974–93) at RM 141 and Colum

River at Bradwood (1974–75) at RM 38.9 (U

Geological Survey NWIS retrieval). The abs

detectable arsenic in filtered-water samples 

tributaries of the lower Columbia River Basi

the presence of arsenic in the main stem sug

that sources of arsenic exist above the lower 

Data collected as part of the USGS’s NAWQ

Program support the presence of outside sour

example, the Yakima River (6,200 square mi

drainage), which flows into the Columbia Ri

RM 335.2, is an upstream source of arsenic. M

measurements of arsenic for the period 1987

Table 26. Calculated monthly and annual mean daily loads for total dissolved solids at selected sites, lower 

River Basin, Oregon, 1994

[Loads are reported in tons per day; see table 7 for full site names; all mean daily loads estimated using ESTIMATOR (Cohn and ot

Month Warrendale Willamette Beaver

January 39,000 6,200 53,000 44

February 45,000 4,700 56,000 43

March 41,000 5,100 53,000 42

April 43,000 4,000 50,000 57

May 52,000 2,000 54,000 100

June 43,000 1,900 46,000 63

July 32,000 1,300 34,000 65

August 21,000 1,300 23,000 65

September 18,000 1,500 20,000 75

October 24,000 2,100 29,000 42

November 31,000 6,200 51,000 31

December 39,000 9,700 77,000 26

Annual 36,000 3,800 46,000 38

Willamette

Beaver Warrendale – ----------------------------------------------------------------x100
81

Table 27. Comparison of selected major- and trace-element concentrations in filtered water in the lower Columbia River Basin to su[The term “filtered water” is an operational definition referring to the chemical analysis of that portion of a water-suspended sediment sample that passes through a statistical bias that may be associated with constituents analyzed more than once at a site, only one value per month was statistically summarized; values are reportNational Stream Accounting Network based on data from 300 sites across the United States; <, less than; --, no data; *, percentile value below method reporting lim

Element name

Background

concentrations,

inland watersa

aBased on a compendium of author contributions of inland-water chemistry worldwide (Forstner and Wittmann, 1979, p. 87).

North

American

streams b

(median)

bHem, 1989

NASQAN 1974-81c

cPercentiles are calculated from site-mean concentrations (Smith and others, 1987).

Lower Columbia River Basin (1951-93)d

dU.S. Environmental Protection Agency’s STOrage and RETrieval system (STORET), U.S. Geological Survey’s National Water Information System (NWIS)

Redmond, Washington, unpub. data, 1994

Lower C

Value at indicated

percentile

Number

of

samples

Value at indicated percentile Number

of

samples

25 50 75 25 50 75 90 

Aluminum < 30 -- -- -- -- 511 * 13 100 300 49 Antimony .1 -- -- -- -- 15 * * * * 41 Arsenic 2 <10 <1 1 3 607 * 1 1 2 41 Beryllium .01 <.3 -- -- -- 350 * * * * 41 Cadmium .07 1 -- -- -- -- -- -- -- -- 41 Chromium .5 5.8 -- -- -- -- -- -- -- -- 41 Cobalt .05 <1 -- -- -- 493 * * * * 48 Copper 1.8 -- -- -- -- 885 1 3 6 9 41 Iron < 30 -- 36 63 157 758 20 60 130 250 81 Lead .2 -- 3 4 6 876 * 1 5 13.3 41 Manganese <5 -- 11 24 51 1,121 * 10 40 150 82 Mercury .01 (e)

eMercury concentrations rarely exceed a few tenths of a microgram per liter (Hem, 1989).

-- -- -- -- -- -- -- -- 41 

Nickel .3 10 -- -- -- 527 * * * 5.5 48 Selenium .1 .2 <1 <1 1 501 * * * * 44 Silver .3 .3 -- -- -- 487 * * * * 48 

Zinc 10 20 12 15 21 1,753 * 10 20 38 41 
82

Table 28. Distribution of major- and trace-element concentrations in filtered water, lower Columbia River Basin

and Washington, 1994

[The term “filtered water” is an operational definition referring to the chemical analysis of that portion of a water-suspended sediment sa

that passes through a nominal 0.45-micrometer filter; to avoid statistical bias that may be associated with constituents analyzed more tha

at a site, only one element concentration per month was statistically summarized; values are reported in micrograms per liter; antimony, 

cadmium, cobalt, lead, nickel, and selenium are not included in this table, because no samples had values greater than the method reporting 

8 for method reporting limits; see table 7 for full site names; -- indicates fewer than 6 samples were collected, therefore the percentile was 

<, less than]

 Site name

Number

of

samples

Minimum

value

Value at indicated percentile Maxim

value 10 25 50 75 90

Aluminum

 Warrendale 4 5 -- -- 8 -- -- 17

 Hayden Island 4 6 -- -- 10 -- -- 24

 Columbia City 5 6 -- -- 20 -- -- 34

 Beaver 8 5 5 9 16 40 50 50

 Willamette River 8 5 5 8 56 148 170 170

Multnomah Channel 4 9 -- -- 13 -- -- 170

 Sandy River 4 12 -- -- 14 -- -- 29

 Lewis River 4 2 -- -- 4 -- -- 9

 Kalama River 4 6 -- -- 8 -- -- 10

 Cowlitz River 4 7 -- -- 20 -- -- 44

 All Sites 49 2 5 7 12 22 93 174

Arsenic

 Warrendale 4 1 -- -- 1 -- -- 1

 Hayden Island 4 1 -- -- 1 -- -- 1

 Columbia City 4 1 -- -- 1 -- -- 1

 Beaver 4 <1 -- -- 1 -- -- 1

 Willamette River 5 <1 -- -- <1 -- -- <1

Multnomah Channel 4 <1 -- -- <1 -- -- 1

 Sandy River 4 <1 -- -- <1 -- -- <1

 Lewis River 4 <1 -- -- <1 -- -- <1

 Kalama River 4 <1 -- -- <1 -- -- <1

 Cowlitz River 4 <1 -- -- <1 -- -- <1

 All Sites 41 <1 <1 <1 <1 1 1 1

Barium

 Warrendale 4 22 -- -- 24 -- -- 28

 Hayden Island 4 21 -- -- 23 -- -- 30

 Columbia City 4 20 -- -- 21 -- -- 23

 Beaver 8 17 17 18 20 21 21 21

 Willamette River 8 5 5 6 7 7 8 8

Multnomah Channel 4 6 -- -- 8 -- -- 11

 Sandy River 4 1 -- -- 2 -- -- 2

 Lewis River 4 1 -- -- 1 -- -- 1
83

Barium—Continued

 Kalama River 4 1 -- -- 1 -- -- 2

 Cowlitz River 4 2 -- -- 2 -- -- 3

 All Sites 48 1 1 2 7 21 24 30

Chromium

 Warrendale 4 <1 -- -- <1 -- -- 1

 Hayden Island 4 <1 -- -- 1 -- -- 2

 Columbia City 4 <1 -- -- <1 -- -- 1

 Beaver 4 <1 -- -- <1 -- -- 1

 Willamette River 5 <1 -- -- <1 -- -- <1

Multnomah Channel 4 <1 -- -- <1 -- -- 1

 Sandy River 4 <1 -- -- <1 -- -- <1

 Lewis River 4 <1 -- -- <1 -- -- <1

 Kalama River 4 <1 -- -- <1 -- -- 1

 Cowlitz River 4 <1 -- -- <1 -- -- <1

 All Sites 41 <1 <1 <1 <1 <1 1 2

Copper

 Warrendale 4 1 -- -- 1 -- -- 3

 Hayden Island 4 <1 -- -- <1 -- -- 2

 Columbia City 4 1 -- -- 2 -- -- 2

 Beaver 4 <1 -- -- 1 -- -- 2

 Willamette River 5 <1 -- -- <1 -- -- 2

Multnomah Channel 4 1 -- -- 2 -- -- 3

 Sandy River 4 <1 -- -- <1 -- -- 1

 Lewis River 4 <1 -- -- <1 -- -- <1

 Kalama River 4 <1 -- -- 1 -- -- 2

 Cowlitz River 4 <1 -- -- 1 -- -- 2

 All Sites 41 <1 <1 <1 1 2 2 3

Iron

 Warrendale 11 2 3 7 9 18 24 25

 Hayden Island 12 5 5 8 10 17 33 39

 Columbia City 12 10 11 14 18 30 45 49

 Beaver 9 10 10 14 20 44 53 53

 Willamette River 10 33 34 49 104 182 280 290

Table 28. Distribution of major- and trace-element concentrations in filtered water, lower Columbia River Basin

and Washington, 1994—Continued

[The term “filtered water” is an operational definition referring to the chemical analysis of that portion of a water-suspended sediment sa

that passes through a nominal 0.45-micrometer filter; to avoid statistical bias that may be associated with constituents analyzed more tha

at a site, only one element concentration per month was statistically summarized; values are reported in micrograms per liter; antimony, 

cadmium, cobalt, lead, nickel, and selenium are not included in this table, because no samples had values greater than the method reporting 

8 for method reporting limits; see table 7 for full site names; -- indicates fewer than 6 samples were collected, therefore the percentile was 

<, less than]

 Site name

Number

of

samples

Minimum

value

Value at indicated percentile Maxim

value 10 25 50 75 90
84

Iron—Continued

Multnomah Channel 11 14 14 27 43 120 154 160

 Sandy River 4 38 -- -- 53 -- -- 66

 Lewis River 4 25 -- -- 38 -- -- 48

 Kalama River 4 17 -- -- 19 -- -- 20

 Cowlitz River 4 44 -- -- 61 -- -- 73

 All Sites 81 1 8 14 25 48 120 290

Manganese

 Warrendale 11 <1 <1 <1 <1 <1 2 2

 Hayden Island 12 <1 <1 1123 3

 Columbia City 12 <1 <1 <1234 4

 Beaver 9 <1 <1 <1 1 3 3 3

 Willamette River 11 <1 1 6 8 11 16 16

Multnomah Channel 11 <1 <1 2 4 11 20 20

 Sandy River 4 3 -- -- 4 -- -- 4

 Lewis River 4 3 -- -- 12 -- -- 12

 Kalama River 4 <1 -- -- 2 -- -- 4

 Cowlitz River 4 5 -- -- 6 -- -- 7

 All Sites 82 <1 <1 <1 2 5 11 20

Mercury

 Warrendale 4 <.1 -- -- <.1 -- -- <.1

 Hayden Island 4 <.1 -- -- <.1 -- -- <.1

 Columbia City 4 <.1 -- -- <.1 -- -- <.1

 Beaver 4 <.1 -- -- <.1 -- -- 3.6

 Willamette River 5 <.1 -- -- <.1 -- -- .6

Multnomah Channel 4 <.1 -- -- <.1 -- -- .1

 Sandy River 4 <.1 -- -- <.1 -- -- <.1

 Lewis River 4 <.1 -- -- <.1 -- -- <.1

 Kalama River 4 <.1 -- -- <.1 -- -- <.1

 Cowlitz River 4 <.1 -- -- <.1 -- -- <.1

 All Sites 41 <.1 <.1 <.1 <.1 <.1 <0.1 3.6

Molybdenum

 Warrendale 4 <1 -- -- <1 -- -- 1

 Hayden Island 4 <1 -- -- <1 -- -- 1

Table 28. Distribution of major- and trace-element concentrations in filtered water, lower Columbia River Basin

and Washington, 1994—Continued

[The term “filtered water” is an operational definition referring to the chemical analysis of that portion of a water-suspended sediment sa

that passes through a nominal 0.45-micrometer filter; to avoid statistical bias that may be associated with constituents analyzed more tha

at a site, only one element concentration per month was statistically summarized; values are reported in micrograms per liter; antimony, 

cadmium, cobalt, lead, nickel, and selenium are not included in this table, because no samples had values greater than the method reporting 

8 for method reporting limits; see table 7 for full site names; -- indicates fewer than 6 samples were collected, therefore the percentile was 

<, less than]

 Site name

Number

of

samples

Minimum

value

Value at indicated percentile Maxim

value 10 25 50 75 90
85

Molybdenum—Continued

 Columbia City 4 <1 -- -- <1 -- -- 1

 Beaver 8 <1 <1 <1 3 5 5 5

 Willamette River 8 <1 <1 <1 3 5 10 10

Multnomah Channel 4 <1 -- -- <1 -- -- <1

 Sandy River 4 <1 -- -- <1 -- -- <1

 Lewis River 4 <1 -- -- <1 -- -- <1

 Kalama River 4 <1 -- -- <1 -- -- <1

 Cowlitz River 4 <1 -- -- <1 -- -- <1

 All Sites 48 <1 <1 <1 <1 <1 5 10

Uranium

 Warrendale 4 <1 -- -- <1 -- -- <1

 Hayden Island 4 <1 -- -- <1 -- -- 1

 Columbia City 4 <1 -- -- <1 -- -- <1

 Beaver 4 <1 -- -- <1 -- -- <1

 Willamette River 6 <1 <1 <1 <1 <1 <1 <1

Multnomah Channel 4 <1 -- -- <1 -- -- <1

 Sandy River 4 <1 -- -- <1 -- -- <1

 Lewis River 4 <1 -- -- <1 -- -- <1

 Kalama River 4 <1 -- -- <1 -- -- <1

 Cowlitz River 4 <1 -- -- <1 -- -- <1

 All Sites 42 <1 <1 <1 <1 <1 <1 1

Zinc

 Warrendale 4 <1 -- -- <1 -- -- 8

 Hayden Island 4 <1 -- -- 2 -- -- 4

 Columbia City 4 <1 -- -- 1 -- -- 2

 Beaver 4 <1 -- -- 3 -- -- 14

 Willamette River 5 1 -- -- 2 -- -- 2

Multnomah Channel 4 1 -- -- 2 -- -- 5

 Sandy River 4 1 -- -- 2 -- -- 2

 Lewis River 4 <1 -- -- <1 -- -- 3

 Kalama River 4 <1 -- -- 2 -- -- 2

 Cowlitz River 4 <1 -- -- <1 -- -- 1

 All Sites 41 <1 <1 <1 1 2 4 14

Table 28. Distribution of major- and trace-element concentrations in filtered water, lower Columbia River Basin

and Washington, 1994—Continued

[The term “filtered water” is an operational definition referring to the chemical analysis of that portion of a water-suspended sediment sa

that passes through a nominal 0.45-micrometer filter; to avoid statistical bias that may be associated with constituents analyzed more tha

at a site, only one element concentration per month was statistically summarized; values are reported in micrograms per liter; antimony, 

cadmium, cobalt, lead, nickel, and selenium are not included in this table, because no samples had values greater than the method reporting 

8 for method reporting limits; see table 7 for full site names; -- indicates fewer than 6 samples were collected, therefore the percentile was 

<, less than]

 Site name

Number

of

samples

Minimum

value

Value at indicated percentile Maxim

value 10 25 50 75 90
86

the terminus of the Yakima River Basin had a

median filtered-water arsenic concentration of 1μg/

L. Additionally, 25 percent of the time, the arsenic

concentration at the terminus of the basin was 2 μg/

L, and waters draining agricultural fields in the

Yakima River Basin had arsenic concen-trations as

high as 9 μg/L (Fuhrer and others, in press).

In 1994, chromium was detected in 8 of 16

filtered-water samples at the 4 main-stem sites

(table 29). In contrast, chromium was detected at

only 2 of 6 tributary sites and in only 2 of 25

determinations. Chromium was detected most

frequently in the Columbia River at Hayden Island,

where three of four filtered-water samples had

detectable concentrations ranging from 1 to 2 μg/L.

Several possible point sources of chromium exist

along the main stem of the Columbia River. These

sources include some chemical industries (Kalama

Chemical [RM 74] and Wacker Siltronic

Corporation [Willamette RM 6.6]), wood–treating

and wood-product industries (Allweather Wood

Treaters [RM 123.3] and Boise Cascade St. Helens

Veneer Mill [RM 86]), aluminum industries

(ALCOA [RM 103] and Reynolds Metal in

Troutdale [RM 120]), and miscellaneous facilities

(Pendleton Woolen Mills [RM 122.8] and the Gould

Superfund site [Willamette RM 7.0]). Table 47 (at

back of report) provides a more complete listing of

possible point-source contributions. Chromium was

detected only once in Multnomah Channel (August

8, 1994), and its detection coincided with a time

period in which surface water in the Columbia River

flows up the Willamette River and down Multnomah

Channel. The detection of chromium also coincides

with lower silica concentrations which are

indicative of the presence of Columbia River water

in Multnomah Channel (see the “Major Ions and

Related Measures Section” section for discussion).

None of the chromium detections, however,

exceeded ambient water-quality criteria or drinkingwater guidelines (table 49, at back of report).

Mercury was detected in filtered-water

samples in 3 of 41 determinations (table 29). It was

detected at the Multnomah Channel (0.1 μg/L),

Willamette River at Portland (0.6 μg/L), and

Columbia at Beaver Army Terminal (3.6 μg/L).

Mercury was detected in the Willamette River in

June and Beaver Army Terminal and Multnomah

Channel in August, with all detections occur

during low-streamflow conditions. Detection

low streamflows for most trace elements are 

expected, because trace elements discharged 

point sources are diluted to a lesser extent d

periods of extended low streamflow. Detecti

mercury are problematic given its ubiquitou

as a common field and laboratory contamina

and Mitchell, 1976, p. 9). The concentration

mercury detected in this study were well abo

0.01 μg/L reported by Forstner and Wittmann 

as a background concentration for inland wa

Also, suspended-sediment samples, which w

concurrently collected with filtered-water sa

lacked anomalies that would support the pre

high concentrations of filtered mercury. Des

these questions, filtered-water mercury conc

trations exceeded ambient water-quality crit

drinking-water criteria (table 47, at back of 

however, caution should be exercised in usin

data given mercury’s affinity to contaminate 

between the time of collection and processin

the laboratory, prior to analysis.

In 1994 and historically, higher concen

of filtered-water iron in the Willamette Rive

Portland were often associated with high str

flows which usually started in October. On

November 3, 1994, for example, the filtered

water iron concentration in the Willamette R

(290 μg/L) was 6 times that measured on Se

13, 1994, during the low-streamflow period. 

corresponding filtered-water iron load (120,

lbs/d [pounds per day]) on November 3, 199

about 50 times that measured on September 1

(2,400 lbs/d), during the low-flow period (ta

The filtered-water iron load during winter-hi

in the Willamette River also represents a lar

proportion of the filtered-water iron load in 

Columbia River. For the November 3, 1994

sampling, the filtered-water iron load in the

Willamette River is nearly 17 times that mea

November 8, 1994, in the Columbia River at

Warrendale (7,100 lbs/d). The large instanta

load and concentration of filtered-water iron 

November in the Willamette River undersco

significance of the Willamette River as a sou

iron during winter high streamflows. Similar

concentration patterns and trends in load als

for aluminum and, to a lesser extent, for ma
87

Table 29. Frequency of detection of selected major and trace elements in filtered water, lower Columbia River Basin, Orego[Method reporting limits (MRL) are reported in micrograms per liter; see table 7 for full site names; n, number of samples analyzed; --, not detected]

Element

name

MRL

Main stem Tributaries

Warrendale Hayden Island Columbia City Beaver Sandy River Willamette River Lewis River Multnomah Channel 

n = 4 n = 4 n = 4 n = 4 n = 4 n = 5 n = 4 n = 4 

Aluminum 1 4 4 4 4 4 5 3 4 Antimony 1 -- -- -- -- -- -- -- -- Arsenic 1 4 4 4 3 -- -- -- 1 Beryllium 1 -- -- -- -- -- -- -- -- Cadmium 1 -- -- -- -- -- -- -- -- Chromium 1 2 3 2 1 -- -- -- 1 Cobalt 1 -- -- -- -- -- -- -- -- Copper 1 4 2 4 3 1 3 -- -- Iron 3 4 4 4 4 4 5 4 4 Lead 1 -- -- -- -- -- -- -- -- Manganese 1 -- 3 1 2 4 4 3 3 Mercury .1 -- -- -- 1 -- 1 -- 1 Nickel 1 -- -- -- -- -- -- -- -- Selenium 1 -- -- -- -- -- -- -- -- Silver 1 -- -- -- -- -- -- -- -- Zinc 1 2 3 2 3 4 5 1 4 
88

Table 30. Instantaneous loads for major and trace elements for selected low and high streamflow conditions in the Columbia River at Portland, and Columbia River at Beaver Army Terminal, lower Columbia River Basin, Oregon, 1994[Loads are reported in pounds per day; ft3/s, cubic feet per second; Filt., filtered load; Sus., suspended load; F/S, filtered-water load divided by suspended load; the te

referring to the chemical analysis of that portion of a water-suspended sediment sample that passes through a nominal 0.45-micrometer filter; --, value could not be calcwas below the method reporting limit]

Element name

Columbia River at Warrendale Columbia River at Beaver Army Terminal Willame

High streamflow

(233,000 ft3/s)

June 15, 1994

Low streamflow

(93,800 ft3/s)

August 8, 1994

High streamflow

(234,000 ft3/s)

April 14, 1994

Low streamflow

(90,800 ft3/s)

August 11, 1994

High streamflow

(76,600 ft3/s)

November 3, 199

Filt. Sus. F/S Filt. Sus. F/S Filt. Sus. F/S Filt. Sus. F/S Filt. Sus. 

Al 6,000 920,000 0.01 4,000 130,000 0.03 59,000 1,100,000 0.05 4,400 270,000 0.02 66,000 2,900,000 Sb -- 20 -- -- 4 -- -- 30 -- -- 4 -- -- 40 As 1,000 100 10 500 20 25 -- 100 -- 500 30 17 -- 300 Ba 28,000 8,000 3.5 12,000 1,200 10 25,000 13,000 1.9 10,000 2,200 4.5 2,000 17,000 Be 1,000 -- -- -- -- -- -- -- -- -- -- -- -- 100 

Cd -- -- -- -- 4 -- -- 10 -- -- -- -- -- 10 Cr -- 700 -- 500 100 5 -- 800 -- 500 200 2.5 -- 2,400 

Co -- 200 -- -- 40 -- -- 300 -- -- 70 -- -- 900 Cu 1,000 600 1.7 500 100 5 -- 600 -- 500 200 2.5 800 2,100 Fe 11,000 570,000 .02 4,600 87,000 .05 60,000 620,000 .10 7,300 160,000 .05 120,000 2,000,000 Pb -- 400 -- -- 70 -- -- 300 -- -- 100 -- -- 1,200 Mn -- 18,000 -- -- 3,400 -- 800 14,000 .06 -- 5,900 -- 4,100 64,000 

Hg 100 2 50 -- -- -- -- 8 -- -- .7 -- -- 4 Mo -- 8 -- -- 1 -- -- 20 -- -- 2 -- -- 30 Ni -- 400 -- -- 60 -- -- 400 -- -- 100 -- -- 1,300 Se -- 8 -- -- -- -- -- 6 -- -- 2 -- -- 10 Ag -- 4 -- -- .8 -- -- 9 -- -- 1 -- -- 10 Ur -- 40 -- -- 7 -- -- 40 -- -- 10 -- -- 70 Zn -- 3,200 -- 500 600 .83 18,000 2,400 7.5 1,000 700 1.4 800 4,000 
89

The suspended-iron concentration (iron

concentration associated with the suspendedsediment fraction) on November 3, 1994, in the

Willamette River (6.1 percent) was about 45 percent

larger than that measured on November 8, 1994 in

Columbia River at Warrendale (4.2 percent).

Overall, suspended-iron concentrations in the

Willamette River were the highest for the 10 sites

sampled in the lower Columbia River Basin in 1994

(table 31). Unlike filtered-water iron

concentrations, suspended-iron concentrations were

similar during the winter high flows and the summer

low flows. However, suspended-sediment loads and,

consequently, suspended-iron loads were much

greater during periods of high flow than during

periods of low flow. The respective high- and lowstreamflow concentrations of suspended iron (6.1

and 5.2 percent) on November 3 and September 13

differed by only 0.9 percent, yet the respective

suspended-iron load during the high-flow sampling

in November (2,000,000 lbs/d) was more than 150

times that measured in September (13,000 lbs/d)

(table 30). The large difference in suspended-iron

load between seasons is the result of the large

differences in November and September suspendedsediment concentrations (81 mg/L and 5 mg/L,

respectively) and streamflows (76,000 ft3/s and

9,100 ft3/s, respectively).

The suspended form of iron is the dominant

transport phase in the lower Columbia River. During

high streamflows in the Columbia River at

Warrendale, the suspended-iron load exceeded the

filtered-water load by a factor of 50; during low

streamflows, the suspended load was still dominant,

exceeding the filtered-water load by a factor of 20.

Patterns similar to those for iron at Warrendale also

existed at other sites sampled in 1994. Additionally,

the suspended form is the major transport phase for

aluminum and manganese.

The significance of tributary loads of

suspended trace elements to the main stem of the

Columbia River was determined by comparing

instantaneous loads at tributary sites to

instantaneous loads in the Columbia River at

Warrendale. The summer low-streamflow months

were selected as the time period for comparing

loads, because they approximate steady-state

streamflow conditions to a greater extent (based on

present-study data) than the winter high-streamflow

months. Ideally, a winter high-streamflow period

would be best for comparing instantaneous l

because of the relation between suspended-s

transport and rain-induced high streamflows

however, samples collected for use in makin

intersite-load comparisons in this study were

sometimes separated by days and weeks. Al

during winter months, intrasite variations in 

streamflow and suspended-sediment concent

can be large over periods as long as days or 

During the low-streamflow period, the Willa

River and the Cowlitz River were the largest

contributors of suspended trace elements. Fo

example, the suspended-silver load during th

flow period in the Willamette River (0.5 lbs/

60 percent of the suspended load at Warrend

(0.8 lbs/day), even though the streamflow in 

Willamette River was only 10 percent of the

streamflow in the Columbia River at Warren

The Cowlitz River had suspended loads of n

(25 lbs/d), aluminum (23 tons/day), and anti

(1.2 lb/d) during low-flow conditions (3,230 

which were respectively, 42 percent, 35 perc

30 percent of the corresponding loads at War

yet the streamflow was only 3 percent of the 

flow at Warrendale (table 30). Conversely, th

Willamette River and the Cowlitz River wer

relatively small contributors of suspended zi

arsenic. The suspended zinc and arsenic load

the low-flow period in the Willamette River 

and 6 percent, respectively, of the suspended 

the Columbia River at Warrendale. Percenta

suspended zinc and arsenic were similarly lo

Cowlitz River. On the basis of tributary load

summer low-flow months, sources of suspen

silver, nickel, aluminum, and antimony exist 

lower Columbia Basin and the sources of su

zinc and arsenic exist outside of the lower b

Comparing transport phases (filtered-w

versus suspended) for several constituents, in

Sb, Be, Cd, Co, Pb, Hg, Se, and Ag, is probl

because of the large amount of censored dat

filtered-water determinations. In most cases 

trace elements in filtered-water samples wer

detected and quantified, however, the filtered

fraction was the dominant transport phase.

5A potential point source of silver in the lower W

River is the EPA Gould Superfund site (a former bat

ufacturing and recycling plant) managed by Canonie 

mental Services Corporation which is allowed to dis

to 4.1 μg/L silver under the NPDES program (table 4

of report).
90

Table 31. Distribution of major- and trace-element concentrations in suspended sediment, lower Columbia River 

Oregon and Washington, 1994

[Values are reported in micrograms per gram, except aluminum and iron which are in percent; see table 7 for full site names; -- indicates f

samples collected, therefore percentile not calculated; <, less than]

 Site name

Number

of

samples

Minimum

value

Value at indicated percentile Maxim

val

10 25 50 75 90

Aluminum, in percent

 Warrendale 4 6.4 -- -- 6.4 -- -- 6

 Hayden Island 4 6.5 -- -- 7.2 -- -- 8

 Columbia City 4 6.4 -- -- 6.7 -- -- 8

 Beaver 4 6.8 -- -- 7.1 -- -- 7

 Willamette River 4 7.4 -- -- 8.1 -- -- 8

Multnomah Channel 4 7.7 -- -- 8.0 -- -- 9

 Sandy River 4 5.9 -- -- 6.7 -- -- 7

 Lewis River 3 4.3 -- -- 4.7 -- -- 7

 Kalama River 4 4.9 -- -- 5.2 -- -- 6

 Cowlitz River 4 8.0 -- -- 8.2 -- -- 8

 All Sites 40 4.3 4.9 6.4 6.9 8.0 8.6 9

Iron, in percent

 Warrendale 4 4.0 -- -- 4.1 -- -- 4

 Hayden Island 4 4.1 -- -- 4.7 -- -- 6

 Columbia City 4 4.1 -- -- 4.3 -- -- 5

 Beaver 4 4.1 -- -- 4.2 -- -- 5

 Willamette River 4 5.2 -- -- 5.9 -- -- 6

Multnomah Channel 4 5.0 -- -- 5.3 -- -- 6

 Sandy River 4 3.0 -- -- 4.0 -- -- 4

 Lewis River 3 3.8 -- -- 3.9 -- -- 4

 Kalama River 4 3.3 -- -- 3.5 -- -- 4

 Cowlitz River 4 3.7 -- -- 3.9 -- -- 4

 All Sites 40 3.0 3.7 4.0 4.2 5.1 6.0 6

Antimony

 Warrendale 4 1.4 -- -- 1.6 -- -- 

 Hayden Island 4 1.1 -- -- 1.1 -- -- 

 Columbia City 4 .9 -- -- 1.3 -- -- 2

 Beaver 4 .9 -- -- 1.4 -- -- 2

 Willamette River 4 .4 -- -- .7 -- -- 

Multnomah Channel 4 .7 -- -- 1.0 -- -- 

 Sandy River 4 .4 -- -- .6 -- -- 4

 Lewis River 3 .3 -- -- 1.8 -- -- 2

 Kalama River 4 .4 -- -- .6 -- -- 7

 Cowlitz River 4 .2 -- -- .6 -- -- 2

 All Sites 40 .2 .4 .6 1.2 1.6 2.1 7
91

Arsenic

 Warrendale 4 8.0 -- -- 9.0 -- -- 1

 Hayden Island 4 6.0 -- -- 7.1 -- -- 8

 Columbia City 4 6.0 -- -- 8.4 -- -- 8

 Beaver 4 6.4 -- -- 8.6 -- -- 1

 Willamette River 4 2.6 -- -- 7.0 -- -- 8

Multnomah Channel 4 6.0 -- -- 6.9 -- -- 10

 Sandy River 4 2.2 -- -- 3.6 -- -- 12

 Lewis River 3 7.6 -- -- 9.4 -- -- 15

 Kalama River 4 3.5 -- -- 4.7 -- -- 5

 Cowlitz River 4 1.7 -- -- 3.2 -- -- 4

 All Sites 40 1.7 2.7 4.7 7.0 8.8 11.0 15

Beryllium

 Warrendale 4 1 -- -- 1 -- -- 

 Hayden Island 4 1 -- -- 2 -- -- 2

 Columbia City 4 1 -- -- 1 -- -- 2

 Beaver 4 1 -- -- 1 -- -- 2

 Willamette River 4 1 -- -- 2 -- -- 4

Multnomah Channel 4 1 -- -- 2 -- -- 3

 Sandy River 4 1 -- -- 1 -- -- 2

 Lewis River 3 1 -- -- 1 -- -- 2

 Kalama River 4 1 -- -- 1 -- -- 

 Cowlitz River 4 1 -- -- 1 -- -- 5

 All Sites 40 1 1 1 1 2 3 5

Cadmium

 Warrendale 4 1.0 -- -- 2.0 -- -- 2

 Hayden Island 4 1.0 -- -- 1.7 -- -- 5

 Columbia City 4 .8 -- -- 1.7 -- -- 7

 Beaver 4 .8 -- -- 1.3 -- -- 3

 Willamette River 4 .3 -- -- .4 -- -- 

Multnomah Channel 4 .3 -- -- 1.0 -- -- 

 Sandy River 4 .4 -- -- 1.0 -- -- 

 Lewis River 3 .5 -- -- .6 -- -- 

 Kalama River 4 .5 -- -- .9 -- -- 

 Cowlitz River 4 .2 -- -- 1.0 -- -- 

 All Sites 40 .2 .3 .8 1.0 1.3 2.3 7

Table 31. Distribution of major- and trace-element concentrations in suspended sediment, lower Columbia River 

Oregon and Washington, 1994—Continued

[Values are reported in micrograms per gram, except aluminum and iron which are in percent; see table 7 for full site names; -- indicates f

samples collected, therefore percentile not calculated; <, less than]

 Site name

Number

of

samples

Minimum

value

Value at indicated percentile Maxim

val

10 25 50 75 90
92

Chromium

 Warrendale 4 48 -- -- 55 -- -- 58

 Hayden Island 4 53 -- -- 58 -- -- 79

 Columbia City 4 56 -- -- 62 -- -- 72

 Beaver 4 54 -- -- 56 -- -- 67

 Willamette River 4 71 -- -- 76 -- -- 82

Multnomah Channel 4 75 -- -- 76 -- -- 78

 Sandy River 4 20 -- -- 33 -- -- 48

 Lewis River 3 23 -- -- 23 -- -- 35

 Kalama River 4 49 -- -- 52 -- -- 62

 Cowlitz River 4 20 -- -- 25 -- -- 3

 All Sites 40 20 23 34 56 70 78 82

Copper

 Warrendale 4 30 -- -- 41 -- -- 59

 Hayden Island 4 37 -- -- 63 -- -- 86

 Columbia City 4 40 -- -- 69 -- -- 83

 Beaver 4 42 -- -- 45 -- -- 260

 Willamette River 4 51 -- -- 64 -- -- 110

Multnomah Channel 4 48 -- -- 56 -- -- 70

 Sandy River 4 41 -- -- 74 -- -- 110

 Lewis River 3 45 -- -- 50 -- -- 9

 Kalama River 4 71 -- -- 80 -- -- 100

 Cowlitz River 4 41 -- -- 58 -- -- 66

 All Sites 40 30 40 46 60 78 99 260

Lead

 Warrendale 4 26.9 -- -- 32.0 -- -- 49

 Hayden Island 4 23.7 -- -- 27.0 -- -- 4

 Columbia City 4 26.2 -- -- 30.0 -- -- 36

 Beaver 4 20.1 -- -- 23.9 -- -- 50

 Willamette River 4 7.9 -- -- 22.5 -- -- 33

Multnomah Channel 4 24.0 -- -- 31.0 -- -- 49

 Sandy River 4 12.0 -- -- 19.0 -- -- 37

 Lewis River 3 12.0 -- -- 21.0 -- -- 2

 Kalama River 4 15.0 -- -- 16.8 -- -- 26

 Cowlitz River 4 2.2 -- -- 10.2 -- -- 15

 All Sites 40 2.2 12.0 15.4 24.5 30.0 40.6 50

Table 31. Distribution of major- and trace-element concentrations in suspended sediment, lower Columbia River 

Oregon and Washington, 1994—Continued

[Values are reported in micrograms per gram, except aluminum and iron which are in percent; see table 7 for full site names; -- indicates f

samples collected, therefore percentile not calculated; <, less than]

 Site name

Number

of

samples

Minimum

value

Value at indicated percentile Maxim

val

10 25 50 75 90
93

Manganese

 Warrendale 4 1,200 -- -- 1,500 -- -- 2,000

 Hayden Island 4 1,200 -- -- 1,450 -- -- 2,100

 Columbia City 4 1,200 -- -- 1,450 -- -- 1,800

 Beaver 4 1,100 -- -- 1,400 -- -- 2,000

 Willamette River 4 1,500 -- -- 2,950 -- -- 4,000

Multnomah Channel 4 1,900 -- -- 2,150 -- -- 2,600

 Sandy River 4 900 -- -- 1,500 -- -- 1,700

 Lewis River 3 2,100 -- -- 3,100 -- -- 5,000

 Kalama River 4 1,100 -- -- 1,400 -- -- 1,800

 Cowlitz River 4 1,100 -- -- 1,550 -- -- 2,300

 All Sites 40 900 1,110 1,300 1,650 2,100 3,910 5,700

Mercury

 Warrendale 3 .08 -- -- .17 -- -- 

 Hayden Island 3 .10 -- -- .17 -- -- 3

 Columbia City 4 .11 -- -- .14 -- -- 

 Beaver 4 .10 -- -- .16 -- -- 

 Willamette River 4 .11 -- -- .18 -- -- 

Multnomah Channel 4 .11 -- -- .12 -- -- 

 Sandy River 2 .09 -- -- .12 -- -- 

 Kalama River 2 .10 -- -- .18 -- -- 

 Cowlitz River 4 <.02 -- -- .09 -- -- 

 All Sites 30 .01 .08 .11 .15 .19 .70 3

Nickel

 Warrendale 4 26 -- -- 28 -- -- 3

 Hayden Island 4 28 -- -- 30 -- -- 36

 Columbia City 4 29 -- -- 30 -- -- 34

 Beaver 4 26 -- -- 28 -- -- 38

 Willamette River 4 34 -- -- 37 -- -- 38

Multnomah Channel 4 33 -- -- 34 -- -- 4

 Sandy River 4 25 -- -- 26 -- -- 76

 Lewis River 3 19 -- -- 23 -- -- 120

 Kalama River 4 29 -- -- 32 -- -- 96

 Cowlitz River 4 10 -- -- 18 -- -- 47

 All Sites 40 10 18 26 30 36 46 120

Table 31. Distribution of major- and trace-element concentrations in suspended sediment, lower Columbia River 

Oregon and Washington, 1994—Continued

[Values are reported in micrograms per gram, except aluminum and iron which are in percent; see table 7 for full site names; -- indicates f

samples collected, therefore percentile not calculated; <, less than]

 Site name

Number

of

samples

Minimum

value

Value at indicated percentile Maxim

val

10 25 50 75 90
94

Selenium

 Warrendale 2 0.6 -- -- 0.6 -- -- 0

 Hayden Island 2 .5 -- -- .6 -- -- 

 Columbia City 3 .5 -- -- .6 -- -- 

 Beaver 3 .4 -- -- .6 -- -- 

 Willamette River 3 .3 -- -- .4 -- -- 

Multnomah Channel 3 .4 -- -- .4 -- -- 

 Sandy River 1 .3 -- -- .3 -- -- 

 Cowlitz River 4 <.2 -- -- .4 -- -- 

 All Sites 21 <.2 .3 .4 .4 .6 .6 

Silver

 Warrendale 4 .3 -- -- .3 -- -- 

 Hayden Island 4 .2 -- -- .5 -- -- 

 Columbia City 4 .3 -- -- .4 -- -- 

 Beaver 4 .3 -- -- .5 -- -- 

 Willamette River 4 .3 -- -- .6 -- -- 2

Multnomah Channel 4 .3 -- -- .5 -- -- 

 Sandy River 4 .1 -- -- .3 -- -- 

 Lewis River 3 .1 -- -- .3 -- -- 

 Kalama River 4 .2 -- -- .3 -- -- 

 Cowlitz River 4 <.1 -- -- .1 -- -- 

 All Sites 40 <.1 .1 0.2 .3 .5 .7 2

Zinc

 Warrendale 4 220 -- -- 230 -- -- 300

 Hayden Island 4 190 -- -- 205 -- -- 230

 Columbia City 4 170 -- -- 240 -- -- 260

 Beaver 4 160 -- -- 200 -- -- 270

 Willamette River 4 120 -- -- 145 -- -- 180

Multnomah Channel 4 140 -- -- 175 -- -- 180

 Sandy River 4 81 -- -- 108 -- -- 220

 Lewis River 3 69 -- -- 81 -- -- 95

 Kalama River 4 83 -- -- 106 -- -- 320

 Cowlitz River 4 67 -- -- 79 -- -- 86

 All Sites 40 67 76 88 170 220 259 320

Table 31. Distribution of major- and trace-element concentrations in suspended sediment, lower Columbia River 

Oregon and Washington, 1994—Continued

[Values are reported in micrograms per gram, except aluminum and iron which are in percent; see table 7 for full site names; -- indicates f

samples collected, therefore percentile not calculated; <, less than]

 Site name

Number

of

samples

Minimum

value

Value at indicated percentile Maxim

val

10 25 50 75 90
95

Trace elements transported predominantly in

the filtered-water phase in the lower Columbia

River include arsenic, barium, chromium, and

copper (table 30). Although the filteredwater:suspended ratios for loads always exceeded

one for these elements, they varied with streamflow.

Consider arsenic, which had higher filteredwater:suspended ratios during summer low

streamflows in the lower Columbia River and lower

ratios during spring high streamflows. In the

Columbia River at Warrendale, for example, the

filtered-water:suspended ratios for arsenic for high

and low streamflows, respectively, were 13 and 25.

This same pattern of higher filtered-water loads

during low streamflows in the main stem was

repeated at all main-stem sites and resulted from

low suspended-sediment concentrations, which are

typical of low-streamflow conditions in the main

stem. When suspended-sediment concentrations are

low, the related transport of suspended arsenic is

low and hence the filtered-water:suspended load is

also low.

The dominant transport phase for some

elements alternated from filtered-water to

suspended depending on streamflow conditions. For

example, during winter high flows in the Willamette

River at Portland, the filtered-water zinc phase is

one-fifth the suspended phase. During summer low

streamflows, however, loads shift, and the filteredwater phase is 2.5 times the suspended phase (table

30). These shifts are not attributable to seasonal

variations in concentrations of filtered-water or

suspended zinc; rather, they result from seasonal

variations in suspended-sediment concentration. In

the case of the Willamette River, the suspendedsediment concentration during the November 3,

1994, high-flow sampling was 81 mg/L, whereas it

was only 5 mg/L during the September 13, 1994,

low-flow sampling. These shifts in suspendedsediment concentration have a paramount effect on

suspended-zinc loads. These same effects were not

prominent in the main stem, however. The lack of

shifts in the main stem was probably a result of less

dynamic suspended-sediment concentrations—a

characteristic of the numerous reservoirs in the

main stem which minimize peak streamflow and

result in less resuspension/scouring, and which

provide conditions for settling of particulates in

forebays and their regulating effect on peak

streamflow. Similar transport-phase shifts also were

measured for barium and copper.

The transport dynamics of suspended al

and zinc were studied by computing suspend

over three reaches of the main stem. The sus

loads were determined based on data collect

during a low-streamflow period from August 

September 1994. Aluminum was selected be

its natural abundance, and zinc was selected 

it is a trace contaminant often associated with 

activities. For each reach, the measured load 

downstream site (site-measured load) was co

to the calculated load for the reach (reach-ca

load), and the difference between the two w

computed (table 32). This type of analysis is 

mass balance. The smaller the difference be

the site-measured load and the reach-calculat

the better the mass balance is for the reach. 

comparison, mass-balance calculations also 

made for streamflow, a relatively conservativ

measure. A positive difference between mea

and calculated suspended-zinc loads or strea

implies that unmeasured contributions (from 

nonpoint sources and [or] resuspension and t

of zinc-affected streambed sediment, for exa

the site-measured load exist, whereas a nega

difference implies that unaccountable losses 

suspended-sediment deposition, for example

in the reach. As mentioned earlier, samples th

collected during the low-streamflow months 

used in making intersite-load comparisons w

sometimes separated by days or weeks.

Consequently, variability in daily mean strea

and daily concentrations can contribute to

differences that were observed between sitemeasured and reach-calculated loads.

Between the Columbia River at Warren

(RM 141) and the Columbia River near Colu

City (RM 84), the site-measured zinc load d

from the reach-calculated load by +25 lbs/d. 

difference in load is small (about 3 percent o

site-measured load at Columbia City) and ind

good mass balance over the Warrendale to C

City reach. The major contributing tributary 

this reach is the Willamette River. It has a

suspended-zinc load (39 lbs/d) that is small 

comparison to the 610 lbs/d of suspended-zi

entering the lower Columbia River at Warren

Between Columbia City and the Columbia R

Beaver Army Terminal, the difference betwe

site-measured load and reach-calculated load 

small (+13 lbs/d), and again, is indicative of 
96

Table 32. Mass balances for streamflow, suspended zinc loads, and suspended aluminum loads, lower Columbia River Basin, Orego

through September, 1994

[Loads were determined from instantaneous measurements of suspended aluminum and zinc concentrations made during a low-streamflow period and daily mean strelement sample was collected; ft3/s, cubic feet per second; lb/d, pounds per day; --, not applicable; nd, no data; see table 7 for full site names; see page 95 for a discu

Site name Sampling date Columbia river mile

Streamflow (ft3/s) Suspended zinc load (lb/d) Sus

Main Stem

Tributary

inflowing

Main stem

Tributary

Inflowing

Site

measured

Reach

calculated

Site measured -

Reach calculated

Site

measured

Reach

calculated

Site measured -

Reach calculated

Site

measured

Warrendale 08-10-1994 141 93,800 -- -- -- 610 -- -- -- 65 Sandy River 08-15-1994 120.5 -- -- -- 570 -- -- -- 5.4 -- 

Hayden Island nd 102 nd nd nd -- nd nd nd -- nd Willamette River 09-13-1994 101.5 -- -- -- 9,000 -- -- -- 39 -- 

Lewis River 09-07-1994 87 -- -- -- 1,250 -- -- -- .6 -- 

Columbia City 09-14-1994 84 97,000 104,620 -

7,620

 -- 680 655 +25 -- 89 

Kalama River 08-17-1994 73.1 -- -- -- 200 -- -- -- 1.0 -- 

Cowlitz River 08-31-1994 68 -- -- -- 3,230 -- -- -- 46.4 -- Beaver Army Terminal 08-11-1994 53.8 90,800 100,430 -

9,630

-- 740 727 +13 -- 130 
97

mass balance for suspended zinc. The major

contributing tributary over this reach is the Cowlitz

River, which has a suspended-zinc load (46 lbs/d)

that is slightly larger than that of the Willamette

River but small in comparison to the load at

Warrendale. The difference in load between the

Willamette River and the Cowlitz River results from

a higher concentration of suspended sediment in the

Cowlitz River, rather than a higher concentration of

suspended zinc. The general agreement between site

measured and reach calculated loads (good mass

balance) is indicative of a sampling network that

spatially is adequate to account for major sources of

trace elements in the lower Columbia River Basin.

The good mass balance, however, is limited to lowstreamflow periods in late summer. The degree of

mass balance during high streamflow periods is

unknown. Depending on the magnitude of the high

streamflows, mass balance may be affected by

resuspension and transport between reaches and by

load contributions from episodic point sources.

Organic Compounds

Water samples in the lower Columbia River

Basin were analyzed for organic compounds

beginning in 1965. This limited period of record

and the high cost of analysis explain why the

number of determinations for organic compounds is

much smaller than those for other constituents

addressed in this report. Of the 82 organic

compounds analyzed historically, 32 were not

detected and 56 had fewer than 10 detections (table

33).

Organic compounds were detected at 7 of the

10 sites in 1994; data for sites with detections are

listed in table 34. The organic compounds analyzed,

including common name, application, and pesticide

class are shown in table 35. Of the 47 organic

compounds analyzed, 20 were detected in this

study. Organic compounds were detected at all four

main-stem sites and at three of the six tributary

sites. The Willamette River at Portland had the

largest number of detections, and, of the 20 organic

compounds detected in the lower Columbia River

Basin, all were detected at one time or another in

the Willamette River. Sites without any detections

of organic compounds were the Sandy River near

Troutdale, Kalama River above Spencer Creek near

Kalama, and Cowlitz River at Kelso.

In addition to determinations of the 47 

compounds listed above, a second suite of 41 

compounds was analyzed using a high perfo

liquid chromatography (HPLC) method whic

presently under development by the USGS. 

assurance for this new method is under revie

USGS’s Methods Development Group. The 

reviewing analytical-method performance, is

related to sample preservation and sample

degradation, potential for saturation of the s

phase adsorbent cartridge and subsequent lo

analyte prior to analysis, lapsed time betwee

extraction from the solid-phase cartridge and 

analysis, potential for coelution of analytes, 

other factors that ultimately affect the qualit

reported organic-compound data. Consequen

second suite of organic compounds were una

for use in the current study. Preliminary resu

however, show that only a limited number of 

compounds were detected and that false pos

detections are not a problem with the metho

45 samples analyzed using HPLC in 1994, o

detections were reported in the Willamette R

Columbia River near Beaver Army Terminal

six detections represent five organic compou

dicamba, 2,4-D, diuron, 1-naphthol, and car

Atrazine, a triazine herbicide and the m

frequently detected organic compound in the 

Columbia River Basin, was detected in 23 o

samples (fig. 33). The herbicides metolachlo

simazine, the next most frequently detected 

compounds, were detected in 17 and 16 of 4

samples, respectively. The largest concentra

atrazine, metolachlor, and simazine were me

the Willamette River at Portland. Atrazine

concentrations in the Willamette River, for e

ranged from 0.01 to 0.18 μg/L, and the med

concentration (0.033 μg/L) was more than 1

the median concentrations found at the four 

stem sites (table 36). The atrazine metabolit

deethylatrazine, was detected in 9 of 45 dete

minations, and 8 of the 9 detections were in 

Willamette River and Multnomah Channel. N

the atrazine concentrations measured in the 

Columbia River Basin, however, exceeded th

lifetime health advisory level of 3 μg/L. Add

tionally, none of the organic compounds mea

the lower Columbia River Basin in 1994 exc

EPA’s ambient water-quality criteria or drink

water guidelines (table 49, at back of report)
98

Table 33. Number of historical determinations and uncensored data values for organic compounds, lower Columbia R

Oregon and Washington, 1965-93

[All compounds listed are in filtered water unless otherwise stated; the term “filtered water” is an operational definition referring to the chemical 

portion of a water-suspended sediment sample that passes through a nominal 0.70-micrometer filter; conversely, the term “unfiltered water” refers 

analysis of a water sample that has not been filtered or centrifuged, nor in any way altered from the original matrix; STORET, U.S. Environmenta

Agency’s STOrage and RETrieval system; 2, 4-D, (2,4- dichlorophenoxy) acetic acid; 2,4-DB, 4-(2,4-dichlorophenoxy)butyric acid; DCPA, 3’,4

dichloropropionanilide; DDE, dichlorodiphenyldichloroethylene; EPTC, S-ethyl dipropyl thiocarbamate; HCH, hexachlorocyclohexane; MCPA, 

methylphenoxy) acetic acid; MCPB, 4-(4-chloro-2-methylphenoxy) butyric acid; 2,4,5-T, (2,4,5-trichlorophenoxy) acetic acid; --, not applicable o

STORET

code Compound name Chemical Abstracts Services registry number

Number of historical

determinations

Number of uncensored

data values

49315 Acifluorfen 50594-66-6 231 0

46342 Alachlor 15972-60-8 303 20

49312 Aldicarb 116-06-3 228 0

49313 Aldicarb sulfone 1646-88-4 228 0

49314 Aldicarb sulfoxide -- 228 0

39632 Atrazine 1912-24-9 309 252

39630 Atrazine, unfiltered 1912-24-9 21 9

82686 Azinphos-methyl 86-50-0 284 5

82673 Benfluralin 1861-40-1 288 2

38711 Bentazon 25057-89-0 231 7

04029 Bromacil 314-40-9 247 5

49311 Bromoxynil 1689-84-5 231 2

04028 Butylate 2008-41-5 288 0

49310, 82680 Carbaryl 63-25-2 516 72

49309 Carbofuran 1563-66-2 228 19

49306 Chlorothalonil 1897-45-6 228 0

38933 Chlorpyrifos 2921-88-2 296 94

49305 Clopyralid 1702-17-6 231 0

04041 Cyanazine 21725-46-2 303 1

39732 2,4-D 94-75-7 251 24

39730 2,4-D, unfiltered 94-75-7 62 39

49304 Dacthal 1861-32-1 231 0

38746 2,4-DB 94-82-6 231 0

82682 DCPA 1861-32-1 288 93

34653 p,p’-DDE 72-55-9 288 13

04040 Deethylatrazine 6190-65-4 303 137

39572 Diazinon 333-41-5 298 159

38442 Dicamba 1918-00-9 231 3

49303 Dichlobenil 1194-65-6 228 4

49302 Dichlorprop 120-36-5 231 0

39381 Dieldrin 60-57-1 297 8

82660 2,6-Diethylaniline 91-66-7 288 0

82662 Dimethoate 60-51-5 234 5

49301 Dinoseb 88-85-7 231 8

82677 Disulfoton 298-04-4 288 0

49300 Diuron 330-54-1 228 103

82668 EPTC 759-94-4 288 115

49298 Esfenvalerate 66230-04-4 228 0

82663 Ethalfluralin 55283-68-6 288 0

82672 Ethoprop 13194-48-4 288 77

39762 Fenoprop (silvex) 93-72-1 250 0

49297 Fenuron 101-42-8 228 0

38811 Fluometuron 2164-17-2 228 0

04095 Fonofos 944-22-9 295 68

34253 alpha-HCH 319-84-6 288 0

39341 gamma-HCH (lindane) 58-89-9 297 23
99

49308 3-Hydroxycarbofuran -- 228 0

38478,82666 Linuron 330-55-2 576 1

39532 Malathion 121-75-5 297 27

38482 MCPA 94-74-6 231 2

38487 MCPB 94-81-5 231 0

38501 Methiocarb 2032-65-7 228 2

49296 Methomyl 16752-77-5 228 0

82667 Methyl parathion 298-00-0 288 0

39415 Metolachlor 51218-45-2 303 215

82630 Metribuzin 21087-64-9 303 60

82671 Molinate 2212-67-1 288 0

49295 1-Naphthol -- 228 1

82684 Napropamide 15299-99-7 288 104

49294 Neburon 555-37-3 228 0

49293 Norflurazon 27314-13-2 228 0

49292 Oryzalin 19044-88-3 228 3

38866 Oxamyl 23135-22-0 228 1

39542 Parathion 56-38-2 297 0

82669 Pebulate 1114-71-2 288 1

82683 Pendimethalin 40487-42-1 288 12

82687 cis-Permethrin 52645-53-1 288 2

82664 Phorate 298-02-2 288 0

49291 Picloram 1918-02-1 231 0

04037 Prometon 1610-18-0 303 56

82676 Pronamide 23950-58-5 289 35

04024 Propachlor 1918-16-7 288 11

82679 Propanil 709-98-8 288 5

82685 Propargite 2312-35-8 288 3

49236 Propham 122-42-9 228 0

38538 Propoxur 114-26-1 226 0

04035 Simazine 122-34-9 309 220

39742 2,4,5-T 93-76-5 252 2

39740 2,4,5-T, unfiltered 93-76-5 59 17

82670 Tebuthiuron 34014-18-1 288 42

82665 Terbacil 5902-51-2 284 59

82675 Terbufos 13071-79-9 288 0

82681 Thiobencarb 28249-77-6 288 0

79747 Total organic halide -- 92 76

82678 Triallate 2303-17-5 288 7

49235 Triclopyr 55335-06-3 231 16

82661 Trifluralin 1582-09-8 288 42

Table 33. Number of historical determinations and uncensored data values for organic compounds, lower Columbia R

Oregon and Washington, 1965-93—Continued

[All compounds listed are in filtered water unless otherwise stated; the term “filtered water” is an operational definition referring to the chemical 

portion of a water-suspended sediment sample that passes through a nominal 0.70-micrometer filter; conversely, the term “unfiltered water” refers 

analysis of a water sample that has not been filtered or centrifuged, nor in any way altered from the original matrix; STORET, U.S. Environmenta

Agency’s STOrage and RETrieval system; 2, 4-D, (2,4- dichlorophenoxy) acetic acid; 2,4-DB, 4-(2,4-dichlorophenoxy)butyric acid; DCPA, 3’,4

dichloropropionanilide; DDE, dichlorodiphenyldichloroethylene; EPTC, S-ethyl dipropyl thiocarbamate; HCH, hexachlorocyclohexane; MCPA, 

methylphenoxy) acetic acid; MCPB, 4-(4-chloro-2-methylphenoxy) butyric acid; 2,4,5-T, (2,4,5-trichlorophenoxy) acetic acid; --, not applicable o

STORET

code Compound name Chemical Abstracts Services registry number

Number of historical

determinations

Number of uncensored

data values
100

Table 34. Concentrations of organic compounds detected in filtered water, lower Columbia River Basin, Ore

Washington, 1994

[Only detectable concentrations are listed in this table; the term “filtered water” is an operational definition referring to the chemical

analysis of that portion of a water-suspended sediment sample that passes through a nominal 0.70-micrometer filter; E, estimated val

Site name Date Concentration

Alachlor

Willamette River at Portland, Oregon 12-02-1994 0.002 E

Atrazine

Columbia River at Warrendale, Oregon 08-10-1994 .002

Columbia River at Warrendale, Oregon 11-08-1994 .006 E

Columbia River, river mile 102, downstream of Hayden Island, Oregon 03-22-1994 .003

Columbia River, river mile 102, downstream of Hayden Island, Oregon 07-25-1994 .003

Columbia River, river mile 102, downstream of Hayden Island, Oregon 12-05-1994 .003 E

Columbia River near Columbia City, Oregon 07-26-1994 .004

Columbia River near Columbia City, Oregon 11-09-1994 .020

Columbia River at Beaver Army Terminal near Quincy, Oregon 04-14-1994 .032

Columbia River at Beaver Army Terminal near Quincy, Oregon 08-11-1994 .004

Willamette River at Portland, Oregon 02-25-1994 .160

Willamette River at Portland, Oregon 03-14-1994 .037

Willamette River at Portland, Oregon 04-11-1994 .170

Willamette River at Portland, Oregon 05-10-1994 .020

Willamette River at Portland, Oregon 06-14-1994 .012

Willamette River at Portland, Oregon 08-08-1994 .010

Willamette River at Portland, Oregon 09-13-1994 .013 E

Willamette River at Portland, Oregon 10-29-1994 .029

Willamette River at Portland, Oregon 11-03-1994 .130

Willamette River at Portland, Oregon 12-02-1994 .180

Multnomah Channel near mouth, at St. Helens, Oregon 06-10-1994 .011

Multnomah Channel near mouth, at St. Helens, Oregon 08-09-1994 .008

Multnomah Channel near mouth, at St. Helens, Oregon 12-07-1994 .160

Lewis River at Woodland, Washington 06-29-1994 .003

Carbaryl

Willamette River at Portland, Oregon 02-25-1994 .017

Willamette River at Portland, Oregon 10-29-1994 .006 E

Carbofuran

Willamette River at Portland, Oregon 10-29-1994 .180 E

Willamette River at Portland, Oregon 11-03-1994 .088 E

Chlorpyrifos

Willamette River at Portland, Oregon 12-02-1994 .006

Lewis River at Woodland, Washington 07-19-1994 .010
101

Dacthal; Chlorthal-dimethyl (DCPA)

Columbia River at Warrendale, Oregon 06-15-1994 0.001

Columbia River at Warrendale, Oregon 11-08-1994 .003 E

Columbia River, river mile 102, downstream of Hayden Island, Oregon 12-05-1994 .001 E

Columbia River near Columbia City, Oregon 11-09-1994 .003 E

Columbia River at Beaver Army Terminal near Quincy, Oregon 08-11-1994 .002

Willamette River at Portland, Oregon 10-29-1994 .004

Willamette River at Portland, Oregon 12-02-1994 .001 E

Deethylatrazine

Columbia River at Beaver Army Terminal near Quincy, Oregon 04-14-1994 .003

Willamette River at Portland, Oregon 02-25-1994 .026

Willamette River at Portland, Oregon 04-11-1994 .010

Willamette River at Portland, Oregon 05-10-1994 .005

Willamette River at Portland, Oregon 10-29-1994 .004 E

Willamette River at Portland, Oregon 11-03-1994 .004 E

Willamette River at Portland, Oregon 12-02-1994 .006 E

Multnomah Channel near mouth, at St. Helens, Oregon 06-10-1994 .006

Multnomah Channel near mouth, at St. Helens, Oregon 12-07-1994 .009 E

Diazinon

Willamette River at Portland, Oregon 05-10-1994 .006

Willamette River at Portland, Oregon 06-14-1994 .009

Willamette River at Portland, Oregon 08-08-1994 .007

Willamette River at Portland, Oregon 09-13-1994 .008 E

Willamette River at Portland, Oregon 10-29-1994 .006 E

Multnomah Channel near mouth, at St. Helens, Oregon 06-10-1994 .006

Multnomah Channel near mouth, at St. Helens, Oregon 08-09-1994 .005

Eptam (EPTC)

Columbia River at Warrendale, Oregon 05-11-1994 .006

Columbia River at Warrendale, Oregon 06-15-1994 .003

Columbia River, river mile 102, downstream of Hayden Island, Oregon 03-22-1994 .002

Columbia River, river mile 102, downstream of Hayden Island, Oregon 05-25-1994 .004

Columbia River near Columbia City, Oregon 05-09-1994 .005

Willamette River at Portland, Oregon 05-10-1994 .005

Willamette River at Portland, Oregon 06-14-1994 .005

Willamette River at Portland, Oregon 12-02-1994 .004 E

Multnomah Channel near mouth, at St. Helens, Oregon 06-10-1994 .006

Table 34. Concentrations of organic compounds detected in filtered water, lower Columbia River Basin, Ore

Washington, 1994—Continued

[Only detectable concentrations are listed in this table; the term “filtered water” is an operational definition referring to the chemical

analysis of that portion of a water-suspended sediment sample that passes through a nominal 0.70-micrometer filter; E, estimated val

Site name Date Concentration
102

Ethoprop

Willamette River at Portland, Oregon 10-29-1994 0.015

Willamette River at Portland, Oregon 11-03-1994 .023

Willamette River at Portland, Oregon 12-02-1994 .005 E

Fonofos

Willamette River at Portland, Oregon 04-11-1994 .010

Willamette River at Portland, Oregon 10-25-1994 .002 E

Willamette River at Portland, Oregon 11-03-1994 .005 E

Willamette River at Portland, Oregon 12-02-1994 .005 E

Metolachlor

Columbia River at Warrendale, Oregon 11-08-1994 .004 E

Columbia River, river mile 102, downstream of Hayden Island, Oregon 12-05-1994 .002 E

Columbia River near Columbia City, Oregon 11-09-1994 .017

Columbia River at Beaver Army Terminal near Quincy, Oregon 04-14-1994 .002

Columbia River at Beaver Army Terminal near Quincy, Oregon 08-11-1994 .003

Willamette River at Portland, Oregon 02-25-1994 .016

Willamette River at Portland, Oregon 03-14-1994 .006

Willamette River at Portland, Oregon 04-11-1994 .008

Willamette River at Portland, Oregon 05-10-1994 .005

Willamette River at Portland, Oregon 06-14-1994 .004

Willamette River at Portland, Oregon 09-13-1994 .003 E

Willamette River at Portland, Oregon 10-29-1994 .049

Willamette River at Portland, Oregon 11-03-1994 .110

Willamette River at Portland, Oregon 12-02-1994 .048

Multnomah Channel near mouth, at St. Helens, Oregon 06-10-1994 .004

Multnomah Channel near mouth, at St. Helens, Oregon 10-26-1994 .008 E

Multnomah Channel near mouth, at St. Helens, Oregon 12-07-1994 .044

Metribuzin

Willamette River at Portland, Oregon 02-25-1994 .029

Willamette River at Portland, Oregon 12-02-1994 .020

Multnomah Channel near mouth, at St. Helens, Oregon 12-07-1994 .021

Napropamide

Columbia River, river mile 102, downstream of Hayden Island, Oregon 12-05-1994 .007 E

Willamette River at Portland, Oregon 02-25-1994 .068

Willamette River at Portland, Oregon 10-29-1994 .022

Willamette River at Portland, Oregon 11-03-1994 .029

Willamette River at Portland, Oregon 12-02-1994 .006 E

Table 34. Concentrations of organic compounds detected in filtered water, lower Columbia River Basin, Ore

Washington, 1994—Continued

[Only detectable concentrations are listed in this table; the term “filtered water” is an operational definition referring to the chemical

analysis of that portion of a water-suspended sediment sample that passes through a nominal 0.70-micrometer filter; E, estimated val

Site name Date Concentration
103

Prometon

Willamette River at Portland, Oregon 08-08-1994 0.003

Pronamide

Willamette River at Portland, Oregon 02-25-1994 .030

Willamette River at Portland, Oregon 12-02-1994 .018

Simazine

Columbia River at Warrendale, Oregon 08-10-1994 .001

Columbia River near Columbia City, Oregon 11-09-1994 .009

Columbia River at Beaver Army Terminal near Quincy, Oregon 04-14-1994 .011

Willamette River at Portland, Oregon 02-25-1994 .064

Willamette River at Portland, Oregon 03-14-1994 .013

Willamette River at Portland, Oregon 04-11-1994 .049

Willamette River at Portland, Oregon 05-10-1994 .010

Willamette River at Portland, Oregon 06-14-1994 .016

Willamette River at Portland, Oregon 08-08-1994 .005

Willamette River at Portland, Oregon 09-13-1994 .008

Willamette River at Portland, Oregon 10-29-1994 .066

Willamette River at Portland, Oregon 11-03-1994 .073

Willamette River at Portland, Oregon 12-02-1994 .043

Multnomah Channel near mouth, at St. Helens, Oregon 06-10-1994 .019

Multnomah Channel near mouth, at St. Helens, Oregon 08-09-1994 .004

Multnomah Channel near mouth, at St. Helens, Oregon 12-07-1994 .035

Tebuthiuron

Willamette River at Portland, Oregon 02-25-1994 .006

Willamette River at Portland, Oregon 10-29-1994 .007 E

Willamette River at Portland, Oregon 12-02-1994 .003 E

Terbacil

Willamette River at Portland, Oregon 02-25-1994 .032

Willamette River at Portland, Oregon 04-11-1994 .080

Willamette River at Portland, Oregon 10-29-1994 .017 E

Willamette River at Portland, Oregon 11-03-1994 .027 E

Willamette River at Portland, Oregon 12-02-1994 .010 E

Multnomah Channel near mouth, at St. Helens, Oregon 06-10-1994 .012

Multnomah Channel near mouth, at St. Helens, Oregon 12-07-1994 .008 E

Triallate

Willamette River at Portland, Oregon 02-25-1994 .004

Willamette River at Portland, Oregon 12-02-1994 .008 E

Table 34. Concentrations of organic compounds detected in filtered water, lower Columbia River Basin, Ore

Washington, 1994—Continued

[Only detectable concentrations are listed in this table; the term “filtered water” is an operational definition referring to the chemical

analysis of that portion of a water-suspended sediment sample that passes through a nominal 0.70-micrometer filter; E, estimated val

Site name Date Concentration
104

Table 35. Chemical classifications for organic compounds analyzed, lower Columbia River Basin, Oregon 

Washington, 1994

[--, no trade name; *, metabolite or pesticide no longer registered for use; see table 9 for Chemical Abstracts Services registry numb

Common Name Trade name Application Class

acetochlor Acenit; Elbacet; Harness; Mon-097 herbicide chloroacetamide

alachlor Lasso herbicide chloroacetamide

atrazine AAtrex herbicide triazine

azinphos-methyl Guthion insecticide organophosphate

benfluralin Benefin; Balan; Bonalan herbicide dinitroaniline

butylate Genate plus; Suntan + herbicide dinitroaniline

carbaryl Sevin insecticide carbamate

carbofuran Furandan insecticide carbamate

chlorpyrifos Dursban insecticide organophosphate

cyanazine -- herbicide triazine

DCPA Dacthal; Chlorthal-dimethyl herbicide organochlorine

4,4’-DDE -- insecticide organochlorine

deethylatrazine -- * metabolite

diazinon -- insecticide organophosphate

dieldrin Panoram D-31 insecticide organochlorine

2,6-diethylaniline -- * metabolite

disulfoton -- insecticide organophosphate

EPTC Eptam herbicide carbamate

ethalfluralin Sonalan herbicide dinitroaniline

ethoprop Mocap; Ethoprophos insecticide organophosphate

fonofos Dyfonate insecticide organophosphate

alpha-HCH alpha-BHC insecticide organochlorine

gamma-HCH Lindane insecticide organochlorine

linuron Lorox; Linex herbicide phenyl urea

malathion -- insecticide organophosphate

metolachlor Dual herbicide chloroacetamide

methyl parathion Denncap-M insecticide organophosphate

metribuzin Lexone; Sencor herbicide triazine

molinate Ordram herbicide carbamate

napropamide Devrinol herbicide chloroacetamide

parathion -- insecticide organophosphate

pebulate Tillam herbicide carbamate

pendimethilan Prowl; Stomp herbicide dinitroaniline

cis-permethrin Pounce; Ambush insecticide permethrin

phorate Thimet insecticide organophosphate

prometon Pramitol herbicide triazine

pronamide Kerb, Propyzamid herbicide chloroacetamide

propachlor Ramrod herbicide chloroacetamide

propanil Stampede herbicide chloroacetamide

propargite Omite, Alkyl sulfite insecticide miscellaneous

simazine Aquazine, Princep herbicide triazine

tebuthiuron Spike herbicide phenyl urea

terbacil Sinbar herbicide uracil

terbufos Counter insecticide organophosphate

thiobencarb Bolero herbicide carbamate

triallate Avadex bw, Far-go herbicide carbamate

trifluralin Treflan herbicide dinitroaniline
105

Atrazine, metolachlor, and simazine, were

detected in 93, 86, and 93 percent, respectively, of

the samples collected in the Willamette River and

Multnomah Channel (fig. 34). Additionally, all of

the frequently detected pesticides shown in figure

33—except for DCPA—were detected more often in

the Willamette River and Multnomah Channel, than

at the other main-stem and tributary sites in the

lower Columbia River Basin. The high percentage

of detections of agricultural organic compounds

from the Willamette River Basin reflects the fact

that most of the lower Columbia River Basin’s

agricultural land is in the Willamette Basin (table

2).

Although not detected as frequently as the

before-mentioned organic compounds, EPTC

(eptam6) was detected in the lower Columbia River

Basin shortly after the spring-application period. It

was detected consistently from March to June 1994

in concentrations ranging from 0.002 to 0.006 μg/L

in the main stem at Warrendale, Hayden Island, and

Columbia City, and in the Willamette River and

6

EPTC, a selective carbamate herbicide that decomposes in 4

to 6 weeks, has been used as a preplant soil treatment to inhibit the

growth of weed seedlings (Burrill and others, 1992). ATRAZINE METOLACHLOR SIMAZINE DEETHYLATRAZINE EPTC TERBACIL DCPA DIAZINON

NAPROPAMIDE

ORGANIC COMPOUND

0

25

5

10

15

20

NUMBER OF DETECTIONS

Figure 33. Frequently detected organic compounds, lower

Columbia River Basin, Oregon and Washington,

1994. (Numbers are based on total of 45 samples.)

Multnomah Channel tributaries. EPTC was

introduced in the lower Columbia River Bas

early 1960s and is used to treat a variety of 

including beans, peas, sugar-beet root, clove

strawberries. It was used through the time of 

study (John Rinehold, Oregon State Univers

commun., 1994).

The Willamette River, which is a sourc

atrazine to the lower Columbia River, has hi

atrazine concentrations during the spring an

high-streamflow periods than during the sum

low-streamflow period (fig. 35). High atrazin

concentrations associated with spring runoff

coincide with periods of application. Atrazin

used for preemergent-weed control in prepar

for grain crops and nursery stock and is norm

applied in March and April when soil moistu

high and before winter rains cease (Burrill a

others, 1992). In the Willamette River Basin 

382,000 lbs of atrazine were applied in 1987

contrast, only 4,500 lbs were applied in the

Clatskanie River drainage (John Rinehold, O

State University, unpub. data, 1993). The hig

atrazine concentrations measured in Novemb

December coincide with high suspended-sed

concentrations. These higher atrazine concen

probably result from the presence of soil-sor

atrazine that was flushed from freshly erode

agricultural soils that enter the stream durin

runoff.

Most likely, however, these higher

concentrations during fall runoff were not

transported in the suspended phase. Instead,

equilibrium calculations show that atrazine i

Willamette River at Portland, during fall and 

runoff, is predominantly in the filtered-wate

(dissolved) phase. Using a suspended organi

carbon-water sorption coefficient (Koc) of 16

(Mercer and others, 1990), and data from th

November 3, 1994 sampling in the Willamett

the fraction of atrazine transported in the su

form can be calculated from the following eq

The Koc is related to the sorption coefficient 

Koc = Kd /foc 

where foc is the organic carbon fraction in th

suspended sediment and Kd is defined as
106

Table 36. Distribution of organic-compound concentrations in filtered water, lower Columbia River Basin, Orego

Washington, 1994

[The term “filtered water” is an operational definition referring to the chemical analysis of that portion of a water-suspended sediment sam

through a nominal 0.70-micrometer filter; to avoid statistical bias that may be associated with constituents analyzed more than once at a s

element concentration per month was statistically summarized; concentrations are reported in micrograms per liter; acetochlor, azinphos-

benfluralin, butylate, cyanazine, 4,4’-DDE, dieldrin, 2,6-diethylaniline, dimethoate, disulfoton, ethalfluralin, alpha-HCH, gamma-HCH (lin

malathion, methyl parathion, molinate, parathion, pebulate, pendimethalin, cis-permethrin, phorate, propachlor, propanil, propargite, tebu

terbufos, thiobencarb, and trifluralin are not included in this table, because no samples had concentrations greater than their correspondin

detection limit; see table 9 for Chemical Abstracts Services registry numbers and method detection limits; see table 7 for full site names; -- 

than 6 samples were collected, therefore the percentile was not calculated; <, less than]

 Site name

Number

of

samples

Minimum

value

Value at indicated percentile Maxim

valu

10 25 50 75 90

Alachlor

 Warrendale 4 <0.002 -- -- <0.002 -- -- <0.0

 Hayden Island 4 <.002 -- -- <.002 -- -- <.00

 Columbia City 4 <.002 -- -- <.002 -- -- <.00

 Beaver 4 <.002 -- -- <.002 -- -- <.00

 Willamette River 10 <.002 <.002 <.002 <.002 <.002 <.002 .00

Multnomah Channel 4 <.002 -- -- <.002 -- -- <.00

 Sandy River 3 <.002 -- -- <.002 -- -- <.00

 Lewis River 4 <.002 -- -- <.002 -- -- <.00

 Kalama River 4 <.002 -- -- <.002 -- -- <.00

 Cowlitz River 4 <.002 -- -- <.002 -- -- <.00

 All sites 45 <.002 <.002 <.002 <.002 <.002 <.002 .002

Atrazine

 Warrendale 4 <.001 -- -- .001 -- -- .006

 Hayden Island 4 <.001 -- -- .003 -- -- .003

 Columbia City 4 <.001 -- -- .002 -- -- .020

 Beaver 4 <.001 -- -- .002 -- -- .032

 Willamette River 10 .010 .010 .013 .033 .162 .179 .180

Multnomah Channel 4 <.001 -- -- .010 -- -- .160

 Sandy River 3 <.001 -- -- <.001 -- -- <.00

 Lewis River 4 <.001 -- -- <.001 -- -- .00

 Kalama River 4 <.001 -- -- <.001 -- -- <.00

 Cowlitz River 4 <.001 -- -- <.001 -- -- <.00

 All sites 45 <.001 <.001 <.001 .002 .012 .142 .180

Carbaryl

 Warrendale 4 <.003 -- -- <.003 -- -- <.00

 Hayden Island 4 <.003 -- -- <.003 -- -- <.00

 Columbia City 4 <.003 -- -- <.003 -- -- <.00

 Beaver 4 <.003 -- -- <.003 -- -- <.00

 Willamette River 10 <.003 <.003 <.003 <.003 <.003 .016 0.01

Multnomah Channel 4 <.003 -- -- <.003 -- -- <.00

 Sandy River 3 <.003 -- -- <.003 -- -- <.00
107

Carbaryl—Continued

 Lewis River 4 <0.003 -- -- <0.003 -- -- <0.00

 Kalama River 4 <.003 -- -- <.003 -- -- <.00

 Cowlitz River 4 <.003 -- -- <.003 -- -- <.00

 All sites 45 <.003 <0.003 <0.003 <.003 <0.003 <0.003 .01

Carbofuran

 Warrendale 4 <.003 -- -- <.003 -- -- <.00

 Hayden Island 4 <.003 -- -- <.003 -- -- <.00

 Columbia City 4 <.003 -- -- <.003 -- -- <.00

 Beaver 4 <.003 -- -- <.003 -- -- <.00

 Willamette River 10 <.003 <.003 <.003 <.003 .023 .171 .18

Multnomah Channel 4 <.003 -- -- <.003 -- -- <.00

 Sandy River 3 <.003 -- -- <.003 -- -- <.00

 Lewis River 4 <.003 -- -- <.003 -- -- <.00

 Kalama River 4 <.003 -- -- <.003 -- -- <.00

 Cowlitz River 4 <.003 -- -- <.003 -- -- <.00

 All sites 45 <.003 <.003 <.003 <.003 <.003 <.003 .18

Chlorpyrifos

 Warrendale 4 <.004 -- -- <.004 -- -- <.00

 Hayden Island 4 <.004 -- -- <.004 -- -- <.00

 Columbia City 4 <.004 -- -- <.004 -- -- <.00

 Beaver 4 <.004 -- -- <.004 -- -- <.00

 Willamette River 10 <.004 <.004 <.004 <.004 <.004 .006 .00

Multnomah Channel 4 <.004 -- -- <.004 -- -- <.00

 Sandy River 3 <.004 -- -- <.004 -- -- <.00

 Lewis River 4 <.004 -- -- <.004 -- -- .01

 Kalama River 4 <.004 -- -- <.004 -- -- <.00

 Cowlitz River 4 <.004 -- -- <.004 -- -- <.00

 All sites 45 <.004 <.004 <.004 <.004 <.004 <.004 .01

Dacthal; Chlorthal-dimethyl (DCPA)

 Warrendale 4 <.002 -- -- <.002 -- -- .00

 Hayden Island 4 <.002 -- -- <.002 -- -- <.00

 Columbia City 4 <.002 -- -- <.002 -- -- .00

 Beaver 4 <.002 -- -- <.002 -- -- .00

Table 36. Distribution of organic-compound concentrations in filtered water, lower Columbia River Basin, Orego

Washington, 1994—Continued

[The term “filtered water” is an operational definition referring to the chemical analysis of that portion of a water-suspended sediment sam

through a nominal 0.70-micrometer filter; to avoid statistical bias that may be associated with constituents analyzed more than once at a s

element concentration per month was statistically summarized; concentrations are reported in micrograms per liter; acetochlor, azinphos-

benfluralin, butylate, cyanazine, 4,4’-DDE, dieldrin, 2,6-diethylaniline, dimethoate, disulfoton, ethalfluralin, alpha-HCH, gamma-HCH (lin

malathion, methyl parathion, molinate, parathion, pebulate, pendimethalin, cis-permethrin, phorate, propachlor, propanil, propargite, tebu

terbufos, thiobencarb, and trifluralin are not included in this table, because no samples had concentrations greater than their correspondin

detection limit; see table 9 for Chemical Abstracts Services registry numbers and method detection limits; see table 7 for full site names; -- 

than 6 samples were collected, therefore the percentile was not calculated; <, less than]

 Site name

Number

of

samples

Minimum

value

Value at indicated percentile Maxim

valu

10 25 50 75 90
108

Dacthal; Chlorthal-dimethyl (DCPA)—Continued

 Willamette River 10 <0.002 <0.002 <0.002 <0.002 <0.002 0.004 0.00

Multnomah Channel 4 <.002 -- -- <.002 -- -- <.00

 Sandy River 3 <.002 -- -- <.002 -- -- <.00

 Lewis River 4 <.002 -- -- <.002 -- -- <.00

 Kalama River 4 <.002 -- -- <.002 -- -- <.00

 Cowlitz River 4 <.002 -- -- <.002 -- -- <.00

 All sites 45 <.002 <.002 <.002 <.002 <.002 <.002 .00

Deethylatrazine

 Warrendale 4 <.002 -- -- <.002 -- -- <.00

 Hayden Island 4 <.002 -- -- <.002 -- -- <.00

 Columbia City 4 <.002 -- -- <.002 -- -- <.00

 Beaver 4 <.002 -- -- <.002 -- -- .00

 Willamette River 10 <.002 <.002 <.002 .004 .007 .024 .02

Multnomah Channel 4 <.002 -- -- .004 -- -- .00

 Sandy River 3 <.002 -- -- <.002 -- -- <.00

 Lewis River 4 <.002 -- -- <.002 -- -- <.00

 Kalama River 4 <.002 -- -- <.002 -- -- <.00

 Cowlitz River 4 <.002 -- -- <.002 -- -- <.00

 All sites 45 <.002 <.002 <.002 <.002 <.002 .006 .02

Diazinon

 Warrendale 4 <.002 -- -- <.002 -- -- <.00

 Hayden Island 4 <.002 -- -- <.002 -- -- <.00

 Columbia City 4 <.002 -- -- <.002 -- -- <.00

 Beaver 4 <.002 -- -- <.002 -- -- <.00

 Willamette River 10 <.002 <.002 <.002 .004 .007 .009 .00

Multnomah Channel 4 <.002 -- -- .003 -- -- .00

 Sandy River 3 <.002 -- -- <.002 -- -- <.00

 Lewis River 4 <.002 -- -- <.002 -- -- <.00

 Kalama River 4 <.002 -- -- <.002 -- -- <.00

 Cowlitz River 4 <.002 -- -- <.002 -- -- <.00

 All sites 45 <.002 <.002 <.002 <.002 <.002 .006 .00

Eptam (EPTC)

 Warrendale 4 <.002 -- -- .002 -- -- .00

Table 36. Distribution of organic-compound concentrations in filtered water, lower Columbia River Basin, Orego

Washington, 1994—Continued

[The term “filtered water” is an operational definition referring to the chemical analysis of that portion of a water-suspended sediment sam

through a nominal 0.70-micrometer filter; to avoid statistical bias that may be associated with constituents analyzed more than once at a s

element concentration per month was statistically summarized; concentrations are reported in micrograms per liter; acetochlor, azinphos-

benfluralin, butylate, cyanazine, 4,4’-DDE, dieldrin, 2,6-diethylaniline, dimethoate, disulfoton, ethalfluralin, alpha-HCH, gamma-HCH (lin

malathion, methyl parathion, molinate, parathion, pebulate, pendimethalin, cis-permethrin, phorate, propachlor, propanil, propargite, tebu

terbufos, thiobencarb, and trifluralin are not included in this table, because no samples had concentrations greater than their correspondin

detection limit; see table 9 for Chemical Abstracts Services registry numbers and method detection limits; see table 7 for full site names; -- 

than 6 samples were collected, therefore the percentile was not calculated; <, less than]

 Site name

Number

of

samples

Minimum

value

Value at indicated percentile Maxim

valu

10 25 50 75 90
109

Eptam (EPTC)—Continued

 Hayden Island 4 <0.002 -- -- <0.002 -- -- 0.00

 Columbia City 4 <.002 -- -- <.002 -- -- .00

 Beaver 4 <.002 -- -- <.002 -- -- <.00

 Willamette River 10 <.002 <.002 <.002 <.002 0.004 0.005 .00

Multnomah Channel 4 <.002 -- -- <.002 -- -- .00

 Sandy River 3 <.002 -- -- <.002 -- -- <.00

 Lewis River 4 <.002 -- -- <.002 -- -- <.00

 Kalama River 4 <.002 -- -- <.002 -- -- <.00

 Cowlitz River 4 <.002 -- -- <.002 -- -- <.00

 All sites 45 <.002 <.002 <.002 <.002 <.002 .005 .00

Ethoprop

 Warrendale 4 <.003 -- -- <.003 -- -- <.00

 Hayden Island 4 <.003 -- -- <.003 -- -- <.00

 Columbia City 4 <.003 -- -- <.003 -- -- <.00

 Beaver 4 <.003 -- -- <.003 -- -- <.00

 Willamette River 10 <.003 <.003 <.003 <.003 .008 .022 .02

Multnomah Channel 4 <.003 -- -- <.003 -- -- <.00

 Sandy River 3 <.003 -- -- <.003 -- -- <.00

 Lewis River 4 <.003 -- -- <.003 -- -- <.00

 Kalama River 4 <.003 -- -- <.003 -- -- <.00

 Cowlitz River 4 <.003 -- -- <.003 -- -- <.00

 All sites 45 <.003 <.003 <.003 <.003 <.003 <.003 .02

Fonofos

 Warrendale 4 <.003 -- -- <.003 -- -- <.00

 Hayden Island 4 <.003 -- -- <.003 -- -- <.00

 Columbia City 4 <.003 -- -- <.003 -- -- <.00

 Beaver 4 <.003 -- -- <.003 -- -- <.00

 Willamette River 10 <.003 <.003 <.003 <.003 .005 .010 .01

Multnomah Channel 4 <.003 -- -- <.003 -- -- <.00

 Sandy River 3 <.003 -- -- <.003 -- -- <.00

 Lewis River 4 <.003 -- -- <.003 -- -- <.00

 Kalama River 4 <.003 -- -- <.003 -- -- <.00

 Cowlitz River 4 <.003 -- -- <.003 -- -- <.00

 All sites 45 <.003 <.003 <.003 <.003 <.003 <.003 00.01

Table 36. Distribution of organic-compound concentrations in filtered water, lower Columbia River Basin, Orego

Washington, 1994—Continued

[The term “filtered water” is an operational definition referring to the chemical analysis of that portion of a water-suspended sediment sam

through a nominal 0.70-micrometer filter; to avoid statistical bias that may be associated with constituents analyzed more than once at a s

element concentration per month was statistically summarized; concentrations are reported in micrograms per liter; acetochlor, azinphos-

benfluralin, butylate, cyanazine, 4,4’-DDE, dieldrin, 2,6-diethylaniline, dimethoate, disulfoton, ethalfluralin, alpha-HCH, gamma-HCH (lin

malathion, methyl parathion, molinate, parathion, pebulate, pendimethalin, cis-permethrin, phorate, propachlor, propanil, propargite, tebu

terbufos, thiobencarb, and trifluralin are not included in this table, because no samples had concentrations greater than their correspondin

detection limit; see table 9 for Chemical Abstracts Services registry numbers and method detection limits; see table 7 for full site names; -- 

than 6 samples were collected, therefore the percentile was not calculated; <, less than]

 Site name

Number

of

samples

Minimum

value

Value at indicated percentile Maxim

valu

10 25 50 75 90
110

Metolachlor

 Warrendale 4 <0.002 -- -- <0.002 -- -- 0.00

 Hayden Island 4 <.002 -- -- <.002 -- -- .00

 Columbia City 4 <.002 -- -- <.002 -- -- .01

 Beaver 4 <.002 -- -- <.002 -- -- .00

 Willamette River 10 <.002 <0.002 0.004 .007 0.048 0.104 .11

Multnomah Channel 4 <.002 -- -- .006 -- -- .04

 Sandy River 3 <.002 -- -- <.002 -- -- <.00

 Lewis River 4 <.002 -- -- <.002 -- -- <.00

 Kalama River 4 <.002 -- -- <.002 -- -- <.00

 Cowlitz River 4 <.002 -- -- <.002 -- -- <.00

 All sites 45 <.002 <.002 <.002 <.002 .004 .028 .11

Metribuzin

 Warrendale 4 <.004 -- -- <.004 -- -- <.00

 Hayden Island 4 <.004 -- -- <.004 -- -- <.00

 Columbia City 4 <.004 -- -- <.004 -- -- <.00

 Beaver 4 <.004 -- -- <.004 -- -- <.00

 Willamette River 10 <.004 <.004 <.004 <.004 .006 .028 .02

Multnomah Channel 4 <.004 -- -- <.004 -- -- .02

 Sandy River 3 <.004 -- -- <.004 -- -- <.00

 Lewis River 4 <.004 -- -- <.004 -- -- <.00

 Kalama River 4 <.004 -- -- <.004 -- -- <.00

 Cowlitz River 4 <.004 -- -- <.004 -- -- <.00

 All sites 45 <.004 <.004 <.004 <.004 <.004 <.004 .02

Napropamide

 Warrendale 4 <.003 -- -- <.003 -- -- <.00

 Hayden Island 4 <.003 -- -- <.003 -- -- .00

 Columbia City 4 <.003 -- -- <.003 -- -- <.00

 Beaver 4 <.003 -- -- <.003 -- -- <.00

 Willamette River 10 <.003 <.003 <.003 <.003 .024 .064 .06

Multnomah Channel 4 <.003 -- -- <.003 -- -- <.00

 Sandy River 3 <.003 -- -- <.003 -- -- <.00

Table 36. Distribution of organic-compound concentrations in filtered water, lower Columbia River Basin, Orego

Washington, 1994—Continued

[The term “filtered water” is an operational definition referring to the chemical analysis of that portion of a water-suspended sediment sam

through a nominal 0.70-micrometer filter; to avoid statistical bias that may be associated with constituents analyzed more than once at a s

element concentration per month was statistically summarized; concentrations are reported in micrograms per liter; acetochlor, azinphos-

benfluralin, butylate, cyanazine, 4,4’-DDE, dieldrin, 2,6-diethylaniline, dimethoate, disulfoton, ethalfluralin, alpha-HCH, gamma-HCH (lin

malathion, methyl parathion, molinate, parathion, pebulate, pendimethalin, cis-permethrin, phorate, propachlor, propanil, propargite, tebu

terbufos, thiobencarb, and trifluralin are not included in this table, because no samples had concentrations greater than their correspondin

detection limit; see table 9 for Chemical Abstracts Services registry numbers and method detection limits; see table 7 for full site names; -- 

than 6 samples were collected, therefore the percentile was not calculated; <, less than]

 Site name

Number

of

samples

Minimum

value

Value at indicated percentile Maxim

valu

10 25 50 75 90
111

Napropamide—Continued

 Lewis River 4 <0.003 -- -- <0.003 -- -- <0.00

 Kalama River 4 <.003 -- -- <.003 -- -- <.00

 Cowlitz River 4 <.003 -- -- <.003 -- -- <.00

 All sites 45 <.003 <0.003 <0.003 <.003 <0.003 0.006 .06

Prometon

 Warrendale 4 <.003 -- -- <.003 -- -- <.00

 Hayden Island 4 <.003 -- -- <.003 -- -- <.00

 Columbia City 4 <.003 -- -- <.003 -- -- <.00

 Beaver 4 <.003 -- -- <.003 -- -- <.00

 Willamette River 10 <.003 <.003 <.003 <.003 <.003 <.003 .00

Multnomah Channel 4 <.003 -- -- <.003 -- -- <.00

 Sandy River 3 <.003 -- -- <.003 -- -- <.00

 Lewis River 4 <.003 -- -- <.003 -- -- <.00

 Kalama River 4 <.003 -- -- <.003 -- -- <.00

 Cowlitz River 4 <.003 -- -- <.003 -- -- <.00

 All sites 45 <.003 <.003 <.003 <.003 <.003 <.003 .00

Pronamide

 Warrendale 4 <.018 -- -- <.018 -- -- <.01

 Hayden Island 4 <.018 -- -- <.018 -- -- <.01

 Columbia City 4 <.018 -- -- <.018 -- -- <.01

 Beaver 4 <.018 -- -- <.018 -- -- <.01

 Willamette River 10 <.018 <.018 <.018 <.018 <.018 .029 .03

Multnomah Channel 4 <.018 -- -- <.018 -- -- <.01

 Sandy River 3 <.018 -- -- <.018 -- -- <.01

 Lewis River 4 <.018 -- -- <.018 -- -- <.01

 Kalama River 4 <.018 -- -- <.018 -- -- <.01

 Cowlitz River 4 <.018 -- -- <.018 -- -- <.01

 All sites 45 <.018 <.018 <.018 <.018 <.018 <.018 .03

Simazine

 Warrendale 4 <.005 -- -- <.005 -- -- <.00

 Hayden Island 4 <.005 -- -- <.005 -- -- <.00

 Columbia City 4 <.005 -- -- <.005 -- -- .00

Table 36. Distribution of organic-compound concentrations in filtered water, lower Columbia River Basin, Orego

Washington, 1994—Continued

[The term “filtered water” is an operational definition referring to the chemical analysis of that portion of a water-suspended sediment sam

through a nominal 0.70-micrometer filter; to avoid statistical bias that may be associated with constituents analyzed more than once at a s

element concentration per month was statistically summarized; concentrations are reported in micrograms per liter; acetochlor, azinphos-

benfluralin, butylate, cyanazine, 4,4’-DDE, dieldrin, 2,6-diethylaniline, dimethoate, disulfoton, ethalfluralin, alpha-HCH, gamma-HCH (lin

malathion, methyl parathion, molinate, parathion, pebulate, pendimethalin, cis-permethrin, phorate, propachlor, propanil, propargite, tebu

terbufos, thiobencarb, and trifluralin are not included in this table, because no samples had concentrations greater than their correspondin

detection limit; see table 9 for Chemical Abstracts Services registry numbers and method detection limits; see table 7 for full site names; -- 

than 6 samples were collected, therefore the percentile was not calculated; <, less than]

 Site name

Number

of

samples

Minimum

value

Value at indicated percentile Maxim

valu

10 25 50 75 90
112

Simazine—Continued

 Beaver 4 <0.005 -- -- <0.005 -- -- 0.01

 Willamette River 10 .005 0.005 0.010 .030 0.064 0.072 .07

Multnomah Channel 4 <.005 -- -- .012 -- -- .03

 Sandy River 3 <.005 -- -- <.005 -- -- <.00

 Lewis River 4 <.005 -- -- <.005 -- -- <.00

 Kalama River 4 <.005 -- -- <.005 -- -- <.00

 Cowlitz River 4 <.005 -- -- <.005 -- -- <.00

 All sites 45 <.005 <.005 <.005 <.005 .010 .045 .07

Terbacil

 Warrendale 4 <.007 -- -- <.007 -- -- <.00

 Hayden Island 4 <.007 -- -- <.007 -- -- <.00

 Columbia City 4 <.007 -- -- <.007 -- -- <.00

 Beaver 4 <.007 -- -- <.007 -- -- <.00

 Willamette River 10 <.007 <.007 <.007 <.007 .028 .075 .08

Multnomah Channel 4 <.007 -- -- <.007 -- -- .01

 Sandy River 3 <.007 -- -- <.007 -- -- <.00

 Lewis River 4 <.007 -- -- <.007 -- -- <.00

 Kalama River 4 <.007 -- -- <.007 -- -- <.00

 Cowlitz River 4 <.007 -- -- <.007 -- -- <.00

 All sites 45 <.007 <.007 <.007 <.007 <.007 0.014 .08

Triallate

 Warrendale 4 <.001 -- -- <.001 -- -- <.00

 Hayden Island 4 <.001 -- -- <.001 -- -- <.00

 Columbia City 4 <.001 -- -- <.001 -- -- <.00

 Beaver 4 <.001 -- -- <.001 -- -- <.00

 Willamette River 10 <.001 <.001 <.001 <.001 <.001 .008 .00

Multnomah Channel 4 <.001 -- -- <.001 -- -- <.00

 Sandy River 3 <.001 -- -- <.001 -- -- <.00

 Lewis River 4 <.001 -- -- <.001 -- -- <.00

 Kalama River 4 <.001 -- -- <.001 -- -- <.00

 Cowlitz River 4 <.001 -- -- <.001 -- -- <.00

 All sites 45 <.001 <.001 <.001 <.001 <.001 <.001 .00

Table 36. Distribution of organic-compound concentrations in filtered water, lower Columbia River Basin, Orego

Washington, 1994—Continued

[The term “filtered water” is an operational definition referring to the chemical analysis of that portion of a water-suspended sediment sam

through a nominal 0.70-micrometer filter; to avoid statistical bias that may be associated with constituents analyzed more than once at a s

element concentration per month was statistically summarized; concentrations are reported in micrograms per liter; acetochlor, azinphos-

benfluralin, butylate, cyanazine, 4,4’-DDE, dieldrin, 2,6-diethylaniline, dimethoate, disulfoton, ethalfluralin, alpha-HCH, gamma-HCH (lin

malathion, methyl parathion, molinate, parathion, pebulate, pendimethalin, cis-permethrin, phorate, propachlor, propanil, propargite, tebu

terbufos, thiobencarb, and trifluralin are not included in this table, because no samples had concentrations greater than their correspondin

detection limit; see table 9 for Chemical Abstracts Services registry numbers and method detection limits; see table 7 for full site names; -- 

than 6 samples were collected, therefore the percentile was not calculated; <, less than]

 Site name

Number

of

samples

Minimum

value

Value at indicated percentile Maxim

valu

10 25 50 75 90
113

ATRAZINE

METOLACHLOR

SIMAZINE

DEETHYLATRAZINE

EPTC

TERBACIL

DCPA

DIAZINON

NAPROPAMIDE

ORGANIC COMPOUND

0

100

20

40

60

80

FREQUENCY OF DETECTION, IN PERCENT

LOWER COLUMBIA RIVER

 BASIN

WILLAMETTE RIVER AND

 MULTNOMAH CHANNEL

Figure 34. Frequency of detection for selected organic

compounds in the lower Columbia River Basin, Oregon and

Washington, 1994. (Lower Columbia River Basin = 31

samples and excludes the Willamette River at Portland and

Multnomah Channel near mouth; Willamette River Basin =

14 samples and includes the Willamette River at Portland

and Multnomah Channel near mouth)

Kd = Cs/ Ce(2)

where Cs is the concentration of atrazine sor

specific weight of suspended sediment in nan

per gram (ng/g) and Ce is the concentration 

atrazine dissolved in an equal weight of wat

nanograms per milliliter (ng/mL). During th

November 3, 1994 sampling in the Willamett

the foc was 0.03, the concentration of dissol

atrazine was 0.130 ng/mL, and the concentra

suspended sediment was 0.081 g/L. Thus, gi

Koc of 160 and a foc of 0.03,

Kd (mL/g) = 160 x 0.03 = 4.8 mL/g

When the Kd and the Willamette River’s dis

atrazine concentration are substituted into eq

2,

4.8 mL/g = Ce ng/g / 0.130 ng/mL

Ce = 0.63 ng/g

the concentration of atrazine on suspended s

was equal to 0.63 ng/g. The concentration o

suspended sediment in the Willamette River 

J F M A M J J A S O N D

1994

0

120

20

40

60

80

100

DAILY-MEAN STREAMFLOW, IN THOUSANDS OF CUBIC FEET PER SECOND

DAILY-MEAN STREAMFLOW

ATRAZINE CONCENTRATION

Figure 35. Relation between daily mean streamflow and atrazine concentrations in filtered water in the Willamette R

Portland, lower Columbia River Basin, Oregon, 1994. (The term “filtered water” is an operational definition referring t

chemical analysis of a water-suspended sediment sample that passes through a nominal 0.70-micrometer filter.)
114

0.081 g/L, thus 0.051 ng/L of atrazine was

transported on suspended sediment and 0.130ng/mL

was transported in the dissolved phase. On the basis

of this calculation, only 0.04 percent of the total

atrazine was transported in the suspended phase.

Using data from the December 2, 1994 sampling in

the Willamette River, only 0.05 percent of the total

atrazine was transported in the suspended phase.

Although equilibrium calculations clearly

demonstrate atrazine’s affinity for the dissolved

phase, the presence of freshly eroded agricultural

soils in waterways may enhance dissolved atrazine

concentrations. The work of Squillace and Thurman

(1992) suggests that atrazine concentrations in

agricultural soils are high (greater than 2 mg/g

[micrograms per gram]) following atrazine

application in spring, because the organic-carbon

content of soil typically ranges from 1 to 5 percent

and the soil moisture is less than 20 percent. Under

these conditions, 95 percent of the atrazine is

sorbed to soils. During intense rainfall, however,

atrazine temporarily may be transported on

suspended sediment from agricultural fields to

waterways. When the suspended-sediment

concentration of the sediment-water mixture from

the agricultural field decreases to less than 50 g/L,

atrazine desorbs (50 percent sorbed) to the filtered

form (Squillace and Thurman, 1992).

Concentrations of atrazine in the Willamette

River from November to December were as large as

0.180 mg/L and affected atrazine concentrations in

the main stem and Multnomah Channel (fig. 36).

The effect on the lower Columbia River Basin of the

high atrazine concentrations from the Willamette

River was seen in the Multnomah Channel (0.16

mg/L) and Columbia River near Columbia City

(0.02 mg/L). An identical, but attenuated, atrazine

pattern exists from August to September, a period of

low streamflow in the Willamette River and

Columbia River (fig. 36). During August and

September, atrazine was also measurable in the

Columbia River at Beaver Army Terminal. Seasonal

variations in simazine and metolachlor

concentrations in the Willamette River and

Columbia City closely mirror those of atrazine.

The significance of the Willamette River as a

source of atrazine to the lower Columbia River is

evident during periods of high streamflow in the

Willamette River Basin. Between November 3rd

and 9th, 1994, atrazine was measured from f

water samples in the Columbia River at War

(estimated 6 ng/L [nanograms per liter]), Wi

River at Portland (130 ng/L), and Columbia 

near Columbia City (20 ng/L). The average 

mean streamflow in the Willamette River for 

day period (47,000 ft3/s) is high. On the bas

streamflow data for the period 1972–87 (Mo

others, 1990, p. 292), a streamflow of 47,000 

was equaled or exceeded only about 27 perc

the time. During the 7-day period of samplin

Figure 36. Atrazine concentrations in filtered wate

November to December and from August to Septe

lower Columbia River Basin, Oregon and Washing

0.0001

1

0.001

0.01

0.1

ATRAZINE, IN MICROGRAMS PER LITER

MAIN STE

TRIBUTA

WARRENDALE

SANDY RIVER

HAYDEN ISLAND

WILLAMETTE RIVER

LEWIS RIVER

MULTNOMAH CHANNEL

COLUMBIA CITY

KALAMA RIVER

COWLITZ RIVER

SITE NAME

0

0.012

0.002

0.004

0.006

0.008

0.010

ATRAZINE, IN MICROGRAMS PER LITER

Method detection 

NOVEMBER-DECEMBER

AUGUST-SEPTEMBER

Method detection 
115

atrazine load in the Willamette River (54 lbs/d) was

nearly 14 times that at Warrendale (3.9 lbs/d), while

the streamflow in the Willamette River (although

large for the Willamette River) was less than onehalf the average daily mean streamflow for thesame

7-day period at Warrendale (115,000 ft3/s). The

significance of the Willamette River atrazine load

was further confirmed downstream in the Columbia

River near Columbia City where an instantaneous

atrazine load of 25 lbs/d was measured on

November 9. The smaller atrazine load at Columbia

City is probably a result of decreasing Willamette

River streamflows, which decreased from 76,600

ft3/s on November 3 (the day the Willamette River

was sampled) to only 43,000 ft3/s on November 9

(the day Columbia City was sampled).

Unquestionably, the Willamette River is the single

largest source of atrazine to the lower Columbia

River.

Fecal-Indicator Bacteria

 The transmission of pathogenic

microorganisms in water can be associated with

fecal contamination from warm-blooded animals,

including man (U.S. Environmental Protection

Agency, 1976). Fecal-coliform, enterococcal, and

fecal-streptococcal bacteria are indicators of fecal

contamination in water. These bacteria are found in

the gut of warm-blooded animals, but also may be

associated with soils, vegetation, and insects. Thus,

the occurrence of any of these bacteria does not

conclusively indicate the presence of fecal

contamination. Unless the source of the indicator

bacteria has been determined by species

identification to be nonfecal, the presence of an

indicator bacterium indicates a potential health

hazard.

 Washington and Oregon standards for fecalindicator bacteria are based on EPA criteria (U.S.

Environmental Protection Agency, 1976, 1986b).

Currently (1994), the Columbia River is categorized

as a class A stream by the WDOE (State of

Washington, 1992), where fecal-coliform

concentrations shall not exceed a geometric-mean

concentration (based on at least five samples per

month) of 100 colonies per 100 mL of water, with

not more than 10 percent of the samples exceeding

200 colonies per 100 mL. ODEQ’s standard for

indicator bacteria states that fecal-coliform

concentrations should not exceed a log-mean

concentration of 200 colonies per 100 mL, w

than 10 percent of the samples exceeding 40

colonies per 100 mL (State of Oregon, 1994

Neither WDOE nor ODEQ had an enterococ

standard in 1994. In 1992, Oregon had a geo

mean enterococci standard of 31 colonies pe

mL, with less than 61 colonies per 100 mL f

percent of the samples. Because the geometr

log-mean values are used with at least five s

collected within 30 days, and because the cu

(1994) data set consists of monthly samples

standard for Washington and Oregon of 200 

fecal-coliform colonies, respectively, per 10

will apply. To aid in the screening of the dat

report, fresh waters regulated by Oregon wit

concentration of 31 or more enterococci colo

100 mL or 200 or more fecal-coliform or fec

streptococci colonies per 100 mL will be con

to be concentrations of concern (table 37). F

waters regulated by Washington with a conce

of 100 or more colonies of fecal-coliform or 

streptococci colonies per 100 mL will also b

considered of concern. Multiple-indicator ba

tests have been used because of the high var

(lack of precision) within any one test. Whe

different indicator tests have similar results, 

the data have greater assurance that the magn

observed concentrations are real and reprodu

Table 37. Indicator-bacteria standards and concent

of concern for Oregon and Washington streams, low

Columbia River Basin, 1994

[Standards are the geometric or log mean of at least 5 samples c

within 1 month with not more than 10 percent of the samples ex

two times the mean; since the data set for the lower Columbia R

Basin includes only 1 sample per month, the higher values are u

the standard; values are reported in colonies per 100 milliliters o

-- indicates not applicable]

Standard Concern

State

Fecal

coliform

Fecal

coliform Enterococcistre

Oregon a

a

State of Oregon, 1994.

400 200 31 b

bFederal standard is 33 per 100 milliliters,

U.S. Environmental Protection Agency, 1986b.

Washington c

c

State of Washington, 1992.

200 100 -- 
116

For more detail, see the “Quality Assurance”

section at the end of this report.

Table 38 presents a statistical summary of the

indicator-bacteria data collected for each site during

the 1994 sampling period. Only one sample, from

more than 200 indicator-bacteria tests, exceeded the

Washington State standard; the Oregon State

standard was not exceeded. This single exceedance,

which was from the Cowlitz River, is consistent

with the results of an indicator-bacteria study

performed by the WDOE in 1992 of recreational

areas in the Columbia River (Washington

Department of Ecology, 1993). In the WDOE study,

fecal-coliform concentrations in samples from near

the mouth of the Cowlitz River and near the mouth

of the Willamette River also were found to exceed

the State standards. Table 38 also shows that there

were several sites and times when indicator-bacteria

concentrations were at the level of concern. This is

particularly true of the Willamette River at Portland

and Columbia River at Beaver Army Terminal sites,

at which there were concentrations of concern in

more than one fecal-indicator test. However, for

most of the time and for most of the other sites there

were no concentrations of concern.

Analysis of the indicator-bacteria data for

seasonal variability showed that many of the

samples deemed “concentrations of concern” were

collected in September, with higher concentrations

also occurring in the months of January, April,

October, November, and December. It is possible

that fall and winter storms were responsible for the

higher concentrations during these months.

However, a plot of streamflow versus bacteria count

in the Columbia River did not reveal a significant

relation. Very few high concentrations were

observed during the months of June, July, and

August. It is a positive sign, relative to humanhealth concerns, that during periods of high watercontact recreational activities, high bacteria counts

were not observed.

To determine whether the patterns of indicator

bacteria observed in 1994 were similar to concentrations over a longer time period, 1976–94 fecalcoliform data were analyzed from the USGS

NASQAN sites at the Columbia River at Warrendale

and Willamette River at Portland

(fig. 37). The Columbia River at Warrendale has

consistently had low concentrations of fecalcoliform bacteria with no significant seasonal

0

500

1000

1500

2000

2500

3000

0

10

20

30

40

FECAL COLIFORM, IN COLONIES PER 100 MILLILITERS

COLUMBIA RIVER AT WARRENDALE

WILLAMETTE RIVER AT PORTLAND

J FM A A SOND M J J

YEARS 1976-94

(13)

(13)

(17)

(16)

(17)

(11)

(11)

(16)

(14)

(21)

(18)

(12)

(13) Number of samples

(16)

(8)

(15)

(9)

(14)

(9)

(15)

(9)

(11)

(7) (12)

(9) Values not shown:

03/04/1981 3,000 colonies

09/14/1987 4,440 colonies

11/29/1977 5,000 colonies

EXPLANATION

Less than 1.5 times the

 interquartile range from

 the 75th percentile

75th percentile

Median

25th percentile

Less than 1.5 times the

 interquartile range from

 the 25th percentile

Interquartile range equals the value

 of the 75th percentile minus the

 value of the 25th percentile.

1.5 to 3 times the

 interquartile range from

 the 75th percentile

1.5 to 3 times the

 interquartile range from

 the 25th percentile

More than 3 times the

 interquartile range from

 the 75th percentile

Figure 37. Distribution of fecal-coliform bacteria

concentrations in the Columbia River at Warrendal

and Willamette River at Portland, Oregon, 1976-94
117

Table 38. Distribution of fecal-indicator bacteria concentrations, lower Columbia River Basin, 1994

[To avoid statistical bias that may be associated with constituents analyzed more than once at a site, only one concentration per month wa

summarized; values are reported in colonies per 100 milliliters of water; see table 7 for full site names; USGS, U.S. Geological Survey; O

Department of Environmental Quality; WDOE, Washington Department of Ecology; -- indicates fewer than 5 samples were collected, the

percentile was not calculated; a bold number indicates a concentration of concern; a bold number and shaded cell indicates a value that ex

standards; see table 37 for quantification of concentrations of concern and standards]

Site name Agency Number of

samples

Minimum

value

Value at indicated percentile Maxim

valu

25 50 75

Fecal coliform

Warrendale USGS 11 1 1 2 3 5

Hayden Island USGS 12 3 5 8 17 100

Columbia City USGS 11 2 6 20 24 26

Beaver Army Terminal USGS 11 3 5 11 32 110

Sandy River ODEQ 10 2 4 8 33 130

Willamette River USGS 11 1 13 80 130 140

Willamette River ODEQ 8 4 11 19 106 170

Multnomah Channel USGS 11 9 16 24 62 160

Lewis River USGS 4 4 -- 6 -- 8

Lewis River WDOE 10 2 5 11 29 100

Kalama River USGS 4 12 -- 21 -- 30

Kalama River WDOE 10 2 5 12 52 71

Cowlitz River USGS 4 7 -- 10 -- 16

Cowlitz River WDOE 10 4 11 22 55 21,000

Enterococci

Warrendale USGS 10 1 1 1 3 25

Hayden Island USGS 12 <1 1 4 6 9

Columbia City USGS 11 1 2 4 7 10

Beaver Army Terminal USGS 11 1 3 4 25 150

Sandy River USGS 4 4 -- 6 -- 33

Sandy River ODEQ 10 5 5 5 22 50

Willamette River USGS 12 6 16 26 71 520

Willamette River ODEQ 8 5 5 10 14 80

Multnomah Channel USGS 11 1 6 11 15 42

Lewis River USGS 4 1 -- 2 -- 5

Kalama River USGS 4 1 -- 6 -- 40

Cowlitz River USGS 4 1 -- 4 -- 57

Fecal streptococci

Warrendale USGS 6 1 1 1 3 5

Beaver Army Terminal USGS 6 2 7 34 140 440

Willamette River USGS 9 14 17 42 130 1,100
118

variability. The Willamette River at Portland,

however, had much higher, more variable

concentrations, especially during fall and winter

months, when storms are numerous. The likely

explanation for the differences between these two

sites is that the Columbia River site is not

immediately below an urban area, whereas the

Willamette River at Portland receives combined

storm- and sanitary-sewer runoff during storms.

Radionuclides

Radionuclides in the lower Columbia River

Basin were monitored by the Oregon Health

Division from 1961 to 1993 (Oregon Health

Division, Radiation Protection Services, 1994a,

1994b). No measured constituents exceeded any

domestic or international standards during that

period. However, concern about radionuclides does

exist due to the Trojan nuclear power plant near

Goble, Oregon, the Hanford Nuclear Reservation in

eastern Washington, and fallout from nuclear testing

and accidents worldwide.

Radionuclide activity in the Lower Columbia

River, as measured at the Columbia River at Goble,

Oregon (river mile 74), has declined dramatically

since monitoring began there in 1962 (Oregon

Health Division, 1994a, 1994b). Gross beta activity

in surface waters at the Goble site has fallen from a

maximum of 310 pCi/L (picocuries per liter) during

the 1962 to 1967 period to a maximum of 4 pCi/L

during the 1984 to 1993 period. In contrast, gross

alpha activities in surface waters at the Goble site

have remained constant, with a maximum of less

than 2 pCi/L for 1968–72 and 2 pCi/L for 1984–93.

No data are available for gross alpha at the Goble

site for 1962–72.

Additionally, data indicate that radionuclide

activities either declined or remained stable for

streambed sediments and aquatic flora in the lower

Columbia River. For example, Zn-65 activity in

streambed sediments and Cladophora (an alga)

declined from measured maximum activities of 100

and 340 pCi/gram, respectively, during 1962–67 to

less than 0.1 and less than 0.2 pCi/gram,

respectively, for 1978–83 (Oregon Health Division,

1994a, 1994b). Monitoring for Zn-65 activity in the

lower Columbia River stopped in 1983. Those

radionuclides measured during 1989–93 at Goble—

K-40, Ra-226, Cs-137, Be-7, Th-232—generally

had low maximum activities in streambed se

and Cladophora. In streambed sediments, m

maximum activities were 17.0, 0.8, 0.2, < 1.

0.8 pCi/gram, respectively. Similarly, in clad

measured maximum activities were 5.7, < 0.

and 1.1 pCi/gram, respectively—Th-232 wa

measured in Cladophora. Activities for K-40 

higher than other measured radionuclides, p

because it is naturally occurring. All measur

activities were below standards established b

international and domestic agencies for the

Columbia River (Oregon Health Division, 19

1994b).

QUALITY ASSURANCE

Quality-assurance data have been used, 

degree possible, in the Bi-State monitoring p

to quantify accuracy, precision, presence of

laboratory contamination, and analytical bia

Analytical bias is important to the Bi-State p

because water-quality data were collected an

analyzed by multiple agencies (ODEQ, WDO

USGS) and laboratories. Statistics generated 

the quality-assurance data were used in the

interpretation of Bi-State data and should be

consulted by other users.

Examples of Quality-Assurance Data

The quality-assurance program for amb

monitoring involved various types of quality

assurance samples for constituents in filtered 

unfiltered water and in suspended sediment. 

types of quality assurance are as follows:

(A) SOURCE SOLUTION BLANK—

Contaminant-free water (for example, distill

deionized water) was shipped to the laborato

disguised as a routine sample. The source so

blank is a measure of contamination from so

other than sample collection and processing

example, contaminants present in the atmosp

the interior of sample bottles, in preservative

laboratory environment, and so on.

(B) FIELD EQUIPMENT BLANK—A 

of contaminant-free water is passed through 

sampling and processing equipment that an 

water sample would contact (for example, th

sampler, sample splitter, pump, tubing, filter
119

holder, and sample bottle). The blank sample is then

preserved and analyzed with the batch of actual

samples. Field equipment blanks are used to show

that (1) the equipment-cleaning protocol adequately

removes contamination introduced from previous

sampling, (2) the sampling and processing protocol

does not result in contamination, and (3), the

handling and transport of sampling equipment and

supplies between sample collections do not

introduce contamination.

(C) SPLIT SAMPLES—Large sample volumes

of ambient water are divided into two or more equal

volumes and sent to one or more laboratories. Split

samples provide an estimate of precision within and

between labs. These comparisons are especially

important when multiple laboratories are used in a

study. In the current study, samples were split using

a 10-L churn splitter.

(D) STANDARD REFERENCE SAMPLES—

Samples of a known chemical concentration

(analyzed multiple times to determine a most

probable value [median]and an F-pseudosigma

value7) were disguised as routine samples and

shipped to the laboratory. Reference samples do not

come in contact with sampling or processing

equipment. Results from standard reference samples

are used to assess analytical accuracy.

(E) FIELD MATRIX SPIKES—A spike

solution of known concentration is added to a split

of ambient sample water and is processed and

analyzed according to standard protocols. Samples

may be sent to one lab or several laboratories. Field

matrix spikes are used to assess analytical precision

and recoveries of analytes from matrices of ambient

water samples. Multiple split samples that have

been spiked can be used to measure precision.

(F) SURROGATE SPIKES—Organic

compounds that are expected to behave similarly to

target analytes are spiked into each sample

following filtration (to remove particulate matter)

and prior to passing the sample through the solid

phase extraction cartridge. Data from surrogate

spikes are used to assess target analyte recovery and

when aggregated over longer periods of time

7

F-pseudosigma is equivalent to the standard deviation of traditional statistics when the data conform to a Gaussian distribution.

Values greater than or less than the accepted value by 2 x F-pseudosigma, respectively, are considered lower- and upper-warning

levels (Long and Farrar, 1995).

(months for example), can be used to assess 

term analytical precision. Surrogate spike da

published in the USGS’s water-data report (

Geological Survey, 1995). Surrogate data sh

interpreted with caution, however. Dependin

conditions, surrogate recoveries may not be

representative of all target analytes.

Use of Quality-Assurance Results to

Interpret Environmental Data

The quality-assurance data have been o

and presented below to aid with the interpre

the environmental data by quantifying accur

precision, bias, and contamination. To this e

data have been organized into the following 

1. Field measurements;

2. Major ions;

3. Nutrients;

4. Indicator bacteria, chlorophyll a, suspend

sediment, suspended solids, and organic c

5. Filtered trace elements;

6. Suspended trace elements; and

7. Filtered organic compounds.

Although the quality-assurance data co

several constituent groups, data within each 

were often few in number, which precluded 

comprehensive analysis.

Table 39 lists quality-assurance data fo

measurements of water temperature, specific

conductance, pH, dissolved oxygen, and alk

On the basis of limited quality assurance dat

temperature, specific conductance, and alkal

values were similar for ODEQ and USGS

measurements in the Sandy River. For the cu

study, water temperature, specific conductan

alkalinity data were aggregated into a single 

for interpretation. Dissolved oxygen and pH

measurements between agencies were not

comparable, however. Because the number o

assurance samples was small, it is not possib

conclude that differences exist between agen

Instead, additional joint quality-assurance sa

need to be collected. If differences exist betw

agencies, field sampling protocols should be

amended accordingly.

Quality-assurance data for major ions c

by the USGS are listed in table 40. Review o

split, standard-reference, and equipment-bla

samples, respectively, show that precision, a
120

and absence of extraneous contamination were

acceptable.

Analyses of a limited number of blind standard

reference samples for nutrients show that the USGS

laboratory had acceptable accuracy for its nutrient

determinations (table 41). The only nutrient species

close to a warning level was phosphorus in

unfiltered water, for which standard reference

samples N-38 and N-40 had concentrations near the

lower warning level. For example, the phosphorus

concentration for standard reference sample N-38

(0.09 mg/L) was smaller than the most probable

value by 0.03 mg/L, which slightly exceeds two

times the F-pseudosigma value and is near the lower

warning level. Analysis of the USGS depth- and

width-integrated sample, split between the USGS

and ODEQ laboratories, shows general agreement

among nutrient species, and, likewise, no gross

differences exist for the grab sample split between

the USGS and ODEQ laboratories.

Laboratory precision associated with analyses

of bacteria, chlorophyll a, and suspended sediment

was assessed by splitting a depth- and widthintegrated sample between the USGS and ODEQ

laboratories (table 42). Indicator bacteria counts for

the ODEQ data were somewhat variable and

exceeded counts made from the USGS split. These

differences indicate the inherent difficulty in

making intersite and intrasite comparisons of

bacteria data. Although a grab sample for bacteria

was collected, in addition to the depth- and widthintegrated sample, the data were too variable to

assess differences in enumeration between sampling

methods. The sample split for chlorophyll a had a

lower concentration in the USGS split than in the

ODEQ split; additionally, the ODEQ compar

chlorophyll a collected by depth- and width

integrated versus grab-sampling techniques 

nearly identical concentrations between sam

methods. The differences in chlorophyll

concentrations between laboratories may be

indicative of variable precision; however, da

too few to make any definitive conclusion. T

samples split between laboratories for compa

the USGS suspended-sediment determinatio

the ODEQ suspended-solids determination h

suspended-sediment concentration in the US

sample (8 mg/L) that was nearly three times 

than in the ODEQ split. Differences between 

ratories may be indicative of the bias or disc

mination inherent in grab sampling methods 

to obtaining representative quantities of coa

grained suspended sediment. Ideally, howev

for differences between sampling methods sh

made during periods of high streamflow, wh

suspended sediment and coarse-grain sized s

concentrations are high. Conversely, the sim

between the grab sample and the depth- and 

integrated sample, which were both analyze

the ODEQ suspended-solids method, sugges

differences may exist between the suspended

sediment and suspended-solids method. Las

precision for suspended and filtered-water o

carbon determinations was acceptable.

Quality-assurance data for filtered-wate

elements for the USGS included one split sa

the Sandy River, one laboratory blank, five

equipment blanks, and one blind standard-re

sample (table 43). All quality-assurance sam

were sent to the USGS laboratory as “blind

samples.” There were acceptable levels of pr

Table 39. Quality-assurance data for field measurements, lower Columbia River Basin, Oregon, 1994

[°C, degrees Celsius; μS/cm, microsiemens per centimeter; mg/L, milligrams per liter; USGS, U.S. Geological Survey; ODEQ, Oregon

Department of Environmental Quality; CaCO3, calcium carbonate]

Site name Agency Date Time

Water

temperature,

in °C

Specific

conductance,

in μS/cm

pH, whole

water field,

in

standard

units

Dissolved

oxygen,

in mg/L

Alkal

fie

in m

 a

CaC

Sandy River

near Troutdale

USGS 08-15-1994 1105 20.0 70 7.9 9.7 21

Sandy River

near Troutdale

ODEQ 08-15-1994 1025 19.0 72 7.5 9.0 20
121

Table 40. Quality-assurance data for major ions, lower Columbia River Basin, Oregon, 1994[All values reported are from filtered-water samples; the term “filtered water” is an operational definition referring to the chemical analysis of that portion of a watethrough a nominal 0.45-micrometer filter; values are reported in milligrams per liter; silica is reported as SiO2; TDS, total dissolved solids at 180 degrees Celsius; S

Oregon; <, less than; --, not applicable; SRM, Standard-Reference Material; MPV, Most-Probable Value; F-pseudosigma is equivalent to one standard deviation fo

Sample description Date Time Calcium Magnesium Sodium Potassium Chloride Sulfate 

Split samples

Sandy River 07-07-1994 1005 4.1 1.5 3.2 0.40 1.7 4.0 Sandy River 07-07-1994 1010 4.2 1.6 3.3 .50 1.8 4.1 

Blind standard-reference sample

SRM M-126 05-16-1994 1043 8.1 1.6 17 2.7 -- -- MPV -- -- 7.62 1.62 17.8 2.62 -- -- F-pseudosigma -- -- .46 .078 .77 .178 -- -- 

Equipment-blank sample

Equipment blank 12-08-1994 1112 <.10 <.10 <.10 <.10 -- -- 
122

Table 41. Quality-assurance data for nutrients, lower Columbia River Basin, Oregon, 1994[All values reported are from filtered-water samples, unless otherwise stated; the term “filtered water” is an operational definition referring to the chemical analysis sediment sample that passes through a nominal 0.45-micrometer filter; conversely, the term “unfiltered water” refers to the chemical analysis of a water sample that in any way altered from the original matrix; values are reported in milligrams per liter; N, nitrogen; USGS, U.S. Geological Survey; <, less than; ODEQ, Oregon Dnot analyzed or not applicable; SRM, Standard-Reference Material; MPV, Most-Probable Value; F-pseudosigma is equivalent to one standard deviation of a norma

Sample description Date Time Ammonia Ammonia plus organic N Ammonia plus organic N, unfiltered Nitrite Nitrite plus nitrate Pho

pho

Split samples between agencies

Sandy River, USGS analysis of USGS integrated sample

08-15-1994 1105 <0.010 <0.20 <0.20 <0.010 0.074 0

Sandy River, ODEQ analysis ofUSGS integrated sample

08-15-1994 1020 -- -- -- .020 <.20 .

Sandy River, USGS analysis ofODEQ grab sample

08-15-1994 1024 <.010 <.20 <.20 <.010 <.050 

Sandy River, ODEQ analysis ofODEQ grab sample

08-15-1994 1025 .040 -- <.20 -- .030 -- 

Blind standard-reference samples

USGS analysis of SRM N-38 08-15-1994 1110 .070 <.20 <.20 .060 .200 

MPV for N-38 -- -- .087 -- .20 -- .210 -- F-pseudosigma for N-38 -- -- .017 -- .158 -- .018 -- USGS analysis of SRM N-40 08-31-1994 1047 <.010 <.20 .20 .030 .120 .

MPV for N-40 -- -- .024 -- .118 -- .110 -- F-pseudosigma for N-40 -- -- .027 -- .098 -- .012 -- 

USGS split samples

Sandy River 07-07-1994 1005 .010 <.20 < .20 <.010 <.050 <Sandy River 07-07-1994 1010 .010 <.20 <.20 <.010 <.050 <
123

Table 42. Quality-assurance data for fecal-indicator bacteria, chlorophyll a, suspended sediment, suspended solids, and organic carb

Oregon, 1994

[cols/100mL, colonies per 100 milliliters of water; mg/L, milligrams per liter; the term “filtered water” is an operational definition referring to the chemical analysisediment sample that passes through a nominal 0.45-micrometer filter; Sandy River, Sandy River near Troutdale, Oregon; USGS, U.S. Geological Survey; K, nonidapplicable; ODEQ, Oregon Department of Environmental Quality]

Sample description Date Time

Fecal

coliform,

in cols/

100mL

Enterococci,

in cols/

100mL

Chlorophyll a,

in mg/L

Suspended

sediment,

in mg/L

Suspend

solids,

in mg/L

Split samples between agencies

Sandy River, USGS analysis ofUSGS integrated sample

08-15-1994 1105 K 4 K 4 1.0 8 -- 

Sandy River, ODEQ analysis ofUSGS integrated sample

08-15-1994 1020 11 45 3.0 -- 3 

Sandy River, ODEQ analysis ofODEQ grab sample

08-15-1994 1025 17 10 3.2 -- 3 

USGS split samples

Sandy River 07-07-1994 1005 -- -- -- -- -- Sandy River 07-07-1994 1010 -- -- -- -- -- 
124

Table 43. Quality-assurance data for filtered-water trace elements, lower Columbia River Basin, Oregon, 1994[The term “filtered water” is an operational definition referring to the chemical analysis of that portion of a water-suspended sediment sample that passes through a are reported in micrograms per liter; Sandy River, Sandy River near Troutdale, Oregon; <, less than; --, not analyzed or not applicable; SRM, Standard-Reference MF-pseudosigma is equivalent to one standard deviation for a normal data set]

Sample description Date Time Arsenic Barium Beryllium Cadmium Chromium Cobalt Copper 

Split samples

Sandy River 07-07-1994 1005 <1 2 <1 <1 <1 <1 <1 Sandy River 07-07-1994 1010 <1 2 <1 <1 <1 <1 <1 

Blank samples

Laboratory blank 01-20-1994 1130 <1 <1 <1 <1 <1 <1 <1 Equipment blank 02-16-1994 0927 <1 <1 <1 <1 <1 <1 <1 Equipment blank 04-20-1994 1021 <1 <1 <1 <1 <1 <1 <1 Equipment blank 05-11-1994 0947 <1 <1 <1 <1 <1 <1 <1 Equipment blank 06-29-1994 1033 <1 <1 <1 <1 <1 <1 <1 Equipment blank 08-10-1994 1027 <1 <1 <1 <1 <1 <1 <1 

Blind standard-reference sample

SRM T-125 05-16-1994 1048 10 17 16 7 4 9 17 MPV -- -- 10.2 16.9 15.0 7.2 3.99 9.45 17.4 F-pseudosigma -- -- 1.54 1.67 1.19 .75 .71 .78 2.08 
125

Table 43. Quality-assurance data for filtered-water trace elements, lower Columbia River Basin, Oregon, 1994—Continued[The term “filtered water” is an operational definition referring to the chemical analysis of that portion of a water-suspended sediment sample that passes through a noreported in micrograms per liter; Sandy River, Sandy River near Troutdale, Oregon; <, less than; --, not analyzed or not applicable; SRM, Standard-Reference Materipseudosigma is equivalent to one standard deviation for a normal data set

Sample description Date Time Molybdenum Nickel Silver Zinc Antimony Aluminum Seleni

Split samples

Sandy River 07-07-1994 1005 <1 <1 <1 2 <1 10 <1 Sandy River, 07-07-1994 1010 <1 <1 <1 <1 <1 10 <1 

Blank samples

Laboratory blank 01-20-1994 1130 <1 <1 <1 <1 <1 <1 <1 Equipment blank 02-16-1994 0927 <1 <1 <1 <1 <1 3 <1 Equipment blank 04-20-1994 1021 <1 <1 <1 <1 <1 2 <1 Equipment blank 05-11-1994 0947 <1 <1 <1 <1 <1 <1 <1 Equipment blank 06-29-1994 1033 <1 <1 <1 1 <1 <1 <1 Equipment blank 08-10-1994 1027 <1 1 <1 8 <1 <1 <1 

Blind standard-reference sample

SRM T-125 05-16-1994 1048 19 10 4 4 6 20 9 MPV -- -- 20.1 11.2 3.83 5.95 6.24 24 9.7F-pseudosigma -- -- 1.78 1.04 .60 4.01 1.30 8.56 1.8
126

and accuracy for all constituents—trace elements

were within two times the F-pseudosigma value.

Equipment blanks were generally acceptable;

however, small amounts of aluminum and nickel

were detected infrequently. A higher single

occurrence for zinc (8 μg/L) was measured on

August 8, 1994, and may be indicative of

contamination during sample processing and (or)

analysis. The sample was rerun and the high zinc

confirmed. Ambient waters analyzed during the

month of August, however, had a maximum zinc

concentration of only 2 μg/L. Consequently, the

source of the anomalous zinc concentration is

unclear. The anomaly is of little significance to the

interpretation of current (1994) ambient zinc data

owing to the absence of high zinc concentrations in

ambient waters sampled during August 1994. High

zinc values for ambient waters might have

suggested a more pervasive zinc contamination

problem. Overall, the infrequent occurrence of

contamination in USGS blanks suggests that the

parts-per-billion protocol (Horowitz and others,

1994) currently being used by the USGS is working

well.

Quality-assurance data for suspended trace

elements included a blind standard-reference

sample and two split samples from the Willamette

River at Portland (table 44). Comparison of the

USGS results with the most-probable value given by

Govindaraju (1994) showed accuracy to be within

25 percent, except for titanium, arsenic,

molybdenum, selenium, yttrium, and ytterbium. The

precision was also shown to be within 25 percent,

except for arsenic, cadmium, copper, molybdenum,

and thallium. Except for the constituents listed

above, the results show precision and accuracy to be

good for making comparisons between sites and

times. Contamination is generally not expected to

be a problem with suspended trace elements,

because concentrations are measured in parts per

million (μg/g).

A specific quality-assurance program was

designed to assess accuracy, precision, and

contamination associated with field collection and

laboratory analysis of organic compounds.

Accuracy was assessed by using field matrix spikes.

Precision was assessed by using ambient river-water

splits and field matrix spikes. Contamination was

assessed by using organic-free water for fieldequipment blanks. All four field-equipment blank

samples were less than the method detection 

all analytes. Laboratory surrogate recovery r

are published with the corresponding analyt

in the U.S. Geological Survey Water Resour

Reports for Oregon for the 1994 WY (U.S.

Geological Survey, 1995). Laboratory surrog

recoveries provide an indication of the recov

the target organic compounds.

Statistical summaries for field matrix s

recoveries show that median recoveries rang

as low as 20 percent for cis-Permethrin to as 

130 percent for methyl parathion and terbufo

45). Calculations for the seven field matrix s

were made by subtracting the environmental 

ambient organic compound concentration

(background) from the spiked environmenta

matrix. The theoretical spike concentration w

calculated by determining the mass of the or

compound added to the environmental samp

dividing by the volume of the spiked sample

Recovery was subsequently calculated by di

the background corrected spike concentratio

theoretical spiked concentration, and the mi

median, and maximum recoveries, in percen

shown in table 45. When the environmental

concentration was less than the method dete

limit, its concentration was assumed to be ze

computation purposes. This was the case in 

percent of the calculations.

River-water samples were collected and 

make two replicate samples at each of four s

Replicate results are listed in table 45 as the

difference between the analytical-replicate r

and the mean of the two values (rounded to 

nearest even nanograms per liter). When one 

two concentrations was below the method de

limit, both measured values were reported.

CONSIDERATIONS FOR FUTURE D

COLLECTION ACTIVITIES

The goals of the Bi-State ambient-mon

program were to define existing water-qualit

conditions, characterize water-quality proble

according to magnitude and type, and provid

quality information to support pollution prev

abatement, and resource-management progra

Additionally, ambient-monitoring programs 

provide data for evaluating compliance,

effectiveness of pollution-prevention progra
127

Table 44. Quality-assurance data for suspended trace element samples, lower Columbia River Basin, Oregon, 1994[All values are reported in micrograms per gram, except aluminum, calcium, iron, magnesium, phosphorus, potassium, sodium, and titanium which are in percent; WPortland, Oregon; SRM, Standard-Reference Material; --, not analyzed or not applicable; MPV, Most-Probable Value]

Sample

description Date Time Aluminum Calcium Iron Magne- sium Phos- phorus Potassium Sodium Titanium 

Split samples

WillametteRiver

04-11-1994 1000 8.2 1.5 5.8 1.1 0.16 0.96 0.94 0.78 

WillametteRiver

04-11-1994 1005 8.3 1.5 5.9 1.1 .15 .96 .98 .77 

WillametteRiver

11-03-1994 0956 8.8 1.9 6.1 1.1 .15 .94 1.20 .76 

WillametteRiver

11-03-1994 1001 8.8 1.9 5.8 1.1 .16 .97 1.2 .76 

Blind standard-reference sample

SRM GSD-4 06-30-1994 1200 8.2 5.5 4.0 .6 .05 1.8 .22 .37 MPV -- -- 8.29 5.38 4.13 .63 .048 1.85 .223 .534 

Sample

description Date Time Beryllium Cadmium Chromium Copper Lead Manganese Mercury Molybdenum 

Split samples

WillametteRiver

04-11-1994 1000 <2.0 0.30 80 66 15 1,500 1.50 1.00 

WillametteRiver

04-11-1994 1005 <2.0 <2.00 86 68 17 1,500 1.70 .60 

WillametteRiver

11-03-1994 0956 3.0 .30 72 62 33 1,900 .11 .90 

WillametteRiver

11-03-1994 1001 3.0 .21 74 86 28 1,900 .11 .60 

Blind standard-reference sample

SRM GSD-4 06-30-1994 1200 2 <2 87 36 27 830 .05 .50  MPV -- -- 2.4 .19 81 37.3 30.4 850 .044 .86 
Table 44. Quality-assurance data for suspended trace element samples, lower Columbia River Basin, Oregon, 1994—Continued

[All values are reported in micrograms per gram, except aluminum, calcium, iron, magnesium, phosphorus, potassium, sodium, and titanium which are in percent; WPortland, Oregon; SRM, Standard-Reference Material; --, not analyzed or not applicable; MPV, Most-Probable Value]

Sample

description Date Time Vanadium Zinc Bismuth Cobalt Europium Gallium Holmium Lanthanum Ne

Split samples

WillametteRiver

04-11-1994 1000 180 130 <20 27 <3.0 20 <7.0 30 

WillametteRiver

04-11-1994 1005 180 130 <20 25 <4.0 20 <8.0 26 

WillametteRiver

11-03-1994 0956 170 120 <20 28 <4.0 14 <8.0 24 

WillametteRiver

11-03-1994 1001 170 140 <20 29 <4.0 17 <8.0 26 

Blind standard-reference sample

SRM GSD-4 06-30-1994 1200 120 100 <20 20 <4 19 <8 35 MPV -- -- 118 101 .64 18 1.3 20.5 1.07 40 

Sample

description Date Time Strontium Tantalum Thorium Tin Uranium Yttrium Ytterbium Lithium C

Split samples

WillametteRiver

04-11-1994 1000 210 <70 8.0 <8.0 1.9 29 3.0 29 

WillametteRiver

04-11-1994 1005 210 <80 6.7 <10.0 1.8 27 3.0 29 

WillametteRiver

11-03-1994 0956 260 <80 5.6 <10.0 2.1 30 3.0 28 

WillametteRiver

11-03-1994 1001 250 <80 4.7 <10.0 1.9 28 3.0 28 

Blind standard-reference sample

SRM GSD-4 06-30-1994 1200 140 <80 16.6 <10 2.1 17 <2 53 MPV -- -- 142 1.36 14.6 4.0 2.6 26 2.9 51 
129

Table 45. Quality-assurance data for organic compounds in filtered water, lower Columbia River Basin, Oregon and Washington, 19[The term “filtered water” is an operational definition referring to the chemical analysis of that portion of a water-suspended sediment sample that passes through a mixture was added to all seven field matrix spike samples to increase river-water compound concentrations by 100 ng/L (nanograms per liter); MDL, method-deteminimum; Max, maximum; Difference, the difference in concentrations determined for the split sample; Mean, the mean concentration determined for the split saServices Registry number for each compound; *, both concentrations were found to be below the MDL; #, values were not calculated because one concentration wthe MDL; no quality-assurance data exist for acetochlor because it was added into the analytical schedule after the project had started]

Compound MDL, in ng/L

Field matrix spike

recoveries, in percent

(n, 7)

Split sample concentrations, in ng/L

123

Min Median Max Difference Mean Difference Mean Difference M

Alachlor 2 97 120 140 *****Atrazine 1 97 110 180 1 12 1 46 *Azinphos-methyl 1 54 130 250 *****Benfluralin 2 62 90 100 *****Butylate 2 92 100 120 * * 2 6 *Carbaryl 3 93 160 170 *****Carbofuran 3 76 130 140 58 56 ***Chlorpyrifos 4 90 120 130 2 16 ***Cyanazine 4 86 100 150 *****DCPA (Dacthal) 2 99 120 130 #a #***

4,4’-DDE 6 66 70 77 * * * * 1 Deethylatrazine 2 30 40 110 6 21 * * 5 Diazinon 2 80 100 110 1 26 1 6 1 Dieldrin 1 82 100 120 * * * * 1 2,6-Diethylaniline 3 78 90 110 *****Disulfoton 17 56 130 230 *****EPTC 2 90 108 120 2 19 ***Ethalfluralin 4 75 100 130 *****Ethoprop 3 93 120 140 *****Fonofos 3 85 100 120 2 4 ***alpha-HCH 2 94 120 130 *****gamma-HCH (lindane) 4 86 110 130 4 92 * * #b 

Linuron 2 54 90 160 *****Malathion 5 90 110 150 *****Methyl parathion 6 80 130 140 *****Metolachlor 2 100 120 130 10 31 2 72 0 1
130

Metribuzin 4 82 110 130 *****Molinate 4 97 103 120 *****Napropamide 3 84 101 140 1 10 * * 2 Parathion 4 85 130 140 *****Pebulate 4 93 100 120 *****Pendimethalin 4 67 100 120 *****cis-Permethrin 5 10 20 20 *****Phorate 2 64 90 140 *****Prometon 18 100 110 110 * * * * 1 Pronamide 3 87 100 120 *****Propachlor 7 86 120 130 *****Propanil 4 110 120 130 *****Propargite 13 33 110 140 *****Simazine 5 50 101 120 0 1,300 * * 7 Tebuthiuron 10 <10 88 100 *****Terbacil 7 76 110 140 * * 1 20 3 Terbufos 13 77 130 160 *****Thiobencarb 2 100 120 130 *****Triallate 1 91 100 120 *****Trifluralin 2 66 90 110 *****

aFor DCPA (Dacthal) split 1, the concentrations determined were <2 and 2 ng/L.bFor Lindane split 3, the concentrations determined were <4 and 5 ng/L.

Table 45. Quality-assurance data for organic compounds in filtered water, lower Columbia River Basin, Oregon and Washington, 19[The term “filtered water” is an operational definition referring to the chemical analysis of that portion of a water-suspended sediment sample that passes through a mixture was added to all seven field matrix spike samples to increase river-water compound concentrations by 100 ng/L (nanograms per liter); MDL, method-deteminimum; Max, maximum; Difference, the difference in concentrations determined for the split sample; Mean, the mean concentration determined for the split saServices Registry number for each compound; *, both concentrations were found to be below the MDL; #, values were not calculated because one concentration wthe MDL; no quality-assurance data exist for acetochlor because it was added into the analytical schedule after the project had started]

Compound MDL, in ng/L

Field matrix spike

recoveries, in percent

(n, 7)

Split sample concentrations, in ng/L

123

Min Median Max Difference Mean Difference Mean Difference M
131

detection of water-quality trends over time. From

the water-resource manager’s perspective, ambient

monitoring can provide quantitative information

that can be used to form the basis for water-quality

management decisions that will sustain acceptable

levels of water quality. Where water-quality

concerns exist, however, ambient monitoring can

provide information for evaluating management

options, initiating corrective actions, and evaluating

effectiveness of actions.

Before considering future data-collection

activities, it would be beneficial to summarize and

present the relevant technical information gathered

by the Bi-State committee to water-resource

managers. If all basic water-quality data were stored

in one database that is accessible at all levels,

including Federal, State, local, Tribal, university,

and the general public, the data could be compiled

and utilized more efficiently. The data contained in

the technical-information summary can be used by

water-resource managers to identify water-quality

problems and issues affecting beneficial uses in the

lower Columbia River Basin. Once water-quality

problems and issues have been defined, the

following conceptual framework will provide a

basis for designing and refining water-quality

monitoring programs:

• Develop conceptual models of processes

causing water-quality problems. Address

specifically processes of input, transport

and interaction among media (dissolved,

suspended, and aquatic biota)

• Verify conceptual models with existing

data; where data are inadequate,

supplement ongoing data-collection

activities.

• Determine the validity of conceptual

models using a mass-balance approach. The

conceptual model is verified if loads

between main-stem sites balance. If loads

fail to balance, however, then unaccountedfor loads (sources) remain and, depending

on the magnitude of the unaccounted-for

load, the conceptual model goes through

further iterations until mass balance is

achieved.

•Once mass balance is achieved, design

monitoring programs addressing

constituents of concern. The monitoring

programs should provide more quan

measures to verify conceptual mode

were refined earlier on the basis of e

water-quality data. Ultimately, mon

programs can be developed that effe

target and provide data necessary to 

constituent loadings that previously 

resulted in water-quality concerns.

In addition to the conceptual framewor

presented above, immediate consideration sh

given to the following:

• Initiate coordinated interagency qua

assurance/quality-control programs 

to evaluate accuracy, precision, bias

contamination issues for constituent

concern. Additionally, on the basis 

interagency comparisons of various 

measurements (for example, pH and

dissolved oxygen—described in the 

Assurance” section), immediate

consideration should be given to res

instrument calibration and (or) meas

techniques that may result in discre

between analyzing agencies.

• Supplement the Bi-State database w

ancillary data. To increase the utilit

Bi-State database, add ancillary data 

pertinent to water-quality concerns.

Ancillary data should include land a

water-use information, precipitation 

and quality, point and nonpoint sour

quality data, and fertilizer and pesti

quantities associated with agricultur

activities.

• Continue the collection of monthly

suspended sediment data from the C

River at Kelso. These data and USG

continuous streamflow data from the 

River at Castle Rock could be used 

estimate monthly and annual mean

suspended-sediment loads. On the b

sparse data collected in September 1

Cowlitz River accounted for more th

percent of the suspended-sediment l

the Columbia River at Beaver Army

Terminal. Consequently, better defin

the timing and magnitude of Cowlit

suspended-sediment loads may prov

useful information to water-quality

managers as dredging needs are asse
132

the efficiency of sediment-retention

structures is evaluated.

• Synoptically sample selected sites in the

lower Columbia River Basin during low

streamflows in late summer and again, in

late fall or early spring, during periods of

storm runoff in the Willamette River Basin.

Because sampling dates during the current

study were sometimes separated by days

and weeks, mass-balance calculations were

hampered for periods of storm runoff and

were semiqualitative during periods of low

streamflow.

• Supplement the Bi-State database with

ongoing water-quality measurements made

by other agencies. For example,

measurements made by the U.S. Army

Corps of Engineers for total dissolved gas,

dissolved oxygen, water temperature, and

barometric pressure in the lower main stem,

in addition to pertinent data collected by

the National Biological Service, U.S. Fish

and Wildlife Service, and National Marine

Fisheries Service could be incorporated in

the database. Water-quality data from the

USGS’s NASQAN program at the

Columbia River near Beaver Army

Terminal and Willamette River at Portland

should also be included in the Bi-State

database.

As part of the USGS’s NASQAN sampling

network in the lower Columbia River Basin in 1995,

water-quality samples will be collected from the

Columbia River at Beaver Army Terminal and the

Willamette River at Portland. Each site will be

sampled monthly, in addition to six event-based

samplings. Data collected as part of the NASQAN

program will compliment many of the data collected

in the current Bi-State monitoring program.

SUMMARY

Historically, water-quality studies in the lower

Columbia River have focused on specific river

reaches; many of these studies lack the continuity

necessary to assess water quality in a river-basin

framework. The Bi-State study has addressed this

data gap by initiating an ambient-monitoring

program that will assess temporal variations in

constituent concentrations and loads in 1994

purpose of this report is to describe the water

conditions in the lower Columbia River and 

tributaries, by interpreting data collected hist

and in 1994.

The Columbia River Basin has a draina

of 259,000 square miles. Its drainage basin c

seven northwestern States and one Canadian

Province. The lower Columbia River Basin, 

the focus of this study, includes the subbasin

draining into the Columbia River below Bon

Dam, the largest of which is the Willamette 

The lower Columbia River Basin receiv

annual precipitation ranging from 37 inches 

Portland, Oregon, to 113 inches at Cougar,

Washington. Streamflows in tributaries of th

Columbia River are generally highest during 

winter, but Columbia River streamflows are 

during the spring snowmelt season. The basi

percent forest land and 17 percent agricultur

Most of the agricultural land lies in the Will

River Basin, which accounts for 87 percent 

irrigation withdrawals and 55 percent of the

industrial withdrawals in the lower Columbi

Basin. On the basis of National Pollutant Di

Elimination System permits, 102 municipal 

industrial sites discharge into the lower Colu

River and the first 16 river miles of its tribut

More than one-half of these are sewage-trea

plants, chemical manufacture facilities, or w

products industries.

The U.S. Geological Survey (USGS),

Washington Department of Ecology, and Ore

Department of Environmental Quality collec

water-quality data at 10 sites in the lower Co

River Basin from January to December of 19

Additionally, water-quality data spanning m

50 years and more than 200 parameters were 

for interpretation in this report. Loads of sus

sediment, total dissolved solids, unfiltered-w

phosphorus and filtered-water nitrite plus nit

ammonia were calculated by regressing cons

concentrations against streamflow and time.

Monotonic-time trends were determined for 

temperature, suspended sediment, unfiltered

phosphorus, specific conductance, and total

dissolved solids. Nutrient, major-ion, trace-e

and organic-compound concentrations were s

against U.S. Environmental Protection Agen

(EPA) and State guidelines. Physical and mi
133

biological measurements also were screened against

State guidelines.

On the basis of an analysis of historical watertemperature data, percentile distributions of daily

mean water temperatures were generally uniform

among sites in the main stem of the lower Columbia

River. An earlier USGS study notes that the

principal water-temperature increases were

measured well upstream of the lower Columbia

River, in an area between Grand Coulee Dam and

McNary Dam. Historical data also show that the

temperature gradient is small between the

Willamette River and the main stem of the

Columbia River. Both historical and current data

show that the highest water temperatures in the

lower Columbia River Basin are during August. In

the Columbia River at Bradwood, 75 percent of the

daily mean water temperatures exceeded 20°C, a

“special condition” criterion for the State of

Washington. In 1994, 15 percent of the

instantaneous measurements of water temperature

exceeded 20°C in the lower Columbia River. The

special condition criterion was exceeded

consistently at the four main-stem sites during July

and August —a period coinciding with season-high

air temperatures and low streamflows.

Dissolved-oxygen concentrations vary in

accordance with seasonal changes in water

temperature. Aquatic life in the lower Columbia

River Basin is not subjected to low dissolvedoxygen concentrations. Only the Sandy River at

Troutdale had a dissolved-oxygen concentration

below the Oregon State standard of 90 percent of

saturation. Although concentrations of dissolved

oxygen at the Willamette River and Multnomah

Channel sites were lower than at other sites in the

basin, they did not fall below the Oregon State

standard of 5 mg/L. These decreases in

concentration probably resulted from biochemicaloxygen demand. Comparison of dissolved-oxygen

concentrations in the Willamette River from before

1958 to after 1972 showed a significant increase in

dissolved-oxygen concentrations during the lowstreamflow months of summer. Concentrations of

dissolved oxygen and total dissolved gas were

above saturation levels during high streamflows in

the Willamette River and the lower Columbia River.

The high concentrations of total dissolved gas in the

Columbia River exceeded Oregon and Washington

State standards of 110 percent of saturation and

were caused by spilling water at the Columb

dams.

 Suspended-sediment and suspended-so

concentrations tend to increase with increase

streamflow but were generally very low (less 

mg/L) during most of the year. Among sites

Willamette River generally had higher

concentrations. There were no detectable lon

trends in suspended sediment at the Willame

River and Columbia River at Warrendale site

Suspended-sediment loads at the Beaver Arm

Terminal site in June and July of 1994 were 

than could be accounted for on the basis of l

measured upstream at the Warrendale and

Willamette River sites. The difference in loa

between sites probably results from suspend

sediment that is stored upstream of the Beav

during low-streamflow conditions on the Co

River and then resuspended during the high

streamflows of the snowmelt season. Load

calculations also showed that the Cowlitz Ri

be a source of sediment during high flows, w

other tributaries do not appear to be signific

sources.

Historical data and data for 1994 indica

nutrients have relatively low concentrations 

lower Columbia River Basin. Historically, th

90th-percentile concentrations of unfiltered-

phosphorus and filtered-water nitrite plus nit

ammonia in the basin were in the Willamette 

Basin. When 1994 median concentrations w

ranked from largest to smallest for unfiltered

phosphorus and filtered-water orthophospha

nitrite plus nitrate, sampling sites followed t

order:

Willamette River > Multnomah Channe

Columbia River sites downstream of Willam

River > Columbia River sites upstream of

Willamette River > smaller tributaries.

Concentrations of unfiltered-water pho

in the Willamette River were largest during 

of winter storms from October to February 1

Trend tests showed a significant (ρ < 0.05)

downward trend for unfiltered-water phosph

the Columbia River at Warrendale from 197

1994. Nutrient loads during 1994 in the Wil

River and Columbia River were comparable 

in the low-streamflow year of 1977, which i

consistent with the low precipitation and stre

in 1994. The Willamette River made a signif
134

contribution to the loading of filtered-water nitrite

plus nitrate and unfiltered-water phosphorus in the

Columbia River. In May, the Willamette River

contributed 25 percent of the measured nitrite-plusnitrate load to the Columbia River, while

contributing only 6 percent of the streamflow. In

August, the Willamette River contributed 16 percent

of the phosphorus load to the Columbia River, while

contributing only 8 percent of the streamflow.

Median concentrations of most major ions in

the lower Columbia River Basin in 1994 were

similar to mean concentrations measured in river

systems worldwide. In comparison to historical

data, however, concentrations of major ions

measured in 1994 were lower than historical

measurements and reflect the limited dilution

capacity of the main stem—a result of the low

streamflows in 1994. On the basis of instantaneous

measurements of specific conductance, median

conductance values among main-stem sites were

generally constant, ranging from 149 to 153 μS/cm.

During the fall months, however, a specificconductance gradient was measured among mainstem sites, decreasing by 37 μS/cm from

Warrendale to Beaver Army Terminal, an effect of

the lower specific conductance of water in the

Willamette River and seasonally higher streamflows

entering the main stem from the Willamette River.

The median specific conductance in the Willamette

River was 79 μS/cm, nearly one-half that of the

main stem. The lower conductance waters of the

Willamette River result from lower calcium,

magnesium, and bicarbonate concentrations. Majorion composition along the main stem remained

relatively unchanged, with calcium and magnesium

as the dominant cations and bicarbonate as the

dominant anion.

Median concentrations of trace elements

measured in 1994 were similar to background

concentrations measured worldwide. The

concentrations were also similar to historical

concentrations, except for iron, which in 1994 had a

median concentration (25 μg/L), about one-half that

measured historically. This difference is the result

of a disproportionately high number of sites

sampled historically in the Willamette River Basin.

Arsenic, a human carcinogen, was detected in 15 of

16 samples in the main stem, but was not detected in

the tributary sites. All 15 arsenic detections had

concentrations that exceeded EPA ambient waterquality criteria for the protection of human h

and EPA human-health advisories for drinkin

Chromium was detected in all four main-ste

and most frequently, in the Columbia River 

Hayden Island. None of the concentrations d

however, exceeded water-quality criteria or

guidelines.

Measurements of suspended trace-elem

concentrations (trace-element concentration

associated with the suspended-sediment frac

showed that the suspended form is the domi

transport phase for aluminum, iron, and man

whereas the dissolved form is the dominant t

phase for arsenic, barium, chromium, and co

Because seasonal variations in suspended tra

element concentrations are low, suspended t

element loads are affected primarily by varia

suspended-sediment concentration. Consequ

winter storm-induced high streamflows have

considerably greater loads than low streamfl

which are characteristic of summer and early 

During periods of low streamflow, the Willa

River and Cowlitz River are the largest cont

of suspended trace-elements in the Basin. Du

low-streamflow period, the Willamette River

represents 60 percent of the suspended-silve

the Columbia River at Warrendale, whereas 

percent of the streamflow is represented. On 

basis of tributary loads during summer low-

months, sources of suspended silver, nickel,

aluminum, and antimony exist in the lower

Columbia Basin and the sources of suspende

and arsenic exist outside of the lower basin.

Of the 47 organic compounds analyzed 

study, only 20 were detected. The Willamett

at Portland had the largest number of detecti

all 20 were detected at one time or another a

site. None of the organic compounds measur

exceeded EPA’s ambient water-quality criter

drinking-water guidelines. Atrazine, metolac

and simazine were the three most frequently

detected organic compounds in the lower Co

River Basin. These pesticides all come from

agricultural sources. The largest concentrati

atrazine, metolachlor, and simazine were det

the Willamette River, where they were detect

to 90 percent of the samples collected. The h

concentrations of atrazine in the Willamette 

are associated with the spring application pe
135

fall runoff and can be seen to affect atrazine

concentrations in the main stem and Multnomah

Channel. These seasonal variations are noticeable

also with simazine and metolachlor. The Willamette

River is unquestionably the single largest source of

atrazine to the lower Columbia River.

Fecal-indicator bacteria measurements

exceeded the Washington State standard for fecal

coliform in one instance, in the Cowlitz River.

Additionally, the Washington State standard was

exceeded for several different fecal-indicator

bacteria and in multiple samples in the Willamette

River and Columbia River at Beaver Army

Terminal. Other sites sampled generally had low

concentrations. A review of historical data also

showed consistently low concentrations in the

Columbia River at Warrendale, with higher and

more variable concentrations in the Willamette

River. The source of bacteria in the Willamette

River is likely local runoff from the Portland urban

area.

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implementation of aquatic life criteria for me

Washington, D.C., Office of Science and Tec

May 1992, 24 p.

———1992b, Rules and Regulations: Federal Regis

no. 246, p. 60887.

———1993a, Fish sampling and analysis—Guidan

assessing chemical contamination data for us

advisories: Office of Science and Technolog

Contamination Section, v. 1, 351 p.

———1993b, Drinking water criteria document on 

Human Risk Assessment Branch, Health and

Ecological Criteria Division, EPA Contract N

C8–0033, draft.

———1994a, ARC/INFO coverages derived from U

Geological Survey land use and land cover d

(Internet retrieval): Washington, D.C., scale 

———1994b, Drinking water regulations and health

advisories: Washington, D.C., Office of Wat

November 1994, 11 p.
138

———1995, 304(a) Criteria chart (toxic substance

spreadsheet): Region IV Water Management Division,

January 1995, 13 p.

U.S. Geological Survey, 1972–75, Water resources data,

Oregon, water years 1971–74—pt. 1, Surface water

records: U.S. Geological Survey Water-Data Reports

OR–71–1 to OR–74–1 (published annually).

———1976–80, Water resources data, Oregon, water years

1975–79, v. 1: U.S. Geological Survey Water-Data

Reports OR–75–1 to OR–79–1 (published annually).

———1981, River basins of the United States—The

Columbia: U.S. Geological Survey Popular

Publication 1981–341–618:53, 9 p.

———1981–84, Water resources data, Oregon, water years

1980–83—v. 2, Western Oregon: U.S. Geological

Survey Water-Data Reports OR–80–2 to OR–83–2

(published annually).

———1982, A U.S. Geological Survey data standard—

Codes for the identification of hydrologic units in the

United States and the Caribbean outlying areas: U.S.

Geological Survey Circular 878–A, 115 p.

———1995, Water resources data, Oregon, water year 1994:

U.S. Geological Survey Water-Data Report OR–94–1,

473 p.

Valderrama, J.C., 1981, Simultaneous analysis of total

phosphorus and total nitrogen in natural waters:

Marine Chemistry, v. 10, p. 109–122.

Warner, K., Lafore, B., and Anderson, R., 1992, Portland/

Vancouver toxic waters: Portland, Oregon, ColumbiaWillamette Riverwatch, pamphlet.

Washington Department of Ecology, 1993, Bacteria 

November-December 1992; prepared for the 

Columbia River Bi-state Program: Olympia,

Washington Department of Ecology, 38 p.

Washington State Administrative Code, November 2

Chapter 173–201A, 14 p.

Welsch, E.P., Crock, J.G., and Sanzolone, R., 1990, 

level determination of arsenic and selenium u

continuous-flow hydride generation atomic a

spectrophotometry, in Arbogast, B.F., ed., Q

assurance manual for the Branch of Geochem

Geological Survey Open-File Report 90–668

Wershaw, R.L., Fishman, M.J., Grabbe, R.R., and Lo

eds., 1987, Methods for the determination of 

substances in water and fluvial sediments: U

Geological Survey Techniques of Water-Res

Investigations, book 5, chap. A3, 80 p.

Wilhelms, S.C., and Gulliver, J.S., 1994, Self-aerate

Corps of Engineers spillways: Vicksburg, M

U.S. Army Corps of Engineer Waterways Ex

Station, Technical Report W–94–2, p. 103.

Zaugg, S. D., Sandstrom, M. W., Smith, S. G., and F

K. M., 1995, Methods of analysis by the U. S

Geological Survey National Water-Quality

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C-18 solid-phase extraction and capillary-col

chromatography/mass spectrometry with sele

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Zeif, M., Mitchell, James W., 1976, Contamination 

trace element analysis: New York, John Wile

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139

SUPPLEMENTAL DATA SECTION
140
141

Table 46. Point-source locations and National Pollutant Discharge Elimination System permit levels of effluent discharge, lower Colum

Washington, 1994

[Effluent discharge levels are reported in million gallons per day; STP, sewage-treatment plant; --, not applicable; *, value is based on average dry-weather design flow NA, data is not known or not shown on permit; #1 indicates outfall number; Stormwater, discharge is stormwater, therefore no discharge limits are in effect; avg, averais classified as industrial and, therefore, has limits only on concentrations, not discharge; Misc, miscellaneous; UST, underground storage tank; PAH, polyaromatic h

A = Tetra Tech, Inc., 1992,B = Tim Hilliard, Washington Department of Ecology, unpub. data, 1995,C = Debra Nesbit, Oregon Department of Environmental Quality, written commun., 1995,D = Drew Gilken, Oregon Steel Mills, Inc., oral commun., 1995]

Point-source name Ref. Latitude/ longitude Columbia river mile Receiving water body Tributary river mile Source classification Effluent discharge level Time un

Astoria STP A 461214/

1234621

18 Columbia River -- Domestic 4 *

Camas STP B 453444/

1222317

121.2 Columbia River -- Domestic 2.33 monthly a

Camas WTP B 453618/

1222423

118.1 Lacamas Lake NA Domestic .07 monthly a

Castle Rock STP B 461602/

1225415

68 Cowlitz River NA Domestic .4 monthly a

Cathlamet STP B 461220/

1232315

NA Columbia River -- Domestic .2 monthly a

Cathlamet WTP B 461313/

1232110

NA Columbia River -- Domestic .049 monthly a

Clark Public UtilitiesDistrict (La CenterSTP)

B 455137/

1224007

87 East Fork

of Lewis River

NA Domestic .125 monthly a

Clatskanie STP C 460718/

1231252

47.8 Clatskanie River 1.1 Domestic .50 *

Cowlitz CountyHall of Justice

B 460807/

1225413

68 Cowlitz River NA Domestic .4999 weekly

maximum

Cowlitz WaterPollution Control STP

B 460547/

1225555

67 Columbia River -- Domestic 10 *

Fort Columbia StatePark STP

B 461503/

1235518

8 Columbia River -- Domestic .005 monthly a

Gresham STP A 453326/

1222730

117.5 Columbia River -- Domestic 10 *

Ilwaco STP B 461819/

1240158

3 Columbia River/

Baker Bay

-- Domestic .45 monthly a

Ilwaco WTP B 461853/

1240211

NA Black Lake NA Domestic .045 monthly a
142

Kalama STP B 460032/

1225042

75.5 Columbia River -- Domestic 0.4 monthly a

Kellogg Creek STP C 462625/

1223828

101.5 Willamette River 18.5 Domestic 10 *

Longview STP B 461049/

1230045

56.4 Coal Creek Slough NA Domestic 2.7 monthly a

Longview WTP B 460856/

1225447

68 Cowlitz River NA Domestic .13 monthly a

North Bonneville STP B 453749/

1215811

145 Columbia River -- Domestic .1225 monthly a

Oak Lodge SanitaryDistrict

C 452530/

1223910

101.5 Willamette River 20.1 Domestic 4 *

Portland STP(Columbia Boulevard)

C 453726/

1224132

105.5 Columbia River -- Domestic #1:100

#2:100

**

Portland Tryon CreekSTP

C 452500/

1223945

101.5 Willamette River 19.0 Domestic 8.3 *

Rainier STP A 460537/

1225642

67 Columbia River -- Domestic .5 *

Ridgefield STP B 474915/

1224507

87.5 Lake River NA Domestic .35 monthly a

Riverwood MobileHome Park

A 460403/

1225349

70.6 Columbia River -- Domestic .013 *

St. Helens STP A 455116/

1224714

86 Columbia River -- Domestic NA -- 

Salmon Creek STP(Clark County)

B 454239/

1224530

97.2 Columbia River -- Domestic 3.1 monthly a

Sauvie Island MoorageCompany

C 453852/

1224926

86.3 Multnomah Channel 19.0 Domestic .0075 *

Table 46. Point-source locations and National Pollutant Discharge Elimination System permit levels of effluent discharge, lower Colum

Washington, 1994—Continued

[Effluent discharge levels are reported in million gallons per day; STP, sewage-treatment plant; --, not applicable; *, value is based on average dry-weather design flow NA, data is not known or not shown on permit; #1 indicates outfall number; Stormwater, discharge is stormwater, therefore no discharge limits are in effect; avg, averais classified as industrial and, therefore, has limits only on concentrations, not discharge; Misc, miscellaneous; UST, underground storage tank; PAH, polyaromatic h

A = Tetra Tech, Inc., 1992,B = Tim Hilliard, Washington Department of Ecology, unpub. data, 1995,C = Debra Nesbit, Oregon Department of Environmental Quality, written commun., 1995,D = Drew Gilken, Oregon Steel Mills, Inc., oral commun., 1995]

Point-source name Ref. Latitude/ longitude Columbia river mile Receiving water body Tributary river mile Source classification Effluent discharge level Time un
143

Scappoose STP C 454449/

1225019

86.3 Multnomah Channel 10.5 Domestic 2.015 *

Stella STP B 461126/

1230720

56.4 Columbia River -- Domestic 0.0035 daily

maximum

Three D Corporation C 460840/

1234839

12 Youngs River 2.0 Domestic .62a *

Troutdale STP C 453244/

1222308

120.5 Sandy River 2.3 Domestic 1.6 *

U.S. Army Corps ofEngineers

A 453840/

1215631

146.1 Columbia River -- Domestic .2 *

Vancouver-East STP B 453645/

1223700

110 Columbia River -- Domestic 4 monthly a

Vancouver-West STP B 453810/

1224145

105 Columbia River -- Domestic 15.2 monthly a

Warrenton STP A 461000/

1235517

7 Columbia River -- Domestic .45 *

Washougal STP B 453411/

1222045

NA Columbia River -- Domestic 1.13 monthly a

Woodbrook STP(Cowlitz County)

B 461249/

1225050

68 Ostrander Creek NA Domestic .09 monthly a

Woodland STP B 455904/

1224410

87 Lewis River NA Domestic .48 monthly a

Ash Grove CementCompany

C 453707/

1224656

101.5 Willamette River 3.0 Chemical Stormwater --

BurlingtonEnvironmental

B 453423/

1222008

123.3 Gibbons Creek NA Chemical .003285

.010103

daily averdaily max

Chevron ChemicalCompany

A 455510/

1224852

82 Columbia River -- Chemical 25 daily

maximum

Table 46. Point-source locations and National Pollutant Discharge Elimination System permit levels of effluent discharge, lower ColumWashington, 1994—Continued

[Effluent discharge levels are reported in million gallons per day; STP, sewage-treatment plant; --, not applicable; *, value is based on average dry-weather design flow NA, data is not known or not shown on permit; #1 indicates outfall number; Stormwater, discharge is stormwater, therefore no discharge limits are in effect; avg, averais classified as industrial and, therefore, has limits only on concentrations, not discharge; Misc, miscellaneous; UST, underground storage tank; PAH, polyaromatic h

A = Tetra Tech, Inc., 1992,B = Tim Hilliard, Washington Department of Ecology, unpub. data, 1995,C = Debra Nesbit, Oregon Department of Environmental Quality, written commun., 1995,D = Drew Gilken, Oregon Steel Mills, Inc., oral commun., 1995]

Point-source name Ref. Latitude/ longitude Columbia river mile Receiving water body Tributary river mile Source classification Effluent discharge level Time un
144

Cytec Industries B 460758/

1225530

NA Diking

ImprovementDistrict #1

NA Chemical #1:0.082

.12

#2:0.53

1.7

daily averdaily maxdaily averdaily max

E.F. Houghton andCompany

B 460704/

1225615

NA Drain ditch #3 NA Chemical 0.01 daily

maximum

Elf Atochem NorthAmerica, Inc.

C 453415/

1224430

101.5 Willamette River 7.4 Chemical 37.0 daily

maximum

GATX Terminals B 453809/

1224238

104 Columbia River -- Chemical NA -- 

Hoechst-CelanesCorporation(Virginia Chemicals,Inc.)

B 455943/

1225029

76 Columbia River -- Chemical 1

1.5

daily averdaily max

Kalama Chemical B 460118/

1225135

74 Columbia River -- Chemical .225 daily

maximum

SEH America, Inc. B 453906/

1223324

87.6 Burnt Bridge Creek/

Vancouver STP

NA Chemical 1.2

3.9

daily averdaily max

Union Carbide(Washougal)

B 453419/

1221953

123.3 Gibbons Creek/

Washougal WTP

NA Chemical .06

.085

daily averdaily max

Wacker SiltronicCorporation

C 453436/

1224510

101.5 Willamette River 6.6 Chemical .732b daily

maximum

Allweather WoodTreaters

B 453416/

1222007

123.3 Gibbons Creek NA Wood NA -- 

Astoria PlywoodCompany

A 461123/

1234846

15 Columbia River -- Wood as low as

practicable

-- 

Boise CascadeSt. Helens Veneer Mill

A 455051/

1224807

86 Columbia River -- Wood .5 daily

maximum

Columbia VistaCorporation

B 453510/

1222805

115.6 Columbia River -- Wood permit

canceled

-- 

Table 46. Point-source locations and National Pollutant Discharge Elimination System permit levels of effluent discharge, lower ColumWashington, 1994—Continued

[Effluent discharge levels are reported in million gallons per day; STP, sewage-treatment plant; --, not applicable; *, value is based on average dry-weather design flow NA, data is not known or not shown on permit; #1 indicates outfall number; Stormwater, discharge is stormwater, therefore no discharge limits are in effect; avg, averais classified as industrial and, therefore, has limits only on concentrations, not discharge; Misc, miscellaneous; UST, underground storage tank; PAH, polyaromatic h

A = Tetra Tech, Inc., 1992,B = Tim Hilliard, Washington Department of Ecology, unpub. data, 1995,C = Debra Nesbit, Oregon Department of Environmental Quality, written commun., 1995,D = Drew Gilken, Oregon Steel Mills, Inc., oral commun., 1995]

Point-source name Ref. Latitude/ longitude Columbia river mile Receiving water body Tributary river mile Source classification Effluent discharge level Time un
145

Exterior Wood, Inc. B 453500/

1222100

123.3 Gibbons Creek NA Wood NA -- 

Fort VancouverPlywood Company

B 453744/

1224124

105.2 Columbia River -- Wood NA --

International PaperCompany

B 460615/

1225700

66.5 Columbia River -- Wood 0.25 monthly a

James River SundialChip Reloading Facility

A 453356/

1222547

119 Columbia River -- Wood Industrial -- 

Linnton PlywoodAssociation

C 453557/

1224646

101.5 Willamette River 4.8 Wood NA --

Pacific Wood Treating B 454915/

1224504

87.5 Lake River NA Wood NA -- 

Weyerhauser Company(Wood product)

B 460755/

1225837

NA Diking drainage

ditch #3

NA Wood Industrial -- 

Ameron Pipe Products C 453447/

1223922

101.5 Willamette River 6.5 Misc #1: no dischargec

#2: 0.00005#3: 0.5#4: no discharge

--daily maxdaily max--

Fiberweb North America B 453351/ 1221919 123.3 Gibbons Creek NA Misc .0735 daily maximum

Great Western Malting B 453752/

1224139

105.1 Columbia River -- Misc 9.9 daily

maximum

Holnam, Inc.(Ideal Basic Industries)

B 453737/

1224111

105.5 Columbia River -- Misc .004999 daily

maximum

Lone Star Northwest,Inc. (City Center Plant)

C 453012/

1223952

101.5 Willamette River 13.8 Misc NA --

Table 46. Point-source locations and National Pollutant Discharge Elimination System permit levels of effluent discharge, lower Colum

Washington, 1994—Continued

[Effluent discharge levels are reported in million gallons per day; STP, sewage-treatment plant; --, not applicable; *, value is based on average dry-weather design flow NA, data is not known or not shown on permit; #1 indicates outfall number; Stormwater, discharge is stormwater, therefore no discharge limits are in effect; avg, averais classified as industrial and, therefore, has limits only on concentrations, not discharge; Misc, miscellaneous; UST, underground storage tank; PAH, polyaromatic h

A = Tetra Tech, Inc., 1992,B = Tim Hilliard, Washington Department of Ecology, unpub. data, 1995,C = Debra Nesbit, Oregon Department of Environmental Quality, written commun., 1995,D = Drew Gilken, Oregon Steel Mills, Inc., oral commun., 1995]

Point-source name Ref. Latitude/ longitude Columbia river mile Receiving water body Tributary river mile Source classification Effluent discharge level Time un
146

Northwest PackingCompany

B 453756/

1224123

105.1 Columbia River -- Misc #1: 0.072

.015

#4:0.0115

.072

daily averdaily maxdaily averdaily max

Oregon Museum ofScience and Industry

C 453036/

1224000

101.5 Willamette River 13.5 Misc .575 daily

maximum

Oregon Steel Mills,Inc.

D 453745/

1224705

101.5 Willamette River 1.7 Misc no discharged --

Pendelton WoolenMills

B 453427/

1222104

122.8 Columbia River NA Misc 1

1.25

daily averdaily max

Port of PortlandTerminal 5 (Bulk storage)

C 453742/

1224707

101.5 Willamette River 1.5 Misc NA --

Astoria SeafoodCompany

A 461111/

1235134

12 Columbia River -- Seafood

processing

NA -- 

Bioproducts, Inc. A 461010/

1235451

10.8 Columbia River -- Seafood

processing

.52 monthly a

Chinook PackingCompany

B 461618/

1235648

6 Columbia River/

Baker Bay

-- Seafood

processing

.7 daily

maximum

Jessie’s Ilwaco FishCompany, Inc.

B 461827/

1240214

3 Columbia River/

Baker Bay

-- Seafood

processing

.25 daily

maximum

Ocean Foods of Astoria A 461051/

1235134

12 Columbia River -- Seafood

processing

NA -- 

Pacific Coast SeafoodCompany

A 461000/

1235426

11 Columbia River -- Seafood

processing

NA -- 

Point Adams PackingCompany

A 461152/

1235622

9 Columbia River -- Seafood

processing

NA -- 

Warrenton Deep Sea,Inc.

A 461024/

1235443

7 Columbia River -- Seafood

processing

NA -- 

Table 46. Point-source locations and National Pollutant Discharge Elimination System permit levels of effluent discharge, lower ColumWashington, 1994—Continued

[Effluent discharge levels are reported in million gallons per day; STP, sewage-treatment plant; --, not applicable; *, value is based on average dry-weather design flow NA, data is not known or not shown on permit; #1 indicates outfall number; Stormwater, discharge is stormwater, therefore no discharge limits are in effect; avg, averais classified as industrial and, therefore, has limits only on concentrations, not discharge; Misc, miscellaneous; UST, underground storage tank; PAH, polyaromatic h

A = Tetra Tech, Inc., 1992,B = Tim Hilliard, Washington Department of Ecology, unpub. data, 1995,C = Debra Nesbit, Oregon Department of Environmental Quality, written commun., 1995,D = Drew Gilken, Oregon Steel Mills, Inc., oral commun., 1995]

Point-source name Ref. Latitude/ longitude Columbia river mile Receiving water body Tributary river mile Source classification Effluent discharge level Time un
147

Boise Cascade--Vancouver

B 453736/

1224045

106 Columbia River -- Paper and

pulp

Industrial -- 

James River--Camas B 453506/

1222416

120.1 Columbia River -- Paper and

pulp

Industrial -- 

James River II--Wauna Mill

A 460913/

1232351

42 Columbia River -- Paper and

pulp

Industrial -- 

Longview Fibre--Longview

B 460545/

1225500

67.5 Columbia River -- Paper and

pulp

Industrial -- 

Weyerhauser--Longview

B 460750/

1225927

63.5 Columbia River -- Paper and

pulp

Industrial -- 

ALCOA--Vancouver B 453858/

1224441

103 Columbia River -- Aluminum Industrial -- 

Reynolds Metale B 461049/

1231045

NA Columbia River -- Aluminum NA -- 

Reynolds Metal--Longview

B 460805/

1230010

63 Columbia River -- Aluminum Industrial -- 

Reynolds Metal--Troutdale

A 453324/

1222356

120 Columbia River -- Aluminum Industrial -- 

Ilwaco Boat Hoist B 461822/

1220205

NA Columbia River -- Boat yard .0144 daily

maximum

Port of Ilwaco Boatyard and Marina B 461820/ 1240230 NA Columbia River -- Boat yard .0144 daily maximum 

Port of Portland--Portland Shipyard

C 453400/

1224314

101.5 Willamette River 6.5 Boat yard #1:0.110

#2:0.101#3:0.288

daily maxdaily maxdaily max

Oregon Department ofFish and Wildlife(Prescott)

A 460230/

1225304

73 Columbia River -- Fish hatchery NA -- 

Table 46. Point-source locations and National Pollutant Discharge Elimination System permit levels of effluent discharge, lower Colum

Washington, 1994—Continued

[Effluent discharge levels are reported in million gallons per day; STP, sewage-treatment plant; --, not applicable; *, value is based on average dry-weather design flow NA, data is not known or not shown on permit; #1 indicates outfall number; Stormwater, discharge is stormwater, therefore no discharge limits are in effect; avg, averais classified as industrial and, therefore, has limits only on concentrations, not discharge; Misc, miscellaneous; UST, underground storage tank; PAH, polyaromatic h

A = Tetra Tech, Inc., 1992,B = Tim Hilliard, Washington Department of Ecology, unpub. data, 1995,C = Debra Nesbit, Oregon Department of Environmental Quality, written commun., 1995,D = Drew Gilken, Oregon Steel Mills, Inc., oral commun., 1995]

Point-source name Ref. Latitude/ longitude Columbia river mile Receiving water body Tributary river mile Source classification Effluent discharge level Time un
148

Oregon Department ofFish and Wildlife(Wahkeena)

A 453434/

1220756

134 Columbia River -- Fish hatchery NA -- 

Vancouver TroutHatchery

A 453459/

1223237

113.5 Columbia River -- Fish hatchery 4.05 daily

average

Canonie Environmental Service Corp.(Gould Superfund site)

C 453432/

1224451

101.5 Willamette River 7.0 Remediation .007 daily

maximum

Union Oil Company ofCalifornia--WillbridgeBulk Terminal

C 453420/

1224408

101.5 Willamette River 5.7 Remediation .144f daily

maximum

Western Station Corp.UST #606

B 454205/

1224005

68 Salmon Creek NA Remediation .003

.003

dail y averdaily max

Chevron USA, Inc.--Willbridge Distribution Center

C 453357/

1224415

101.5 Willamette River 7.9 Tank farm NA --

Koppers Industry, Inc. C 453438/

1224532

101.5 Willamette River 6.5 Tank farm .006g daily

maximum

Beaver GeneratingPlant

A 461026/

1231031

54 Columbia River -- Power

generating

1.44 daily

maximum

Trojan Nuclear PowerPlant

A 460226/

1225256

72.5 Columbia River -- Power

generating

64.3 daily

maximum

aValue is from renewal application dated 07/07/1992.bValue is from renewal application dated 11/12/1991.cNo discharge unless discharge is greater that the recycler’s capacity of 0.07 mgd.dNo discharge unless discharge is greater than the recycler’s capacity. Permit states the limit is 5.76 mgd.eBicc Cable Corporation doing-business-as Cablec Utility Cable Company.fPermittee has special permit for discharge of treated groundwater from petroleum hydrocarbon remediation system.gValue is from permit expiring 07/31/1991.

Table 46. Point-source locations and National Pollutant Discharge Elimination System permit levels of effluent discharge, lower Colum

Washington, 1994—Continued

[Effluent discharge levels are reported in million gallons per day; STP, sewage-treatment plant; --, not applicable; *, value is based on average dry-weather design flow NA, data is not known or not shown on permit; #1 indicates outfall number; Stormwater, discharge is stormwater, therefore no discharge limits are in effect; avg, averais classified as industrial and, therefore, has limits only on concentrations, not discharge; Misc, miscellaneous; UST, underground storage tank; PAH, polyaromatic h

A = Tetra Tech, Inc., 1992,B = Tim Hilliard, Washington Department of Ecology, unpub. data, 1995,C = Debra Nesbit, Oregon Department of Environmental Quality, written commun., 1995,D = Drew Gilken, Oregon Steel Mills, Inc., oral commun., 1995]

Point-source name Ref. Latitude/ longitude Columbia river mile Receiving water body Tributary river mile Source classification Effluent discharge level Time un
149

Table 47. Summary of trace-element concentrations that exceed screening values derived from water-quality guidelines, lower CoWashington, 1994[Only detectable concentrations were evaluated against water-quality guidelines; percentages were calculated using all measurements (censored and detected) foliter; see table 7 for full site names; --, criteria do not exist to compare values to]

Site name

Total

number

of

samples

Number of samples that exceed screen

Ambient water-quality criteria 

Aquatic life Human health

Acute Chronic 

Aquatic

organisms

and water

Aquatic

organisms

only

Arsenic:

Ambient water-quality criteriaa:

Aquatic life:

Acute: 1-hour average 360 μg/L once in three years

Chronic: 4-day average 190 μg/L once in three years

Human health:

Consumption of aquatic organisms and water: 0.18 μg/L

Consumption of aquatic organisms only: 1.4 μg/L

Note: Human-health guidelines are based on a slope factor (q1*) of 1.75 (milligrams per kilogram per day)-1, a bioconcentration factor of 

time risk of cancer equivalent to 1 in 100,000, a consumption rate of fish of 6.5 grams per day (about one six-ounce fillet per month--sumption rate of water of 2 liters per day, a body weight of 70 kilograms (154 pounds), and a life expectancy of 70 years.

Drinking-water guidelinesb:

Regulation: 50.0 μg/L (Maximum Contaminant Level)

Human-health advisory: 0.2 μg/L Risk-specific dose

Note: Human-health advisory is based on a slope factor (q1*) of 1.75 (milligrams per kilogram per day)-1, a lifetime risk of cancer equ

sumption rate of water of 2 liters per day, a body weight of 70 kilograms (154 pounds), and a life expectancy of 70 years.

Columbia River at Warrendale 4 0 0 4 0 Columbia River at Hayden Island 4 0 0 4 0 Multnomah Channel near mouth 4 0 0 1 0 Columbia River near Columbia City 4 0 0 4 0 Columbia River at Beaver Army Terminal 4 0 0 3 0 

Percentage of samples that exceed screening values 0 0 38 0 

Iron:

Ambient water-quality criteria1:

Aquatic life:

Chronic: 1,000 μg/L

Human health:

Consumption of aquatic organisms and water: 300 μg/L

Willamette River 25 -- 0 1 -- 

Percentage of samples that exceed screening values -- 0 1 -- 
150

Site name

Total

number

of

samples

Number of samples that exceed screen

Ambient water-quality criteria 

Aquatic life Human health

Acute Chronic 

Aquatic

organisms

and water

Aquatic

organisms

only

Mercury:

Ambient water-quality criteria1:

Aquatic life:

Acute: 1-hour average 2.4 μg/L

Chronic: 4-day average 0.012 μg/L (If exceeded, USEPA recommends that edible portions of fish be tested relative to FDA action lev

Human health:

Consumption of aquatic organisms and water: 0.14 μg/L

Consumption of aquatic organisms only: 0.15 μg/L

Note: Human-health guidelines are based on a reference dose (RfD) of 6 x 10-5 milligrams per kilogram per day, a bioconcentration fac

gram, a consumption rate of fish of 6.5 grams per day (about one six-ounce filet per month--the national average), a consumption rata body weight of 70 kilograms (154 pounds), and a life expectancy of 70 years.

Drinking-water guidelines2:

Regulation: 2 μg/L (Maximum Contaminant Level)Human-health advisory: 0.4 μg/L Lifetime-health advisory (relative-source contribution from drinking water is assumed to be 20 perceNote: Human-health advisory is based on a reference dose (RfD) of 6 x 10-5 milligrams per kilogram per day, a consumption rate of wa

weight of 70 kilograms (154 pounds), and a life expectancy of 70 years.

Willamette River at Portland 5 0 1 1 1 Multnomah Channel near mouth 4 0 1 0 0 Columbia River at Beaver Army Terminal 4 1 1 1 1 

Percentage of samples that exceed screening values 2 7 5 5 

aU.S. Environmental Protection Agency (1995).bU.S. Environmental Protection Agency (1994).

Table 47. Summary of trace-element concentrations that exceed screening values derived from water-quality guidelines, lower CoWashington, 1994—Continued[Only detectable concentrations were evaluated against water-quality guidelines; percentages were calculated using all measurements (censored and detected) foliter; see table 7 for full site names; --, criteria do not exist to compare values to]
151

Table 48. Summary of physical and microbiological measurements that exceed screening values derived from a

water-quality criteria, lower Columbia River Basin, Oregon and Washington, 1994

Site name Total number

of samples

Number of samples 

exceed screening v

Dissolved oxygen:

Oregona

: Columbia River and tributaries shall exceed 90-percent saturation (except for lower Willamette River and

Multnomah Channel, where DO shall not be less than 5 milligrams per liter)

Washingtonb

: Columbia River shall exceed 90-percent saturation; tributaries shall not be less than 8 milligrams per liter

a

State of Oregon (1994).

bWashington State Administrative Code (1992).

Sandy River near Troutdale, Oregon 18 1

Percentage of samples that exceed screening value 6

Fecal coliform bacteria:

Oregon1

: Not to exceed 400 colonies per 100 milliliters of water

Washington2

: Not to exceed 200 colonies per 100 milliliters of water

Cowlitz River at Kelso, Washington

(Washington Department of Ecology sampling)

12 1

Percentage of samples that exceed screening value 8

pH:

Oregon1

 and Washington2: Not to fall outside the range: 6.5 - 8.5

Columbia River at river mile 102, downstream of Hayden Island, Oregon 14 2

Columbia River at Beaver Army Terminal near Quincy, Oregon 18 1

Percentage of samples that exceed screening value 9

Temperature:

Washington2

: Columbia River shall not exceed 20 degrees Celsius due to human activities

Columbia River at Warrendale, Oregon 11 2

Columbia River at river mile 102, downstream of Hayden Island, Oregon 14 2

Columbia River near Columbia City, Oregon 12 2

Columbia River at Beaver Army Terminal near Quincy, Oregon 16 2

Percentage of samples that exceed screening value 15

Total dissolved gas:

Oregon1 and Washington2: Columbia River shall not exceed 110-percent saturation

Columbia River at Warrendale, Oregon 3 1

Columbia River at river mile 102, downstream of Hayden Island, Oregon 3 1

Columbia River near Columbia City, Oregon 2 1

Columbia River at Beaver Army Terminal near Quincy, Oregon 6 1

Percentage of samples that exceed screening value 29
152

Table 49. Summary of constituent concentrations in filtered water that did not exceed screening values derived from w

guidelines, lower Columbia River Basin, Oregon and Washington, 1994

[The term “filtered water” is an operational definition referring to the chemical analysis of that portion of a water-suspended sediment sample that 

a nominal 0.7-micrometer filter for organic compounds and 0.45-micrometer filter for inorganic constituents; for reference purposes, the aquatic-l

listed below are based on a hardness of 50 milligrams per liter as calcium carbonate; the ambient hardness was used to calculate screening values 

in the evaluation of detected concentrations; screening values are based on a risk level of 10-5 where applicable; mg/L, milligrams per liter; MCL

contaminant level; MCLG, maximum contaminant level goal; μg/L, micrograms per liter; RSD, risk-specific dose (carcinogen); see table 9 for Che

Services registry numbers for organic compounds]

Constituent Water-quality screening values Total number of samples

Nutrients

Ammonia Ambient water-quality criteriona,b:

Aquatic life:

 pH and temperature dependent

93

Nitrite Drinking-water guidelinec

:

Regulation: 1 mg/L (MCL and MCLG)

93

Nitrite plus nitrate Drinking-water guideline3:

Regulation: 10 mg/L (MCL and MCLG)

93

Major ions

Fluoride Drinking-water guideline3:

Regulation: 400 μg/L (under review)

95

Trace elements

Antimony Ambient water-quality criteria1:

Human health:

Consumption of aquatic organisms and water: 140 μg/L

Consumption of aquatic organisms only: 43,000 μg/L

Drinking-water guidelines1:

Regulation: 6 μg/L (MCL and MCLG)

Human-health advisories:

Child, long term: 10 μg/L

Adult, lifetime: 3 μg/L

42

Barium Ambient water-quality criterion1:

Human health:

Consumption of aquatic organisms and water: 20,000 μg/L

Drinking-water guidelines3:

Regulation: 2,000 ug/L (MCL)

Human-health advisory:

Adult, lifetime: 2,000 μg/L

50

Beryllium Drinking-water guidelines3:

Regulation: 4 μg/L (MCL and MCLG)

Human-health advisory:

Child, long term: 4,000 μg/L

42

Cadmium Ambient water-quality criteria1:

Aquatic life:

Acute: 1.79 μg/L

Chronic: 0.66 μg/L

Drinking-water guideline3

:

Regulation: 5 μg/L (MCL and MCLG)

42

Chromium Ambient water-quality criteria1

:

Aquatic life:

Acute: 16 μg/L

Chronic: 11 μg/L

Drinking-water guideline3:

Regulation: 100 μg/L (MCL and MCLG)

42
153

Trace elements–Continued

Copper Ambient water-quality criteria1:

Aquatic life:

Acute: 9.22 μg/L

Chronic: 6.54 μg/L

Human health

Consumption of aquatic organisms and water: 1,3000 μg/L

Drinking-water guideline3:

Regulation: 1,300 μg/L (proposed MCL)

42

Lead Ambient water-quality criteria1

:

Aquatic life:

Acute: 33.78 μg/L

Chronic: 1.32 μg/L

Human health:

Consumption of aquatic organisms and water: 50 μg/L

42

Molybdenum Drinking-water guidelines3:

Human-health advisories:

Child, long term: 10 μg/L

Adult, lifetime: 40 μg/L

Nickel Ambient water-quality criteria1:

Aquatic life:

Acute: 789 μg/L

Chronic: 87.71 μg/L

Human health:

Consumption of aquatic organisms and water: 610 μg/L

Consumption of aquatic organisms only: 4,600 μg/L

Drinking-water guidelines3:

Regulation: 100 μg/L (MCL and MCLG)

Human-health advisories:

Child, long term: 500 μg/L

Adult, lifetime: 100 μg/L

50

Selenium Ambient water-quality criteria1:

Aquatic life:

Acute: 20 μg/L

Chronic: 5 μg/L

Drinking-water guideline3:

Regulation: 50 μg/L (MCL)

50

Silver Ambient water-quality criterion1

:

Aquatic life:

Acute: 1.23 μg/L

Drinking-water guidelines3

:

Human-health advisories (draft):

Child, long term: 200 μg/L

Adult, lifetime: 100 μg/L

50

Uranium Drinking-water guideline3

:

Regulation (proposed): 20 μg/L (MCL)

43

Zinc Ambient water-quality criteria1

:

Aquatic life:

Acute: 65.04 μg/L

Chronic: 58.91 μg/L

42

Table 49. Summary of constituent concentrations in filtered water that did not exceed screening values derived from w

guidelines, lower Columbia River Basin, Oregon and Washington, 1994—Continued

[The term “filtered water” is an operational definition referring to the chemical analysis of that portion of a water-suspended sediment sample that 

a nominal 0.7-micrometer filter for organic compounds and 0.45-micrometer filter for inorganic constituents; for reference purposes, the aquatic-l

listed below are based on a hardness of 50 milligrams per liter as calcium carbonate; the ambient hardness was used to calculate screening values 

in the evaluation of detected concentrations; screening values are based on a risk level of 10-5 where applicable; mg/L, milligrams per liter; MCL

contaminant level; MCLG, maximum contaminant level goal; μg/L, micrograms per liter; RSD, risk-specific dose (carcinogen); see table 9 for Che

Services registry numbers for organic compounds]

Constituent Water-quality screening values Total number of samples
154

Organic compounds

Alachlor Drinking-water guidelines3:

Regulation: 2 μg/L (MCL)

Human-health advisory: 4 μg/L RSD

47

Atrazine Drinking-water guidelines3:

Regulation: 3 μg/L (MCL)

Human-health advisories:

Child, long term: 50 μg/L

Adult, lifetime: 3 μg/L (under review)

47

Butylate Drinking-water guidelines3:

Human-health advisories:

Child, long term: 1,000 μg/L

Adult, lifetime: 350 μg/L

47

Carbaryl Drinking-water guidelines3:

Human-health advisories:

Child, long term: 1,000 μg/L

Adult, lifetime: 700 μg/L

47

Carbofuran Drinking-water guidelines3:

Regulation: 40 μg/L (MCL)

Human-health advisories:

Child, long term: 50 μg/L

Adult, lifetime: 40 μg/L

47

Chlorpyrifos Ambient water-quality criteria1:

Aquatic life:

Acute: 0.083 μg/L

Chronic: 0.041μg/L

Drinking-water guidelines3:

Human-health advisories:

Child, long term: 30 μg/L

Adult, lifetime: 20 μg/L

47

Cyanazine Drinking-water guidelines3:

Regulation: 1 μg/L (tentative MCLG)

Human-health advisories (draft):

Child, long term: 20 μg/L

Adult, lifetime:1 μg/L

47

DCPA Drinking-water guidelines3:

Human-health advisories:

Child, long term: 5,000 μg/L

Adult, lifetime: 4,000 μg/L

47

Diazinon Drinking-water guidelines3:

Human-health advisories:

Child, long term: 5 μg/L

Adult, lifetime: 0.6 μg/L

47

Dieldrin Ambient water-quality criteria1:

Aquatic life:

Acute: 2.5 μg/L

Chronic: 0.0019 μg/L

47

Table 49. Summary of constituent concentrations in filtered water that did not exceed screening values derived from w

guidelines, lower Columbia River Basin, Oregon and Washington, 1994—Continued

[The term “filtered water” is an operational definition referring to the chemical analysis of that portion of a water-suspended sediment sample that 

a nominal 0.7-micrometer filter for organic compounds and 0.45-micrometer filter for inorganic constituents; for reference purposes, the aquatic-l

listed below are based on a hardness of 50 milligrams per liter as calcium carbonate; the ambient hardness was used to calculate screening values 

in the evaluation of detected concentrations; screening values are based on a risk level of 10-5 where applicable; mg/L, milligrams per liter; MCL

contaminant level; MCLG, maximum contaminant level goal; μg/L, micrograms per liter; RSD, risk-specific dose (carcinogen); see table 9 for Che

Services registry numbers for organic compounds]

Constituent Water-quality screening values Total number of samples
155

Organic compounds–Continued

Dieldrin–Continued Human health:

Consumption of aquatic organisms and water: 0.0014 μg/L

Consumption of aquatic organisms only: 0.0014 μg/L

Drinking-water guidelines3:

Human-health advisories:

Child, long term: 0.5 μg/L

RSD: 0.02 μg/L

Disulfoton Drinking-water guidelines3:

Human-health advisories:

Child, long term: 3 μg/L

Adult, lifetime: 0.3 μg/L

47

Fonofos Drinking-water guidelines3:

Human-health advisories:

Child, long term: 20 μg/L

Adult, lifetime: 10 μg/L

47

alpha-HCH Ambient water-quality criteria1:

Human health:

Consumption of aquatic organisms and water: 0.039 μg/L

Consumption of aquatic organisms only: 0.13 μg/L

47

gamma-HCH

(lindane)

Ambient water-quality criteria1:

Aquatic life:

Acute: 2 μg/L

Chronic: 0.08 μg/L

Human health:

Consumption of aquatic organisms and water: 0.19 μg/L

Consumption of aquatic organisms only: 0.63 μg/L

Drinking-water guidelines3:

Regulation: 0.2 μg/L (MCL and MCLG)

Human-health advisories:

Child, long term: 30 μg/L

Adult, lifetime: 0.2 μg/L

47

Malathion Ambient water-quality criterion1:

Aquatic life:

Chronic: 0.1 μg/L

Drinking-water guidelines3:

Human-health advisories:

Child, long term: 200 μg/L

Adult, lifetime: 200 μg/L

47

Methyl parathion Drinking-water guidelines3

:

Human-health advisories:

Child, long term: 30 μg/L

Adult, lifetime: 2 μg/L

47

Metolachlor Drinking-water guidelines3:

Human-health advisories:

Child, long term: 1,000 μg/L

Adult, lifetime: 70 μg/L

47

Table 49. Summary of constituent concentrations in filtered water that did not exceed screening values derived from w

guidelines, lower Columbia River Basin, Oregon and Washington, 1994—Continued

[The term “filtered water” is an operational definition referring to the chemical analysis of that portion of a water-suspended sediment sample that 

a nominal 0.7-micrometer filter for organic compounds and 0.45-micrometer filter for inorganic constituents; for reference purposes, the aquatic-l

listed below are based on a hardness of 50 milligrams per liter as calcium carbonate; the ambient hardness was used to calculate screening values 

in the evaluation of detected concentrations; screening values are based on a risk level of 10-5 where applicable; mg/L, milligrams per liter; MCL

contaminant level; MCLG, maximum contaminant level goal; μg/L, micrograms per liter; RSD, risk-specific dose (carcinogen); see table 9 for Che

Services registry numbers for organic compounds]

Constituent Water-quality screening values Total number of samples
156

Organic compounds–Continued

Metribuzin Drinking-water guidelines3:

Human-health advisories:

Child, long term: 300 μg/L

Adult, lifetime: 200 μg/L

47

Parathion Ambient water-quality criteria1:

Aquatic life:

Acute: 0.065 μg/L

Chronic: 0.013 μg/L

47

Prometon Drinking-water guidelines3:

Human-health advisories:

Child, long term: 200 μg/L

Adult, lifetime: 100 μg/L (under review)

47

Pronamide Drinking-water guidelines3:

Human-health advisories:

Child, long term: 800 μg/L

Adult, lifetime: 50 μg/L

47

Propachlor Drinking-water guidelines3:

Human-health advisories:

Child, long term: 100 μg/L

Adult, lifetime: 90 μg/L

47

Simazine Drinking-water guidelines3:

Regulation: 4 μg/L (MCL and MCLG)

Human-health advisories:

Child, long term: 70 μg/L

Adult, lifetime: 4 μg/L

47

Tebuthiuron Drinking-water guidelines3:

Human-health advisories:

Child, long term: 700 μg/L

Adult, lifetime: 500 μg/L

47

Terbacil Drinking-water guidelines3:

Human-health advisories:

Child, long term: 300 μg/L

Adult, lifetime: 90 μg/L

47

Terbufos Drinking-water guidelines3:

Human-health advisories:

Child, long term: 1 μg/L

Adult, lifetime: 0.9 μg/L

47

Trifluralin Drinking-water guidelines3:

Human-health advisories:

Child, long term: 80 μg/L

Adult, lifetime: 5 μg/L

RSD: 50 μg/L

47

a

U.S. Environmental Protection Agency, 1995.

b

U.S. Environmental Protection Agency, 1976.

c

U.S. Environmental Protection Agency, 1994b.

Table 49. Summary of constituent concentrations in filtered water that did not exceed screening values derived from w

guidelines, lower Columbia River Basin, Oregon and Washington, 1994—Continued

[The term “filtered water” is an operational definition referring to the chemical analysis of that portion of a water-suspended sediment sample that 

a nominal 0.7-micrometer filter for organic compounds and 0.45-micrometer filter for inorganic constituents; for reference purposes, the aquatic-l

listed below are based on a hardness of 50 milligrams per liter as calcium carbonate; the ambient hardness was used to calculate screening values 

in the evaluation of detected concentrations; screening values are based on a risk level of 10-5 where applicable; mg/L, milligrams per liter; MCL

contaminant level; MCLG, maximum contaminant level goal; μg/L, micrograms per liter; RSD, risk-specific dose (carcinogen); see table 9 for Che

Services registry numbers for organic compounds]

Constituent Water-quality screening values Total number of samples
157

Table 50. Summary of trends in selected water-quality constituents, lower Columbia River Basin, Oregon, 1973-1995[The term “filtered water” is an operational definition referring to the chemical analysis of that portion of a water-suspended sediment sample that passes through a nomthe term “unfiltered water” refers to the chemical analysis of a water sample that has not been filtered or centrifuged, nor in any way altered from the original matrion a quarterly season; Warrendale, Columbia River at Warrendale, Oregon; Willamette River, Willamette River at Portland, Oregon; *, not enough data for trend te

Non-flow adjusted 

Station

number Station name Period of record

Number of

observations

Probability

level

Trend,

units per

year

Trend,

percent of

median per

year

Median,

units

Water temperature (in degrees Celsius)

14128910 Warrendale 04/23/74-12/20/94 77 0.026 0.073 0.6 11.9 14211720 Willamette River 10/25/74-01/24/95 79 .000 .140 1.1 12.5 

Suspended sediment concentration (in milligrams per liter)

14128910 Warrendale 03/06/73-12/20/94 79 .105 -.143 -1.3 11.0 14211720 Willamette River 10/25/74-12/02/94 79a

aThe number of observations for the non-flow-adjusted suspended-sediment trend was 112, based on a bimonthly season.

.119 -.118 -1.0 11.5 

Ammonia in filtered water as nitrogen (in milligrams per liter)

14128910 Warrendale 10/24/79-12/20/94 54 * * * * 14211720 Willamette River 10/24/79-01/24/95 59 * * * * 

Nitrite plus nitrate in filtered water as nitrogen (in milligrams per liter)

14128910 Warrendale 09/13/79-12/20/94 65 * * * * 14211720 Willamette 09/17/79-01/24/95 59 * * * * 

Orthophosphate in filtered water as phosphorus (in milligrams per liter)

14128910 Warrendale 10/15/81-12/20/94 47 * * * * 14211720 Willamette River 10/16/81-01/24/95 51 * * * * 

Phosphorus in unfiltered water as phosphorus (in milligrams per liter)

14128910 Warrendale 03/06/73-12/20/94 80b

bA data anomaly of 0.55 milligrams per liter was removed from analysis.

.001 -.001 -2.8 .04 

14211720 Willamette River 10/25/74-01/24/95 79 .749 no trend no trend .08 

Specific conductance (in microsiemens per centimeter at 25 degrees Celsius)

14128910 Warrendale 03/06/73-12/20/94 81 .019 -.74 -.5 160 14211720 Willamette River 10/25/74-01/24/95 79 .141 .33 .5 72 

Total dissolved solids (in milligrams per liter)

14128910 Warrendale 03/06/73-12/20/94 80 .001 -.61 -.6 96 14211720 Willamette River 10/25/74-01/24/95 77 .757 no trend no trend 55