U.S. Department of the Interior

U.S. Geological Survey

Prepared in cooperation with

U.S. Environmental Protection Agency

Concentrations and Loads of Cadmium, Lea

Zinc, and Nutrients Measured During the 199

Water Year Within the Spokane River Basin, 

Idaho and Washington

Open-File Report 00–441

This report has not been reviewed for conformity with U.S. Geological Survey editorial standards. 
Concentrations and Loads of Cadmium, Lead

Zinc, and Nutrients Measured During the 1999 

Water Year Within the Spokane River Basin, 

Idaho and Washington

By Paul F. Woods

Open-File Report 00–441

Prepared in cooperation with

U.S. Environmental Protection Agency

Boise, Idaho

2001
U.S. DEPARTMENT OF THE INTERIOR

GALE A. NORTON, Secretary

U.S. GEOLOGICAL SURVEY

Charles G. Groat, Director 

Any use of firm, trade, and brand names in this report is for

identification purposes only and does not constitute 

endorsement by the U.S. Government.

Additional information can be obtained from:

District Chief

U.S. Geological Survey

230 Collins Road

Boise, ID 83702-4520

http://idaho.usgs.gov

This report is available online in PDF for

http://idaho.usgs.gov/public/reports.html

and can be viewed using Adobe Acrobat 

Reader. The URL is:
iii

CONTENTS

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

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

Approach ..........................................................................................................................................................

Locations of data-collection stations .........................................................................................................

Collection and computation of discharge data...........................................................................................

Collection and analysis of water-quality data............................................................................................

Calculation of loads ...................................................................................................................................

Annual loads and concentrations, 1999 water year..........................................................................................

Hydrologic loads........................................................................................................................................

Cadmium loads ..........................................................................................................................................

Dissolved.............................................................................................................................................

Whole-water recoverable ....................................................................................................................

Cadmium concentrations ...........................................................................................................................

Lead loads..................................................................................................................................................

Dissolved.............................................................................................................................................

Whole-water recoverable ....................................................................................................................

Lead concentrations ...................................................................................................................................

Zinc loads...................................................................................................................................................

Dissolved.............................................................................................................................................

Whole-water recoverable ....................................................................................................................

Zinc concentrations....................................................................................................................................

Nutrient loads.............................................................................................................................................

Nitrogen...............................................................................................................................................

Phosphorus ..........................................................................................................................................

Comparison of nutrient loads in calendar year 1991 and water year 1999.........................................

Nutrient concentrations..............................................................................................................................

References cited ...............................................................................................................................................

FIGURE

1. Map showing locations of 29 water-quality stations monitored during the 1999 water year within 

the Spokane River Basin, Idaho and Washington ..................................................................................

TABLES

1. U.S. Geological Survey station numbers and names for 29 water-quality stations monitored during 

the 1999 water year within the Spokane River Basin, Idaho and Washington .....................................

2. Mean daily discharge and annual loads of dissolved and whole-water recoverable cadmium, lead, 

and zinc measured during the 1999 water year at 24 water-quality stations within the Spokane River 

Basin, Idaho and Washington.................................................................................................................

3. Mean, flow-weighted concentrations of dissolved and whole-water recoverable cadmium, lead, and 

zinc measured during the 1999 water year at 24 water-quality stations within the Spokane River 

Basin, Idaho and Washington.................................................................................................................
iv

4. Mean daily discharge and annual loads of nitrogen and phosphorus measured during the 1999 water 

year at nine water-quality stations within the Spokane River Basin, Idaho and Washington................

5. Mean, flow-weighted concentrations of nitrogen and phosphorus measured during the 1999 water 

year at nine water-quality stations within the Spokane River Basin, Idaho and Washington................

CONVERSION FACTORS AND OTHER ABBREVIATED UNITS

Multiply By To obtain

cubic foot per second (ft3/s) 0.02832 cubic meter per second

mile (mi) 1.609 kilometer

pound (lb) 0.4536 kilogram

pound per day (lb/d) 0.4536 kilogram per day

square mile (mi2) 2.590 square kilometer

Temperature in degrees Celsius (°C) can be converted to degrees Fahrenheit (°F) as follows:

° F=(1.8) (°C)+32

Other abbreviated units:

DEG C. . . . . . . . . . . . . degrees Celsius

μg/L, UG/L . . . . . . . . . microgram per liter

μm . . . . . . . . . . . . . . . . micrometer

mg/L, MG/L . . . . . . . . milligram per liter

mL, ML. . . . . . . . . . . . milliliter
1

ABSTRACT

The Remedial Investigation/Feasibility Study 

conducted by the U.S. Environmental Protection 

Agency within the Spokane River Basin of northern Idaho and eastern Washington included extensive data-collection activities to determine the 

nature and extent of trace-element contamination 

within the basin. The U.S. Geological Survey 

designed and operated a streamflow and waterquality monitoring network in the basin during 

the 1999 water year (October 1, 1998, through 

September 30, 1999) in support of this Remedial 

Investigation/Feasibility Study. The objective for 

the network was to quantify the absolute and relative magnitude of hydrologic, trace-element, and 

nutrient loads transported by numerous stream 

reaches within the Spokane River Basin. Of the 

29 water-quality stations in the network, 19 were 

in the Coeur d’Alene River Basin, 2 were in the St. 

Joe River Basin, and the remaining 8 were on the 

Spokane River downstream from Coeur d’Alene 

Lake. All stations were sampled for whole-water 

recoverable and dissolved concentrations of cadmium, lead, and zinc. Nitrogen and phosphorus 

concentrations were sampled at nine stations to 

determine loads of nutrients into and out of Coeur 

d’Alene Lake and transported down the Spokane 

River into the Columbia River. 

Mean daily discharge during the 1999 water 

year was about 120 percent of the long-term average. Trace-element loads to the Columbia River 

were calculated for the basin’s terminal station, 

Spokane River at Long Lake. For whole-water 

recoverable cadmium, 2,110 pounds, 92 percent 

of which was dissolved, was delivered to th

Columbia River. The Columbia River receiv

25,000 pounds of whole-water recoverable 

29 percent of which was dissolved, from th

kane River Basin. The largest trace-element 

delivered to the Columbia River by the Spo

River was 764,000 pounds of whole-water r

erable zinc, 76 percent of which was dissolv

The primary source of trace-element lo

the Spokane River Basin was the Coeur d’A

River Basin. The South Fork Coeur d’Alene 

was the largest source of dissolved and who

water recoverable loads of cadmium and zin

contrast, the main stem of the Coeur d’Alene 

was the largest source of dissolved and who

water recoverable loads of lead. Within the 

Fork, substantial increases in dissolved load

cadmium, lead, and zinc were detected in ex

of those measured by the monitoring netwo

stations upstream from the terminal station, 

Fork Coeur d’Alene River near Pinehurst. M

of the added load was attributed to inflow o

element-contaminated ground water. Simila

creases in whole-water recoverable loads of 

mium, lead, and zinc were detected in the S

Fork in excess of measured loads; these we

attributed largely to erosion and transport o

ment-associated trace elements during incre

stream discharge events.

Coeur d’Alene Lake received nearly a

trace-element loads from the Coeur d’Alene 

The lake retained the majority of the dissolv

whole-water recoverable loads of lead inpu

but retained almost none of its dissolved an

whole-water recoverable loads of zinc. Abo

Concentrations and Loads of Cadmium, Lead

Zinc, and Nutrients Measured During the 1999 

Water Year Within the Spokane River Basin, 

Idaho and Washington

By Paul F. Woods
2

half of the dissolved and whole-water recoverable 

loads of cadmium was retained in the lake.

Within the Spokane River Basin, the largest 

loads of total nitrogen, 13,000,000 pounds, and 

total phosphorus, 677,000 pounds, were measured 

at Spokane River at Long Lake, the station closest 

to the Columbia River. At Coeur d’Alene Lake, total 

nitrogen loads input to the lake from the Coeur 

d’Alene and St. Joe Rivers totaled 1,890,000 

pounds; the lake discharged 2,430,000 pounds. The 

lake received 253,000 pounds of total phosphorus 

and discharged 187,000 pounds; thus, 66,000 

pounds was retained by the lake.

INTRODUCTION

Mining and ore-processing activities conducted 

over the past 100 years in the South Fork Coeur 

d’Alene River Basin have produced extensive deposits 

of trace-element-contaminated sediments throughout 

the South Fork Coeur d’Alene River valley and its 

tributaries, the channel and flood plain of the mainstem Coeur d’Alene River, and the lakebed of Coeur 

d’Alene Lake. Snowmelt runoff and occasional floods 

continue to transport and redistribute trace-elementcontaminated sediments throughout the 6,680-mi2 Spokane River Basin of northern Idaho and eastern Washington (fig. 1, back of report). 

The U.S. Environmental Protection Agency 

(EPA) recently initiated a Remedial Investigation/

Feasibility Study (RI/FS) of the Spokane River Basin 

under the authority of the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 

(CERCLA), which requires EPA to evaluate contaminant release, fate, and transport. The Remedial Investigation phase involves data collection to characterize 

site conditions, development of conceptual models, 

determination of the nature and extent of trace-element 

contamination, and risk assessment for human health 

and the environment. The development and evaluation 

of remedial action alternatives are the focus of the Feasibility Study. In March 1998, the EPA asked the U.S. 

Geological Survey (USGS) to identify hydrologic and 

water-quality studies the USGS might perform in support of the RI/FS of the Spokane River Basin. The 

study described in this report was conducted by the 

USGS as a combination of Task 2 (streamflow and 

water-quality monitoring) and two amendments 

2 (streamflow and water-quality monitoring on 

Spokane River in Washington and additional ge

chemical analytes and a fourth sampling trip fo

segment 3 stations) under Interagency Agreem

DW14957278–01–1 and DW14957278–01–2, 

tively, with EPA.

The purpose of this report is to quantify th

absolute and relative magnitudes of hydrologic, 

element, and nutrient loads transported by num

stream reaches within the Spokane River Basin

scope of activities included collection and analy

discharge and water-quality samples during the 

water year (October 1, 1998, through Septembe

1999), followed by computation of hydrologic, 

element, and nutrient loads. The geographic dis

tion of stations was as follows: Coeur d’Alene R

Basin, 19; St. Joe River Basin, 2; Spokane Rive

stream from Coeur d’Alene Lake, 8. This distri

of stations enabled calculation of hydrologic, tr

ment, and nutrient loads into and out of Coeur d

and Long Lakes; additionally, the loads of trace 

ments and nutrients delivered to Lake Roosevel

the Columbia River, by the Spokane River Basi

quantified. 

APPROACH

Locations of Data-Collection Station

Listed in table 1 (back of report) are USG

station numbers and names for the 29 water-qua

stations monitored during this study. The locati

the stations are illustrated in figure 1 in relation 

number preceding the USGS station number lis

table 1. 

Collection and Computation of Disch

Data

Data collection for discharge at stations 1

10, 13–17, 20–22, and 27–29 (table 1, fig. 1) co

of a continuous record of water stage and period

surements of streamflow over a wide range of w

stages. The discharge and water-stage data colle

these 18 stations were combined into a stage-di
3

relationship in order to compute continuous records of 

discharge for the 1999 water year.

Stations 18 and 19 (table 1, fig. 1) are situated 

within the backwater created by Coeur d’Alene Lake 

and, therefore, do not have a valid stage-discharge relationship. Their continuous records of discharge were 

computed with a USGS-developed numerical streamflow model named FourPt (DeLong and others, 1997), 

which uses channel geometry and water-stage data at 

upstream and downstream stations within the stream 

reach being modeled. The model was calibrated with 

individual discharge measurements over a wide range 

of discharge conditions.

Discharge measurements at miscellaneous 

streamflow measurement stations 6, 7, 9, 11, and 12 

were made over a wide range of water stages. Peak 

stages at these five stations were monitored with crest 

stage gages installed near each station’s measurement 

site. Synthetic hydrographs for the 1999 water year 

were generated for these five stations by correlating 

them to nearby continuous streamflow record stations. 

Four stations, 23 through 26 (table 1, fig. 1), 

began operation in May 1999 as a result of an amendment to Task 2. Discharge and water-stage data were 

insufficient for computation of a hydrograph for the 

1999 water year; therefore, only instantaneous discharges were available for these four stations.

Discharge measurements at the 29 stations were 

made using standardized USGS methods for collection 

of streamflow data, computation of discharge, and 

quality assurance procedures, which are thoroughly 

described in 6 USGS Techniques of Water-Resources 

Investigations reports (Buchanan and Somers, 1968, 

1969; Riggs, 1968; Carter and Davidian, 1968; 

Kennedy, 1983, 1984). 

Collection and Analysis of Water-Quality 

Data

The 24 stations that were operated throughout the 

1999 water year were subdivided into the following 

three priority groups for collection of water-quality 

samples: high priority, included new stations with 

expected high trace-element concentrations (stations 2, 

5, 6, 8, 9, and 11–13); moderate priority, included new 

stations with expected low trace-element concentrations (stations 1, 7, and 15) or existing stations with a 

limited number of historical trace-element analyses 

(stations 10, 18, and 19); and low priority, inclu

existing stations with numerous historical trace-e

analyses (stations 3, 4, 14, 16, 17, 20–22, 27, an

The objective at high- and moderate-priority sta

was to sample the full range of the hydrograph i

to develop a robust concentration versus flow re

ship. Low-priority stations already had a robust 

centration versus flow relationship; therefore, th

were sampled on a relatively fixed interval in or

facilitate more concentrated sampling efforts on 

and moderate-priority stations. Water-quality sa

were collected at each station between 9 and 15 

per year. The frequency of sampling was based 

station’s priority: high- and moderate-priority s

were sampled between 12 and 15 times, wherea

priority stations were sampled between 9 and 12 

Sampling of significant discharge events such a

on snow, spring snowmelt runoff, and thunderst

was emphasized at all stations. 

Five additional stations (23–26, and 28) w

added to the Spokane River in May 1999. Thes

tions were sampled on the same schedule applie

three full-year stations on the Spokane River (2

and 29).

Water-quality samples were collected each 

discharge measurement was made. Water tempe

pH, alkalinity, and specific conductance were m

onsite each time samples were collected; alkalin

measurements began in May 1999. Water sampl

collected with nonmetallic samplers and using c

sectional, depth-integrated sampling procedures 

described by Edwards and Glysson (1988). The 

vidual samples were composited in a churn spli

subsamples were withdrawn for laboratory anal

Samples destined for whole-water recoverable (

analyses were withdrawn initially; samples for 

solved analyses then were withdrawn via a peri

pump and nonmetallic filtration apparatus with 

pore size of 0.45 μm (Gelman capsule filters). E

capsule filter had been prerinsed with 1,000 mL 

deionized water. Trace-element samples were p

served with 2 mL of Ultrex nitric acid. Nutrient 

ples were preserved by acidification with 1 mL 

furic acid and chilling to 4°C. Water-quality sam

collection and field processing were conducted 

“clean” protocols that ensure noncontamination 

parts-per-billion level, as described by Horowit

others (1994). The samples were shipped in pla

coolers that were securely taped, custody sealed

logged-in on an enclosed chain-of-custody form
4

chain of custody was quite short—the field personnel 

shipped the samples via air to the USGS National 

Water-Quality Laboratory in Denver, Colorado. About 

10 percent of the sample load was submitted as blanks, 

spikes, and duplicates for quality assurance purposes as 

described by Friedman and Erdmann (1982).

For all stations, each water-quality sample was 

analyzed for WWR and dissolved concentrations of 

cadmium, lead, and zinc, as well as hardness. Nutrient 

concentrations (total phosphorus, dissolved orthophosphorus, total ammonia plus organic nitrogen, dissolved 

ammonia, and dissolved nitrite plus nitrate) were determined for water-quality samples collected at stations 4, 

14, 16 and 19–29. Water-quality samples were analyzed 

using low-level detection limit methods described by 

Fishman and Friedman (1989) and quality assurance/

quality control procedures described by Pritt and Raese 

(1995).

Calculation of Loads

The water-quality data were combined with discharge data to compute constituent loads for the 1999 

water year for all but five of the stations. Constituent 

loads for trace elements and nutrients were computed 

with the Loadest2 model (Crawford, 1996), which uses 

instantaneous concentration data and daily or unit discharge data to estimate annual and seasonal daily average constituent loads for a user-defined timeframe. Rating curve parameters and estimates of the mean load 

are computed by three methods: maximum likelihood, 

linear attribution, and least absolute deviation.

Annual loads could not be computed for stations 

23–26 and 28 because they lacked sufficient discharge 

and concentration data. Instantaneous loads, in pounds 

per day, were computed for these stations by multiplying the following four variables: instantaneous discharge, in cubic feet per second; constituent concentration in milligrams per liter; a conversion factor of 

0.0027 to convert discharge and concentration units; 

and a conversion factor of 2,000 to convert tons to 

pounds.

ANNUAL LOADS AND CONCENTRAT

1999 WATER YEAR

Hydrologic Loads

The mean daily discharge of the South Fo

Coeur d’Alene River (SFCDR) was 687 ft3/s, a

sured at SFCDR near Pinehurst (table 2, back o

report). Measured inflows from SFCDR above 

man Gulch, Canyon, Ninemile, Placer, Moon, G

ment Gulch, and Pine Creeks totaled 379 ft3/s. O

seven inflows, Pine Creek was the largest, 197 f

and Government Gulch was the smallest, 3.9 ft3

remaining inflow of 308 ft3/s was contributed b

ground water and unmeasured tributaries; the d

tion between the two sources can be evaluated w

data collected during the 1999 snowmelt-runoff 

tic (Woods, 2000). During the synoptic, 58.6 pe

the discharge measured at SFCDR near Pinehur

contributed by SFCDR above Deadman Gulch, 

yon, Ninemile, Placer, Moon, Government Gulc

Pine Creeks. Another 15.9 percent of Pinehurst

charge was contributed by six additional tributa

measured during the synoptic; of those six, Big 

contributed 90 percent. The remaining 25.5 per

Pinehurst’s inflow during the synoptic was attrib

ground-water inflow. On the basis of the synopt

ground-water inflow in the 1999 water year was 

to have contributed at least one-half of the unm

inflow of 308 ft3

/s within the SFCDR. Two reac

the SFCDR with substantial ground-water inflow

between Deadman Gulch and Silverton and bet

Silverton and Elizabeth Park. About 35 percent 

increase in discharge in each of these two reach

not accounted for by measured inflows. 

The mean daily discharge of the Coeur d’

River (CDR) near Cataldo (about 5 mi downstr

from the confluence of the North Fork Coeur d’

River (NFCDR) and SFCDR was 3,050 ft3/s (ta

The sum of discharges from the NFCDR at Ena

and SFCDR near Pinehurst was 2,930 ft3/s; this 

within 4 percent of the discharge measured nea

Cataldo and indicates that net ground-water infl

negligible. Mean daily discharge remained near

stant down the CDR, as measured at Rose Lake 

Harrison. The CDR near Cataldo has a long-ter

annual mean discharge of 2,530 ft3/s (Kjelstrom 

others, 1996); thus, discharge for the 1999 wate

was about 120 percent of long-term conditions.
5

Inflow to Coeur d’Alene Lake is from numerous 

sources but about 90 percent is from the CDR and the 

St. Joe River (Woods and Beckwith, 1997). The sum of 

mean daily discharges from CDR near Harrison, St. Joe 

River at Calder, and St. Maries River near Santa was 

6,040 ft3/s in the 1999 water year (table 2). The outflow 

from Coeur d’Alene Lake was 7,530 ft3/s, as measured 

at Spokane River near Post Falls. The difference of 

1,490 ft3/s between inflow and outflow is attributable to 

a combination of change in lake storage, unmeasured 

tributary inflows, the balance between precipitation and 

evaporation, and ground water. 

For the Spokane River, the mean daily discharge 

of 7,530 ft3/s near Post Falls was equal to that measured 

for the Spokane River at Spokane (table 2). The addition of 315 ft3/s from Hangman Creek and 690 ft3

/s 

from the Little Spokane River (R.R. Smith, U.S. Geological Survey, written commun., 2000) and other, 

unmeasured inflows increased the mean daily discharge 

of the Spokane River at Long Lake to 9,240 ft3/s, an 

18.5-percent increase from the Spokane gage. 

Cadmium Loads

DISSOLVED

The annual load of dissolved cadmium at SFCDR 

near Pinehurst was 6,790 lb, of which 3,790 lb was 

contributed by SFCDR above Deadman Gulch, Canyon, Ninemile, Placer, Moon, Government Gulch, and 

Pine Creeks (table 2). Of those seven sources, SFCDR 

above Deadman Gulch and Placer Creek added the 

least, 4 lb each, and Canyon Creek added the most, 

1,560 lb. Much of the 3,000 lb of dissolved cadmium 

not accounted for by measured sources was added via 

ground-water inflow to the SFCDR between Deadman 

Gulch and Pinehurst, with the majority added between 

Elizabeth Park and Pinehurst. A quantitative estimate 

of dissolved cadmium loads entering two reaches of the 

SFCDR via ground water was derived from three seepage studies conducted by the USGS in July, September, 

and October 1999 (G.J. Barton, U.S. Geological Survey, written commun., 2001). On the basis of an average daily load of 3 lb/d reported by Barton (written 

commun., 2001), the annual loads of dissolved cadmium from the Osburn Flats reach and Smelterville 

Flats reach totaled 1,100 lb and, thus, accounted for 

one-third of the 3,000 lb of dissolved cadmium not 

accounted for between Deadman Gulch and Pinehurst. 

The combined load of dissolved cadmium 

sured at NFCDR at Enaville and SFCDR near P

hurst was 6,940 lb, which was about equal to th

6,920 lb measured near Cataldo on the CDR (ta

The SFCDR contributed about 98 percent of the 

load near Cataldo. The annual load of dissolved 

mium down the CDR had increased to 7,570 lb 

Lake and to 7,910 lb near Harrison. The increas

tween Cataldo to Rose Lake and Rose Lake to H

were less than 10 percent and, therefore, were w

the range of discharge measurement error in thi

water-affected reach of the CDR. The percentag

tribution of dissolved cadmium load from the N

and SFCDR to the CDR near Harrison was 1.8 

86 percent, respectively.

Coeur d’Alene Lake received an annual di

cadmium load of 8,640 lb from the CDR, St. Joe

St. Maries Rivers (table 2). The lake discharged 3

of dissolved cadmium, as measured at Spokane 

near Post Falls. Thus, the lake retained about 4,

of its annual load of dissolved cadmium. From 

Falls, the dissolved cadmium load in the Spokan

increased slightly, to 3,940 lb, at Spokane and t

dropped by one-half, to 1,960 lb, at Long Lake. 

WHOLE-WATER RECOVERABLE

The annual load of WWR cadmium at SF

near Pinehurst was 7,920 lb, of which 4,140 lb 

contributed by SFCDR above Deadman Gulch, 

yon, Ninemile, Placer, Moon, Government Gulc

Pine Creeks (table 2). Of those seven sources, P

Creek added the least, 4 lb, and Canyon Creek 

the most, 1,790 lb. Of the 3,780 lb of WWR cad

not accounted for by measured sources, the maj

was added via ground-water inflow to the SFCD

between Elizabeth Park and Pinehurst; the rema

was from erosion and transport of sediment-bou

mium within the SFCDR between Silverton and 

hurst. 

The combined load of WWR cadmium m

at NFCDR at Enaville and SFCDR near Pinehu

8,100 lb, which was about 82 percent of the 9,8

measured near Cataldo on the CDR (table 2). T

SFCDR contributed about 80 percent of the ann

load near Cataldo; the NFCDR contributed abou

cent. The annual load of WWR cadmium down 

CDR had decreased to 8,790 lb at Rose Lake an

increased to 10,400 lb near Harrison. These dec

and increases were largely attributable to erosio
6

transport, and deposition of sediment-bound cadmium 

because the load of dissolved cadmium down the CDR 

did not vary more than discharge measurement error. 

The percentage contribution of WWR cadmium load 

from the NFCDR and SFCDR to the CDR near Harrison was 1.8 and 76 percent, respectively.

Coeur d’Alene Lake received an annual WWR 

cadmium load of 11,100 lb from the CDR, St. Joe, and 

St. Maries Rivers; the CDR added 93.5 percent of that 

load (table 2). The lake discharged 4,940 lb of WWR 

cadmium and, thus, retained about 6,260 lb of its 

annual load. From Post Falls, the WWR cadmium load 

in the Spokane River decreased slightly, to 4,310 lb, at 

Spokane and then decreased further, to 2,110 lb, at 

Long Lake. The high trapping efficiencies of both 

Coeur d’Alene and Long Lakes are well illustrated by 

the substantial decreases in annual loads of dissolved 

and WWR cadmium measured downstream from each 

lake.

Cadmium Concentrations

Mean flow-weighted concentrations of dissolved 

cadmium during the 1999 water year ranged from a 

low of 0.033 μg/L at Canyon Creek near Burke and 

NFCDR at Enaville to a high of 185 μg/L at Government Gulch (table 3, back of report). Of the 29 stations 

in the network, 9 had dissolved cadmium concentrations less than 0.1 μg/L, 5 of which were within the 

SFCDR Basin (SFCDR above Deadman Gulch, Canyon Creek near Burke, Placer Creek, Moon Creek, and 

Pine Creek). The five stations with the highest concentrations were all within the SFCDR Basin and included 

Government Gulch, 185 μg/L; East Fork Ninemile 

Creek, 33.3 μg/L; Ninemile Creek, 17.7 μg/L; Canyon 

Creek above mouth, 13.3 μg/L; and Canyon Creek at 

Woodland Park, 8.2 μg/L.

 Mean flow-weighted concentrations of WWR 

cadmium during the 1999 water year ranged from a 

low of 0.04 μg/L at NFCDR at Enaville to a high of 

186 μg/L at Government Gulch (table 3). As with dissolved cadmium, the same nine stations had WWR concentrations less than 0.1 μg/L and the same five stations 

had WWR concentrations higher than 10 μg/L. At most 

stations, WWR concentrations of cadmium were less 

than 20 percent higher than dissolved concentrations.

Lead Loads

DISSOLVED

At the SFCDR near Pinehurst, the annual 

dissolved lead was 5,920 lb, of which 4,220 lb 

contributed by SFCDR above Deadman Gulch, 

yon, Ninemile, Placer, Moon, Government Gulc

Pine Creeks (table 2). Of those seven sources, M

Creek added the least, 7 lb, and Canyon Creek 

the most, 3,000 lb. The additional 1,700 lb of di

lead not accounted for by measured surface-wa

sources was the net result of the interaction of g

water and surface water within the SFCDR betw

Deadman Gulch and Pinehurst. For stream reach

gained ground water, the dissolved lead carried 

ground water would geochemically interact wit

iron in surface water to form colloidal iron-lead 

plexes via adsorption. Where this process was o

cient magnitude and stream discharge was low, 

tion of the iron-lead complexes would be depos

within the stream channel. Periodic increases in 

discharge would resuspend and transport the iro

complexes downstream. Water-quality samples 

downstream from ground-water recharge reache

would be enriched in dissolved lead because di

concentrations are operationally defined as the 

passing a 0.45-μm filter pore size; thus, the coll

iron-lead complexes (smaller than 0.45 μm) wo

included in such filtrates. On an annual basis, di

lead load in the SFCDR decreased between Dea

Gulch and Elizabeth Park, likely because of geo

cal adsorption of lead to iron; however, dissolve

load increased from Elizabeth Park to Pinehurst

due to resuspension and transport of iron-lead c

plexes and addition of lead-bearing ground wat

three seepage studies previously discussed in re

to dissolved cadmium loads also measured grou

water loads of dissolved lead during low-discha

conditions (G.J. Barton, U.S. Geological Survey

ten commun., 2001). The seepage studies revea

average daily loss of about 1.4 and 0.8 lb of dis

lead within the Osburn Flats and Smelterville F

reaches of the SFCDR, respectively. 

The combined load of dissolved lead meas

NFCDR at Enaville and SFCDR near Pinehurst 

6,570 lb, which was 4,230 lb less than that mea

near Cataldo on the CDR (table 2). The SFCDR 

tributed about 55 percent of the annual load nea

aldo; the NFCDR contributed 6 percent. On the 
7

these three stations, there is a substantial source of dissolved lead load between Pinehurst and Enaville and 

Cataldo. This additional load could result from some 

combination of the following three sources: (1) ground 

water from the SFCDR Basin may add dissolved lead 

to the CDR if the reach between Pinehurst and Cataldo 

gains ground water; (2) lead may be desorbed from 

sediments within the water column as the NFCDR (low 

WWR lead concentration, 0.15 μg/L) mixes with the 

SFCDR (high WWR lead concentration, 4.4 μg/L); 

(3) dissolved concentrations are operationally defined 

as the filtrate passing a 0.45-μm filter pore size; thus, 

colloidal iron-lead complexes formed in the SFCDR 

would be included in such filtrates and would inflate 

the dissolved concentrations. 

The annual load of dissolved lead between Cataldo and Rose Lake increased to 15,800 lb; between 

Rose Lake and Harrison, it increased another 24,100 lb, 

to 39,900 lb. The percentage contribution of dissolved 

lead load from the NFCDR and SFCDR to the CDR 

near Harrison was 1.6 and 15 percent, respectively. The 

overall increase of 29,100 lb between Cataldo and Harrison indicates the CDR as a substantial source of dissolved lead to Coeur d’Alene Lake. The likely sources 

of dissolved lead are analogous to those discussed in 

the preceding paragraph, except that the source of 

ground water would be the flood plain adjacent to the 

CDR. 

Coeur d’Alene Lake received an annual dissolved 

lead load of 40,300 lb from the CDR, St. Joe, and St. 

Maries Rivers; all but 392 lb came from the CDR (table 

2). The lake discharged 6,190 lb of dissolved lead; 

thus, the lake retained the vast majority of its annual 

load of dissolved lead. From Post Falls, the dissolved 

lead load in the Spokane River increased to 8,860 lb at 

Spokane, then dropped slightly, to 7,150 lb, at Long 

Lake. 

WHOLE-WATER RECOVERABLE

The annual load of WWR lead at SFCDR near 

Pinehurst was 166,000 lb, of which 34,500 lb was contributed by SFCDR above Deadman Gulch, Canyon, 

Ninemile, Placer, Moon, Government Gulch, and Pine 

Creeks (table 2). Of those seven sources, Moon Creek 

added the least, 59 lb, and Canyon Creek added the 

most, 27,700 lb. Of the 132,000 lb of WWR lead not 

accounted for by measured sources, the largest amount, 

98,800 lb, was added to the SFCDR between Elizabeth 

Park and Pinehurst; another 25,000 lb was added 

between Silverton and Elizabeth Park. Interpret

these changes in WWR lead load is complicated 

likely geochemical interaction of dissolved lead 

iron. Dissolved lead can be geochemically conv

WWR lead via adsorption to iron. During perio

low stream discharge, much of this authegenic W

lead would be retained in the stream channel as 

conversion of dissolved to WWR lead progresse

When stream discharge increases during runoff 

the authegenic lead would be transported down

to be measured as part of the WWR lead load. T

authegenically derived WWR lead load is in add

the erosion and transport of sediment-bound lea

measured as WWR lead load.

The combined load of WWR lead measur

at NFCDR at Enaville and SFCDR near Pinehu

was 173,000 lb, which was about 87 percent of 

200,000 lb measured near Cataldo on the CDR 

2). The SFCDR contributed 83 percent of the an

load near Cataldo; the NFCDR contributed abou

cent. The annual load of WWR lead down the C

increased to 246,000 lb by Rose Lake. By far th

est increase occurred between Rose Lake and H

son—an addition of 344,000 lb yielded 590,000 

WWR lead load near Harrison. The percentage c

bution of WWR lead load from the NFCDR and S

to the CDR near Harrison was 1.2 and 28 perce

respectively. The increased load of dissolved le

accounts for only a small portion of the increas

WWR lead between Cataldo and Harrison. An i

tant hydrologic process that can account for som

the increase is the erosion and transport of sedim

bound lead contained in the river’s channel and 

A second process is the authegenic conversion o

solved lead to WWR lead. The relative magnitu

the two processes has yet to be quantified; howe

incidence of riverbank erosion and the fine-grai

nature of channel and bank sediments points to 

and transport as the dominant process. 

Coeur d’Alene Lake received an annual W

lead load of 591,000 lb from the CDR, St. Joe, 

Maries Rivers; the CDR contributed all but 725 

(table 2). The lake discharged 51,300 lb of WW

and, thus, retained more than 90 percent of its a

load. Between the Post Falls and Spokane statio

WWR lead load in the Spokane River decreased 

6,000 lb. Between the Spokane and the Long L

tions, the load decreased another 20,300 lb. The 

trapping efficiencies of both Coeur d’Alene and 

Lakes are well illustrated by the substantial dec
8

in the annual load of WWR lead measured downstream 

from each lake.

Lead Concentrations

In contrast to cadmium, the percentage of dissolved lead to WWR lead was low because lead tends 

to be associated with sediment particles. Mean flowweighted concentrations of dissolved lead ranged from 

a low of 0.048 μg/L at NFCDR near Prichard and St. 

Joe River at Calder to a high of 63.1 μg/L at East Fork 

Ninemile Creek (table 3). WWR concentrations ranged 

from a low of 0.076 μg/L at St. Joe at Calder to a high 

of 236 μg/L at Canyon Creek above mouth. 

Zinc Loads

DISSOLVED

At the SFCDR near Pinehurst, the annual load of 

dissolved zinc was 945,000 lb, of which 425,000 lb 

was contributed by SFCDR above Deadman Gulch, 

Canyon, Ninemile, Placer, Moon, Government Gulch, 

and Pine Creeks (table 2). Of those seven sources, 

Placer Creek added the least, 126 lb, and Canyon Creek 

added the most, 216,000 lb. About 520,000 lb of dissolved zinc was not accounted for by measured 

sources; the majority was likely added via groundwater inflow to the SFCDR between Elizabeth Park and 

Pinehurst. A quantitative estimate of dissolved zinc 

loads entering two reaches of the SFCDR via ground 

water was derived from three seepage studies conducted by the USGS in July, September, and October 

1999 (G.J. Barton, U.S. Geological Survey, written 

commun., 2001). On the basis of an average daily load 

of 942 lb/d reported by Barton (written commun., 

2001), the annual loads of dissolved zinc from the 

Osburn Flats reach and Smelterville Flats reach totaled 

344,000 lb and, thus, accounted for about two-thirds of 

the 520,000 lb of dissolved zinc not accounted for 

between Deadman Gulch and Pinehurst. 

The combined load of dissolved zinc measured at 

NFCDR at Enaville and SFCDR near Pinehurst was 

969,000 lb, which was about 7 percent less than that 

measured near Cataldo on the CDR (table 2). The 

SFCDR contributed about 91 percent of the annual 

load near Cataldo; the NFCDR contributed 2.3 percent. 

The annual load of dissolved zinc for the CDR b

Cataldo and Rose Lake increased to 1,200,000 

between Rose Lake and Harrison, it increased t

1,270,000 lb. The percentage contribution of di

zinc load from the NFCDR and SFCDR to the C

near Harrison was 1.9 and 74 percent, respectiv

Coeur d’Alene Lake received an annual di

zinc load of 1,280,000 lb from the CDR, St. Joe

St. Maries Rivers; all but 8,400 lb came from th

(table 2). The lake discharged 1,060,000 lb, nea

of its influent load of dissolved zinc. Downstrea

Post Falls, the dissolved zinc load in the Spokan

decreased to 875,000 lb at Spokane, then dropp

577,000 lb at Long Lake.

WHOLE-WATER RECOVERABLE

The annual load of WWR zinc at SFCDR 

Pinehurst was 1,190,000 lb, of which 456,000 l

contributed by SFCDR above Deadman Gulch, 

yon, Ninemile, Placer, Moon, Government Gulc

Pine Creeks (table 2). Of those seven sources, P

Creek added the least, 287 lb, and Canyon Creek 

the most, 241,000 lb. Of the 734,000 lb of WW

not accounted for by measured sources, about t

thirds was added to the SFCDR between Silver

Pinehurst. Inflow of zinc-laden ground water an

sion and transport of sediment-bound zinc were 

likely sources within the SFCDR.

The combined load of WWR zinc measur

NFCDR at Enaville and SFCDR near Pinehurst 

1,240,000 lb, which was about 96 percent of the 

1,300,000 lb measured near Cataldo on the CDR 

2). The SFCDR contributed about 92 percent of 

annual load near Cataldo; the NFCDR contribu

about 4 percent. The annual load of WWR zinc 

the CDR had increased to 1,500,000 lb at Rose 

and then increased to 1,570,000 lb near Harriso

percentage contribution of WWR zinc load from 

NFCDR and SFCDR to the CDR near Harrison 

and 76 percent, respectively.

Coeur d’Alene Lake received an annual W

zinc load of 1,580,000 lb from the CDR, St. Joe

St. Maries Rivers; the CDR added over 99 perc

the load (table 2). The lake discharged 1,080,00

WWR zinc and, thus, retained about 500,000 lb 

annual load. From Post Falls, the WWR zinc loa

Spokane River decreased to 989,000 lb at Spok

then decreased further, to 764,000 lb at Long L
9

Zinc Concentrations

Mean flow-weighted concentrations of dissolved 

zinc during the 1999 water year ranged from a low 

of 0.92 μg/L at NFCDR near Prichard to a high of 

6,220 μg/L at Government Gulch (table 3). For WWR 

zinc, the St. Joe River at Calder had the lowest concentration, 1.3 μg/L, and Government Gulch had the highest, 6,320 μg/L. Five of the 29 stations had dissolved 

and WWR concentrations of zinc in excess of 

1,000 μg/L. 

Nutrient Loads

NITROGEN

Annual loads of total nitrogen (sum of total 

ammonia plus organic nitrogen and dissolved nitrite 

plus nitrate) from the NFCDR (measured at Enaville) 

and SFCDR (measured near Pinehurst) were 527,000 lb 

and 360,000 lb, respectively (table 4, back of report). 

The combined load of the SFCDR and NFCDR, 

887,000 lb, was larger than the 767,000 lb measured in 

the CDR near Harrison; thus, total nitrogen was lost in 

that river reach, probably via deposition of sedimentbound organic nitrogen. 

Coeur d’Alene Lake received 1,320,000 lb of 

total nitrogen from the CDR, St. Joe, and St. Maries 

Rivers; about 58 percent was supplied by the CDR 

(table 4). The lake discharged 2,430,000 lb via the Spokane River, as measured near Post Falls. Part of the 

1,110,000 lb difference between inflow and outflow 

was attributable to unmeasured sources of total nitrogen and trapping by the lake. An estimate of the 

unmeasured sources of total nitrogen was made using 

the 1992 nutrient budget for Coeur d’Alene Lake 

reported by Woods and Beckwith (1997). During their 

limnological study, Woods and Beckwith measured 

nutrient loads near the mouth of the St. Joe River as 

well as at St. Joe River at Calder and St. Maries River 

near Santa. The combined load of total nitrogen from 

the latter two stations was 78 percent of that measured 

near the mouth of the St. Joe River. Therefore, the 

557,000 lb contributed in 1999 by the St. Joe River at 

Calder and St. Maries River near Santa would have 

increased to about 714,000 lb at the mouth, an additional load of 157,000 lb. In 1992, about 28 percent of 

the lake’s inflow of total nitrogen was from sources 

other than the CDR and St. Joe Rivers; therefore, in 

1999, the lake received about 410,000 lb of tota

gen from these other sources. On the basis of th

nutrient budget in Woods and Beckwith (1997), 

1,320,000 lb of total nitrogen input in 1999 cou

increased by 157,000 lb and 410,000 lb to yield 

input of 1,890,000 lb. The inflow load was less t

outflow load by 540,000 lb; thus, Coeur d’Alen

had a net export of total nitrogen in 1999.

Between the Post Falls and Spokane statio

Spokane River gained 1,600,000 lb of total nitr

By far the largest increase was between the stat

Spokane and Long Lake; the river gained 8,970

to yield 13,000,000 lb of total nitrogen at the do

stream-most station in the Spokane River Basin

man Creek contributed 807,000 lb of that load, 

basis of a mean daily discharge of 315 ft3/s and 

median concentration of 1,300 μg/L of total nit

during the 1999 water year (R.R. Smith, U.S. G

cal Survey, written commun., 2000). The City o

kane’s wastewater treatment plant also discharg

effluent into this reach of the Spokane River; ho

no data were available to calculate the total nitr

load of the effluent. 

PHOSPHORUS

Annual loads of total phosphorus from th

NFCDR and SFCDR were 58,200 lb and 47,30

respectively (table 4). The small increase of 1,5

total phosphorus load between the confluence o

NFCDR and SFCDR and the mouth of the CDR 

Harrison was within the margin of discharge m

ment error. 

Coeur d’Alene Lake received 153,000 lb 

phosphorus from the CDR, St. Joe, and St. Mar

ers; about 70 percent was supplied by the CDR 

4). The lake discharged 187,000 lb via the Spok

River. The difference between inflow and outflo

attributable to unmeasured sources of total phos

As was done for total nitrogen, the 1992 nutrien

get reported by Woods and Beckwith (1997) wa

to estimate the unmeasured inputs of total phos

The ratio for total phosphorus loads between the 

of the St. Joe River and the combined loads from 

St. Joe River at Calder and St. Maries River nea

was 0.73. In 1999, the latter two stations carrie

45,500 lb of total phosphorus, which would hav

increased to 62,300 lb near the mouth of the St. 

River. About 49 percent of the 1992 load of tota

phorus to Coeur d’Alene Lake was from source
10

than the CDR and St. Joe River; therefore, in 1999, the 

lake received about 83,000 lb of total phosphorus from 

these other sources. On the basis of the 1992 nutrient 

budget in Woods and Beckwith (1997), the 153,000 lb 

of total phosphorus input in 1999 could be increased by 

16,800 lb and 83,000 lb to yield an input of 253,000 lb. 

On the basis of the difference between inflow and outflow, Coeur d’Alene Lake trapped about 66,000 lb of 

total phosphorus in 1999. 

Between the stations at Post Falls and Spokane, 

the Spokane River lost 13,000 lb of total phosphorus. 

Between the stations at Spokane and Long Lake, the 

river gained 503,000 lb; thus, the downstream-most 

station in the Spokane River Basin delivered 677,000 lb 

of total phosphorus to the Columbia River. Hangman 

Creek contributed 27,300 lb of that load, on the basis of 

a mean daily discharge of 315 ft3/s and a median concentration of 44 μg/L of total phosphorus during the 

1999 water year (R.R. Smith, U.S. Geological Survey, 

written commun., 2000). The City of Spokane’s wastewater treatment plant discharged 138,000 lb of total 

phosphorus into this reach of the Spokane River (S. 

Fredrickson, City of Coeur d’Alene, written commun., 

2000). 

COMPARISON OF NUTRIENT LOADS IN CALENDAR 

YEAR 1991 AND WATER YEAR 1999

Nutrient load data collected during this study 

(table 4) were compared to those collected during the 

1991–92 limnological study of Coeur d’Alene Lake 

reported by Woods and Beckwith (1997). Daily mean 

discharges in calendar year 1991 and water year 1999 

were comparable; the former was 130 percent of normal and the latter was 120 percent of normal. The comparison revealed a substantial change in the relative 

magnitude of total phosphorus loads to Coeur d’Alene 

Lake from the CDR and St. Joe River. In 1991, the 

CDR contributed 48,500 lb (22,000 kilograms, or kg) 

of total phosphorus, whereas the St. Joe River near its 

mouth contributed 159,000 lb (72,100 kg). However, 

the CDR was the dominant contributor, at 107,000 lb, 

during the 1999 water year; only 62,300 lb (45,500 lb 

divided by 0.73) was contributed by the St. Joe River 

near its mouth. The relative magnitude of total nitrogen 

loads also shifted, but to a lesser degree. The CDR contributed 1,770,000 lb (801,000 kg) of total nitrogen in 

1991; the St. Joe River near its mouth contributed 

2,290,000 lb (1,040,000 kg). During the 1999 water 

year, the 767,000 lb of total nitrogen from the CDR 

exceeded the 714,000 lb (557,000 lb divided by 

contributed by the St. Joe River near its mouth. 

The substantial decline in total nitrogen lo

both stations between calendar year 1991 and w

year 1999 is actually an artifact of changes in an

detection and reporting limits at the USGS Nati

Water-Quality Laboratory. In the early 1990’s, t

oratory’s reporting limit for total ammonia plus 

nitrogen was 200 μg/L; concentrations less than 

were reported as “less than.” Total nitrogen con

tions used by Woods and Beckwith (1997) to co

1991 loads used 200 μg/L for reported “less tha

ues. In the late 1990’s, the laboratory’s reportin

was reduced to 100 μg/L; this accounts for muc

difference between 1991 and the 1999 water ye

Compared to 1991, total phosphorus load

ered to Coeur d’Alene Lake by the CDR appear 

increased substantially in proportion to those co

uted by the St. Joe River; a similar, but smaller, 

was also noted for total nitrogen loads. One cou

ulate that this shift in the proportion of loads m

due to a combination of the following four reas

(1) population in the CDR Basin has increased 

tion to that in the St. Joe River Basin, (2) waste

treatment plants in the CDR Basin have increas

annual loads in relation to those in the St. Joe R

Basin, (3) stream channel and watershed remed

activities in the SFCDR Basin have increased st

loads of phosphorus-bearing sediments, and (4) 

shed rehabilitation activities in the St. Joe River 

have successfully reduced nutrient loads. Howe

anecdotal information gathered from numerous 

viduals involved in water-quality management o

two basins did not support any of the four reaso

stated above.

An in-depth evaluation of discharge and w

quality data indicated that the shift in the propo

nutrient loads between the CDR and St. Joe Riv

largely attributable to the location and timing of 

collection. In 1991, the location of discharge m

ments and sampling was on the St. Joe River ne

mouth at St. Maries; in the 1999 water year, dis

and sampling were conducted upstream, at St. J

River at Calder and St. Maries River near Santa

cause the station near the mouth was discontinu

1993. This shift in sampling locations meant th

low-gradient, depositional reach of the lower St

River was not sampled during the 1999 water y

thus, nutrients that may have been eroded and t

ported were not sampled. Factors were applied 
11

1999 water year loads measured at St. Joe River at 

Calder and St. Maries River near Santa in order to estimate the probable loads delivered to Coeur d’Alene 

Lake. The two factors, 0.73 for total phosphorus and 

0.78 for total nitrogen, likely underestimated the 1999 

water year loads because the two factors were developed from data collected in 1992, a year in which discharge was only about 60 percent of normal (Woods 

and Beckwith, 1997). The factors were developed by 

concurrently measuring loads of total phosphorus and 

total nitrogen at the three stations in the St. Joe River 

Basin—St. Joe River at Calder, St. Maries River near 

Santa, and St. Joe River at St. Maries (discontinued in 

1993). The low discharges of 1992 would have been 

less likely to have eroded and transported nutrients in 

the low-gradient reach upstream from St. Maries; thus, 

the two factors likely underestimated loads delivered to 

Coeur d’Alene Lake. In contrast, discharge measurements and sampling of the CDR during 1991 and the 

1999 water year have been conducted near the river’s 

mouth and downstream from its low-gradient, depositional reach. In regard to the timing of sample collection, both rivers were sampled near their mouths and 

near their peak discharges of 1991. Total phosphorus 

concentrations near the peak discharges were 77 μg/L 

for the St. Joe River and 24 μg/L for the CDR (Harenberg and others, 1992). In contrast, the peak discharges 

of the 1999 water year were not sampled equivalently 

between the two basins. On the CDR, a total phosphorus concentration of 53 μg/L was measured near the 

discharge peak of the 1999 water year; samples at St. 

Joe River at Calder and St. Maries River near Santa 

were collected prior to and after the discharge peak and 

were less than 15 μg/L (Brennan and others, 2000). 

The net effect of differences in sampling locations and 

timing during the 1999 water year was to underestimate the nutrient loads delivered by the St. Joe River, 

thereby giving the false impression that nutrient loads 

delivered by the CDR had proportionally increased 

over those of the St. Joe River.

Nutrient Concentrations

Mean flow-weighted concentrations of total nitrogen ranged from 91 μg/L at St. Joe River at Calder to 

713 μg/L at Spokane River at Long Lake (table 5, back 

of report). Two stations, SFCDR near Pinehurst and 

Spokane River at Spokane, had the second-highest concentrations of total nitrogen, 266 and 272 μg/L, 

tively. The upstream-most station on the Spokan

River, near Post Falls, had a total nitrogen conc

tion of 164 μg/L. The remaining stations had to

nitrogen concentrations less than 130 μg/L. 

In addition to total nitrogen, dissolved nitr

nitrate, dissolved ammonia, and total ammonia 

organic nitrogen were measured (table 5). Spok

River at Long Lake had the largest concentratio

dissolved nitrite plus nitrate, 604 μg/L, and the 

ratio of nitrite plus nitrate to total nitrogen, 0.85

contrast, dissolved nitrite plus nitrate was less t

25 μg/L at four stations, NFCDR near Prichard 

Enaville, St. Joe River at Calder, and St. Maries 

near Santa. Dissolved ammonia concentration w

highest, 51 μg/L, at SFCDR near Pinehurst and 

3 μg/L, at the two NFCDR stations and St. Joe R

Calder. Of the nine stations sampled for nutrien

had total ammonia plus organic nitrogen concen

tions near 100 μg/L; two ranged from 124 to 15

and the Spokane River at Long Lake had the hig

212 μg/L.

Mean flow-weighted concentrations of tot

phorus ranged from 7 μg/L at St. Joe River at C

and NFCDR above Shoshone Creek to 37 μg/L 

kane River at Long Lake (table 5). SFCDR near 

hurst had the second-highest concentration, 35 

The remaining stations had total phosphorus co

tions between 7 and 18 μg/L. Mean flow-weigh

centrations of dissolved orthophosphorus range

2 μg/L at Spokane River near Post Falls to 26 μ

Spokane River at Long Lake (table 5). The highe

of dissolved orthophosphorus to total phosphor

0.7 at Spokane River at Long Lake.

REFERENCES CITED

Brennan, T.S., Campbell, A.M., Lehmann, A.K

O’Dell, Ivalou, 2000, Upper Columbia Ri

Basin and Snake River Basin below King 

Water resources data, Idaho, water year 19

U.S. Geological Survey Water-Data Repo

ID–99–2, 440 p.

Buchanan, T.J., and Somers, W.P., 1968, Stage 

surements at gaging stations: U.S. Geolog

Survey Techniques of Water Resources In

tions, book 3, chap. A7, 28 p.
12

——— 1969, Discharge measurements at gaging stations: U.S. Geological Survey Techniques of 

Water-Resources Investigations, book 3, 

chap. A8, 65 p.

Carter, R.W., and Davidian, J., 1968, General procedure for gaging streams: U.S. Geological Survey 

Techniques of Water-Resources Investigations, 

book 3, chap. A6, 13 p.

Crawford, C.G., 1996, Estimating mean constituent 

loads in rivers by the rating-curve and flowduration, rating-curve methods: Bloomington, 

Ind., Indiana University, Ph.D. dissertation, 

245 p.

DeLong, L.L., Thompson, D.B., and Lee, J.K., 1997, 

The computer program FourPt (version 95.01)— 

a model simulating one-dimensional, unsteady, 

open-channel flow: U.S. Geological Survey 

Water-Resources Investigations Report 97–4016, 

69 p.

Edwards, T.K., and Glysson, G.D., 1988, Field methods for measurement of fluvial sediment: U.S. 

Geological Survey Open-File Report 86–531, 

118 p.

Fishman, M.J., and Friedman, L.C., eds., 1989, Methods for determination of inorganic substances in 

water and fluvial sediments: U.S. Geological Survey Techniques of Water-Resources Investigations, book 5, chap. A1, 545 p.

Friedman, L.C., and Erdmann, D.E., 1982, Quality 

assurance practices for the chemical and biological analyses of water and fluvial sediments: U.S. 

Geological Survey Techniques of WaterResources Investigations, book 5, chap. A6, 

181 p.

Harenberg, W.A., Jones, M.L., O’Dell, Ivalou, Brennan, T.S., Lehmann, A.K., and Tungate, A.M., 

1992, Upper Columbia River Basin and Snake 

River Basin below King Hill, Water resources 

data, Idaho, water year 1991: U.S. Geological 

Survey Water-Data Report ID–91–2, 357 p.

Horowitz, A.J., Demas, C.R., Fitzgerald, K.K., 

T.L., and Rickert, D.A., 1994, U.S. Geolo

Survey protocol for the collection and pro

of surface-water samples for the subseque

determination of inorganic constituents in 

water: U.S. Geological Survey Open-File 

94–539, 57 p.

Kennedy, E.J., 1983, Computation of continuou

records of streamflow: U.S. Geological Su

Techniques of Water-Resources Investigat

book 3, chap. A13, 53 p.

——— 1984, Discharge ratings at gaging statio

U.S. Geological Survey Techniques of Wa

Resources Investigations, book 3, chap. A

59 p.

Kjelstrom, L.C., Stone, M.A.J., and Harenberg, 

1996, Statistical summaries of streamflow 

for selected gaging stations in Idaho and a

States through September 1990—Volume 

ing stations with 10 or more years of recor

Geological Survey Water-Resources Inves

tions Report 94–4069, 533 p.

Pritt, J.W., and Raese, J.W., eds., 1995, Quality 

ance/quality control manual, National Wa

Quality Laboratory: U.S. Geological Surv

Open-File Report 95–443, 35 p.

Riggs, H.C., 1968, Some statistical tools in hyd

U.S. Geological Survey Techniques of Wa

Resources Investigations, book 4, chap. A

Woods, P.F., 2001, Concentrations and loads of 

mium, lead, and zinc measured near the p

of the 1999 snowmelt-runoff hydrographs 

42 water-quality stations, Coeur d’Alene R

Basin, Idaho: U.S. Geological Survey Op

Report 00–322, 61 p. Also available at UR

http://idaho.usgs.gov/PDF/ofr00322/index

Woods, P.F., and Beckwith, M.A., 1997, Nutrie

trace-element enrichment of Coeur d’Alen

Idaho: U.S. Geological Survey Water-Sup

Paper 2485, 93 p.
FIGURE 1

U%

$T $T $T

$T

$T

$T

$T

$T

$T$T

$T

$T

$T

$T $T$T

$T

$T $T $T

$T

$T

$T

$T $T

$T$T

$T

Spokane

Coeur d'Alene

Hangman Creek

Spokane River

Coeur d'Alene River

St. Joe River

St. Maries River

Little Spokane

River

Spokane River

South Fork

Monta

Idaho

Washington

Idaho Coeur d'Alene Indian Reservation

North Fork

Lake Roosevelt

Lake Spokane

Lake Coeur d'Alene

1

7

6

5

9

2

3 4

24

26 25 14

15 16

10

11 12 13 17 18 19

20

21

2322 28

29 Stevens

Lincoln

Adams

Shoshone

Bonner

Whitman

Spokane

Latah

Kootenai

Benewah

8

27

0

0

10 

10 20 3

47

117

116

o

o 48 118

o

o

o

$ Gaging station and number Explanation

Bunker Hill Superfund Site

 

 

Base from U.S. Geological Survey digital data, 1:100,000, 1999 Albers Equal-Area projection standard parallels 43 30', 47 30', and -114 00', 41 45' no false easting or false northing.

15

o o

o o

Figure 1. Locations of 29 water-quality stations monitored during the 1999 water year wit

Spokane River Basin, Idaho and Washington.
Blank page 8
TABLES 1–5

Continuous Miscellaneous Model-Derived

12411000

NFCDR above

Shoshone Creek

near Prichard

X

12411935

Prichard Creek

at mouth

at Prichard

X

12413000 NFCDR at Enaville X12413040

SFCDR above

Deadman Gulch

near Mullan

X

12413118 Canyon Creek near Burke X12413123 Canyon Creek at Woodland Park X12413125

Canyon Creek

above mouth

at Wallace

X

12413127

East Fork Ninemile 

Creek above mouth 

near Blackcloud

X

logical Survey station numbers and names for 29 water-quality stations monitored during the 1999 water year 

 River Basin, Idaho and Washington

USGS

Station Number

USGS

Station Name

Type of Discharge-Record Collection

Fork Coeur d'Alene River; SFCDR, South Fork Coeur d'Alene River; CDR, Coeur d'Alene River; SR, Spokane River; 

ogical Survey]
Continuous Miscellaneous Model-Derived

USGS

Station Number

USGS

Station Name

Type of Discharge-Record Collection

12413130

Ninemile Creek

above mouth

at Wallace

X

12413140 Placer Creek at Wallace X12413150 SFCDR at Silverton X12413190

Moon Creek

above mouth

at Elk Creek

X

12413210

SFCDR at 

Elizabeth Park

near Kellogg

X

12413290

Government Gulch

near mouth

at Smelterville

X

12413445

Pine Creek

below Amy Gulch

near Pinehurst

X

12413470 SFCDR near Pinehurst X

12413500 CDR near Cataldo X
Continuous Miscellaneous Model-Derived

USGS

Station Number

USGS

Station Name

Type of Discharge-Record Collection

12413810 CDR at Rose Lake X12413860 CDR near Harrison X

12414500 St. Joe River at Calder X

12414900 St. Maries River near Santa X12419000 SR near Post Falls X

12419500

SR above Liberty

Bridge near Otis

Orchard

X

12420500 SR at Greenacres X12420800

SR at Sullivan

Road Bridge near

Trentwood

X

12422000 SR below Green St. at Spokane X
Continuous Miscellaneous Model-Derived

USGS

Station Number

USGS

Station Name

Type of Discharge-Record Collection

12422500 SR at Spokane

X

12424000 Hangman Creek at Spokane

X

12433000 SR at Long Lake

X
Dissolved WWR Dissolved WWR Dissolved WWR

411000

NFCDR above

Shoshone Creek

near Prichard

78 78 79 341 1,520 3,900 836

411935

Prichard Creek

at mouth

at Prichard

52 72 140 2,000 12,700 15,500 225

413000 NFCDR at Enaville 145 183 646 7,290 24,200 51,400 2,240413040

SFCDR above

Deadman Gulch

near Mullan

4 6 28 421 699 1,440 46

413118 Canyon Creek near Burke 3 6 44 128 657 755 40413123 Canyon Creek at Woodland Park 893 951 2,520 16,900 128,000 129,000 55.1

ly discharge and annual loads of dissolved and whole-water recoverable cadmium, lead, and 

sured during the 1999 water year at 24 water-quality stations within the Spokane River Basin, 

d Washington

Fork Coeur d'Alene River; SFCDR, South Fork Coeur d'Alene River; CDR, Coeur d'Alene River;

er; WWR, whole-water recoverable; ft3/s, cubic feet per second; USGS, U.S. Geological Survey]

USGS

on Number

USGS

Station Name

Cadmium 

Annual Load 

(pounds)

Lead

Annual Load

(pounds)

Zinc

Annual Load

(pounds) Mean Daily Discharge

(ft3/s)
Dissolved WWR Dissolved WWR Dissolved WWR

USGS

on Number

USGS

Station Name

Cadmium 

Annual Load 

(pounds)

Lead

Annual Load

(pounds)

Zinc

Annual Load

(pounds) Mean Daily Discharge

(ft3/s)

413125

Canyon Creek

above mouth

at Wallace

1,560 1,790 3,000 27,700 216,000 241,000 59.6

413127

East Fork Ninemile 

Creek above mouth 

near Blackcloud

590 593 1,120 3,240 98,800 99,600 9

413130

Ninemile Creek

above mouth

at Wallace

648 760 951 4,700 112,000 120,000 18.6

413140 Placer Creek at Wallace 4 4 23 91 126 287 45.2413150 SFCDR at Silverton 2,760 2,700 3,790 42,200 408,000 405,000 268413190

Moon Creek

above mouth

at Elk Creek

7 7 7 59 1,320 1,360 9.1

413210

SFCDR at 

Elizabeth Park

near Kellogg

3,040 3,600 3,500 67,200 445,000 501,000 417

413290

Government Gulch

near mouth

at Smelterville

1,410 1,420 41 187 47,400 48,200 3.9
Dissolved WWR Dissolved WWR Dissolved WWR

USGS

on Number

USGS

Station Name

Cadmium 

Annual Load 

(pounds)

Lead

Annual Load

(pounds)

Zinc

Annual Load

(pounds) Mean Daily Discharge

(ft3/s)

413445

Pine Creek

below Amy Gulch

near Pinehurst

155 158 170 1,340 47,400 44,800 197

413470 SFCDR near Pinehurst 6,790 7,920 5,920 166,000 945,000 1,190,000 687413500 CDR near Cataldo 6,920 9,860 10,800 200,000 1,040,000 1,300,000 3,050

413810 CDR at Rose Lake 7,570 8,790 15,800 246,000 1,200,000 1,500,000 3,040413860 CDR near Harrison 7,910 10,400 39,900 590,000 1,270,000 1,570,000 3,040

414500 St. Joe River at Calder 652 652 243 382 6,560 6,620 2,560

414900 St. Maries River near Santa 77 77 149 343 1,840 2,750 435419000 SR near Post Falls 3,700 4,940 6,190 51,300 1,060,000 1,080,000 7,530
Dissolved WWR Dissolved WWR Dissolved WWR

USGS

on Number

USGS

Station Name

Cadmium 

Annual Load 

(pounds)

Lead

Annual Load

(pounds)

Zinc

Annual Load

(pounds) Mean Daily Discharge

(ft3/s)

422500 SR at Spokane 3,940 4,310 8,860 45,300 875,000 989,000 7,530

433000 SR at Long Lake 1,960 2,110 7,150 25,000 577,000 764,000 9,240
Dissolved WWR Dissolved WWR Dissolved WWR

1000

NFCDR above

Shoshone Creek

near Prichard

0.047 0.047 0.048 0.21 0.92 2.37

1935

Prichard Creek

at mouth

at Prichard

0.12 0.16 0.32 4.5 28.6 34.9

3000 NFCDR at Enaville 0.033 0.041 0.15 1.65 5.47 11.63040

SFCDR above

Deadman Gulch

near Mullan

0.04 0.0630.31 4.65 7.71 15.9

3118 Canyon Creek near Burke 0.038 0.074 0.56 1.62 8.33 9.583123 Canyon Creek at Woodland Park 8.238.76 23.2 156 1,180 1,190

Zinc

Concentration (

μg/L)

w-weighted concentrations of dissolved and whole-water recoverable cadmium, lead,

easured during the 1999 water year at 24 water-quality stations within the Spokane River Basin,

Washington

ork Coeur d'Alene River; SFCDR, South Fork Coeur d'Alene River; CDR, Coeur d'Alene River; SR, Spokane River; 

er recoverable; USGS, U.S. Geological Survey; 

μg/L, micrograms per liter]

GS

Number

USGS

Station Name

Cadmium 

Concentration (

μg/L)

Lead

Concentration (

μg/L)
Dissolved WWR Dissolved WWR Dissolved WWR

Zinc

Concentration (

μg/L) 

GS

Number

USGS

Station Name

Cadmium 

Concentration (

μg/L)

Lead

Concentration (

μg/L)

3125

Canyon Creek

above mouth

at Wallace

13.315.325.6 236 1,840 2,050

3127

East Fork Ninemile

Creek above 

mouth near 

Blackcloud

33.3 33.5 63.1 183 5,580 5,630

3130

Ninemile Creek

above mouth

at Wallace

17.7 20.8 26 128 3,050 3,270

3140 Placer Creek at Wallace 0.046 0.05 0.26 1.02 1.42 3.223150 SFCDR at Silverton 5.21 5.11 7.17 79.9 772 7673190

Moon Creek

above mouth

at Elk Creek

0.37 0.40 0.37 3.29 73.8 75.5

3210

SFCDR at 

Elizabeth Park

near Kellogg

3.7 4.38 4.25 81.8 542 609

3290

Government Gulch

near mouth

at Smelterville

185 186 5.39 24.6 6,220 6,320
Dissolved WWR Dissolved WWR Dissolved WWR

Zinc

Concentration (

μg/L) 

GS

Number

USGS

Station Name

Cadmium 

Concentration (

μg/L)

Lead

Concentration (

μg/L)

3445

Pine Creek

below Amy Gulch

near Pinehurst

0.40 0.41 0.44 3.45 122 115

3470 SFCDR near Pinehurst 5.02 5.86 4.38 123 698 882

3500 CDR near Cataldo 1.15 1.64 1.80 33.3 173 216

3810 CDR at Rose Lake 1.26 1.47 2.6341 200 2513860 CDR near Harrison 1.32 1.74 6.65 98.4 212 2624500 St. Joe River at Calder 0.13 0.13 0.048 0.076 1.30 1.324900 St. Maries River near Santa 0.09 0.09 0.17 0.40 2.15 3.229000 SR near Post Falls 0.25 0.33 0.42 3.46 71.3 72.8
Dissolved WWR Dissolved WWR Dissolved WWR

Zinc

Concentration (

μg/L) 

GS

Number

USGS

Station Name

Cadmium 

Concentration (

μg/L)

Lead

Concentration (

μg/L)

2500 SR at Spokane 0.27 0.29 0.60 3.05 59 66.63000 SR at Long Lake 0.11 0.12 0.39 1.37 31.7 42
Total

Nitrogen

Dissolved

Ammonia

Total Organic

plus

Ammonia

Nitrogen

Dissolved

Nitrite

plus

Nitrate

Total

Phosphorus

Dissolved

Orthophosphorus

Mean Daily

Discharge

(ft3/s)

NFCDR above

Shoshone Creek

near Prichard

189,000 5,440 165,000 34,100 11,100 5,790 836

NFCDR at Enaville 527,000 12,400 434,000 110,000 58,200 15,200 2,240

SFCDR near Pinehurst 360,000 69,100 209,000 148,000 47,300 9,480 687

CDR near Harrison 767,000 86,700 547,000 314,000 107,000 15,000 3,040

St. Joe River at Calder 457,000 16,400 508,000 63,900 33,900 15,800 2,560

St. Maries River near Santa 100,000 16,900 90,400 11,900 11,600 5,040 435

SR near Post Falls 2,430,000 108,000 1,840,000 569,000 187,000 37,100 7,530

SR at Spokane 4,030,000 151,000 1,870,000 2,240,000 174,000 58,100 7,530

SR at Long Lake 13,000,000 377,000 3,850,000 11,000,000 677,000 464,000 9,240

USGS

Station Name

Annual load (pounds)

discharge and annual loads of nitrogen and phosphorus measured during the 1999 water year at nine

y stations within the Spokane River Basin, Idaho and Washington

k Coeur d'Alene River; SFCDR, South Fork Coeur d'Alene River; CDR, Coeur d'Alene River; 

ft3/s, cubic feet per second; USGS, U.S. Geological Survey]
Total

Nitrogen

Dissolved

Ammonia

Total Organic

plus

Ammonia 

Nitrogen

Dissolved

Nitrite

plus

Nitrate

Total

Phosphorus

Dissolved

Orthophosphorus

000

NFCDR above

Shoshone Creek

near Prichard

115 3 100 21 7 4

000 NFCDR at Enaville 119 3 98 25 13 3

470 SFCDR near Pinehurst 266 51 154 109 35 7860 CDR near Harrison 128 14 91 52 18 3500 St. Joe River at Calder 91 3 101 13 7 3900 St. Maries River near Santa 117 20 106 14 14 6000 SR near Post Falls 164 7 124 38 13 2

500 SR at Spokane 272 10 126 151 12 4

000 SR at Long Lake 713 21 212 604 37 26

ow-weighted concentrations of nitrogen and phosphorus measured during the 1999 water year at nine

ality stations within the Spokane River Basin, Idaho and Washington

 Fork Coeur d'Alene River; SFCDR, South Fork Coeur d'Alene River; CDR, Coeur d'Alene River; 

ver; USGS, U.S. Geological Survey; μg/L, micrograms per liter]

GS

on

ber

USGS

Station Name

Mean, flow-weighted concentration (μg/L)
Printed on recycled paper Printed on recycled paper