U.S. Department of the Interior

U.S. Geological Survey

USGS Fact Sheet 038-99

December 1999

Oregon

Columbia River Contaminants

The Columbia River is a prized

natural resource of the Pacific Northwest. The river is used for navigation,

hydroelectric power generation,

outdoor recreation, and also has

various heavy industries along its

banks.

As a result of urbanization, agricultural development, and industrialization throughout the basin, fish,

wildlife, and human populations in

and near the river are exposed to

contaminants from runoff and atmospheric deposition. Industrial pollutants and agricultural pesticides have

been associated with abnormal

reproductive organs in river otters and

decreased productivity of bald eagles.

These and other contaminants also

are suspected of being detrimental to

several additional species. To assess

the overall health of the Columbia

River ecosystem, scientists from the

USGS Forest and Rangeland Ecosystem Science Center, the USGS

Oregon District, the U.S. Fish and

Wildlife Service, and other Federal

and State agencies are evaluating

levels of contaminants in water and

sediments and monitoring wildlife for

contaminant accumulation and health

effects (fig. 1).

Organic contaminants, even in low

concentrations, can accumulate in the

fatty tissues of animals and cause

health problems. Such very low

concentrations are not measurable

using conventional sampling methods, so USGS scientists are using a

new technology—semipermeablemembrane devices (SPMD’s)—to

measure contaminants in the Columbia River Basin (fig. 2). Each SPMD

consists of a thin membrane filled

with a fatty compound. The SPMD is

placed in the river, where it accumulates organic contaminants and thus

acts as a “virtual fish.”

To monitor the effects of contaminants on wildlife, several species of

fish, more than 250 nesting pairs of

ospreys (fish-eating birds), and river

otters from the Columbia and Willamette Rivers are being studied to

evaluate accumulation of contaminants in fatty tissues, general health,

and productivity.

The use of advanced sampling

techniques such as the SPMD,

coupled with tissue analysis of

wildlife in the Columbia River Basin,

will enable an unprecedented understanding of the effects of manmade

organic contaminants on a river

ecosystem.

Potential Geologic Hazards

Volcanoes

Volcanic eruptions and large earthquakes have affected the Pacific

Northwest in the past and represent

future hazards as well. USGS scientists recently completed several

products designed to inform public

officials and the public of volcano

hazards. Volcano-hazard assessment

reports, with accompanying hazardzone maps, were released for the

Newberry and Crater Lake areas

(Volcano Hazards at Newberry

Volcano, Oregon: U.S. Geological

Survey Open-File Report 97-513, and

Volcano and Earthquake Hazards in

the Crater Lake Region, Oregon: U.S.

Geological Survey Open-File Report

97-487). Both reports describe the

kinds of eruptions that have occurred

in the past and the areas that might be

affected by future eruptions. The

reports also provide preliminary

estimates of the probability of future

events, based on the frequency of past

activity. In addition, the Crater Lake

report evaluates earthquake hazards

in that region.

A new video, “At Risk: Volcano

Hazards from Mount Hood, Oregon,”

uses footage of recent eruptions at

similar volcanoes around the world to

provide a glimpse of the types of

events that might occur during future

Figure 1. Otters and other wildlife in

the Columbia River Basin are exposed

to waterborne contaminants.

Figure 2. USGS hydrologists prepare

to deploy a semipermeablemembrane sampling device in the

Columbia River.
science for a changing world

eruptions of Mount Hood, their

potential effects on the area around

the volcano, and areas at greatest risk.

The video is available from the

Northwest Interpretive Association,

3029 Spirit Lake Highway, Castle

Rock, WA 98611, ph: (360) 274-

2127.

Earthquakes

Crustal earthquakes are another

geologic hazard that could affect the

populated regions of western Oregon.

Although crustal earthquakes are

relatively rare on any given fault,

faults exist beneath the most heavily

populated regions of western Oregon

and Washington, and a quake on any

one of them could have devastating

consequences.

Much of western Oregon is underlain

by shallow, slightly magnetic volcanic rocks. By measuring the Earth’s

magnetic field near the ground,

USGS scientists are learning about

faults that cut and offset the volcanic

basement rocks. These measurements

are made with a magnetic sensor

called a magnetometer, which is

usually attached to a low-flying

airplane.

The USGS has been acquiring

aeromagnetic data from the Coast

Range of western Oregon and Washington to help identify geologic

hazards (fig. 3). For example, aeromagnetic anomalies along the Mount

Angel Fault (MAF), the likely source

of the magnitude 5.6 Scotts Mills

earthquake in 1997, reveal its location

even where it is concealed beneath

valley deposits. These studies also

indicate that the Mount Angel Fault is

connected with the Gales Creek Fault

(GCF). Determining whether the

Gales Creek-Mount Angel Fault is

capable of producing a large earthquake will require additional studies.

USGS Maps

Northwest Forest Plan

To facilitate implementation of the

Northwest Forest Plan, the USGS,

other Federal agencies, State agencies, counties, and private organizations initiated Baseline97, a project to

construct a statewide, 1:24,000-scale

digital base map coverage of Oregon.

The coverage is composed of Digital

Line Graphs (transportation, streams,

elevation contours, boundaries, and

Public Land Survey data); Digital

Elevation Models (DEM’s); and

Digital Raster Graphics (DRG’s)

(scanned images of USGS topographic maps) (fig. 4).

The Baseline97 coverage is used for

spotted owl and aquatic-habitat

management. The Regional Ecosystem Office is using Baseline97 data in

a Federal-State effort to delineate

Oregon watershed boundaries. Using

DRG’s as a backdrop, the Bureau of

Land Management (BLM) Oregon

State Office is digitizing boundaries

for this watershed-delineation project.

Salmon Conservation

Through the Oregon Plan and the

Coastal Salmon Restoration Initiative,

the State seeks to restore salmon and

trout resources to sustainable levels

while still maintaining economic and

other benefits. The Willamette River,

a designated American Heritage

River, is a focus of the Oregon Plan

because of the relation between its

water quality and affected salmon

populations.

River-flow modeling is an integral

part of the Oregon plan. The USGS,

other Federal agencies, the Governor’s Watershed Enhancement Board

(through the Coastal Landscape

Analysis and Modeling Study group),

Polk County, the Southwest Provincial Interagency Executive CommitFigure 3. The colors on these aeromagnetic maps of the Portland-Salem area

indicate the intensity of the magnetic field near the ground surface, which in

turn reflects the magnetic properties of underlying volcanic rocks. Both maps

show the same magnetic data; the map on the right highlights interpreted

geologic structures. The dotted lines on the map show the location of several

magnetic linears, some of which are caused by faults. These magnetic data are

being used in conjunction with geologic mapping and other earth-science

studies to characterize faults in the northern Willamette Valley. Faults: MAF,

Mount Angel Fault; GCF, Gales Creek Fault; OF, Oatfield Fault; EBF, East Bank

Fault; CMF, Canby-Molalla Fault. KM, kilometer; nT, nanotesla.

EBF

 1400 nT

25 KM

OF

MAF

GCF

CMF

123° 122°30' 123° 122°30'

45°

45°30'

Vancouver

Portland

Salem
Oregon

tee, and the State Elevation Committee are creating an elevation data set

for western Oregon consisting of 10-

meter-resolution digital elevation

models (DEM’s). DEM’s are wellsuited for certain surface-modeling

applications. These DEM’s accurately

depict stream gradients and networks

in river basins.

Landslide-Potential Assessments

DEM’s also are used in Oregon to

investigate landslide potential.

Scientists at Oregon State University

and the Oregon Department of

Forestry utilize DEM data for slope

models used to produce maps that

specify the relative risk of landslides

throughout western Oregon.

High Priority Digital Data Program

Digital orthophoto quadrangle maps

(DOQ’s) are scanned aerial photographs in which the distortions and

displacements caused by camera

orientation and terrain are removed.

DOQ’s produced by the USGS cover

the area represented by one-quarter of

a standard USGS 7.5-minute,

1:24,000-scale topographic map.

DOQ’s have many applications. For

example, the BLM uses DOQ’s to

check the accuracy of stream and

road locations on maps and to digitize

additional features. The Department

of Agriculture’s Natural Resources

Conservation Service and the Farm

Services Agency use DOQ’s for soil

surveys and to develop conservation

and crop plans with farmers. DOQ’s

are available through USGS Earth

Science Information Centers and the

Global Land Information System Web

site at http://edcwww.cr.usgs.

gov/webglis/.

Ground-Water Studies

Water Supply in the Upper Deschutes

Basin

USGS ground-water investigations

are helping State and local agencies

deal with rapid growth in the 4,500

square-mile upper Deschutes Basin,

one of the fastest growing regions in

Oregon. Ground water must supply

the water needs for all new development in this region because, for most

uses, surface-water resources are fully

appropriated. The ground-water

system is hydraulically connected to

streams, and ground-water use can,

therefore, reduce streamflow. Reduced streamflow is a concern

because of its possibly adverse effect

on recreation and on fish that migrate

upstream to breed.

Data collection and analysis by the

USGS, in cooperation with the State

of Oregon, local government agencies, and the Confederated Tribes of

the Warm Springs Reservation of

Oregon, has provided quantitative

information about the connection

between ground water and streamflow. A computer model developed

during this study provides the ability

to estimate the effects of development

scenarios on streamflow. This ability

is intended to help resource managers

protect streamflow while providing

sufficient ground water to accommodate the predicted growth in the

Deschutes Basin.

Another issue in the Deschutes Basin

is the hundreds of water wells that

could be affected by the sealing of

leaking irrigation canals. Unlined

canals in the basin lose about 300,000

acre-feet of water annually through

leakage, and efforts are underway to

line the canals to reduce this loss.

Most of the water lost from canals

percolates to the ground-water

system, artificially recharging aquifers and raising water levels. Many

residents have come to depend on this

source of water to supply their wells,

and lining canals will likely cause

some wells to go dry. The USGS

upper Deschutes Basin ground-water

study will provide water managers

and well owners with information on

the likely effects of canal lining.

Arsenic in Ground Water of the Southern

Willamette Valley

Data from USGS investigations are

helping State water-resources and

health officials determine the extent

of arsenic contamination in ground

water in the southern Willamette

Valley, a densely populated region

(fig. 5). A recent study found that the

arsenic concentrations in water from

many wells exceeds the U.S. Environmental Protection Agency maximum contaminant levels for drinking

water, and the concentration in water

from one-fifth of the wells sampled

exceeded the World Health Organization standard. The study results will

enable health officials to identify

areas where well owners are at risk

and should test and, possibly, treat

Figure 4. Digital Raster Graphics

(DRG’s) are used by the USGS to

produce other map products or to

assess the completeness of digital

data from outside sources.
Printed on recycled paper

USGS office locations USGS State Representative

10615 S.E. Cherry Blossom Dr.

Portland OR 97216

(503) 251-3200

FAX (503) 251-3470

USGS Home Page

http://www.usgs.gov

Reports and products

1-888-ASK-USGS

their drinking water. A report detailing the results of the study, “Arsenic

in Ground Water of the Willamette

Basin, Oregon,” Water-Resources

Investigations Report 98-4205, can

be accessed online at http://

oregon.usgs.gov/pubs_dir/

online_list.html.

Effects of Tern Predation on

Juvenile Salmon and Trout

The Oregon Plan is an unprecedented

State effort to restore declining

salmon and trout populations. In

support of the initiative, USGS

biologists at the Oregon Cooperative

Fish and Wildlife Research Unit are

studying predation by Caspian terns

on young steelhead, coho salmon,

and chinook salmon passing through

the Columbia River estuary (fig. 6).

Breeding terns from a large colony on

Rice Island consume an estimated 6

to 25 percent of juvenile salmon and

trout leaving the Columbia-Snake

River Basin each year.

While continuing to study tern

population trends and factors that

may influence predation, biologists

also are testing methods of reducing

fish losses. Studies completed in

1998 suggested that moving the tern

colony to another island might help

larger numbers of fish reach the

ocean.

Cooperative Forest Ecosystem

Research Program

The Northwest Forest Plan, adopted

in 1994, set new directions for forest

ecosystem management in the Pacific

Northwest. In support of the plan, the

USGS, the BLM, Oregon State

University, and the Oregon Department of Forestry formed the Cooperative Forest Ecosystem Research

Program. The major goals of the

Program are to conduct research to

provide forest managers with new

information to evaluate current and

proposed practices for management

of forest ecosystems and to facilitate

development of sustainable forest

practices. An integral part of the

Program’s mission is to work closely

with resource managers, researchers,

and decisionmakers to develop and

convey information needed to

implement ecosystem-based management.

The USGS has 149 employees 

in Oregon

Corvallis

Eugene

Medford

Portland

Salem

Summer Lake

Klamath Falls

Figure 6. Predation of migrating

juvenile salmonid fishes by colonies

of Caspian terns adversely affects

salmon and steelhead recovery

efforts.

Figure 5. High concentrations of

arsenic in wells and springs (shown

by red circles) are widespread in the

Willamette Valley; the highest known

concentrations are in the south.

COLUMBIA RIVER

WILLA

METTE

RIVER

Portland

Eugene

R A N G E

C O A S T

R A N G E

C A S C A D E

44

45

122

123

20

0 20

0 MILES

KILOMETERS

Salem

OREGON

Willamette

Basin