U.S. Department of the InteriorU.S. Geological Survey

USGS Fact Sheet 038-99December 1999

OregonColumbia River Contaminants

The Columbia River is a prizednatural resource of the Pacific North-west. The river is used for navigation,hydroelectric power generation,outdoor recreation, and also hasvarious heavy industries along itsbanks.

As a result of urbanization, agricul-tural development, and industrializa-tion throughout the basin, fish,wildlife, and human populations inand near the river are exposed tocontaminants from runoff and atmo-spheric deposition. Industrial pollut-ants and agricultural pesticides havebeen associated with abnormalreproductive organs in river otters anddecreased productivity of bald eagles.These and other contaminants alsoare suspected of being detrimental toseveral additional species. To assessthe overall health of the ColumbiaRiver ecosystem, scientists from theUSGS Forest and Rangeland Ecosys-tem Science Center, the USGSOregon District, the U.S. Fish andWildlife Service, and other Federaland State agencies are evaluatinglevels of contaminants in water andsediments and monitoring wildlife forcontaminant accumulation and healtheffects (fig. 1).

Organic contaminants, even in lowconcentrations, can accumulate in thefatty tissues of animals and causehealth problems. Such very lowconcentrations are not measurableusing conventional sampling meth-ods, so USGS scientists are using anew technology—semipermeable-membrane devices (SPMD’s)—tomeasure contaminants in the Colum-

bia River Basin (fig. 2). Each SPMDconsists of a thin membrane filledwith a fatty compound. The SPMD isplaced in the river, where it accumu-lates organic contaminants and thusacts as a “virtual fish.”

To monitor the effects of contami-nants on wildlife, several species offish, more than 250 nesting pairs ofospreys (fish-eating birds), and riverotters from the Columbia and Willa-mette Rivers are being studied toevaluate accumulation of contami-nants in fatty tissues, general health,and productivity.

The use of advanced samplingtechniques such as the SPMD,

coupled with tissue analysis ofwildlife in the Columbia River Basin,will enable an unprecedented under-standing of the effects of manmadeorganic contaminants on a riverecosystem.

Potential Geologic Hazards

Volcanoes

Volcanic eruptions and large earth-quakes have affected the PacificNorthwest in the past and representfuture hazards as well. USGS scien-tists recently completed severalproducts designed to inform publicofficials and the public of volcanohazards. Volcano-hazard assessmentreports, with accompanying hazard-zone maps, were released for theNewberry and Crater Lake areas(Volcano Hazards at NewberryVolcano, Oregon: U.S. GeologicalSurvey Open-File Report 97-513, andVolcano and Earthquake Hazards inthe Crater Lake Region, Oregon: U.S.Geological Survey Open-File Report97-487). Both reports describe thekinds of eruptions that have occurredin the past and the areas that might beaffected by future eruptions. Thereports also provide preliminaryestimates of the probability of futureevents, based on the frequency of pastactivity. In addition, the Crater Lakereport evaluates earthquake hazardsin that region.

A new video, “At Risk: VolcanoHazards from Mount Hood, Oregon,”uses footage of recent eruptions atsimilar volcanoes around the world toprovide a glimpse of the types ofevents that might occur during future

Figure 1. Otters and other wildlife inthe Columbia River Basin are exposedto waterborne contaminants.

Figure 2. USGS hydrologists prepareto deploy a semipermeable-membrane sampling device in theColumbia River.

science for a changing world

eruptions of Mount Hood, theirpotential effects on the area aroundthe volcano, and areas at greatest risk.The video is available from theNorthwest Interpretive Association,3029 Spirit Lake Highway, CastleRock, WA 98611, ph: (360) 274-2127.

Earthquakes

Crustal earthquakes are anothergeologic hazard that could affect thepopulated regions of western Oregon.Although crustal earthquakes arerelatively rare on any given fault,faults exist beneath the most heavilypopulated regions of western Oregonand Washington, and a quake on anyone of them could have devastatingconsequences.

Much of western Oregon is underlainby shallow, slightly magnetic volca-nic rocks. By measuring the Earth’s

magnetic field near the ground,USGS scientists are learning aboutfaults that cut and offset the volcanicbasement rocks. These measurementsare made with a magnetic sensorcalled a magnetometer, which isusually attached to a low-flyingairplane.

The USGS has been acquiringaeromagnetic data from the CoastRange of western Oregon and Wash-ington to help identify geologichazards (fig. 3). For example, aero-magnetic anomalies along the MountAngel Fault (MAF), the likely sourceof the magnitude 5.6 Scotts Millsearthquake in 1997, reveal its locationeven where it is concealed beneathvalley deposits. These studies alsoindicate that the Mount Angel Fault isconnected with the Gales Creek Fault(GCF). Determining whether theGales Creek-Mount Angel Fault iscapable of producing a large earth-quake will require additional studies.

USGS Maps

Northwest Forest Plan

To facilitate implementation of theNorthwest Forest Plan, the USGS,other Federal agencies, State agen-cies, counties, and private organiza-tions initiated Baseline97, a project toconstruct a statewide, 1:24,000-scaledigital base map coverage of Oregon.The coverage is composed of DigitalLine Graphs (transportation, streams,elevation contours, boundaries, andPublic Land Survey data); DigitalElevation Models (DEM’s); andDigital Raster Graphics (DRG’s)(scanned images of USGS topo-graphic maps) (fig. 4).

The Baseline97 coverage is used forspotted owl and aquatic-habitatmanagement. The Regional Ecosys-tem Office is using Baseline97 data ina Federal-State effort to delineateOregon watershed boundaries. UsingDRG’s as a backdrop, the Bureau ofLand Management (BLM) OregonState Office is digitizing boundariesfor this watershed-delineation project.

Salmon Conservation

Through the Oregon Plan and theCoastal Salmon Restoration Initiative,the State seeks to restore salmon andtrout resources to sustainable levelswhile still maintaining economic andother benefits. The Willamette River,a designated American HeritageRiver, is a focus of the Oregon Planbecause of the relation between itswater quality and affected salmonpopulations.

River-flow modeling is an integralpart of the Oregon plan. The USGS,other Federal agencies, the Gover-nor’s Watershed Enhancement Board(through the Coastal LandscapeAnalysis and Modeling Study group),Polk County, the Southwest Provin-cial Interagency Executive Commit-

Figure 3. The colors on these aeromagnetic maps of the Portland-Salem areaindicate the intensity of the magnetic field near the ground surface, which inturn reflects the magnetic properties of underlying volcanic rocks. Both mapsshow the same magnetic data; the map on the right highlights interpretedgeologic structures. The dotted lines on the map show the location of severalmagnetic linears, some of which are caused by faults. These magnetic data arebeing used in conjunction with geologic mapping and other earth-sciencestudies to characterize faults in the northern Willamette Valley. Faults: MAF,Mount Angel Fault; GCF, Gales Creek Fault; OF, Oatfield Fault; EBF, East BankFault; CMF, Canby-Molalla Fault. KM, kilometer; nT, nanotesla.

EEBBFF

1400 nT

KM25

OOFFMM

AAFF

GGCC

FF

CCMM

FF

123° 122°30'123° 122°30'

45°

45°30'

VancouverPPorortlandtland

SalemSalem

Oregon

tee, and the State Elevation Commit-tee are creating an elevation data setfor western Oregon consisting of 10-meter-resolution digital elevationmodels (DEM’s). DEM’s are well-suited for certain surface-modelingapplications. These DEM’s accuratelydepict stream gradients and networksin river basins.

Landslide-Potential Assessments

DEM’s also are used in Oregon toinvestigate landslide potential.Scientists at Oregon State Universityand the Oregon Department ofForestry utilize DEM data for slopemodels used to produce maps thatspecify the relative risk of landslidesthroughout western Oregon.

High Priority Digital Data Program

Digital orthophoto quadrangle maps(DOQ’s) are scanned aerial photo-

graphs in which the distortions anddisplacements caused by cameraorientation and terrain are removed.DOQ’s produced by the USGS coverthe area represented by one-quarter ofa standard USGS 7.5-minute,1:24,000-scale topographic map.DOQ’s have many applications. Forexample, the BLM uses DOQ’s tocheck the accuracy of stream androad locations on maps and to digitizeadditional features. The Departmentof Agriculture’s Natural ResourcesConservation Service and the FarmServices Agency use DOQ’s for soilsurveys and to develop conservationand crop plans with farmers. DOQ’sare available through USGS EarthScience Information Centers and theGlobal Land Information System Website at http://edcwww.cr.usgs.gov/webglis/.

Ground-Water Studies

Water Supply in the Upper DeschutesBasin

USGS ground-water investigationsare helping State and local agenciesdeal with rapid growth in the 4,500square-mile upper Deschutes Basin,one of the fastest growing regions inOregon. Ground water must supplythe water needs for all new develop-ment in this region because, for mostuses, surface-water resources are fullyappropriated. The ground-watersystem is hydraulically connected tostreams, and ground-water use can,therefore, reduce streamflow. Re-duced streamflow is a concernbecause of its possibly adverse effecton recreation and on fish that migrateupstream to breed.

Data collection and analysis by theUSGS, in cooperation with the Stateof Oregon, local government agen-cies, and the Confederated Tribes ofthe Warm Springs Reservation ofOregon, has provided quantitativeinformation about the connection

between ground water and stream-flow. A computer model developedduring this study provides the abilityto estimate the effects of developmentscenarios on streamflow. This abilityis intended to help resource managersprotect streamflow while providingsufficient ground water to accommo-date the predicted growth in theDeschutes Basin.

Another issue in the Deschutes Basinis the hundreds of water wells thatcould be affected by the sealing ofleaking irrigation canals. Unlinedcanals in the basin lose about 300,000acre-feet of water annually throughleakage, and efforts are underway toline the canals to reduce this loss.Most of the water lost from canalspercolates to the ground-watersystem, artificially recharging aqui-fers and raising water levels. Manyresidents have come to depend on thissource of water to supply their wells,and lining canals will likely causesome wells to go dry. The USGSupper Deschutes Basin ground-waterstudy will provide water managersand well owners with information onthe likely effects of canal lining.

Arsenic in Ground Water of the SouthernWillamette Valley

Data from USGS investigations arehelping State water-resources andhealth officials determine the extentof arsenic contamination in groundwater in the southern WillametteValley, a densely populated region(fig. 5). A recent study found that thearsenic concentrations in water frommany wells exceeds the U.S. Envi-ronmental Protection Agency maxi-mum contaminant levels for drinkingwater, and the concentration in waterfrom one-fifth of the wells sampledexceeded the World Health Organiza-tion standard. The study results willenable health officials to identifyareas where well owners are at riskand should test and, possibly, treat

Figure 4. Digital Raster Graphics(DRG’s) are used by the USGS toproduce other map products or toassess the completeness of digitaldata from outside sources.

Printed on recycled paper

USGS State RepresentativeUSGS office locations10615 S.E. Cherry Blossom Dr.Portland OR 97216(503) 251-3200FAX (503) 251-3470

USGS Home Pagehttp://www.usgs.govReports and products1-888-ASK-USGS

their drinking water. A report detail-ing the results of the study, “Arsenicin Ground Water of the WillametteBasin, Oregon,” Water-ResourcesInvestigations Report 98-4205, canbe accessed online at http://oregon.usgs.gov/pubs_dir/online_list.html.

Effects of Tern Predation onJuvenile Salmon and Trout

The Oregon Plan is an unprecedentedState effort to restore decliningsalmon and trout populations. Insupport of the initiative, USGSbiologists at the Oregon CooperativeFish and Wildlife Research Unit arestudying predation by Caspian ternson young steelhead, coho salmon,and chinook salmon passing throughthe Columbia River estuary (fig. 6).Breeding terns from a large colony onRice Island consume an estimated 6to 25 percent of juvenile salmon andtrout leaving the Columbia-SnakeRiver Basin each year.

While continuing to study ternpopulation trends and factors thatmay influence predation, biologistsalso are testing methods of reducingfish losses. Studies completed in1998 suggested that moving the terncolony to another island might helplarger numbers of fish reach theocean.

Cooperative Forest EcosystemResearch Program

The Northwest Forest Plan, adoptedin 1994, set new directions for forestecosystem management in the Pacific

Northwest. In support of the plan, theUSGS, the BLM, Oregon StateUniversity, and the Oregon Depart-ment of Forestry formed the Coop-erative Forest Ecosystem ResearchProgram. The major goals of theProgram are to conduct research toprovide forest managers with newinformation to evaluate current andproposed practices for managementof forest ecosystems and to facilitatedevelopment of sustainable forestpractices. An integral part of theProgram’s mission is to work closelywith resource managers, researchers,and decisionmakers to develop andconvey information needed toimplement ecosystem-based manage-ment.

The USGS has 149 employees in Oregon

Corvallis

Eugene

Medford

PortlandSalem

Summer Lake

Klamath Falls

Figure 6. Predation of migratingjuvenile salmonid fishes by coloniesof Caspian terns adversely affectssalmon and steelhead recoveryefforts.

Figure 5. High concentrations ofarsenic in wells and springs (shownby red circles) are widespread in theWillamette Valley; the highest knownconcentrations are in the south.

COLUMBIARIVER

WIL

LA

ME

TT

E

RIV

ER

Portland

Eugene

R A

N G

EC

O A

S T

R A

N G

EC

A S

C A

D E

44

45

122

123

20

200

0 MILES

KILOMETERS

Salem

OREGON

WillametteBasin