Relating Surface Water Nutrients in the Pacific Northwest to Watershed Attributes Using the USGS...

Relating Surface Water Nutrients in the Pacific Northwest to

Watershed Attributes Using the USGS SPARROW Model

Daniel Wise, HydrologistUS Geological SurveyPortland, OR

USGS SPARROW Model

• SPAtially Referenced Regression On Watershed attributes.

• SPARROW is a powerful tool for informing water-quality management decisions.

SPARROW Model Description

• SPARROW relates water-quality measurements to watershed characteristics, including contaminant sources and factors influencing terrestrial and stream transport.

• The model uses a process-based mass balance of load in combination with a spatially explicit nonlinear multiple regression on watershed attributes.

SPARROW Model Description

Point Sources

Delivery to Waterways

Instream Processing

Landscape Loading

Export

SettlingBiological Uptake

Overland FlowSubsurface Flow

SPARROW is Process-Based

Nonpoint Sources

SPARROW Model Description

SPARROWWater-quality monitoring data

Regional geospatial data

Region-wide water quality interpretation and predictions

Hydrologic network data

SPARROW is Spatially Explicit

SPARROW Model Description

SPARROW is Spatially Explicit

SPARROW Model DescriptionThe fundamental componentof the SPARROW model isthe stream reach and itsassociated incrementalcatchment.

Reaches begin at all streamconfluences and at thelocations of calibrationsites

An incremental catchment is the area that drains directlyto a reach without passingthrough another reach

SPARROW Model Description

Detailed predictions made for every stream reach:

1) Mean annual load (kg/yr)

2) Mean annual conc. (mg/L)

3) Source contribution to load

SPARROW Model Description

Pacific Nortwest12,039 individual reachesand associated incrementalcatchments

Willamette River Basin755 individual reaches andassociated incrementalcatchments

U.S.G.S. SPARROW Nutrient Models

PNW Study Area

Using SPARROW to Model Surface-Water Nutrients

Sources of Nutrients

Nutrient loading to the land

Background Sources

Sources of Nutrients

Nutrient loading to the land

Background Sources

Urbanization

Sources of Nutrients

Nutrient loading to the land

Background Sources

Urbanization

Agriculture

How can SPARROW results be used?

• Predicting water-quality conditions where no water-quality data are available

• Predicting contaminant delivery by source type and location

• Predicting changes in water-quality conditions under different management scenarios

• Designing water-quality monitoring programs

How can SPARROW results be used?

• Predicting water-quality conditions where no water-quality data are available

• Predicting contaminant delivery by source type and location

• Predicting changes in water-quality conditions under different management scenarios

• Designing water-quality monitoring programs

Largest Sources of Total Nitrogen Load Generated within Incremental Catchments (2002)

Largest Sources of Total Nitrogen Load Generated within Incremental Catchments (2002)

Contribution from Different Sources to Total Nitrogen Load Discharged from the Willamette Basin (2002)

Source Category

Source Contribution

(percent)

Point Sources 30.0

Farm Fertilizer 27.2

Forest Land 12.9

Livestock Manure

10.9

Developed Land 9.3

Red Alder Trees

6.8

Atmospheric 2.8

How can SPARROW results be used?

• Predicting water-quality conditions where no water-quality data are available

• Predicting contaminant delivery by source type and location

• Predicting changes in water-quality conditions under different management scenarios

• Designing water-quality monitoring programs

Yakima River Management Scenarios

50% Reduction in Upstream Point Source Loading to Streams

Adjusted TP Load 186 tons/yr

(-26 tons/yr)

50% Reduction in Upstream Fertilizer and Manure Loading to Land

Adjusted TP Load 196 tons/yr

(-16 tons/yr)

Yakima River

(212 tons TP/yr)

Source Contribution

(percent)

Geologic Material 53.6

Farm Fertilizer and Livestock Manure 16.5

Point Sources 24.4

Developed Land 5.5

SPARROW Outreach and Communication

• Publication of article in Journal of the American Water Resources Association (August, 2011)

Surface-Water Nutrient Conditions and Sources in the United States Pacific NorthwestDaniel R. Wise1 and Henry M. Johnson2

SPARROW Outreach and Communication

• Web-based Decision Support System

• Display detailed model results

• Run water-quality management scenarios

• Identify major players (sources and areas)

PNW SPARROW Next Phase• Migration from RF1 to NHD Stream Network

Willamette River BasinRF1 NHD755 catchments 10,198

catchments

PNW SPARROW Next Phase

Point SourcesWWTP’sFish HatcheriesIndustrial Facilities

New or Refined Source

Nonpoint SourcesFarm FertilizerDairies and FeedlotsGrazing CattleOther LivestockNonsewered PopulationLand-Applied WastewaterBiosolids ApplicationAtmospheric N DepositionGeologic PhosphorusMarine-Derived Nutrients

• Improved Nutrient Source Estimates

SPARROW Input Geoprocessing Example

Landscape Nutrient Loadings from Dairies and Feedlots

Use available information:USDA agricultural census

(county level)State depts of agricultureBusiness directoriesNational landcover data base

Confined cattle waste distributedto farmland based on proximity todairies and feedlots.

SPARROW Input Geoprocessing Example

Landscape nutrient loadings fromconfined cattle summarized foreach SPARROW incrementalcatchment.

Questions?

Contact:

Daniel Wise: USGS OR Water Science Center503-251-3213; dawise@usgs.gov