Delaware River Basin SPARROW Model Mary Chepiga Susan Colarullo Jeff Fischer US Geological Survey Delaware NAWQA

Today’s Talk The SPARROW model technique The SPARROW model technique Delaware River Basin SPARROW results for Total Nitrogen (TN) and Total Phosphorus (TP) for 2000 Delaware River Basin SPARROW results for Total Nitrogen (TN) and Total Phosphorus (TP) for 2000 SPARROW and water-quality monitoring SPARROW and water-quality monitoring

SPARROW* Model Concept *SPAtially Referenced Regression On Watershed Attributes Watershed Attributes

relates measured loads at monitoring stations to stream and land attributes SPARROW relates measured loads at monitoring stations to stream and land attributes Sources Stream Network Landscape Features Monitoring Data

Model predictions are made for every reach (not just monitored reaches) Load, yield, concentration Contribution from each source In-stream and reservoir losses Incremental and delivered loads for stream reaches, basins and sub-basins Statistical measures of uncertainty for predictors and predictions Stream reach Reach basin

Monitored/Calculated Loads

2000 Total Nitrogen Yields 97 sites 97 sites 50% are less than 700 kg/km 2 50% are less than 700 kg/km 2 10 % are greater than 2,000 kg/km 2 10 % are greater than 2,000 kg/km 2 Kg/Km 2 >2000 >700 and <2000 < 700 Major Stream

TP Loads Map here Map here 2000 Total Phosphorus Yields 110 sites 110 sites 50% are less than 25 kg/km 2 50% are less than 25 kg/km 2 10 % are greater than 75 kg/km 2 10 % are greater than 75 kg/km 2 Kg/Km 2 >75 >25 and <75 < 25 Major Stream

Total Nitrogen Total Phosphorus Atmospheric deposition Population Fertilizer applied to agricultural land Animal waste Diffuse (forest, urban, non- agricultural)* Water-holding capacity Precipitation Stream size Reservoir size Sources Land-to-Water Delivery Population Fertilizer applied to agricultural land Animal waste Diffuse (urban, non- agricultural)* Stream size* Reservoir size In-Stream Transport

Delaware River Basin SPARROW Model Results

DRB SPPARROW Results DRB SPPARROW Results for entire basin Total Nitrogen (TN) 57.8 million kg Total Phosphorus (TP) 4.0 million kg Atmospheric Deposition 14.5 kg Population 11.6 kg Fertilizer 12.7 kg Waste 18.4 kg Diffuse* 0.6 kg Population 2.5 kg Fertilizer 0.5 kg Waste 0.7 kg Diffuse 0.3 kg

Total Nitrogen load, in kilograms per year Total Nitrogen 2000 Total Loads < 1,000 1, ,000 5,001 – 50,000 50,001 – 500,000 > 500,000

Total Nitrogen Incremental Load, in kilograms per year Total Nitrogen 2000 Incremental Loads < – 1,000 1,000 – 10,000 > 10,000

Total Nitrogen Incremental Yield in kg per km 2 per year Total Nitrogen 2000 Incremental Yields < 1,000 1,000 – 2,000 2,001 – 4,000 4,001 – 6,000 > 6,000

TN Major Sources TP Major Sources Major Sources Atmospheric Deposition Diffuse Fertilizer Waste Population

Total Nitrogen by Source and Basin

Total Nitrogen Delivered to Estuary (39 Mkg)

Nitrogen Incremental Yield by Source and AMNET Basin NONESEVEREMODERATE IMPAIRMENT

SPARROW and Water-Quality Monitoring

SPARROW TN Errors LowestHighest Error Evaluation Model explains ~90 to 95% of spatial variability in loads Prediction errors for stream reaches are typically +/- 5 to 60% of load Generally half of the independent variables are non-significant

Delaware River Basin SPARROW Model Points of Contact Mary Chepiga Susan Colarullo Jeff Fischer US Geological Survey Delaware NAWQA

Load Sources Land-to-water delivery Instream decay Error SPARROW Budget Equation Spatial non-linear regression Adjusts land and stream delivery factors on the basis of basin-wide statistical relationships Minimizes errors at monitoring sites

Total Phosphorus Load, in kilograms per year Total Phosphorus 2000 Total Loads < 1,000 1, ,000 10,001 – 20,000 20,001 – 400,000 > 400,000

Total Phosphorus Incremental Load, in kilograms per year Total Phosphorus 2000 Incremental Loads < – 1,000 1,001 – 10,000 > 10,000

TP Total Loads TPIncrementalLoads

Total Phosphorus Incremental Yield, in kg per km 2 per year Total Phosphorus 2000 Incremental Yields < – – 10 > 10

Data Sources

Data Sources (cont’d)