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SPARROW Surface Water Quality Workshop October 29-31, 2002 Reston, Virginia Section 5. Comparison of GIS Approaches, Dat

SPARROW Surface Water Quality Workshop October 29-31, 2002 Reston, Virginia Section 5. Comparison of GIS Approaches, Data Sources and Management. Difficult. Moderate. Few Problems. Network Approach Comparison. RF1 DEM NHD Attributes Topology Scale/Density Watersheds Availability.

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SPARROW Surface Water Quality Workshop October 29-31, 2002 Reston, Virginia Section 5. Comparison of GIS Approaches, Dat

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  1. SPARROW Surface Water Quality Workshop • October 29-31, 2002 • Reston, Virginia • Section 5. Comparison of GIS Approaches, Data Sources and Management

  2. Difficult Moderate Few Problems Network Approach Comparison RF1 DEM NHD Attributes Topology Scale/Density Watersheds Availability 100K 24K

  3. GIS Arc/Info & ArcView SPARROW SAS & Fortran Nutrient Sources Modeling Process Network Based on Stream Reaches and Watersheds Delivery Predictions and Diagnostics Estimated Loads by Stream Reach Incremental, Delivered, and Total All Sources Land Use Fertilizer Atmospheric Deposition Point Source Manure

  4. Nutrient Source Data • Nutrient Sources • Atmospheric Deposition (NADP) • Septic Systems (Census) • Point Sources (PCS) • Fertilizer (Ag Census) • Manure (NASS, Ag Census) • Land Use(MRLC / NLCD and Census) • Urban • Agricultural

  5. Agricultural Sources • Fertilizer • Sales by state • Disaggregated by county expenditures • Application rates (from state) by land use (CB) • Hightill, Lowtill, Pasture, Hayland • Manure • Animal census by county • Estimate nutrient generation based on animal unit • Some counties grouped • Application rates by land use (CB) • Hightill, Lowtill, Pasture, Hayland

  6. Delivery Data • Land-Water Delivery Factors • Slope (from DEM) • Soil (STATSCO) • Precipitation (NCDC) • Temperature (HCN) • Physiography/Geology (state 1:250,000) • Density (RF1, DEM, NHD) • Land Use/Cover(NLCD) • Forest area • Wetland area

  7. Data Availibility • Network Related • NHD http://nhd.usgs.gov/index.html • NED http://gisdata.usgs.net/ned/ • EDNA http://edcnts12.cr.usgs.gov/ned-h/ • USEPA RF1 http://www.epa.gov/nsdi/projects/rf1_meta.html • ERF1-2 http://water.usgs.gov/lookup/getspatial?erf1-2 • USEPA STORET http://www.epa.gov/storet/ • HUC Boundary http://www.ftw.nrcs.usda.gov/huc_data.html • NWIS WEB http://waterdata.usgs.gov/usa/nwis/nwis • RESERVOIRS http://water.usgs.gov/lookup/getspatial?reservoir

  8. Data Availibility • Source • Agriculture http://www.nass.usda.gov/census/ • NASS http://www.usda.gov/nass/ • PCS http://www.epa.gov/enviro/html/pcs/pcs_query_java.html • Sewer Population http://www.census.gov/geo/www/cob/ • Atmospheric http://nadp.sws.uiuc.edu/ • NRI http://www.ftw.nrcs.usda.gov/nri_data.html • CENSUS http://www.census.gov/ • Land Area http://landcover.usgs.gov/natllandcover.html http://landcover.usgs.gov/

  9. Data Availibility • Delivery • SSURGO http://www.ftw.nrcs.usda.gov/ssur_data.html • STATSCO http://www.ftw.nrcs.usda.gov/stat_data.html • National Soil Survey http://www.statlab.iastate.edu/soils/nsdaf/ • PRISM http://ocs.oce.orst.edu/prism/prism_new.html • NCDC http://lwf.ncdc.noaa.gov/oa/ncdc.html • Other • GIS DATA http://www.gisdatadepot.com/catalog/US/index.html • NAWQA Ancillary Data http://wwwdcascr.wr.usgs.gov/pnsp/gis/data/natancil/ • NAWQA WATER http://water.usgs.gov/nawqa/ • USGS GIS Data http://gisdata.usgs.net/

  10. Data ConsiderationsNetwork • ERF1 • Scale, density, dated attributes • Availability, working network • NHD • Connectivity issues, no streamflow attributes • Higher resolution, networking tools • NED/EDNA • No streamflow attributes, errors in connection to watersheds • Reach associated with elevation

  11. Data ConsiderationsNutrient Sources • Fertilizer • Sales by state • Disaggregated by county expenditures • Manure • County estimates based on census, animal units • Some counties grouped • Point Source (PCS) • Lat long errors • Nutrient estimates from design flows • Atmospheric • Few collection sites nationally

  12. Data ConsiderationsNutrient Sources Cont. • Land Use/Cover • NLCD • Questionable confidence in AG classifications • Acceptable time period • NRI • Limited spatially • Ag Census • Every 5 years

  13. Data ConsiderationsDelivery • SOILs • STATSCO - Aggregated characteristics, 1:250K • SSURGO - Very limited availability, County • Geology • Limited availability, very general at regional scale • Precipitation and Temperature • Limited sampling locations • PRISM cost $$

  14. Data Types, Processing Methods,and Aggregation Reach 3124 ATD = 2.1 kg/ha-yr • Point • Discrete • Continuous • Within watershed • GRID (Raster) • Average value • Summed value • County Census • Area weight • By land use area • Polygon • Linear (accumulation)

  15. Processing Point Source data • Map of point source data • Overlay watersheds • Sum load by watershed (one time period) • Or average by site, then sum by watershed • Be careful of no data and zero values • AND/OR • Convert point to grid • Zonalmean to link site ID and reach • Watershed as ZONE, Point source ID as value • Average load by site (or not) • Sum by reach watershed

  16. Creating continuous data from points NTN locations from web site Included Site ID and Ion conc. 1982 – 2000 Linear spatial interpolation for wet-deposition for nitrate

  17. Creating continuous data from points

  18. Accumulation using the GIS • Climb and d-climb routines in SPARROW • Allows for the accumulation of reach-associated data • Information at any location on the network • Using linear reach network and GIS • Move up or down network to accumulate • NHD tools (flow tables) • Arcplot • TRACE ACCUMULATE • AML’s

  19. Accumulating area Can accumulate any information associated to the reach. Land use area Fertilizer Could also display as a percent

  20. Kg of N from Manure Recovered from Confined Operations • Aggregation of county statistics • Manure by county • Manure by ag area in county

  21. Kg of N from Manure Recoverable from Confined Operations County Load Watershed Load County AgricultureLoad

  22. Kg of N from Manure Recoverable from Confined Operations County load in AG area Load weighted by county area only Load weighted by AG area in county

  23. TN load from manure in the watershed? • Weight factor = AG area in county in Watershed Segment Divided by TOTAL Ag area in County • Load in watershed = Weight factor * N Load by County • Then N is summed by watershed • Useful if have to weight other county data by ag area

  24. How much Fertilizer is in the watershed? • Load per Agricultural pixel = Fertilizer load in county Divided by Number of Ag Pixels in County • Load in watershed = Sum N Load by Watershed • Can be obtained by using ZONALSUM (Grid) • Watershed GRID is ZONE GRID • Fertilizer load in ag area is VALUE GRID

  25. A value per county

  26. Focus on Ag area

  27. Divide load value by number of AG pixels in county

  28. Sum load by watershed

  29. Kg of N from Manure Recovered from Confined Operations

  30. Data Management Issues • Directory Structure • Units and Unit Conversions!!!! • What do you do with all this data? • One load value per source per reach ID • Both input and output (Predictions) • INFO files and or DBMS • AV projects of Source and Delivery data • Updates and Corrections to data

  31. Directory structure Organize by topic Organize by data set source Decide on UNITS of data Naming conventions Datasets Column names in data base DOCUMENT as you go!!!!!

  32. Preparing data for model • 1 value per reach ID • Extract from DBMS or data set

  33. Managing input and output data • AV 3.X supports multiple documents • AV/AM Project organization by contaminant • AV/AM View and layout organization • Creating Datasets (Coverage, Shapefile, or GRID) of contaminant containing all predicted parameters • Using DBMS and Joining tables • Cloning Views and layouts

  34. Spatial Data Management INPUT source Data

  35. Spatial Data Management Views of Source data in native form Source data aggregated to watersheds Delivery data too

  36. Spatial Data Management Organize AV projects by contaminate Organize Views by Prediction Allows for comparison Incremental vs Delivered Individual sources Individual source and All sources

  37. Spatial Data Management

  38. Spatial Data Management

  39. Joined table with all information allows for display and analysis Can also save as data set (shapefile) maintaining joined table JOINITEM does same thing, so does joining tables in AM

  40. Diagnostics • Mapping Residuals (observed minus predicted) at calibration sites

  41. SUMMARY Section 5 • A network………… • Spatially references source, delivery, and prediction information • Requires connected stream reaches and watersheds with common ID • Requires streamflow and velocity for each reach • Requires associated water-quality and flow stations • Several options have been presented regarding; • Network development and application • Data sets • Data management and aggregation • Circumstances will vary regarding which techniques are better suited for model and network construction and application. • Each method does not necessarily meet each circumstance entirely.

  42. SUMMARY Section 5 • Every data set has limitations • Understand the limitations • Aggregation techniques • One value per reach to input into model • One value per reach for output • Explore data management options • Document as you go • Decide on units and conversions

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