1 / 11

Develop/update spreadsheet model for regional loading and trends

Develop or update a spreadsheet model to estimate contaminant loads and trends in the San Francisco Estuary based on land use, rainfall, and runoff data.

cshier
Download Presentation

Develop/update spreadsheet model for regional loading and trends

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. San Francisco Estuary Institute Item #3a Develop/update spreadsheet model for regional loading and trends Michelle Lent, John Oram, and Lester McKee Sources Pathways and Loadings Workgroup May 6th 2010

  2. San Francisco Estuary Institute Item #3a Background: Version 1 • Developed by Davis et al. in 2000 to estimate contaminant loads to Bay and coastal waters • Simple rainfall/runoff model • Loads generation: W =  Cj rj i  Aj j where j = land use categories • Loads estimated for: • TSS • Cadmium • Chromium • Copper • Lead • Nickel • Zinc • BOD

  3. San Francisco Estuary Institute Item #3a Background: Version 1 • Spatial extent • CalWater HUC8 • Spatial resolution • 34 watersheds • Temporal resolution • Long-term average annual scale

  4. San Francisco Estuary Institute Item #3a Updates/Refinements • Replace 1995 ABAG Land Use data set with ABAG 2005 (unless WG recommends differently) • Increase spatial resolution (finer-scale watersheds) using WLA boundaries and BASMAA nomenclature • Increase land use category resolution (e.g. split out transportation land use – pending outcomes of STLS task 4d) • Use spatially averaged rainfall instead of watershed centroid method • Increase temporal resolution to long-term monthly scale • Calibrate runoff coefficients

  5. San Francisco Estuary Institute Item #3a Spatial Extent Vs. Vs. Or some other extent…

  6. San Francisco Estuary Institute Item #3a Increase temporal resolution • 30-year average monthly PRISM data • 800-meter grid • 100ths of mm rainfall • Potentially could scale/calibrate runoff coefficients by month to account for antecedent conditions, e.g. using Z4LA data

  7. San Francisco Estuary Institute Item #3a Impacts of increasing spatial and temporal resolution: ~3*10 Watersheds ~5*102 Watersheds Vs. If 10 POC loads calculated per watershed, Annual output: ~3*102 Monthly output: ~3*103 If 10 POC loads calculated per watershed, Annual output: ~5*103 Monthly output:~5*104 …so will need to aggregate watershed output for reporting

  8. San Francisco Estuary Institute Item #3a Landuse-based Runoff Coefficients…some options: • Previous version of model (BASMAA, 1996; SCCWRP, 2000) - Developed specifically for Bay Area (mostly) • Rantz, 1971 - Developed specifically for Bay Area • Browne, 1996 - Also split out by slope and soil group • Compilation in Park et al., 2009

  9. San Francisco Estuary Institute Item #3a Potential pollutants to model (as land-use-specific data are available) • MRP Category 1: • Suspended Sediments • Total Organic Carbon • Copper • Mercury • PCBs • Nitrate as N? • MRP Category 2: • Selenium • Phosphorous • PBDEs • PAHs • Pyrethroids • OC Pesticides • Chlordane • DDTs • Dieldrin Need to prioritize effort: Base model development versus Number of pollutants added

  10. San Francisco Estuary Institute Item #3a Reached consensus? • Spatial extent of model • Desired aggregation of output • Recommended runoff coefficients to try • How to divide time/effort between base model development (e.g. calibration) and further model development (e.g. adding in more POCs) • Which POCs to include in this phase and which to include in subsequent phases • Any other issues?

  11. San Francisco Estuary Institute Item #3a RMP 2011 rationale for further support • This model supports STLS/MRP management questions by: • Providing regional loads estimates • Testing BMP options • In 2010 the model will: • Provide average monthly regional estimates of storm water volume, suspended sediment loads, and other POC loads (as specified by WG) • In 2011, with further funding, the model could potentially: • Provide average monthly regional loads estimates of more POCs • Be further calibrated to runoff, if needed/desired • Be updated with local land-use specific EMCs, if available • Have BMP testing capabilities developed

More Related