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Phase 5.3.2 watershed model

Gary Shenk

PSC

2/17/11

DraftPossible changes dependent on 2/14 WQGIT

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Phase 5.3.2 Watershed Model• In response to issues raised and agreed

upon by the partnership, two changes are being made to the watershed model to produce phase 5.3.2.

• 2010 TMDL based on phase 5.3.0

• 2011 phase 2 WIPs based on phase 5.3.2

• Discussed in Shawn Garvin letter of 6/11/2010 and email of 1/17/2011

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Two Changes Agreed to by AgWG / WQGIT / PSC

• Improved land use estimates with more complete urban coverage– Especially improved in low density areas

• Refinements to the simulation of agricultural nutrient management– Improved definition of nutrient management– Improved data– Improved accounting– Additional details from AgWG/WTWG 1/14/11

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Pilot of 5.3.2 Land Use: Shenandoah Valley

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Improved Land Use Estimates

• Increase in urban land in the Phase 5.3.2 land use data matches better with– Turf grass industry data– Local impervious surface data– State septic data– USDA Agricultural Census

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Refinements to nutrient management

• Improved definition of nutrient management

• Improved application timing data

• Improved manure accounting– Discontinue automatic transfer of manure –

Use the state-reported transfers instead– Improved accounting of all manure nutrients

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Partnership Review

• Improved land use estimates with more complete urban coverage– Independently reviewed by USGS and CBP

STAC– Reviewed by USWG and WQGIT

• Refinements to the simulation of agricultural nutrient management– Refinements arose from WQGIT, WTWG, and

AgWG– Details approved by same groups in Jan 2011

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State data deadline

• Requested data by 2/7/11– Will not be updated in p5.3.2 if not received

by 2/22/11

• Agricultural– Application and CAFO/AFO data

• Stormwater– Do BMPs include federal land?

• Wastewater– Update facility lists

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Outcome of changes dependent on evaluation through a system of

analysis tools