Best Management Practices and the Chesapeake Bay Program Watershed Model

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Best Management Practices and the Chesapeake Bay
Program Watershed Model

• Jeff Sweeney
• University of Maryland
• Chesapeake Bay Program Office
• jsweeney_at_chesapeakebay.net
• 410-267-9844
• Potomac Watershed Forum IV
• George Mason University - Prince William Campus
• August 12, 2005

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Chesapeake Bay ProgramCurrent Modeling Structure
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Purposes of the Chesapeake Bay ProgramWatershed
Model

• Measure the environmental effects of particular
  management schemes for planning purposes.
• Whats the impact of BMP implementation on
  nitrogen, phosphorus, and sediment loads?
• Results help direct tributary strategy
  development
• What yields the biggest bang and the biggest bang
  for the buck?
• Load allocations
• Equitably account for all load sources.
• Measure of loading cap maintenance
• Provide loads to the Estuary Model
• Whats the impact of BMP implementation on living
  resources/water quality?
• What yields the biggest bang and the biggest bang
  for the buck?
• Remove impairments by 2010
• Attainment of water quality standards in the
  Chesapeake Bay will be determined by tidal water
  monitoring data, not the models.

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VA Lower PotomacLoad and BMP Data
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VA Lower PotomacNitrogen Loads to the Chesapeake
Bay
2003 2010 Strategy Load Reductions
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VA Lower PotomacPhosphorus Loads to the
Chesapeake Bay
2003 2010 Strategy Load Reductions
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VA Lower PotomacSediment Loads to the Chesapeake
Bay
2003 2010 Strategy Load Reductions
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Chesapeake Bay WatershedTributary Strategy
Agricultural BMPs
BMPs in red are in VA Lower Potomac Tributary
Strategy
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Chesapeake Bay WatershedTributary Strategy Urban
and Mixed Open BMPs
BMPs in red are in VA Lower Potomac Tributary
Strategy
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Chesapeake Bay WatershedTributary Strategy
Forest, Septic and Shoreline BMPs
BMPs in red are in VA Lower Potomac Tributary
Strategy
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Chesapeake Bay Watershed ModelOpportunities for
BMPs
Input Data
River Simulation
Opportunities for BMPs
Land Simulation
Output
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Chesapeake Bay Watershed ModelOpportunities for
BMPs

• BMPs involving landuse conversions
• BMPs with nutrient and sediment reduction
  efficiencies
• BMPs with both landuse conversions and reduction
  efficiencies
• BMPs that alter nutrient applications to cropland
• Diet and feed changes
• Manure transport
• Nutrient management applications

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BMPs Involving Landuse Conversions
Fertilizer
Atmosphere
Manure
Runoff
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BMPs Involving Landuse Conversions
Fertilizer
Atmosphere
Manure
Runoff
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AgriculturalBMPs Involving Landuse Conversions
Load reductions attributed to movement to
lower-exporting landuses.
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Urban, Mixed Open and Septic BMPs Involving
Landuse and Source Conversions

• Load reductions attributed to
• movement to lower-exporting landuses.
• In the case of septic connections,
• its assumed in the hook-up of
• septic to sewer, load is now part of
• tracked point source discharge.

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Chesapeake Bay Watershed ModelOpportunities for
BMPs

• BMPs involving landuse conversions
• BMPs with nutrient and sediment reduction
  efficiencies
• BMPs with both landuse conversions and reduction
  efficiencies
• BMPs that alter nutrient applications to cropland
• Diet and feed changes
• Manure transport
• Nutrient management applications

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BMPs With Nutrient and Sediment Reduction
Efficiencies
Fertilizer
Atmosphere
Manure
Runoff
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BMPs With Nutrient and Sediment Reduction
Efficiencies
Fertilizer
Atmosphere
Manure
Runoff
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BMPs With Nutrient and Sediment Reduction
Efficiencies

• How Efficiency BMPs Are Credited In The Model
• Reduction acres treated by BMP BMP efficiency
• total segment acres
• By Landuse and Model Segment

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BMPs With Nutrient and Sediment Reduction
Efficiencies

• How Efficiency BMPs Are Credited In The Model
• BMPs That Cannot Be Applied To Same Landuse
• Mutually Exclusive Additive In Nutrient
  Reduction Capabilities
• Examples
• Riparian forest and grass buffers
• Pasture grazing BMPs
• Urban stormwater BMPs
• Several BMPs On Same Landuse Consecutive
• One BMP Reduces The Nutrients Available For
  Subsequent BMPs Multiplicative In Nutrient
  Reduction
• Examples
• Conservation Plans
• Cover Crops

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Agricultural BMPsWith Nutrient and Sediment
Reduction Efficiencies
BMP efficiencies for removing TN, TP, and SED are
collaboration of Bay Program Subcommittee and
Workgroup participants (i.e., peer review) after
appraisal of literature and/or best professional
judgment.
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Urban and Mixed Open BMPsWith Nutrient and
Sediment Reduction Efficiencies
BMP efficiencies for removing TN, TP, and SED are
collaboration of Bay Program Subcommittee and
Workgroup participants (i.e., peer review) after
appraisal of literature and/or best professional
judgment.
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Urban, Septic and Forestry BMPsWith Nutrient and
Sediment Reduction Efficiencies
BMP efficiencies for removing TN, TP, and SED are
collaboration of Bay Program Subcommittee and
Workgroup participants (i.e., peer review) after
appraisal of literature and/or best professional
judgment.
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Chesapeake Bay Watershed ModelOpportunities for
BMPs

• BMPs involving landuse conversions
• BMPs with nutrient and sediment reduction
  efficiencies
• BMPs with both landuse conversions and reduction
  efficiencies
• BMPs that alter nutrient applications to cropland
• Diet and feed changes
• Manure transport
• Nutrient management applications

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Agricultural BMPs With Both Landuse Conversions
and Reduction Efficiencies

• Riparian buffer and wetland efficiencies
• vary by hydro-geomorphic region.
• Wetland restoration is treated the
• same as riparian forest buffers.
• Forest and grass buffers are additive between
  each
• other but multiplicative with other BMPs.

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Urban and Mixed Open BMPs With Both Landuse
Conversions and Reduction Efficiencies

• Riparian buffer and wetland efficiencies for
  mixed open vary by hydro-geomorphic region.
• Wetland restoration is treated the
• same as riparian forest buffers.

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Chesapeake Bay Watershed ModelOpportunities for
BMPs

• BMPs involving landuse conversions
• BMPs with nutrient and sediment reduction
  efficiencies
• BMPs with both landuse conversions and reduction
  efficiencies
• BMPs that alter nutrient applications to cropland
• Diet and feed changes
• Manure transport
• Nutrient management applications

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BMPs that Alter Nutrient Applications to
Cropland
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BMPs that Alter Nutrient Applications to
CroplandNutrient Management Applications

• Phase 4 Watershed Model accounts for both N- and
  P-based nutrient management.
• Phase 4 fertilizer application data is from
  state agricultural agencies.

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BMPs that Alter Nutrient Applications to
Cropland Nutrient Management Applications

• Phase 4 Watershed Model accounts for both N- and
  P-based nutrient management.
• Phase 4 fertilizer application data is from
  state agricultural agencies.

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BMPs that Alter Nutrient Applications to
Cropland Nutrient Management Applications
Fertilizer
Atmosphere
Manure
Runoff
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BMPs that Alter Nutrient Applications to
Cropland Nutrient Management Applications
Fertilizer
Atmosphere
Manure
Runoff
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BMPs that Alter Nutrient Applications to Cropland
Nutrient Management Applications
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Chesapeake Bay Program Phase 5 Watershed Model
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Chesapeake Bay WatershedModeled Landuses
All BMPs applied to Phase 4.3 model landuses
must be accurately distributed to Phase 5
landuses
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Chesapeake Bay Watershed ModelBMP Spatial Scale
Phase 4 County-Segments

• BMP implementation levels are known or have been
  submitted by jurisdictions in the following
  spatial scales
• state
• state-segment
• tributary strategy basin
• TMDL basin
• county
• county-basin
• county-segment
• point (latitude-longitude)

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Chesapeake Bay Watershed ModelBMP Spatial Scale
Phase 5 Land Segments
Phase 5 River Segments
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Chesapeake Bay Watershed ModelExtension for
Phase 5
Phase 5 Watershed Model Extention
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Chesapeake Bay Watershed ModelCalibration
Phase 4.3 Calibration
Phase 5 Calibration
Calibration sites 26 Watersheds 94 Land uses
9 Simulation Years 17
CB Watershed Calibration sites 237 Watersheds
684 Land uses 24 Simulation Years 20
Extended Network Calibration sites
296 Watersheds 899
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Chesapeake Bay Program Models

• Attainment of water quality standards in the
  Chesapeake Bay will be determined by tidal water
  monitoring data, not the models.

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Chesapeake Bay Watershed ModelInformation
Resources

• http//www.chesapeakebay.net/tribtools.htm
• Watershed Model Inputs and Outputs
• Best Management Practices
• Chesapeake Bay Program Technical Reports
• Presentations
• Cap Setting and Allocation
• Chesapeake Bay Models
• http//www.chesapeakebay.net/pubs/1127.pdf
• Chesapeake Bay Watershed Model Land Use and Model
  Linkages to the Airshed and Estuarine Models
• http//www.chesapeakebay.net/pubs/777.pdf
• Chesapeake Bay Watershed Model Applications
  Calculation Of Nutrient Sediment Loadings -
  Appendix H Tracking Best Management Practice
  Nutrient Reductions in the Chesapeake Bay Program
  
• http//www.chesapeakebay.net/committee.htm
• Nutrient Subcommittee
• Agricultural Nutrient Reduction Workgroup
• Forestry Workgroup
• Point Source Workgroup
• Sediment Workgroup
• Tributary Strategy Workgroup
• Urban Stormwater Workgroup