Chesapeake 2000 Agreement Water Quality Commitments

1
Chesapeake 2000 AgreementWater Quality
Commitments
1. By 2001, define the water quality conditions
necessary to protect aquatic living resources and
then assign load reductions for nitrogen and
phosphorus to each major tributary 2. Using a
process parallel to that established for
nutrients, determine the sediment load reductions
necessary to achieve the water quality conditions
that protect aquatic living resources, and assign
load reductions for sediment to each major
tributary by 2001.
2
Questions Driving Our Decisions During 2001

• What water quality improvements are needed in the
  Bay and tidal rivers to attain the Bay
  criteria?
• What loadings from where are influencing
  local/regional water quality conditions?
• What reductions from where are needed to ensure
  local/regional attainment of Bay criteria?

3
Follow Three Tracks
1. Diagnose Impairments/ Assess
Environmental Progress
3. Establish Watershed Load Contributions/Estimat
e Magnitude of Reductions Needed
2. Measure Load Reduction Progress/Estimate
Further Reduction Capacity
Tributary/mainstem region statements outlining
where we can get the reductions needed to attain
Bay criteria
Bay Model Scenarios Confirm Allocated Load
Caps Will Attain New Bay Criteria
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1. Diagnose Impairments/ Assess Environmental
Progress
Assess current attainment of criteria across all
tidal waters
Assess restoration of Bay biological
communities as quality fish food
Diagnose reasons for lack of criteria
attainment/ lack of biological restoration
Assess rate of progress towards achieving
needed improvements
Estimate improvements needed in ambient
concentrations
Tributary/mainstem region statements outlining
where we can get reductions needed to attain Bay
criteria
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2. Measure Load Reduction Progress/ Estimate
Further Reduction Capacity
Map out implementation trends relative to Trib
Strat. commitments
Run actual hydrology WSM 1985-2000 progress
scenarios
Develop population/load trends projections
Develop multi-scale nutrient/ sediment loading
profiles
Estimate further program implementation/load
reduction capacity
Tributary/mainstem region statements outlining
where we can get the reductions needed to attain
Bay criteria
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3. Establish Watershed Load Contributions/ Estima
te Magnitude of Reductions Needed
Run tracer scenarios for first cut at whose load
influences whose water quality
Estimate relative contributions from small
watersheds to total loads delivered to tidal
waters
Visualize relative load contribution from
all small watersheds to each tidal CBP segment
Document up-watershed load reduction to
downstream tidal WQ response connections
Estimate magnitude of further nutrient/ sediment
reductions needed to attain Bay criteria
Tributary/mainstem region statements outlining
where we can get the reductions needed to attain
Bay criteria
7
Bay Model Scenarios Confirm Allocated Load Caps
Will Attain New Bay Criteria
2
Tributary/mainstem region statements outlining
where we can get reductions needed to attain Bay
criteria
1
3
Run set of sequenced model scenarios with
increasing geographic specificity, then building
back up to basinwide
Confirm proposed allocated load caps will attain
Bay criteria across all tidal waters
NEW LOAD CAPS ALLOCATED TO TRIBUTARY BASINS
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2001 Schedule

• January-March
• Derive draft Bay criteria, tidal designated uses
• Assess current status of Bay criteria attainment
• Diagnose causes of non-attainment
• Map out progress to date, projections through
  2010
• Estimate relative load contributions to tidal
  segments
• First Quarter Products
• Tributary basin profiles expanded to include
  status/trends in criteria attainment, 1985-2000
  implementation/load trends, relative load
  contributions

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2001 Schedule

• April-June
• Program/stakeholder review of Bay criteria
• Estimate WQ improvements needed to attain
  criteria
• Develop multi-scale source/loading profiles
• Estimate further load reduction capacity
• Estimate magnitude of load reductions needed
• Second Quarter Products
• Tributary basin profiles expanded to include
  where we can get nutrient/sediment reductions
  needed to attain Bay criteria, preliminary range
  of reductions required

10
2001 Schedule

• July-September
• Bay criteria revised to reflect review comments
• Run series of geographic specific Bay WQ model
  scenarios driven by monitoring/implementation
  capacity analysis findings
• Third Quarter Products
• Tributary basin profiles expanded to include
  continually updated findings regarding model
  scenarios relative to each tributary basin range
  of loading caps allocated by basin

11
2001 Schedule

• October-December
• EPA review/publication of Bay criteria
• Bay WQ scenarios building up to more regional,
  then baywide scales to address inter-basin
  influences
• Model scenarios confirming final proposed cap
  load allocations will attain Bay criteria
• Fourth Quarter Products
• EPA published Bay criteria document
• Final loading caps allocated by tributary basin