cost/benefit study of the impacts of potential nutrient controls for ...

Manageable Unit Analysis Based on Expected
Water Quality Improvement
• Streams & Rivers
– Calculated instream median TP and TIN based on existing data
– POTW discharges based on a 75% design capacity flow
– Assumed effluent concentrations of 4.5 mg/L for TP and 25
mg/L for TIN unless POTW-specific data available
– Background nutrient concentrations (other than POTWs) based
on land use type and associated event mean concentrations
• Lakes & Reservoirs
– Similar assumptions as provided above
– Water quality modeled using Continuously Stirred Tank
Reactor calculation, except where existing model available
– Incorporated reservoir-specific characteristics, as appropriate
Colorado Nutrient Cost/Benefit Study
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