Total Maximum Daily Load (TMDL) implementation generates benefits and costs from water quality improvements, which are rarely quantified. This analysis examines a TMDL written to address bacteria and aquatic-life-use impairments on Abrams and Opequon Creeks in Virginia. Benefits were estimated using a contingent valuation survey of local residents. Costs were based on the number and type of bes...

BACKGROUND Many of the practices currently underway to reduce nitrogen, phosphorus, and sediment loads entering the Chesapeake Bay have also been observed to support reduction of disease-causing pathogen loadings. We quantify how implementation of these practices, proposed to meet the nutrient and sediment caps prescribed by the Total Maximum Daily Load (TMDL), could reduce pathogen loadings an...

We appreciate the work of your staff and the New England Interstate Water Pollution Control Commission (NEIWPCC) in preparing a comprehensive and informative TMDL report and incorporating public comment. We also appreciate that Vermont and the other northeast states have been in the forefront of state efforts to develop mercury reduction programs. My staff and I look forward to continued cooper...

We appreciate the work of your staff and the New England Interstate Water Pollution Control Commission (NEIWPCC) in preparing a comprehensive and informative TMDL report and incorporating public comment. We also appreciate that Rhode Island and the other northeast states have been in the forefront of state efforts to develop mercury reduction programs. My staff and I look forward to continued c...

Lake Fuxian is the largest deep freshwater lake in China. Although its average water quality meets Class I of the China National Water Quality Standard (CNWQS), i.e., GB3838-2002, monitoring data indicate that the water quality approaches the Class II threshold in some areas. Thus it is urgent to reduce the watershed load through the total maximum daily load (TMDL) program. A three-dimensional ...

This paper describes a decision analysis approach to TMDL implementation decisions for mercury using a hypothetical mine-impacted tributary in the San Francisco Bay as an example. Decision analysis is a theoretically sound approach for making significant decisions under uncertainty (see, e.g., Howard, 1968; 1988; Keeney and Raiffa, 1976; Clemen, 1996; Merkhofer, 1999). The Bayesian probabilisti...

Prioritizing total maximum daily load (TMDL) development starts by considering the scope and severity of water pollution and risks to public health and aquatic life. Methodology using quantitative assessments of in-stream water quality is appropriate and effective for point source (PS) dominated discharge, but less so in watersheds with mostly nonpoint source (NPS) related impairments. For NPSs...

Section 303(d) of the Clean Water Act requires all states to identify waters that do not meet, or are not expected to meet, applicable water quality standards. For each listed water body that does not meet a standard, states must develop a total maximum daily load (TMDL) for each pollutant that has been identified as contributing to the impairment of water quality in that water body. The Texas ...

To address the impaired condition of the water bodies listed under Section 303(d) of the Clean Water Act, over 40 000 total maximum daily loads (TMDLs) for pollutants must be developed during the next 10-15 years. Most of these will be based on the results of water quality simulation models. However, the failure of most models to incorporate residual variability and parameter uncertainty in the...