HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Figures Only Full Text Free Full Text (PDF) Free Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via ISI Web of Science (3) Citing Articles via Google Scholar Google Scholar Articles by Benham, B. L. Articles by Wynn, J. W. Search for Related Content PubMed PubMed Citation Articles by Benham, B. L. Articles by Wynn, J. W. Agricola Articles by Benham, B. L. Articles by Wynn, J. W. Related Collections Surface Water Quality Water Quality Watershed and Landscape Processes Other Models Water Pollution

TECHNICAL REPORTS

Surface Water Quality

Development of Bacteria and Benthic Total Maximum Daily Loads

A Case Study, Linville Creek, Virginia

Virginia Tech, Biological Systems Engineering (0303), Blacksburg, VA 24061

^* Corresponding author (benham{at}vt.edu)

Received for publication November 7, 2004. Two total maximum daily load (TMDL) studies were performed for Linville Creek in Rockingham County, Virginia, to address bacterial and benthic impairments. The TMDL program is an integrated watershed management approach required by the Clean Water Act. This paper describes the procedures used by the Center for TMDL and Watershed Studies at Virginia Tech to develop the Linville Creek TMDLs and discusses the key lessons learned from and the ramifications of the procedures used in these and other similar TMDL studies. The bacterial impairment TMDL was developed using the Hydrological Simulation Program—Fortran (HSPF). Fecal coliform loads were estimated through an intensive source characterization process. The benthic impairment TMDL was developed using the Generalized Watershed Loading Function (GWLF) model and the reference watershed approach. The bacterial TMDL allocation scenario requires a 100% reduction in cattle manure direct-deposits to the stream, a 96% reduction in nonpoint-source loadings to the land surface, and a 95% reduction in wildlife direct-deposits to the stream. Sediment was identified as the primary benthic stressor. The TMDL allocation scenario for the benthic impairment requires an overall reduction of 12.3% of the existing sediment loads. Despite the many drawbacks associated with using watershed-scale models like HSPF and GWLF to develop TMDLs, the detailed watershed and pollutant-source characterization required to use these and similar models creates information that stakeholders need to select appropriate corrective measures to address the cause of the water quality impairment when implementing the TMDL.

Abbreviations: GWLF, Generalized Watershed Loading Function • HSPF, Hydrological Simulation Program—Fortran • LA, load allocation • MOS, margin of safety • RBP II, Rapid Bioassessment Protocol II • TMDL, total maximum daily load • VADEQ, Virginia Department of Environmental Quality • WLA, waste load allocation