摘要: |
Recent modifications to the way the Virginia Department of Environmental Quality calculates total maximum daily load (TMDL) credits associated with roadway drainage maintenance operations has caused VDOT to re-evaluate how catch basin cleanout operations are tracked and reported. "Catch basin cleanouts" refer to the removal of solids from the road drainage system. This achieves water quality improvements by removing pollutant-laden material which has been washed off the roadway from the stormwater system. In order to receive TMDL credits for these activities, accurate records of the amount and characteristics of the removed material must be recorded. Historically, these cleanouts have not been conducted with a focus on determining TMDL credit allocation. Also, because of the large size of VDOT's storm drain system, these cleanouts are conducted by both state forces as well as contractors. These factors have led to reporting and record keeping inconsistencies which make it difficult to determine the TMDL credits associated with these operations. The purpose of this research effort will be to evaluate current practices used by state and contract forces to conduct catch basin cleanout operations, specifically identifying what information is collected, how the captured material is handled / disposed of, and how contracts to perform this work are structured. This research will result in a final report outlining current catch basin cleanout tracking practices as well as recommendations for how these practices can be modified to better capture the necessary information for calculating TMDL credits. |