Water Quality Trading in Practice: A Comparative Analysis of Adoption Practices between Water Quality Credits and more Traditional Water Quality Compliance Options in Roanoke, Virginia
Abstract
Water quality trading (WQT) is a market-based approach used to reduce the cost associated with meeting water quality regulations. Due to a lack of available data, study of these programs has been limited to comparing trading structures, evaluating trading ratios, and quantifying the number of trades occurring. The impact of such programs on traditional compliance measures, including the use of onsite best management practices (BMPs), has not been studied. However, knowing how WQT is impacting the use of onsite BMPs to mitigate runoff impacts is important for understanding potential long-term consequences of WQT programs. Using Python to automate data extraction and analysis of an online construction permitting system for Roanoke, Virginia, we collated a novel WQT dataset corresponding with 132 development projects. Using this dataset, we evaluated the adoption patterns of water quality credits, including the types and quantities of development projects for which credits are used, the number of engineering firms using credits, and the temporal adoption rate of credits. We then compared these credit adoption trends with the adoption of BMPs and other traditional compliance measures. We found that 52% of development projects have either used or proposed the use of water quality credits to fully comply with water quality regulations since December 2015. The majority of engineering firms (54%) were found to have used credits to meet water quality requirements. We also identified 14 different project types for which credits were used in Roanoke, including commercial and residential projects. Our findings identify water quality credits to be the preferred compliance option in Roanoke, indicating that offsite treatment is being used the majority of the time to accommodate onsite nutrient discharge into local waterways. Additionally, concerning trends related to credit generation projects being many miles downstream of the urban development location point to potential long-term concerns for water quality. We discuss the potential long-term impacts of this trend on local water quality and offer a brief discussion of potential solutions for addressing such impacts.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2022
- Bibcode:
- 2022AGUFM.H36G..06N