Responding to the first Impervious Cover-based TMD l in the nation

In 2007, the Connecticut Department of Environmental Protection promulgated the first total maximum daily load (TMDL) in the country based on impervious cover. This TMDL, developed as a way to deal with streams impaired by poorly understood urbanization-related impacts, is for Eagleville Brook, a small watershed that drains much of the University of Connecticut campus. What is an impervious cover TMDL? This article reviews the status and findings of an ongoing project designed to devise an effective and pragmatic response to this new approach. Using the language in the TMDL itself as a starting point, the project team focused on impervious cover disconnection and the related goal of reducing stormwater runoff volume. However, the “bottom line” of improving biota-based indicators of stream health will also require approaches beyond what would result from a strict focus on impervious cover. Based on geospatial data analysis followed by extensive field work, the project team has identified 51 retrofit opportunities, including a “Top Ten” list that attempts to maximize both the environmental and social or educational impacts of the response. Although the watershed plan has not yet been written, considerable progress has been made on campus, including the replacement of conventional parking lots with pervious materials and changes to plans for upcoming construction. The team’s preliminary conclusion is that combining the simple framework of impervious cover with the force and accounting rigor of a TMDL can be an effective way to catalyze communities to plan and implement actions to remediate stormwater problems.