The Hare Snipe Creek watershed is a 7.2 square mile watershed located in northwestern Raleigh, North Carolina. The watershed is nearly fully developed and undergoing redevelopment, and experiences regular flooding events that negatively impact residents. Brown and Caldwell developed an integrated watershed study for the City of Raleigh to help identify and evaluate potential flood mitigation and water quality improvements. The study included developing an equity framework, supporting public outreach, conducting stream assessments, monitoring stream flow, processing gauge adjusted rainfall data, water quantity modeling, water quality modeling, and project identification. This study served as a pilot for future studies throughout the City’s watersheds.
Approximately 50 projects were identified based on public flooding complaints, existing nutrient loads, and the existing condition model results. These projects were categorized as Stormwater Control Measures, Green Stormwater Infrastructure, Stream Restoration, Infrastructure Improvements, and Operable Control Structures. The projects were incorporated into the hydrologic and hydraulic model to evaluate their effectiveness to mitigate flooding without negatively impacting downstream roadways and structures. Additionally, cost estimates and fact sheets were provided for each project. The City used this information to assess each project for implementation in their Capital Improvement Plan.
Modeling results for the existing conditions model, future conditions model, and scenario analysis were presented in a final report as well as online maps. Additionally, the existing conditions model is intended to be continually refined with more detail as needs and opportunities are identified. This presentation includes discussion of the hydrologic and hydraulic methods utilized in the modeling of the watershed, the results and effectiveness of the scenario analysis, and the limitations of the models and results.