Abstract: Session D 9:30 am (Back to Session D)
Prioritization of Stream Restoration Reaches as Part of a Watershed Assessment
Authors: Brett Schrey, PE, CFM; Roger Windschitl
Harford County, Maryland requested assistance from Stantec Consulting Services, Inc (Stantec) to assist with a watershed assessment for the Upper Bynum Run Watershed. The assessment, which was conducted from August 2017 through June 2018 included baseline stream surveys along Bynum Run and its tributaries, stormwater management facility assessments, and a documentation of upland conditions. The purpose of the assessment was to determine baseline conditions for this medium to high density residential and commercial watershed to meet current National Pollutant Discharge Elimination System (NPDES) Municipal Separate Storm Sewer System (MS4) and Total Maximum Daily Load (TMDL) requirements.
The watershed assessment resulted in the identification of restoration opportunities that could be implemented to improve water quality from nonpoint source runoff and provide ecological uplift and habitat enhancement along stream corridors throughout the watershed. Restoration opportunities identified fifteen (15) reaches for Stream Restoration. Prioritization of the proposed restoration reaches will insure the local municipalities get the most “bang for the buck” in terms of water quality for the treatment of runoff from impervious areas. Concept level designs were completed on these restoration opportunities to evaluate feasibility, cost and nutrient reduction benefits. Detailed field observations determining Near Bank Stress and Bank Erosion Hazard Index helped estimate existing erosion and potential treatment credit. Several human elements were also involved in the prioritization process. These elements include project timing with other capital improvement projects, yearly budgets, and public buy in, etc. All these factors were combined to create a final prioritization ranking and timeline for the proposed stream restoration projects.
The use of online GIS tools specifically Story Maps have been used throughout the project to show the process and results of the watershed assessment to the client and watershed stakeholders. This online presentation will assist private sector, local, and state governments to have a better understanding of what information to gather during a watershed assessment to prioritize potential restoration opportunities, as well as how to present the findings using innovative GIS resources.