Our Approach
Anne Arundel County enlisted Straughan to assist with a study that identified causes of regional flooding issues among residential subdivisions along Clark Station Road in Severn, MD and evaluate the feasibility of an array of solutions to the flooding issues. The study included desktop analysis and field investigations of existing infrastructure and drainage issues, as well as modeling of the existing storm drainage system. We developed a comprehensive hydrology and hydraulics model using Autodesk Storm and Sanitary Analysis software to simulate existing regional flooding issues and identify deficiencies in the existing drainage system.
With the help of the comprehensive model, Straughan evaluated several alternative improvements including upgrading the storm drainage systems to County standards, partially upgrading the storm drainage systems and adding stormwater management best management practices, as well as a no-build option with restrictions on development. We evaluated the relative improvement provided by each alternative, the feasibility, and the cost-effectiveness for Anne Arundel County.
For the downstream impact study, Straughan performed an additional evaluation of downstream flood impacts that included floodplain data reviews, additional field measurements, USGS StreamStats flow computations for five (5) design scenarios, HEC-RAS hydraulic modeling for about 3,300 feet of downstream stream channels with two culvert structures, floodplain mapping and profiles, technical memo, and evaluation of outfall for potential MS4/TMDL credit.
