Project
The Challenge
Delaware’s three inland bays are a major economic and natural resource for Sussex County and the State of Delaware. Dewey Beach, located within the Delaware Inland Bays Watershed, is a small coastal community that is home to fewer than 400 year-round residents, and is a beach and bay destination for more than 1.2 million annual visitors. Since its incorporation in 1981, Dewey Beach has experienced intense development to accommodate the seasonal influx of visitors.
Development has brought an increase in impervious cover, which has soared to 58% within town boundaries; 10% is the widely cited watershed threshold for impervious cover where a decrease in receiving water quality begins. The large area of impervious cover generates a significant amount of runoff during storm events that directly enters Rehoboth Bay via streets (overland flow) and through storm drains. In addition to causing localized flooding, the untreated stormwater delivers a significant amount of nutrients and sediments to the bay (nonpoint source pollution).
Because of this, Dewey Beach secured a Surface Water Matching Planning grant to develop Phase II of their Stormwater Master Plan for Nutrient Reductions in FY2017. Preliminary findings of this plan characterized flooding not only as a result of significant runoff generation from the impervious cover, but also from undersized and/or non-functioning infrastructure and tidal surcharge from the bay through the storm drains during high tide and wind events.
Client
Services Provided
The Solution
Working with the Delaware Center for the Inland Bays, RK&K implemented a living shoreline (an alternative stabilization technique that uses naturally occurring materials to maintain or enhance environmental benefits of bay shorelines) as well as upgrade a stormwater drain and outfall designed to reduce flooding during storms.
RK&K performed a shoreline assessment, including design wave, hydrologic/hydraulic design of the storm drain outfall, prepared conceptual and final design plans, and provided permit support. This task was completed by means of a designer-led design-build delivery mechanism. For this task order, RK&K served as lead designer, and retained the services of and entered into a design-build subcontract agreement with a qualified contractor.
