Located approximately five miles north of Capitol Hill, the east-west oriented Kennedy Street became the site for a national design competition launched in April 2013 by DC Water. Nitsch Engineering served as the project manager for the winning Kennedy|Greened competition entry, collaborating with a multi-disciplinary team to design a high-performance, urban residential streetscape retrofit that serves as a model for green infrastructure to help address the District’s combined sewer overflow.

Phase I of the competition challenged teams to develop innovative concepts for public or private spaces throughout the District. The Nitsch Team submitted an award-winning design for a residential section of Kennedy Street NW (between 13th Street NW and Georgia Avenue NW), integrating porous pavements, bioretention bump-outs and planters, subsurface storage, pedestrian boardwalks, and an engaging proposal for environmental art. The Nitsch Team was invited as one of two teams to enter the Phase II competition, which required preparing a 15% streetscape design for a more commercial section of Kennedy Street NW (between 1st Street NW & 2nd Street NW). We emerged from Phase II as the winning streetscape design, and are now working with DC Water to complete the design and construction of the green infrastructure solutions.

This pilot project is significant for the District as well as DC Water. DC Water has entered into a Long Term Control Plan with the District of Columbia, the United States Department of Justice, and United States Environmental Protection Agency to reduce Combined Sewer Overflow (CSO) discharges to the Anacostia and Potomac Rivers as well as Rock Creek. In addition to constructing two massive underground tunnels capable of collecting and storing CSO water, preventing it from being discharged to surrounding waters, a significant component of DC Water’s strategy is to implement green infrastructure strategies in the Rock Creek watershed that will collect stormwater and infiltrate it into the ground, preventing it from being discharged to the combined sewer system.

The Nitsch Team’s design will provide environmental, social, and economic benefits to Kennedy Street by incorporating increased landscaping into the streetscape that will collect and infiltrate stormwater. The project includes the design and construction of 33 green infrastructure Best Management Practices (BMPs) including bioretention curb extensions, landscape infiltration gaps, permeable pavers, and dry wells. Runoff flows from one BMP to the next, offering multiple opportunities for retaining and detaining stormwater, instead of allowing it to rapidly discharge to the combined sewer.

Due to the innovative nature of the project, as well as its location within a public right-of-way, the Nitsch Team has guided the project through the complex permitting required by the District Department of Transportation (DDOT), the District Department of the Environment (DDOE), and various other permitting authorities. We also led a thorough public education and outreach effort, developing graphics and educational tools for use at two facilitated public meetings.

As sustainable stormwater experts, Nitsch Engineering employs a collaborative approach among a team of landscape architects, community engagement specialists, an environmental artist, and other consultants offering local support.

Sustainable Project