DC Water at Work: Optimal Risk Management of Construction Close to Buried Linear Assets

With a net population increase of 100,000 plus over the last decade in Washington, DC, there has been major infrastructure developments and booming real estate construction, e.g., streetcars, two stadiums, three bridges over the Anacostia in addition to many residential buildings. Often these projects have foundations close to our buried infrastructure. The need for underground parking coupled with restricted building heights has resulted in foundations that are often deeper than and/or are very close to the buried water and sewer infrastructure. In certain instances, the foundations are proposed over or encompassing our sewer infrastructure. In the nation’s capital, modern urbanization started with the oldest trunk sewers and interceptors built from the 1860s through the 1930s with masonry made from a combination of brick, stone, and later non-reinforced plain concrete. These empirically designed and constructed infrastructure predate many modern engineering theories, i.e., soil mechanics post 1930s. DC Water engineers remain at the forefront of protecting these mission critical linear assets of indefinite life duty, by actively managing the forthcoming impacts via collaborating with stakeholders, and by: enforcing the best managed geo-structural practices in design and construction; protecting both the buried linear infrastructure and forthcoming new construction throughout the life cycle of both; and by facilitating future maintenance and expansion. This presentation will showcase a few highlighted projects in the past decade which have led DC Water to develop enhanced utility protection requirements for adjacent construction; and demonstrate that DC Water’s implemented best management practices have a win-win-win outcome for the environment, the developer, and the rate-payer.