Projects

Stream and Stormwater Design Emergency Sewer Repairs  

As part of the DC Water Sewer Program Annual Work Plan, DC Water evaluated the existing conditions of the District of Columbia’s water and sewer assets. When critical issues such as broken or exposed pies adjacent to waterways were discovered through inspections, complaints, or other means, DC Water identified these areas for emergency repairs to be addressed under its various design contracts. 

As part of a team holding one of these contracts, Coastal Resources, Inc. (CRI) provided on-call stream restoration and stormwater management design services for emergency sewer repair or restoration in or near streams. CRI performed site evaluations and geomorphic assessments of the streams to be restored at the location of exposed or damaged sewer assets. Concept level designs were generated that included details, plan view, profile, and cost estimates. The concept designs were created in AutoCAD, Microstation, or ArcGIS depending on the available information/background data. The designs were presented to DC Water and other property owners/stakeholders for review and concurrence. CRI performed the site evaluation and concept design work at the following sites: 

Oxon Run: The stream restoration at Oxon Run was part of a larger effort to assess the Oxon Run Interceptor from Southern Avenue SE to the Blue Plains Advanced Wastewater Treatment Plant. The Oxon Run sewer line was threatened in several locations due to widespread instability of the stream and its embankments. CRI evaluated 10 pre-selected locations requiring asset protection and stream restoration. At these locations, CRI performed field investigations and collected and analyzed geomorphic data to identify the preferred stream restoration methods required to protect these sewers, as well as the relocation of at least one sewer so a more natural/sustainable stream channel could be implemented. Concept restoration designs were then developed including preliminary design details and cost estimates. The concepts and estimates will aid DC Water with prioritization and facilitate future detailed design tasks.

14th and Gallentine St, NE: The unnamed tributary to Northwest Branch of the Anacostia flows northeast from a box culvert near the intersection of 14th St NE and Gallatin Street NE. A sewer pipe owned and maintained by DC Water was exposed in the unnamed tributary. CRI performed a detailed stream assessment and evaluated three design strategies to achieve the goals of protecting DC Water’s assets and providing a long-term solution to the observed stream instability. CRI provided DC Water with a technical memorandum summarizing the data collected and 3 design alternatives. CRI presented the designs to DC Water and the National Park Service (NPS), the property owner, for input and comment.   

16th and Whittier: CRI performed a site visit and initial hydrologic calculations to produce a conceptual design and cost estimate for the streambank stabilization on a section of an unnamed tributary to Rock Creek near 16th and Whittier Place NE. This work was completed as part of the emergency protection of a 12-inch sewer line. CRI presented the concept design to DC Water and NPS for review and comment. 

18th and Randolph St NW: As part of the repair of a sewer pipe located at an eroded slope along an unnamed tributary to Rock Creek near 18th and Randolph Street NW, CRI developed a permanent streambank stabilization design. CRI performed a site visit, initial hydrology calculations, and prepared a concept design to repair the steep eroded streambank and establish vegetation to prevent future erosion. CRI presented the concept design to DC Water for evaluation and comment.

18th and Ingleside Ave NE: CRI designed a stream restoration and stormwater management facility to address erosion issues at an exposed DC Water asset near 18th and Ingleside Avenue NE. CRI performed a site visit, initial hydrology, and stormwater management calculations to develop a concept design for the restoration of approximately 150 linear feet of stream and installing a stormwater management facility to treat stormwater flowing from the upstream roadway. CRI presented two alternatives to DC Water for evaluation and comment.

Location:

Washington, DC

Client:

DC Water Sewer Program Management

Key Services:

  • Stream & Stormwater Site Evaluation
  • Geomorphic Assessment
  • Stream Restoration Design