men lining underground pipe in street

Martha Washington/Washington Highlands Sewer Improvement Project

Project Overview

The project will address the need for increased capacity and the reduction of sewer overflows. The improvements will extend the life of the current MIS by 50 years. Approximately 12,000 feet of MIS will be rehabilitated by lining segments to create a pipe within a pipe. This process is called cured-in-place-pipelining or CIPPL. This trenchless approach is cost-effective and reduces impacts on the businesses and residents during construction.

Work will progress segment by segment (manhole to manhole). There will be traffic impacts along the work areas. During construction, travel lanes will be reduced.  Parking lanes and bike lanes will be closed in some areas. Traffic maps and travel impacts will be posted to this webpage before construction begins. They will be found in the project documents/resources section below.

The capacity improvement portion of the work will take place along Garfield Avenue between 67th St and 66th Street. The carrying capacity of the MIS sewer will be increased by increasing the size of the local sanitary sewer in this area, decreasing demand on the MIS.  This sewer installation will involve digging the trench for the new pipe, connecting the sewer laterals, burying the new pipe, and restoring the roadway.  Garfield Avenue will be closed to through traffic during the sewer construction and restoration work.  Access to driveways will be provided.

Project Map

Project Benefits

  • Rehab and Line 25,000 ft of MIS extending the life of the sewer
  • Reduce Inflow and Infiltration
    • Inflow and infiltration can cause problems in sewer systems. Inflow is the flow of stormwater or surface water into the sewer system through incorrect connections, which can lead to capacity issues. Infiltration occurs when groundwater seeps into the sewer system through cracked or defective pipes.
  • Reduce sewer overflows by either:
    • Increase the MIS pipe along Garfield Ave. between 66th and 67th Streets
    • Or upsize the local sewer, increasing capacity

Timeline*

  • Outreach – Spring 2026
  • Construction – September 2026 – March 2028
  • Post-construction – April 2028 -April 2030
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    Example of equipment and vehicles you may see during construction. 

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    The old sewer pipes will be lined to extend their life. 

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    The contractor is using a cure-in-place method to rehabilitate sections of the sewer.

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    The cure-in-place method is less disruptive than the open-trench method and more cost-effective. 

Partners

Get Involved/Stay Informed

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Comments/Questions

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