Sanitary Water
About Us Jobs News & Publications Environment & Education Business with DCWASA Customer Care Home
About DCWASA > FY 2007 - 2016 Capital Improvement Program >
Sanitary Sewer Service Area
Capital Improvement Program

WASA is responsible for wastewater collection and transmission in the District of Columbia, including operation and maintenance of the sanitary sewer system. WASA's sanitary sewer system includes approximately 600 miles of large interceptor sewers and smaller gravity collection sewers. WASA is also responsible for sewer lateral connections from mains to the property lines of residential, government, and commercial properties. In addition, WASA is responsible for the 50 mile long Potomac Interceptor System, which provides conveyance of wastewater from areas in Virginia and Maryland to Blue Plains. The existing sanitary sewer system dates back to 1810, and includes a variety of materials such as brick and concrete, vitrified clay and concrete, reinforced concrete, ductile iron, plastic, steel, brick, cast iron, cast in place concrete, and even fiberglass.

During FY2004, WASA will continue the evaluation of the sewer system to determine its condition, verify adequate capacity, and to develop new capital projects, as appropriate. A five- year contract was signed in early 2003 with a new engineering project management consultant (EPMC) to provide services for the comprehensive assessment, and this work continues in FY 2004. Funding is included in this 10- year CIP for the new capital projects that may come out of the assessment.

In general, projects in the existing sanitary sewer service area program provide for replacement or rehabilitation of the system as well as extensions to this system for development and growth as needed. As in last year's program, the current 10- year plan reflects the substantial costs of street repaving due to the new street repair and restoration regulations required of WASA and other area utilities by the District.

The current CIP includes the following projects:

Sanitary Sewer Service Area Management — $14.9 million

During FY2004, WASA will continue the comprehensive evaluation of the sanitary and combined sewer systems, as well as design management for sewer pumping station rehabilitations, as described in more detail below.

  • Sanitary Sewer Program Management & Planning (EPMC- IIIA) - This planning allows WASA to assess the sewer system to determine if it is in adequate structural condition, and has sufficient capacity to meet current service demands and planned growth. The planning effort required to comply with the current National Pollutant Discharge Elimination System (NPDES) permit, the three- party consent decree, and pending federal regulations addressing sanitary sewer overflows is also included in this initiative.
  • Design Management for Sanitary Sewer Pumping Stations - This ongoing project began in 2001, and provides for the management of the design of three small sanitary sewage pumping stations requiring major rehabilitation or replacement. A project design engineer has been selected and the design will be finalized in FY2004.

TOPtop

Collection Sewer Projects — $15.2 million

This program includes studies and projects to effectively eliminate stormwater, groundwater, and other infiltration and inflow to the sewer system, to separate stormwater flows, and to reduce other extraneous flows to Blue Plains. This category also includes projects to rehabilitate collection system sewers as well as projects that serve existing properties and new development. Noteworthy projects are:

  • East Side Interceptor Rehabilitation — The portion of the sewer that traverses the National Arboretum has significant structural distress. Design is underway for the rehabilitation of the sewer, which will be completed in early FY2004. Construction is scheduled to start in the summer of 2004.
  • Infiltration/Inflow City Wide (excluding National Park Service areas) — This project corrects infiltration/ inflow problems throughout the City that have been identified as cost effective. This project was recently bid and awarded, with construction expected to be completed during FY2004.

TOPtop

Interceptor/Trunk Sewer/Force Sewers — $82.1 million

Capital Improvement Program

This program includes large diameter sewers that may be required to serve new development, replace undersized sewers, or replace or rehabilitate large diameter sewers that have reached their useful life or are in need of major repair. In addition, this category includes approximately $7 million in FY2004 for initial funding of capital projects that may be identified as part of the comprehensive assessment of the sewer system.

The current CIP contains several projects in this service area including:

  • Potomac Interceptor Rehabilitation - The Potomac Interceptor Sewer System is a 50- mile long sewer that provides conveyance of wastewater from areas in Virginia, Maryland and the District to Blue Plains. WASA has been working with our wholesale customers on a variety of capital projects to address odor control issues related to the Potomac Interceptor and to ensure the long- term structural integrity of this major sewer, including:
    • Potomac Interceptor Rehabilitation in Fairfax and Loudoun Counties — The capital improvement program includes $8.7 million to design and reconstruct portions of the interceptor in Fairfax and Loudoun Counties that are seriously deteriorated due to hydrogen sulfide corrosion. Design began in spring 2003, with construction beginning in the FY2004 and extending through FY2006.
    • General Potomac Interceptor Rehabilitation Projects — $1.3 million is included to repair other segments of the Potomac Interceptor as determined by a study that was completed to assess the condition of the pipeline. This includes manhole replacement and rehabilitation of miscellaneous structures along the length of the line. The design and bid documents are complete and construction will take place in FY2004.
  • Odor Control Projects:
    • Interim Odor Controls — As an interim step, WASA installed odor- absorbing chemicals and passive carbon filters in manholes at selected locations where problems have been observed. This interim project cost approximately $. 35 million and was completed in July 2000. These interim controls are continually maintained until the implementation of the permanent odor controls.
    • Permanent Odor Controls — WASA plans to install a permanent odor control system that includes a forced air/ activated carbon filter system. This project will cost approximately $10 million. The conceptual design was completed in FY2003. During the past three years, WASA has been seeking the requisite National Park Service permit, performing associated environmental assessments, and coordinating with the community. It is expected that the National Park Service will issue a Finding of No Significant Impact in early FY2004. The current schedules call for construction to begin in FY2004 and to be completed in FY2005.
  • Additional Tide Gate Structure Replacements — This new project recommends the study, design, and replacement of five additional tide gates at various locations that are impacted by high tides. Similar to the previous tide gate improvements project, this project involves the replacement of existing gates with elastomeric- type gates that more positively ensure closure. This design of this project is anticipated to start in FY2005, and construction would be completed in 2007.
  • Upper Potomac Interceptor Rehabilitation — This project involves the repair of a major portion of the trunk sewer. This project was delayed due to the National Park Service delays in permit issuance. The permit was received in FY 2003, and detailed design will start in FY2004.

TOPtop

Pumping Facilities — $20.2 million

This program includes projects required for the rehabilitation or replacement of existing wastewater pumping stations as well as projects for the engineering and construction of new wastewater pumping facilities as required. The current program includes projects to rehabilitate three existing wastewater pumping stations (Upper Anacostia, Earl Place, and Rock Creek pumping stations). The conceptual design of these pumping stations is completed, and the detailed design will take place in FY2004 and FY2005. Construction is expected to begin in FY2005 and be completed in FY2008.

TOPtop

Ongoing Sanitary Sewer Projects — $60.6 million

This area includes capital projects managed by the Department of Sewer Services including the replacement of sewer laterals and related capital improvements. The program also includes funding for the District of Columbia Department of Transportation (DDOT) road projects, which often require the relocation of sewers. Budget requirements are projected based on the best available information from DDOT.

TOPtop