District of Columbia Water and Sewer Authority

The Environmental Assessment for the Long-Term Odor Control Program provides decision-makers and the public with information and analysis on the proposed project. The purpose of this document is to disclose the expected effects to the environment of implementing four odor control facilities associated with the proposed Potomac Interceptor (PI) odor control system. The four proposed facility sites are located within the jurisdiction of the Chesapeake and Ohio Canal Historical Park (C&O Canal) and the George Washington Memorial Parkway, both of which are divisions of the National Park Service (NPS). The intent of the proposed long-term odor abatement program is to mitigate the human impacts associated with odorous sewer gases venting from the PI.

Environmental Assessments are governed by the National Environmental Policy Act (NEPA) of 1969 (Pub. L. 91-190, 42 U.S.C. 4321-4347, January 1, 1970, as amended by Pub. L. 94-52, July 3, 1975, Pub. L. 94-83, August 9, 1975, and Pub. L. 97-258, § 4(b), Sept. 13, 1982). The purpose of NEPA as described in the Act is, "To declare a national policy which will encourage productive and enjoyable harmony between man and his environment; to promote efforts which will prevent or eliminate damage to the environment and biosphere and stimulate the health and welfare of man; to enrich the understanding of the ecological systems and natural resources important to the Nation; and to establish a Council on Environmental Quality."

Click here to view information on the National Environmental Policy Act (NEPA) at the EPA's website.

The long-term odor control program was developed based on shared goals with theNPS and other project stakeholders. Since there has also been strong public interest in this project, many community groups, recreational clubs and environmental interest groups were informed of the proposed project and solicited for input. A consistent and primary theme related to the odor abatement program was that odors from the PI should be significantly reduced year round and that odors should be mitigated directly along the PI.

The objectives of the proposed action include:

• Providing long-term control of odors in specific areas of the PI by a practical, reliable and effective means; and
• Maintaining the integrity of the reinforced concrete sewer pipes by minimizing interference with the design function of the PI vent structures and sewer airflow dynamics thereby limiting the formation of corrosive conditions.

The Environmental Assessment for the Long-Term Odor Control Program has been evaluated by stakeholder groups and with the cooperation and support of agencies of the NPS.

Download the complete Potomac Interceptor Environmental Assessment (PDF 2.8 mb) here.