District of Columbia Water and Sewer Authority

Groundwater and surface runoff may only be discharged to the combined sewer system, storm sewer, or to an outfall that discharges to a natural stream/river. It is illegal to discharge ground water to the separate sanitary sewer system.

DC Water allows residents, businesses, and government agencies to discharge groundwater (e.g., construction/dewatering projects, groundwater remediation systems, etc.) or other temporary water discharges (e.g., power wash runoff, hydro-demolition wastewater, etc.) to the public sewer system on a case-by-case basis.

The discharge standards apply to all temporary dischargers. DC Water currently has no standards for volatile organics, however, to determine if volatile organics require pretreatment, DC Water compares water quality data to published literature values in EPA's Guidance to Protect POTW Workers from Toxic and Reactive Gases and Vapors.

Applicants wanting to discharge groundwater or other temporary discharges to the public sewer system must submit a Temporary Discharge Authorization(TDA)PermitApplication to DC Water's Pretreatment Coordinator.

If the groundwater is not contaminated and the discharge location is near a separate storm sewer system (i.e., not part of the combined sewer system), then the applicant will be required to direct the discharge to the storm sewer. To determine if the project is in a separate storm sewer area contact DC Water's Documents and Permits Office at 202-787-2057.

If the groundwater is to be discharged to the combined sewer system, then DC Water will determine the conditions under which a TDA Permit will be issued and whether metering and fees are required.

• Temporary Discharge Authorization PermitApplication (no application fee)
• Chemical analysis of the groundwater
• Copy of any engineering plans/documents
• Site map of proposed discharge location

The application package shall be mailed or delivered to the

Pretreatment Coordinator at DC Water
Department of Wastewater Treatment
5000 Overlook Ave., SW
CMF 2nd Floor
Washington, DC 20032

Telephone: 202-787-4177

For expeditious processing, a copy of the application package may also be faxed to 202-787-4226 (with hard copy to follow in the mail).

The permit is valid for up to two years. A permit may be extended by written request if within the two year permit term. A new permit application must be submitted prior to the expiration date if the discharge has not been completed within the two year permit term.

There is no cost for the permit application or the discharge of groundwater. However, if DC Water determines that the discharge must be metered, the permittee will be charged a fee for the metered discharge amount.

The Permittee is required to contact the following departments:

1. DC Water's Customer Service Billing and Measurement Office must be notified to identify metering requirements and sewer use fees. Contact the Metering Manager at 202-612-3485.
2. DC Water's Department of Sewer Services must be notified of the discharge location. Contact the Inspection Manager at 202-535-2600.
3. If the site is in a separate storm sewer area and the discharge contains groundwater or surface water, the applicant must contact the DC Department of Environmental Water Quality Division at 202-535-2190 to inquire about discharging to the storm sewer.