Applicants can request a Water and Sewer Availability Letters which will verify that water and sewer service is, or will be available, to serve a particular building or development. In some cases, there is more than one water main or sewer within the street by a site. This letter will advise the applicant what water mains or sewers will be available for their project. DCWASA does not allow any connections to 16-inch and larger water mains unless it will create a severe hardship upon the applicant. DCWASA will not allow any connections to alley water mains or sewers, unless the property does not have direct access to public roads with public water mains or sewers. The applicant's lending institution normally needs this letter. Applicants should request an availability letter during the early stages of a project, before having all the information that is required to obtain a Water and Sewer Availability Certificate. DCWASA charges $300 for each availability letter.

The applicant must send a letter to the Documents and Permits office at 5000 Overlook Avenue, SW Washington DC 20032. This letter must include the following:

1. The address of the proposed building or the existing to be renovated.
2. The square and lot numbers.
3. The height of the building.
4. The closest cross streets to the building.
5. The peak water demand and peak storm water and sanitary flows.
6. A check for $300 made out to DCWASA.

When the Documents and Permits Section (DPS) receives a request for a Water and Sewer Adequacy Letter, the DPS reviews the water and sewer counter maps to verify that water and sewer service is available. If the water main and sewer(s) in the area can serve or can be extended to serve a "normal" building (single-family house or building with less than 4 floors), then an adequacy letter is written to the applicant. If the request is for other than a "normal" building (more than 3 floors), then DCWASA will conduct a hydraulic analysis to verify that the existing water main and sewers can support the development. If DCWASA determines that the water main and sewer(s) are adequate to serve the proposed building, DCWASA will send an adequacy letter to the applicant. If DCWASA determines that a water main or sewer is not adequate, then DCWASA will send a letter to the applicant explaining the reasons why the pipe(s) adjacent to the property are not adequate for their proposed project. DCWASA will explain in this letter what course of action will be necessary to obtain adequate water and sewer service for the project.