D.C. Mun. Regs. tit. 12, r. 12-F603

Current through Register Vol. 71, No. 44, November 1, 2024

Rule 12-F603 - WATER SERVICE

Strike Section 603.1 of the International Plumbing Code in its entirety and insert a new Section 603.1 into the Plumbing Code in its place to read as follows:

603.1

Size of water service pipe. The water service pipe shall be sized to supply water to the structure in the quantities and at the pressures required in this code. New water service pipe shall be not less than 1 inch (25.4 mm) in nominal size diameter.

Insert new Sections 603.3, 603.3.1, 603.3.2 and 603.3.3 into the Plumbing Code to read as follows:

603.3

Water service piping protection. Water service piping shall be protected against backflow in accordance with Sections 603.3.1 through 603.3.3.

603.3.1

Water service piping backflow prevention. A backflow preventer shall be installed on the water service pipe, downstream of the water meter, in compliance with Table 603.3.1, for every new water service, and for existing water services as required by Section 603.3.3. Backflow preventers shall be installed in accordance with manufacturer's installation instructions and DC Water design specifications, and shall be located upstream from any served water outlet.

603.3.2

High risk non-residential structure. Any building, structure or campus that is or contains a facility hereafter classified as a high risk non-residential structure shall be required to install a reduced pressure principle backflow prevention assembly conforming to ASSE 1013 on the water service connection. High risk non-residential facilities include, but are not limited to, hospitals, hemoglobin dialysis centers, funeral homes or mortuary facilities, chemical manufacturing plants, car wash facilities, sewage treatment plants, auxiliary water supply systems, wells, dry cleaning plants, breweries, distilleries, laboratories, facilities where radioactive materials are handled, and facilities with a water reuse system.

603.3.3

Existing water service piping. Installation of a backflow preventer in an existing water service pipe shall be required only in the following cases:

1. Construction of a new structure reusing the existing service.

2. Alteration of the existing water distribution system of the structure affecting fixtures that in aggregate account for more than 75 percent of the demand load of the existing installed system, calculated in accordance with Section 604.3, not including minor piping adjustments for fixture replacements.

3. Addition to the existing water distribution system of the structure that will result in an increase of more than 50 percent in the demand load of the existing installed system, calculated in accordance with Section 604.3.

4. The served existing structure has been or is heretofore classified as a high risk non-residential structure.

5. When the existing water service pipe is replaced.

6. When the meter setter is replaced.

Insert new Table 603.3.1 in the Plumbing Code to read as follows:

TABLE 603.3.1 WATER SERVICE BACKFLOW PREVENTION Water Service Backflow Preventers

Facility type	Service Size	Type	Location Note a
Residential or nonresidential	5/8", 3/4:" 1", 1 1/2" and 2"	ASSE 1024 Dual Check Valve	On the discharge side of meter yoke Note b
Non-residential	3" and larger	ASSE 1015 Double Check Backflow Prevention Assembly	Inside facility, within 10 feet of water service point of entry prior to any pipe branching
High Risk Nonresidential	Any	ASSE 1013 Reduced Pressure Principle Backflow Prevention Assembly

Fire Protection Backflow Preventers

Water Treatment	Type	Location Note a
No chemical additives	ASSE 1015 Double Check Fire Protection Backflow Prevention Assembly ASSE 1048 Double Check Detector Fire Protection Backflow Prevention Assembly	Inside facility, within 10 feet of water service point of entry
Treated with chemical Additives	ASSE 1013 Reduced Pressure Principle Backflow Prevention Assembly ASSE 1047 Reduced pressure detector fire protection backflow prevention assembly

For SI: 1 inch = 25.4 mm, 1 ft = 304.8 mm, 1 pound per square inch = 6.895 kPa.

a - Backflow preventers shall always be located upstream from any water outlet.

b - Where inlet pressure to meter yoke is less than 42 psi, it is acceptable to locate the domestic backflow preventers inside the facility, within 10 feet of water service point of entry prior to any unprotected pipe branching.

D.C. Mun. Regs. tit. 12, r. 12-F603

Final Rulemaking published at 67 DCR 5679 (5/29/2020)