12VAC5-590-1110. Distribution system materials.
Pipe, fittings, joints, valves, hydrants, and coatings shall conform to AWWA standards.
Statutory Authority
§§ 32.1-12 and 32.1-170 of the Code of Virginia.
Historical Notes
Derived from VR355-18-012.01 § 3.48, eff. August 1, 1991; amended, Virginia Register Volume 37, Issue 20, eff. June 23, 2021.
12VAC5-590-1120. Minimum pipe size.
A. The minimum size pipe for water distribution mains shall be four inches in diameter. Pipes of lesser diameter may be used in the following instances:
1. When the run is less than 300 feet, two-inch diameter pipe may be used.
2. When the run is less than 600 feet but more than 300 feet, three-inch diameter pipe may be used.
3. Any departure in sizing shall be justified by hydraulic analysis and future water demands.
B. Fire hydrants shall not be connected to water mains that are not designed to carry fire flows. Connection of a fire hydrant to a pipe of less than six inches in diameter is prohibited.
C. Where a noncommunity waterworks serves a single building, the plumbing shall be in accordance with the USBC. Where a noncommunity waterworks serves two or more buildings, the pipe shall be of sufficient size to provide adequate flow and pressure in order to meet the system demands.
Statutory Authority
§ 32.1-12 and 32.1-170 of the Code of Virginia.
Historical Notes
Derived from VR355-18-012.02 § 3.49, eff. August 1, 1991; amended, Virginia Register Volume 37, Issue 20, eff. June 23, 2021.
12VAC5-590-1130. Distribution system design.
A. Dead-ends should be minimized by the looping of water mains.
B. Where dead-end water mains occur, a means of effective flushing shall be provided.
C. No flushing device shall be directly connected to any sewer.
Statutory Authority
§§ 32.1-12 and 32.1-170 of the Code of Virginia.
Historical Notes
Derived from VR355-18-012.03 § 3.50, eff. August 1, 1991; amended, Virginia Register Volume 37, Issue 20, eff. June 23, 2021.
12VAC5-590-1140. Installation and testing of water mains.
A. Adequate supports and restraints shall be provided for all pipes.
B. A continuous and uniform bedding shall be provided in the trench for all buried pipe.
C. Stones and rocks found in the trench shall be removed to a depth of at least six inches below the bottom of the pipe and selected fill bedding provided.
D. Installed pipe shall be pressure-tested and meet allowable leakage as specified in accordance with AWWA Standards C600-17, C604-17, and C605-13, where applicable.
E. Any plastic or other nonmetallic pressurized pipe installed underground shall be provided with a material conductive of electricity or some other means of locating the buried pipe.
Statutory Authority
§§ 32.1-12 and 32.1-170 of the Code of Virginia.
Historical Notes
Derived from VR355-18-012.04 § 3.51, eff. August 1, 1991; amended, Virginia Register Volume 37, Issue 20, eff. June 23, 2021.
12VAC5-590-1150. Separation of water mains and sanitary sewers.
A. The following factors shall be considered in providing adequate separation of water mains and sanitary sewers:
1. Materials and types of joints for water and sanitary sewer mains;
2. Soil conditions;
3. Service branch connections into the water main and sanitary sewer mains;
4. Compensating variations in the horizontal and vertical separations;
5. Space for repairs and alterations of water and sanitary sewer mains;
6. Offsetting of pipes around manholes; and
7. Identification of the physical restraints preventing normal separation.
B. Parallel installation of water mains and sanitary sewers.
1. Under normal conditions, water mains shall be laid at least 10 feet horizontally from a sanitary sewer or sewer manhole. The distance shall be measured edge-to-edge.
2. Under unusual situations when local conditions prevent a horizontal separation of 10 feet, the water main may be laid closer to a sanitary sewer or sewer manhole provided that:
a. The bottom (invert) of the water main shall be at least 18 inches above the top (crown) of the sanitary sewer;
b. Where this vertical separation cannot be obtained, the sanitary sewer shall be constructed of water distribution pipe and pressure tested in place in accordance with 12VAC5-590-1110 and 12VAC5-590-1140;
c. The department may approve concrete encasement of the water main or other physical barrier;
d. The sewer manhole shall be of watertight construction and tested in place; and
e. No water pipes shall pass through or come into contact with any part of a sewer manhole.
C. Crossing of water mains and sanitary sewers.
1. Under normal conditions, water mains crossing sanitary sewers shall be laid to provide a separation of at least 18 inches between the bottom of the water main and the top of the sanitary sewer whenever possible.
2. Under unusual situations when local conditions prevent a vertical separation described in subdivision C 1 of this section, the following construction shall be used:
a. Sanitary sewers passing over or under water mains shall be constructed of the materials described in subsection B of this section and shall be constructed to a point 10 feet beyond and on each side of the crossing; and
b. Water mains passing under sanitary sewers shall, in addition, be protected by providing:
(1) A vertical separation of at least 18 inches between the bottom of the sanitary sewer and the top of the water main;
(2) Adequate structural support for the sanitary sewers to prevent excessive deflection of the joints and the settling on and breaking of the water main; and
(3) That the length of the water main be centered at the point of the crossing so that joints shall be equidistant and as far as possible from the sanitary sewer.
D. The minimum horizontal separation distance between water mains and septic tanks and drainfields, measured edge-to-edge, shall be 10 feet. Greater separation distances shall be provided wherever practical.
E. Water mains shall be located a safe horizontal distance from sources of contamination not already mentioned in this section, such as sewage treatment works and industrial complexes. The owner's engineer shall contact the department to determine the safe separation distances.
Statutory Authority
§§ 32.1-12 and 32.1-170 of the Code of Virginia.
Historical Notes
Derived from VR355-18-012.05 § 3.52, eff. August 1, 1991; amended, Virginia Register Volume 37, Issue 20, eff. June 23, 2021.
12VAC5-590-1160. Valve, air relief, meter, and blowoff chambers.
A. Standard fire hydrants or blowoffs shall be considered to enable removal of sediment and air accumulations.
B. Drains in chambers or pits that contain valves, blowoffs, meters, or other appurtenances to a distribution system shall not be connected directly to any storm drain or sanitary sewer, nor shall blowoffs or air relief valves be connected directly to any sanitary sewer.
C. Chambers or pits shall be drained to the surface of the ground where they are not subject to flooding by surface water or to absorption pits located above the seasonal groundwater table elevation. The backfill material for the water main may serve as an absorption pit if granular embedment material is laid from the pipe bedding up through the final backfill layer for the entire length of pipe in the chamber. Sump pumps may be used where other means are not practicable.
D. Chambers or pits shall be designed to facilitate air-valve inspection and servicing.
E. Air relief and blowoff piping.
1. The open end of an air relief pipe shall be extended from the manhole or enclosing chamber to a point at least one foot above ground and provided with a screened, downward facing elbow. The exposed pipe and appurtenances shall be protected from vandalism and other damage.
2. When an aboveground extension is not practical or desired, the open end of the air relief pipe or blowoff shall be extended.
a. Where the pit or chamber is provided with proper drainage and is not otherwise subject to high groundwater levels, surface flooding, ponding, and contaminant or pollutant spills, the open end may be provided with a screened, downward facing elbow. The valve chamber or pit shall be vented to provide sufficient air flow to allow proper operation of the air valve. Air valves fitted with a smooth vent port and screened hood are allowable under these conditions.
b. Where the pit or chamber is not properly drained or is otherwise subject to high groundwater levels, surface flooding, ponding, and contaminant or pollutant spills, a manually operated valve or blowoff shall be used and the open end shall be fitted with a watertight cap or other means to prevent contamination from entering the pipe and valve.
c. The installation and testing specifications shall require field verification by the owner's engineer of the groundwater elevation and surface water drainage, as needed in circumstances or situations where this is of potential concern, before placement of the pit or chamber.
Statutory Authority
§ 32.1-12 and 32.1-170 of the Code of Virginia.
Historical Notes
Derived from VR355-18-012.06 § 3.53, eff. August 1, 1991; amended, Virginia Register Volume 37, Issue 20, eff. June 23, 2021.
12VAC5-590-1170. Hydrants.
A. Fire hydrants.
1. To avoid cross-connection and contamination, dry barrel fire hydrants:
a. Should be located in areas that are not subject to high groundwater, flooding, surface water ponding, and contaminant or pollutant spills. When this is not practical, consideration shall be given to:
(1) Piping the drain port to daylight with screening on the end of the pipe; or
(2) Plugging the drain port and marking the hydrant for seasonal dewatering.
b. Shall comply with the ANSI/AWWA C502-18 standard, to include drain ports that are physically isolated from the drinking water system by the hydrant stem valve; and
c. Shall be drained to the ground surface or to a dry well provided exclusively for this purpose. Fire hydrant drains shall not be connected to sanitary sewers or storm drains.
2. Fire hydrants shall be connected only to water mains adequately designed for fire flows in accordance with the requirements of 12VAC5-590-1120 B.
B. Yard hydrants.
1. Shall have a hose connection vacuum breaker, meeting ASSE 1011-2017 or ASSE 1052-2016, if the hydrant has hose threads and is not already protected with an integral vacuum breaker.
2. To avoid cross-connection and contamination, yard hydrants installed in areas subject to high groundwater, flooding, contaminant, or pollutant spills or in areas where surface water ponds shall:
a. Meet ASSE 1057-2012, Performance Requirements for Freeze Resistant Sanitary Yard Hydrants with Backflow Protection; or
b. Have hydrant drain ports that are piped to daylight with screening on the end of the pipe; or
c. Be contained from the rest of the distribution system by a backflow prevention assembly suitable for a high hazard.
3. Frost-proof yard hydrants with weep holes draining below grade are allowed provided they are not installed in areas subject to high groundwater, to flooding, or to contaminant or pollutant spills or in areas where surface water ponds.
C. Hydrants and flushing devices not designed for fire protection may be connected to pipe of less than six inches in diameter, consistent with 12VAC5-590-1120 A.
Statutory Authority
§§ 32.1-12 and 32.1-170 of the Code of Virginia.
Historical Notes
Derived from VR355-18-012.07 § 3.54, eff. August 1, 1991; amended, Virginia Register Volume 37, Issue 20, eff. June 23, 2021.
12VAC5-590-1180. Surface water crossings.
A. Surface water crossings, both over and under water, present special challenges and shall be discussed with the department before project documents are prepared.
B. Aerial water crossings. The pipe above water crossings shall be:
1. Adequately supported;
2. Protected from freeze damage;
3. Accessible for repair or replacement; and
4. Above the 100-year flood elevation.
C. Under water crossings.
1. The pipe shall be of special construction, suitable to the method of installation and having flexible watertight joints.
2. Where rigid pipe is used, valves and taps shall be provided at both ends of the water crossing so that the section can be isolated for tests or repair; the valves and taps shall be easily accessible and not subject to flooding.
Statutory Authority
§§ 32.1-12 and 32.1-170 of the Code of Virginia.
Historical Notes
Derived from VR355-18-012.08 § 3.55, eff. August 1, 1991; amended, Virginia Register Volume 37, Issue 20, eff. June 23, 2021.
12VAC5-590-1190. (Repealed.)
Historical Notes
Derived from VR355-18-012.09 § 3.56, eff. August 1, 1991; repealed, Virginia Register Volume 37, Issue 20, eff. June 23, 2021.
12VAC5-590-1200. (Repealed.)
Historical Notes
Derived from VR355-18-012.10 § 3.57, eff. August 1, 1991; repealed, Virginia Register Volume 37, Issue 20, eff. June 23, 2021.
12VAC5-590-1210. Disinfection and testing of water mains.
A. All water mains shall be disinfected in accordance with AWWA Standard C651-14 before being placed in operation. The disinfection of the mains shall be repeated until it is determined by bacteriological testing that the water is free of coliform bacteria.
B. Project documents shall provide the details of the procedure and include the disinfectant application technique, dosage, contact time, method of testing the results of the procedure, and use or disposal of the disinfecting water.
Statutory Authority
§§ 32.1-12 and 32.1-170 of the Code of Virginia.
Historical Notes
Derived from VR355-18-012.11 § 3.58, eff. August 1, 1991; amended, Virginia Register Volume 37, Issue 20, eff. June 23, 2021.
12VAC5-590-1220. Pipe cover.
All buried distribution pipe shall be provided with sufficient earth or other suitable cover or encasement to prevent from freezing and provide protection from damage by external forces.
Statutory Authority
§§ 32.1-12 and 32.1-170 of the Code of Virginia.
Historical Notes
Derived from VR355-18-01212 § 3.59, eff. August 1, 1991; amended, Virginia Register Volume 37, Issue 20, eff. June 23, 2021.
12VAC5-590-1230. Service connection metering.
A. All new service connections in community waterworks shall be metered.
B. Water pipe and appurtenances between the water main and the service connection shall conform to all applicable codes.
Statutory Authority
§§ 32.1-12 and 32.1-170 of the Code of Virginia.
Historical Notes
Derived from VR355-18-01213 § 3.60, eff. August 1, 1991; amended, Virginia Register Volume 37, Issue 20, eff. June 23, 2021.
12VAC5-590-1235. Water loading stations.
A. The station and its piping and valving arrangement shall be designed to prevent unauthorized use, tampering, and vandalism.
B. An air gap or RPZ assembly shall be provided on the potable water fill connection to prevent backflow into the waterworks.
C. The piping and valving arrangement shall prevent contaminants from being transferred from a hauling tank or vessel to others subsequently using the water loading station.
D. Hoses used to fill potable water tanks and vessels shall be approved for potable water contact.
E. Hoses shall not come into contact with the ground or other contaminated surface and shall otherwise be handled, maintained, and stored in a manner to prevent contamination.
Statutory Authority
§§ 32.1-12 and 32.1-170 of the Code of Virginia.
Historical Notes
Derived from Virginia Register Volume 37, Issue 20, eff. June 23, 2021.