For the purpose of this division, the following definitions shall apply unless the context clearly indicates or requires another meaning.
BACKFLOW. Any reverse flow of water, gas or any other substance back into the public water system of the city from any source other than the approved water supply.
(1) BACK PRESSURE BACKFLOW. Any elevation of pressure in the downstream piping system caused by pumps, elevation of piping, heat or steam and/or air pressure above the supply pressure at the point of consideration, which would cause a reversal of the normal direction of flow of water.
(2) BACKSIPHONAGE BACKFLOW. A reversal of the normal direction of flow of water in the pipes due to a negative pressure (vacuum) being created in the supply line with the backflow source subject to atmospheric pressure. This can occur because of water main breaks or during fire suppression events.
BACKFLOW/CROSS-CONNECTION ORC. An employee of the city, trained and certified by the state as a cross-connection control operator in responsible charge, designated to administer and enforce this chapter.
BACKFLOW PREVENTION ASSEMBLY (APPROVED). An assembly that has been investigated and approved by the Backflow/Cross-Connection ORC and has been approved to meet the design and performance standards of the American Society of Sanitary Engineers (ASSE), the American Water Works Association (AWWA), the North Carolina State Plumbing Code, and has been tested and approved for specific applications by the University of Southern California Foundation for Cross-Connection Control and Hydraulic Research (USC FCCCHR). FM (Factory Mutual) and Underwriters Laboratory (UL) approvals shall be required for backflow prevention assemblies installed on fire suppression lines. Installation on a potable water system must use lead free devices.
(1) AIR GAP (FIXED). A permanently fixed, unobstructed vertical distance through the atmosphere between the lowest opening from any pipe or faucet supplying water from any source to a tank, plumbing fixture, or other device and the flood level rim of the device. An approved air gap separation shall be at least double the diameter of the supply pipe. In no case shall the air gap separation be less than two inches. An approved air gap may be considered as a backflow prevention assembly.
(2) DOUBLE CHECK VALVE ASSEMBLY. An assembly composed of two single, independently operating, approved check valves, plumbed in series. The assembly must include four resilient-seated test cocks that are properly located for testing the assembly and two tightly closing shut- off valves located at each end of the assembly.
(3) DOUBLE CHECK DETECTOR ASSEMBLY. An assembly composed of an approved double check valve assembly with a bypass water meter and a meter-sized approved double check valve device. The meter shall register accurately for very low flow rates and shall register all flow rates. The check valves shall allow for water to flow through the water meter prior to flowing through the larger assembly. This shall be for the purpose of detecting leaks or usage on fire suppression water systems.
(4) DUAL CHECK VALVE DEVICE. A backflow prevention device comprised of two independently operating, approved check valves, plumbed in series. The device is not testable and is generally installed downstream from a water meter and is used for the containment of single family water services as part of a residential backflow prevention program.
(5) PRESSURE VACUUM BREAKER ASSEMBLY. A device containing an independently operating spring loaded check valves and an independently operated spring loaded air inlet valve located on the discharge side of the check valve. The device includes tightly closing shut-off valves on each side of the assembly and two properly located test cocks for the testing of the assembly.
(6) REDUCED PRESSURE ZONE ASSEMBLY. An approved, properly functioning assembly containing two, independently operating approved check valves plumbed in series, with a hydraulically operating, mechanically independent pressure differential relief valve located between the check valves that discharges to atmosphere. The ASSEMBLY must include four resilient-seated test cocks that are properly located for testing the assembly and two tightly closing shut- off valves located at each end of the assembly.
(7) REDUCED PRESSURE DETECTOR ASSEMBLY. An assembly composed of an approved reduced pressure zone backflow prevention assembly with a bypass water meter and meter-sized approved reduced pressure zone device. The meter shall register accurately for very low flow. The water flowing through the meter shall be protected to same level as the water through the main assembly. The check valves shall allow for water to flow through the water meter prior to flowing through the larger assembly. This shall be for the purpose of detecting leaks or usage on fire suppression water systems.
CERTIFIED BACKFLOW PREVENTION ASSEMBLY TESTER. Any individual person who holds a certificate of completion from a certified training program in the testing and repair of backflow prevention assemblies and cross-connection control. The certification school must be approved by the Backflow/Cross-Connection ORC for the city and based on the quality of training provided as compared to NC AWWA and NCRWA standards.
CONSTRUCTION METER. A water meter assembly that includes a Reduced Pressure Zone backflow preventer for the protection of the potable water system, usually three-fourth’s-inch by five- eighth’s-inch designated for the purpose of providing temporary waster service for a construction site. It may be set up to take advantage of an existing water connection or be connected to a fire hydrant and shall have a three-fourth’s-inch hose bib connection.
CONTAINMENT. The prevention of backflow from a non-potable system utilizing an approved, properly functioning backflow prevention assembly which is installed, operated, and maintained in accordance with the provisions of this division.
CONTAMINATION. An impairment of the quality of the water to a degree that it creates an actual hazard to the public health through poisoning or through the spread of disease.
CROSS-CONNECTION. Any actual or potential connection or piping arrangement between a potable water supply and any other non-potable source or system whereby water or other liquids, mixtures, or substances may flow into or enter the potable water supply system.
HAZARD (HEALTH/HIGH). A potential threat of contamination to the public water system or to a water service customer’s potable water system that could cause serious illness or death.
HAZARD (IMMINENT). An immediate threat of contamination to the public water system that could cause serious illness or death.
HAZARD (NON-HEALTH/LOW). An actual or potential threat of damage to the physical components comprising the public water system or to a water service customer’s potable water system, or of pollution to the public water system or to a water service customer’s potable water system.
HOMEOWNER. An individual who resides on the property that he or she owns by proper title and/or deed. The owner-occupant of a home.
HYDRANT METER. A water meter designed to be connected to a fire hydrant for the purpose of obtaining water on a temporary basis where no regular water connection is available that will perform the purpose needed. This device should include a Reduced Pressure Zone (RPZ) backflow preventer to protect the potable water system from contamination. This assembly shall be fitted with a two and one- half-inch fire hose connection.
ISOLATION. The prevention of backflow in which a backflow preventer, such as a hose bib or an atmospheric vacuum breaker, is located to correct a cross-connection at a specific location on a private potable water system rather than at a water service connection. This protects the drinking water in the building and is covered by the State Plumbing Code.
OWNER. Any person who has legal title to, or license to operate or habitat in, a property upon which a cross-connection inspection is to be made or upon which a cross-connection is present.
POLLUTION. An impairment of the quality of the potable water to a degree that does not create a hazard to public health but that does adversely and unreasonably affect the aesthetic qualities of such potable water for domestic use.
POTABLE WATER. Water from any source which has been approved for human consumption by the State of North Carolina, Department of Environmental Quality, Water Resources Division, and the Public Water Supply Section.
PERSON. Any individual, partnership, company, public or private corporation, political subdivision or government agency or any other legal entity.
PRIVATE WATER SYSTEM. Any water system located on the water service customer’s premise, whether supplied by public potable water or an auxiliary water supply. The SYSTEM or SYSTEMS may be either a potable water system or an industrial piping system.
PUBLIC WATER SYSTEM. The potable water system owned and operated by the city. This includes all storage tanks, distribution mains, lines, pipes, connections, fixtures and other facilities, conveying potable water from the water treatment plants to the service connections of each water service customer.
SERVICE CONNECTION. The terminal end of a service connection from the public potable water system, immediately after the water meter, (e.g., where the water purveyor loses jurisdiction and sanitary control over the water at its point of delivery to the water service customer’s private water system).
USED WATER. Any water supplied by a water purveyor from a public potable water system to a water service customer’s private water system after it has passed through the point of delivery and is no longer under the control of the water purveyor.
WATER SERVICE CUSTOMER. Any person, firm, or corporation receiving water from the City by way of a water service connected to the city’s public water system.
WATER PURVEYOR. Owner or operator of a public potable water system providing approved potable water supply to the public.
WATER SUPPLY (AUXILIARY). Any water supply on or available to the water customer’s premises other than the water purveyor’s public potable water system. The auxiliary water may include water from another purveyor’s public potable water system or any natural source such as a well, spring, river, stream, etc., and used or objectionable.
WATER SUPPLY (UNAPPROVED). Any water supply, which has not been approved for human consumption by the State of North Carolina, Department of Environmental Quality, Water Resources Division, or the Public Water Supply Section.
(Ord. passed 6-19-18; Am. Ord. passed 1-21-20)