AIR-GAP SEPARATION. A physical separation between the free flowing discharge end of a potable water supply pipeline and an open or nonpressure receiving vessel. An approved AIR-GAP SEPARATION shall be at least double the diameter of the supply pipe measured vertically above the overflow rim of the receiving vessel, in no case less than one inch (2.54 cm).
APPROVED. As used in reference to a water supply, a water supply that has been approved by the North Carolina Department of Environment, Health, and Natural Resources, or as used in reference to air-gap separation, a pressure vacuum breaker, a double check valve assembly, a double check detector assembly, a reduced pressure principle backflow prevention assembly, a reduced pressure principle detector assembly, or other backflow prevention assemblies or methods; or an approval by the Brunswick County or the town’s Water Department.
BACKFLOW. The undesirable reversal of flow of water or mixtures of water and other liquids, gases, or other substances into the distribution pipes of the consumer or public potable water system from any source or sources.
BACKFLOW PREVENTION ASSEMBLY - APPROVED. An assembly used for containment and/or isolation purposes that has been investigated and approved by Brunswick County and has been shown to meet the design and performance standards of the American Society of Sanitary Engineers (ASSE), the American Water Works Association (AWWA), or the Foundation for Cross-Connection Control and Hydraulic Research of the University of Southern California. To be approved, an assembly must be readily accessible for inline testing and maintenance, and shall successfully complete a one-year field evaluation within the Brunswick County water system. The type of assembly used should be based on the degree of hazard either existing or potential. The following are approved methods for backflow prevention:
(1) Double check detector assembly (fire system);
(2) Air gap;
(3) Reduced pressure principle assembly (RPZ);
(4) Double check valve assembly (DCVA);
(5) Reduced pressure principle-detector assembly (fire system);
(6) Pressure vacuum breaker (PVB).
BACKFLOW PREVENTION ASSEMBLY - UNAPPROVED. An assembly that has been investigated by Brunswick County and has been determined to be unacceptable for installation within the town's water system.
BACKFLOW PREVENTION ASSEMBLY TESTER - CERTIFIED. A person who has proven his competency to the satisfaction of the Water Department. Each person who is certified to make competent tests, or to repair, overhaul, and make reports on backflow prevention assemblies shall be
knowledgeable of applicable laws, rules, and regulations, and have qualifications acceptable to the Department, and must hold a certificate of completion from an approved training program in the testing and repair of backflow prevention assemblies.
BACKFLOW PREVENTION DEVICE - APPROVED. A device used for isolation purposes that has been shown to meet the design and performance standards of the American Society of Sanitary Engineers (ASSE) and the American Water Works Association (AWWA).
BACK-PRESSURE BACKFLOW. Any elevation in the consumer water system, by pump, elevation of piping, or steam and/or air pressure, above the supply pressure at the point of delivery which would cause, or tend to cause, a reversal of the normal direction of flow.
BACK-SIPHONAGE BACKFLOW. A reversal of the normal direction of flow in the pipeline due to a negative pressure (vacuum) being created in the supply line with the backflow source subject to atmospheric pressure.
CHECK VALVE - APPROVED. A check valve that is drip-tight in the normal direction of flow when the inlet pressure is at least one psi and the outlet pressure is zero. The check valve shall permit no leakage in a direction reverse to the normal flow. The closure element (for example, clapper, poppet, or other design) shall be internally loaded to promote rapid and positive closure. An approved check valve is only one component of an approved backflow prevention assembly (for example, pressure vacuum breaker, double check valve assembly, double check detector assembly, reduced pressure principle assembly, or reduced pressure detector assembly).
CONSUMER/CUSTOMER. Any person, firm, or corporation using or receiving water from the town's water system. In the absence of other parties or the failure of other parties to accept the responsibilities herein set forth, the owner of record shall be ultimately responsible.
CONSUMER’S POTABLE WATER SYSTEM. That portion of the privately owned potable water system lying between the point of delivery and point of use and/or isolation protection. This system will include all pipes, conduits, tanks, receptacles, fixtures, equipment, and appurtenances used to produce, convey, store, or use potable water.
CONSUMER’S WATER SYSTEM. Any water system commencing at the point of delivery and continuing throughout the consumer's plumbing system, located on the consumer's premises, whether supplied by a public potable water or an auxiliary water supply.
CONTAINMENT. Preventing the impairment of the public potable water supply by installing an approved backflow prevention assembly at the service connection.
CONTAMINATION. An impairment of the quality of the water which creates a potential or actual hazard to the public health through the introduction of hazardous or toxic substances or through the spread of disease by sewage, industrial fluids, or waste.
CROSS-CONNECTION. Any unprotected actual or potential connection or structural arrangement between a public or a consumer's water system and any other source or system through which it is possible to introduce any contamination or pollution, other than the intended potable water with which the system is supplied. Bypass arrangements, jumper connections, removable sections, swivel or change-over devices, and other temporary or permanent devices through which or because of which “backflow” can or may occur are considered to be cross-connections.
CROSS-CONNECTION - CONTROLLED. A connection between a potable water system and a non-potable water system with an approved backflow prevention assembly properly installed and maintained so that it will continuously afford the protection commensurate with the degree of hazard.
DEPARTMENT. The Town of Caswell Beach Water Department.
DOUBLE CHECK DETECTOR ASSEMBLY. A specially designed assembly composed of a line-size approved double check valve assembly with a specific bypass water meter and a meter-sized approved double check valve assembly. The meter shall register (in U.S. gallons) accurately for only very low rates of flow and shall show a registration for all rates of flow. This assembly shall only be used to protect against a non-health hazard (for example, pollutant).
DOUBLE CHECK VALVE ASSEMBLY. An assembly composed of two independently acting, approved check valves, including tightly closing shutoff valves attached at each end of the assembly and fitted with properly located test cocks. This assembly shall only be used to protect against a non-health hazard (for example, pollutant).
DUAL CHECK VALVE. A self-closing device designed to permit flow in one direction and close if there is a reversal of flow. A dual check valve is not an in-line testable device and is only allowed for residential use in three inch and one inch meter assemblies, excluding irrigation systems.
HAZARD, DEGREE OF. This term is derived from the evaluation of conditions within a system which can be classified as either a “pollutional” (non-health) or a “contamination” (health) hazard.
HAZARD, HEALTH. An actual or potential threat of contamination of a physical, hazardous or toxic nature to the public or consumer's potable water system to such a degree or intensity that there would be a danger to health.
HAZARD, NON-HEALTH. An actual or potential threat to the quality of the public or the consumer's potable water system. A NON-HEATH HAZARD is one that, if introduced into the public water supply system, could be a nuisance to water customers, but would not adversely affect human health.
HAZARD, POLLUTIONAL. An actual or potential threat to the quality or the potability of the public or the consumer's potable water system but which would not constitute a health or a system hazard, as defined. The maximum degree or intensity of pollution to which the potable water system could be degraded under this definition would cause a nuisance or be aesthetically objectionable or could cause minor damage to the system or its appurtenances.
HEALTH AGENCY. The North Carolina State Department of Environment and Natural Resources.
ISOLATION. The act of confining a localized hazard within a consumer's water system by installing approved backflow prevention assemblies. Disclaimer: The Department may make recommendations, upon facility inspection, as to the usages of isolation devices/assemblies, but does not assume or have responsibility whatsoever for installations.
POINT OF DELIVERY. Generally at the property line of the customer, adjacent to the public or private street where the county or town's Water Department's mains are located, or at a point on the customer's property where the meter is located. The customer shall be responsible for all water piping and control devices located on the customer's side of the point of delivery.
POLLUTION. An impairment of the quality of the water to a degree which does not create an actual hazard to the public health but which does adversely and unreasonably affect the aesthetic qualities of such waters for domestic use.
POTABLE WATER. Water from any source that has been investigated by the State Department of Environment and Natural Resources and which has been approved for human consumption.
PUBLIC POTABLE WATER SYSTEM. Any publicly or privately owned water system operated as a public utility, under a current State Department of Environment and Natural Resources permit, to supply water for public consumption or use. This system will include all sources, facilities, and appurtenances between the source and the point of delivery such as valves, pumps, pipes, conduits, tanks, receptacles, fixtures, equipment, and appurtenances used to produce, convey, treat, or store a potable water for public consumption or use.
REDUCED PRESSURE PRINCIPLE BACKFLOW PREVENTION ASSEMBLY. An assembly containing within its structure a minimum of two independently acting, approved check valves, together with a hydraulically operating, mechanically independent, pressure differential relief valve located between the check valves and at the same time below the first check valve. The first check valve reduces the supply pressure a predetermined amount so that during normal flow and at cessation of normal flow, the pressure between the checks is less than the supply pressure. In case of leakage of either check valve, the pressure differential relief valve, by discharge to atmosphere, shall operate to maintain the pressure between the checks less than the supply pressure. The unit shall include tightly closing shutoff valves located at each end of the assembly and each assembly shall be fitted with properly located test cocks. The assembly is designed to protect against a health hazard (for example, contaminant).
REDUCED PRESSURE PRINCIPLE DETECTOR ASSEMBLY. A specially designed assembly composed of a line-size approved reduced pressure principle backflow prevention assembly with a specific bypass water meter and a meter-sized approved reduced pressure principle backflow prevention assembly. The meter shall register, in U.S. gallons, accurately for only very low rates of flow and shall show a registration for all rates of flow. This assembly shall be used to protect against a health hazard (for example, contaminant).
SERVICE CONNECTIONS. The terminal end of a service connection from the public potable water system, for example, where the Department loses jurisdiction and sanitary control over the water at its point of delivery to the consumer's water system.
TOWN. The Town of Caswell Beach, North Carolina.
VACUUM BREAKIER - ATMOSPHERIC TYPE. Also known as the “non-pressure type vacuum breaker,” this term means a device containing a float-check, a check seat, and an air inlet port. The flow of water into the body causes the float to close the air inlet port. When the flow of water stops, the float falls and forms a check valve against backsiphonage and at the same time opens the air inlet port to allow air to enter and satisfy the vacuum. A shutoff valve immediately upstream may be an integral part of the device. An atmospheric vacuum breaker is designed to protect against a nonhealth hazard, isolation protection only, under a backsiphonage condition only.
VACUUM BREAKER - PRESSURE TYPE. An assembly containing an independently operating internally loaded check valve and an independently operating loaded air inlet valve located on the discharge side of the check valve. The assembly is to be equipped with properly located test cocks and tightly closing shutoff valves attached at each end of the assembly. This assembly is designed to protect against a health hazard (for example, contaminant) under a backsiphonage condition only.
WATER PURVEYOR. The owner or operator of a public potable water system, providing an approved water supply to the public. Brunswick County is the water purveyor for the Town of Caswell Beach. The Town of Caswell Beach is the water purveyor to its customers.
WATER SUPPLY - APPROVED. Any public potable water supply which has been investigated and approved by the State Department of Environment and Natural Resources. The system must be operating under a valid health permit. In determining what constitutes an approved water supply, the State Department of Environment and Natural Resources has reserved the final judgment as to its safety and potability.
WATER SUPPLY - AUXILIARY. Any water supply on or available to the premises other than Brunswick County's approved public potable water supply. These auxiliary waters may include water from another purveyor's public potable water supply or any natural source such as a well, spring, river, stream, and the like, “used water”, or industrial fluids. These waters may be polluted, contaminated, or objectionable and constitute an unacceptable water source over which the water purveyor does not have sanitary control.
WATER SUPPLY - UNAPPROVED. A water supply which has not been approved for human consumption by the State Department of Environment and Natural Resources.
WATER - USED. Any water supplied by a water purveyor from a public water system to a consumer's water system after it has passed through the point of delivery and is no longer under the control of the water purveyor.
(Res. passed 11-20-03)