§ 25-137. Definitions.

Air gap separation: An 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 receptacle. 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 one inch. An approved, air gap separation is an effective method to prevent backflow in certain instances (specific applications only) and shall be considered as a backflow prevention assembly.

Atmospheric vacuum breaker: A device used to prevent back-siphonage which is designed so as not to be subject to static line pressure.

Backflow: Any reverse flow of water, gas or any other liquid substance or combination into the public water system from any source due to an unprotected cross-connection.

Backflow prevention assembly—approved: An assembly that has been investigated and approved by Salisbury-Rowan Utilities (SRU) as meeting the design and performance standards of the American Society of Sanitary Engineers (ASSE), the American Water Works Association (AWWA), and the Foundation for Cross Connection Control and Hydraulic Research of the University of Southern California.

Backpressure: Any elevation of pressure in the down stream piping system caused by pumps, elevation of piping, 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.

Back-siphonage: 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.

Certified tester: Any individual person who has proven his/her competency to test, repair and maintain backflow prevention assemblies. This person must hold a certificate of completion from a certified training program in the testing and repair of backflow prevention assemblies and cross-connection control, and must be on SRU's approved list.

City of Salisbury: For the purpose of this article, the City of Salisbury shall be defined as Salisbury-Rowan Utilities.

Consumer/customer: Any person, firm, corporation, or government agency using or receiving potable water from Salisbury-Rowan Utilities' public water system legally or equitably responsible for the payment of charges for water or sewer service to any premises.

Containment: Preventing the impairment of the potable water supply by installing an approved, properly functioning backflow prevention assembly which is installed, operated and maintained in accordance with the provisions of this article.

Contamination: The term shall mean 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 actual or potential connection or piping arrangement between a public or a consumer's potable water system and any other source or system through which it is possible to introduce into any part of the potable system any used water, industrial fluids, gas or substance which could be harmful or hazardous to the public health.

Double check valve assembly: An assembly composed of two (2) single, independently acting, approved check valves, including tightly closing shut-off valves located at each end of the device and suitable connections for testing the water tightness of each check valve.

Dual check valve: A device composed of two (2) single, independently acting, approved check valves. This is classified as a backflow device, not an assembly, and cannot be in-line tested.

Hazard-degree: The evaluation of a hazard within a private water system as low, moderate, severe, or imminent.

Hazard—imminent: An actual threat of contamination to the public water system that could cause serious illness or death.

Hazard—low: Low potential for pollution or contamination of a potable water system and low potential for damage to the physical components comprising a potable water system.

Hazard—moderate: Moderate potential for pollution of a potable water system or moderate potential for damage to the physical components comprising a potable water system.

Hazard—severe: Moderate potential for contamination of a potable water system or high potential for pollution of a potable water system.

Inspection: A visual examination of the backflow prevention assembly installation and service connection by SRU, Rowan County, or both to insure that the installation is in compliance with all regulations.

Isolation: The act of confining a localized hazard within a consumer's/customer's water system by installing approved backflow prevention assemblies.

Meter services supervisor: A qualified and certified employee of the city, or his/her designee, designated by SRU management to administer and enforce the provisions of this article.

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 such water for domestic use.

Potable water: Water from any source which has been approved for human consumption by the appropriate agency of the State of North Carolina, Salisbury-Rowan Utilities and/or Local Health Agencies.

Pressure vacuum breaker: An assembly suitable for continuous pressure, to be used to provide protection against back-siphonage.

Private distribution system: Any private water system which has a master meter and multiple sub-meter units serving individual units on a private parcel. This is a multiple meter system with private water mains not owned or operated by SRU.

Private water system: Any water system which is not owned or operated by SRU and which is located on the customer's premise, whether supplied by public potable water or an auxiliary water supply. The system or systems may be a potable water system, an irrigation system, a fire protection system, or an industrial piping system. This is a single meter system with a single service line (no main lines).

Public water system: The potable water system owned and operated by Salisbury-Rowan Utilities. This system includes all distribution mains, lines, pipes, connections, storage tanks, and other facilities conveying potable water from the water treatment plant(s) to the service connections of each customer.

Reduced pressure principle assembly: A backflow prevention assembly containing within its structure a minimum of two (2), independently acting, approved check valves, together with an automatically operating pressure relief 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 shall be less than the supply pressure. In case of leakage of either check valve, the differential relief valve, by discharge to atmosphere, shall operate to maintain the pressure between the checks tightly closing shut-off valves located at each end of the device. Each device shall be fitted with properly located test cocks. This assembly is designed to protect against a severe/imminent hazard.

Salisbury-Rowan Utilities (SRU): A department of the City of Salisbury responsible for the operation and maintenance of the water and wastewater systems owned and/or operated by the City of Salisbury.

Service connection: The terminal end of a water connection from the public potable water system, i.e., where the water purveyor looses jurisdiction and sanitary control over the water at its point of delivery (individual or master meter) to the consumer's water system.

Used water: 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.

Water purveyor: Owner or operator of a public potable water system providing an approved water supply to the public.

Water supply-auxiliary: Any water supply on or available to the customer's premises other than the purveyor'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, etc., and used or objectionable water and constitute an unacceptable water source over which the water purveyor does not have sanitary control.

Water supply-unapproved: Any water supply, which has not been approved for human consumption by the North Carolina Department of Environment and Natural Resources (DENR).

(Ord. No. 2007-11, § 1, 4-3-07)