13.20.040 - Definitions.
Except where the context otherwise requires, the definitions that are provided in this section govern the construction of this chapter; provided, however, if any of such definitions conflict with the definition of the corresponding word or term in any federal or state law or regulation, the definition that is contained in such law or regulation shall prevail.
Approved:
1. "Approved" as herein used in reference to a water supply means a water supply that has been approved by the health agency having jurisdiction.
2. "Approved" as herein used in reference to an air-gap, a double check valve assembly, a reduced pressure principle backflow prevention assembly or other backflow prevention assemblies or methods means an approval by the city of North Las Vegas.
"Auxiliary water supply" means any water supply on or available to the premises other than the city of North Las Vegas' approved public water supply will be considered as an auxiliary water supply. These auxiliary waters may include water from another purveyor's public potable water supply or any natural source(s) such as a well, spring, river, lake, etc., or used waters or industrial fluids. These waters may be contaminated or polluted or they may be objectionable and constitute an unacceptable water source over which the city does not have sanitary control.
"Backflow" means the undesirable reversal of the flow of water or the mixture of water and other liquids, gases or other substances into the distribution pipes of the potable supply of water from any source or sources. See also terms "backpressure" and "backsiphonage."
"Backflow preventer" means an assembly or means designed to prevent backflow.
1. "Air gap" means 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" shall be at least double the diameter of the supply pipe measured vertically above the overflow rim of the vessel, but in no case, less than one inch (2.54 cm).
2. "Reduced pressure principle backflow prevention assembly" means an assembly containing 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 unit shall include properly located resilient seated test cocks and tightly closing resilient seated shutoff valves at each end of the assembly. This assembly is designed to protect against a nonhealth (i.e., pollutant) or a health hazard (i.e., contaminant). This assembly shall not be used for backflow protection of sewage or reclaimed water.
3. "Double check valve backflow prevention assembly" means an assembly composed of two independently acting, approved check valves, including tightly closing resilient seated shutoff valves attached at each end of the assembly and fitted with properly located resilient seated test cocks. This assembly shall only be used to protect against a nonhealth hazard (i.e., pollutant).
"Backpressure" means any elevation of pressure in the downstream piping system (by pump, elevation of piping, or steam and/or air pressure) above the supply pressure at the point of consideration which would cause, or tend to cause, a reversal of the normal direction of flow.
"Backsiphonage" means a form of backflow due to a reduction in the system pressure which causes a subatomospheric pressure to exist at a site in the water system.
"Contamination" means an impairment of the quality of the water which creates an actual hazard to the public health through poisoning or through the spread of disease by sewage, industrial fluids, waste, etc.
"Cross-connection" means any unprotected actual or potential connection or structural 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 fluid, gas, or substance 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.
1. "Direct cross-connection" means a cross-connection which is subject to both backsiphonage and backpressure.
2. "Indirect cross-connection" means a cross-connection which is subject to backsiphonage only.
"Cross-Connection Control by Contaminant." The term "service protection" means the appropriate type or method of backflow protection at the service connection, commensurate with the degree of hazard of the consumer's potable water system.
Cross-Connections, Controlled. "Controlled cross-connections" means a connection between a potable water system and a nonpotable 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.
Hazard, Degree of. "Degree of hazard" means either a pollutional (nonhealth) or contamination (health) hazard and is derived from the evaluation of conditions within a system.
1. "Health hazard" means an actual or potential threat of contamination of a physical or toxic nature to the public potable water system or the consumer's potable water system that would be a danger to health.
2. "Plumbing hazard" means an internal or plumbing type cross-connection in a consumer's potable water system that may be either a pollutional or a contamination type hazard. This includes but is not limited to cross-connections to toilets, sinks, wash trays and lawn sprinkling systems. Plumbing type cross-connections can be located in many types of structures including homes, apartment houses, hotels and commercial or industrial establishments. Such a connection, if permitted to exist, must be properly protected by an appropriate type of backflow prevention assembly.
3. "Pollutional hazard" means an actual or potential threat to the physical properties of the water system or the potability of the public or consumer's potable water system but which would not constitute a health or 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.
4. "System hazard" means an actual or potential threat of severe danger to the physical properties of the public or the consumers potable water system or of a pollution or contamination which would have a protracted effect on the quality of the potable water in the system.
"Industrial fluids" means any fluid or solution which may be chemically, biologically or otherwise contaminated or polluted in a form or concentration which would constitute a health, system, pollutional or plumbing hazard if introduced into an approved water supply. This may include, but not be limited to, polluted or contaminated used waters; all types of process waters and "used waters" originating from the public potable water system which may deteriorate in sanitary quality; chemicals in fluid form; plating acids and alkalies, circulated cooling waters connected to an open cooling tower and/or cooling waters that are chemically or biologically treated or stabilized with toxic substances; contaminated natural waters such as from wells, springs, streams, rivers, lakes, irrigation canals or systems, etc.; oils, gases, glycerine, paraffins, caustic and acid solutions and other liquid and gaseous fluids used industrially, for other processes, or for fire fighting purposes.
"Pollution" means an impairment of the quality of the water to a degree which does not create a hazard to the public health but which does adversely and unreasonably affect the aesthetic qualities of such waters for domestic use.
Water, Nonpotable. "Nonpotable water" means a water supply which has not been approved for human consumption by the health agency having jurisdiction.
Water, Potable. "Potable water" means any public potable water supply which has been investigated and approved by the health agency having jurisdiction. The system must be operating under a valid health permit. In determining what constitutes an approved water supply, the health agency has final judgment as to its safety and potability.
Water, Service Connection. "Service connection" means the terminal end of a service connection from the public potable water system (i.e., where the city may lose jurisdiction and sanitary control of the water at its point of delivery to the consumer's water system). If a water meter is installed at the end of the service connection, then the service connection shall mean the downstream end of the water meter.
Water, Used. "Used water" means any water supplied by a water purveyor from a public potable water system to a consumer's water system after it has passed through the service connection and is no longer under the control of the water purveyor.
(Ord. 1125 § 2 (part), 1994: prior code § 4.17.020)
