[R.O. 2009 §13.20.010; Ord. No. 4417 §1, 1983; Ord. No. 5202 §2, 5-4-1998]
As used in this Chapter, the following terms shall have these prescribed meanings:
- AIR-GAP SEPARATION
- The unobstructed vertical distance through the free atmosphere between the lowest opening from any pipe or faucet supplying water to a tank, plumbing fixture or other device and the flood level rim of the receptacle and shall be at least double the diameter of the supply line pipe measured vertically above the flood level rim of the vessel. In no case shall the gap be less than one (1) inch.
- AUXILIARY SUPPLY
- Any water source of system, other than the public water supply, that may be available in the building or premises or which is not a water supply approved by the Missouri Division of Health.
- The undesirable reversal of flow of water or mixtures of water and other liquids, gases or other substances into the public water supply from any source(s).
- BACKFLOW PREVENTION DEVICE
- A device to counteract back pressures or prevent back siphonage.
- BACK PRESSURE
- Backflow caused by a pump, elevated tank, boiler or other means that could create pressure within the system greater than the public water supply pressure.
- BACK SIPHONAGE
- A form of backflow due to a negative or sub-atmospheric pressure within a water system.
- CERTIFIED BACKFLOW PREVENTION ASSEMBLY TESTER
- A person who has proven his/her competency to test, repair, overhaul and make reports on backflow prevention assemblies to the satisfaction of the Missouri Department of Natural Resources.
- Any physical arrangement whereby a public water supply is connected directly or indirectly with any other water supply system, sewer, drain, conduit, pool, storage reservoir, plumbing fixture or other device which contains or may contain contaminated water, sewage or other waste or liquid of unknown or unsafe quality which may be capable of imparting contamination to the public water supply as a result of backflow. By-pass arrangements, jumper connections, removable section, swivel or changeover devices and other temporary or permanent devices through which, or because of which, a backflow can, or may occur are considered to be cross-connections.
- DOUBLE CHECK VALVE ASSEMBLY
- An assembly composed of two (2) single, independently acting check valves, including tightly closing shutoff valves located at each end of the assembly and suitable connections for the in-line testing of the water-tightness of each check valve.
- PUBLIC WATER SUPPLY
- Any system of water supply intended or used for human consumption or other domestic uses, including source, treatment, storage, transmission and distribution facilities where water is furnished to any community, collection or number of individuals or is made available to the public for human consumption or domestic use, but excluding water supplied serving one (1) single-family residence.
- REDUCED PRESSURE PRINCIPAL BACKFLOW PREVENTION DEVICE
- A device containing two (2) independently acting, internally loaded, approved check valves together with a hydraulically operating, mechanically independent pressure relief valve located between the check valves. The device shall include tightly closing shutoff valves at each end of the assembly and shall be equipped with necessary appurtenances for in-line testing. The pressure differential relief valve shall operate to maintain the pressure in the zone between the two (2) check valves at least two (2) pounds per square inch less than the public water supply pressure. At cessation of normal flow, the pressure between the check valves shall be less than the supply pressure. In case of leakage of either check valve, the differential pressure relief valve shall operate to maintain this reduced pressure by discharging to the atmosphere. When the inlet pressure is two (2) pounds per square inch or less, the relief valve shall open to the atmosphere thereby providing an air-gap in the device.
- THE DEPARTMENT
- The Missouri Department of Natural Resources.
- THE UTILITY
- The Board of Municipal Utilities.
[R.O. 2009 §13.20.020; Ord. No. 4417 §2, 1983; Ord. No. 5202 §2, 5-4-1998]
The purpose of this Chapter is to establish a cross-connection control program to protect the health of water consumers by the control of actual and/or potential cross-connections through the proper installation and surveillance of backflow prevention devices on service lines leading to premises where cross-connections exist or are likely to occur and through the inspection and regulation of the plumbing within the premises to minimize danger of contamination of the water system on the premises or the public water supply itself. The cross-connection control program will comply with the provisions of the Missouri Code of State Regulations, Title 10 CSR 60-11, Backflow Prevention.
[R.O. 2009 §13.20.030; Ord. No. 4417 §3, 1983; Ord. No. 5202 §2, 5-4-1998]
All cross-connections, whether or not such cross-connections are controlled by automatic devices such as check valves or by hand-operated mechanisms such as gate valves or stop cocks, are hereby prohibited.
[R.O. 2009 §13.20.040; Ord. No. 4417 §4, 1983; Ord. No. 5202 §2, 5-4-1998]
Failure on the part of persons, firms or corporations to discontinue the use of any and all cross-connections and to physically separate such cross-connections will be sufficient cause for the discontinuance of the public water service to the premises on which the cross-connection exists.
[R.O. 2009 §13.20.050; Ord. No. 4417 §5, 1983; Ord. No. 5202 §2, 5-4-1998]
The utility shall make periodic inspections of premises served by the public water supply to check for the presence of cross-connections. Should such a cross-connection be found, the utility, giving the customer not less than fifteen (15) days' notice of its intention, will discontinue service. If an immediate hazard to health is caused by the cross-connection, water service to the premises shall be disconnected and discontinued until it is verified that the cross-connection has been removed.
[R.O. 2009 §13.20.060; Ord. No. 4417 §§6—11, 1983; Ord. No. 5202 §2, 5-4-1998]
Backflow prevention devices shall be installed at the service connection within any premises where in the judgment of the utility the nature and extent of activities on the premises or the materials used in connection with the activities or materials stored on the premises would present an immediate hazard to health should a cross-connection occur, even though such cross-connection does not exist at the time the backflow prevention device is required to be installed. This shall include, but not be limited to, the following situations:
Premises having an auxiliary water supply, unless the quality of the auxiliary water supply is in compliance with local standards and is acceptable to the utility;
Premises having internal cross-connections that are not correctable or intricate plumbing arrangements which make it impractical to ascertain whether or not cross-connections exist;
Premises where entry is restricted so that inspections for cross-connections cannot be made with sufficient frequency or at sufficiently short notice to assure that cross-connections do not exist;
Premises having a repeated history of cross-connections being established or re-established;
Premises on which any substance is handled under pressure so as to permit entry into the public water supply or where a cross-connection could reasonably be expected to occur. This shall include the handling of process waters and cooling waters;
Premises where materials of a toxic or hazardous nature are handled such that if back siphonage should occur, a serious health hazard may result;
The following types of facilities will fall into one (1) of the above categories where a backflow prevention device is required to protect the public water supply. A backflow prevention device shall be installed at these facilities unless the utility determines no hazard exists:
Hospitals, mortuaries, clinics, medical buildings;
Sewage treatment plants;
Food or beverage processing plants;
Chemical plants using a water process;
Metal plating industries;
Petroleum processing or storage plants;
Radioactive material processing plants or nuclear reactors;
Commercial laundries and dye works;
Paper processing plants;
Auxiliary water systems;
Fire protection systems;
Sprinkler systems filled with anti-freeze solution;
Film processing equipment;
Storage tanks, cooling towers and circulating systems;
Steam generating systems; and
The type of protective device required shall be determined by the utility and shall depend on the degree of hazard which exists. Backflow hazards may be classified as Class I (contamination) or Class II (objectionable substances). Protection devices required for each class are further defined as follows:
Class I backflow hazards (contamination). An air-gap separation or a reduced pressure principle backflow prevention device shall be installed where the water supply may be contaminated with sewage, industrial waste of a toxic nature or other contaminant which would cause an immediate or potential health or system hazard.
Class II backflow hazards (objectionable substances). In a case of a substance which may be objectionable but not hazardous to health, a double check valve assembly, air-gap separation or a reduced pressure principle backflow prevention device shall be installed.
Backflow prevention devices shall be installed on the customer water system immediately inside the wall where the customer service line enters the premise or at a location designated by the utility.
Reduced pressure principal backflow prevention devices shall be installed with no plug or additional piping affixed to the pressure differential relief valve port (except for specifically designed funnel apparatus available from the manufacturer) and with the pressure differential relief port a minimum of twelve (12) inches above floor or ground level. Additionally, the assembly shall be installed at a location where any leakage from the pressure differential relief valve port will be noticed, that allows easy access to the assembly for maintenance and testing and that will not subject the assembly to flooding, excessive heat or freezing.
Double check valve backflow prevention devices shall be installed at a location that allows easy access to the assembly for maintenance and testing and that will not subject the assembly to excessive heat or freezing.
No by-pass piping shall be allowed around a backflow prevention assembly unless the by-pass is equipped with an identical backflow prevention assembly.
Backflow prevention devices shall be installed at the customer's expense.
[R.O. 2009 §13.20.070; Ord. No. 4417 §12, 1983; Ord. No. 5202 §2, 5-4-1998]
Any protective device required in this Chapter shall be a model approved by the utility and the department.
[R.O. 2009 §13.20.080; Ord. No. 4417 §13, 1983; Ord. No. 5202 §2, 5-4-1998]
Backflow prevention devices shall be inspected and tested annually or more often where successive inspections indicate repeated failure. The devices shall be inspected and tested at the customer's expense and repaired or replaced and retested at the customer's expense whenever they are found to be defective. The devices shall also be overhauled by the customer at intervals recommended by the device manufacturer. All such inspections, tests, repairs and overhauls shall be conducted by a certified backflow prevention assembly tester. The original copy of certified test results shall be forwarded to the utility within thirty (30) days after making the inspection or test or repairs or overhaul and retesting.
[R.O. 2009 §13.20.090; Ord. No. 4417 §14, 1983]
Failure of the customer to cooperate in the installation, maintenance, testing or inspection of backflow prevention devices required in this Chapter shall be grounds for the termination of water services to the premises.