These guidelines are supplemental to Section .1006(b) of the "Rules Governing Public Water Supplies". These guidelines are intended as a minimum requirement. Public water suppliers may adopt more stringent requirements. Each supplier of water shall conform to the minimum requirements established in these guidelines.
I. Degree of Hazard:
A. Severe: Actual or potential threat of contamination that presents an imminent danger to the public health with consequence of serious illness or death.
B. Moderate: One that presents foreseeable and significant potential for pollution, nuisance, aesthetically objectionable or other undesirable alterations of the drinking water supply.
II. Backflow Prevention Assembly Requirements:
Degree of Hazard | RPZ* | DCVA** | Air Gap |
Severe | X | ------- | X |
Moderate | ------ | X | ------- |
III. Facilities that require installation of a Backflow Preventer***:
A. Moderate Hazard - DCVA:
1. Fire sprinkler systems without booster pump facilities or chemical additives.
2. Connection to tanks, lines and vessels that handle non-toxic substances.
3. Lawn sprinkler systems without chemical injection or booster pumps.
4. Most commercial establishments
5. Automotive service stations, bakeries and beauty shops with no health hazard and bottling plants with no back pressure.
6. Etc.
* Reduced Pressure Zone
** Double Check Valve Assembly
*** This is not intended to be an exhaustive list.
B. Severe Hazard - RPZ or Air Gap
1. Lawn sprinkler systems with chemical injection or booster pump.
2. Wastewater Treatment Plants
3. Connection to an unapproved water system or unapproved auxiliary water supply.
4. Connection to tanks, pumps, lines, steam boilers and vessels that handles sewage, lethal substances, toxic or radioactive substances.
5. Fire sprinkler systems with booster pump facilities or chemical additives.
6. Buildings with five or more stories above ground.
7. Hospitals and other medical facilities.
8. Morgues, mortuaries and autopsy facilities.
9. Metal plating facilities.
10. Bottling plants (subject to back pressure).
11. Canneries.
12. Battery manufacturers.
13. Exterminators and lawn care companies.
14. Chemical processing plants.
15. Dairies.
16. Film Laboratories.
17. Car Wash Facilities.
18. Dye Works.
19. Laundries.
20. Swimming Pools.
21. Water front facilities.
22. Etc.
IV. Approved Backflow Prevention Assemblies:
Meets American Society of Sanitary Engineering (ASSE) standard and carries ASSE Seal or is on the University of Southern California approval list.
V. Backflow Prevention Assembly Installation:
Backflow prevention assemblies must be located in a place where it is readily accessible for regular testing, maintenance and inspection. Bypass lines parallel to a backflow prevention assembly shall have an approved backflow prevention assembly installed that is equal to that on the main line.
(Ord. passed 4-2-2001)