§ 50.198 BACKFLOW PREVENTION METHODS.
   Unless otherwise specifically designated by the Director:
   (A)   Approved backflow prevention method. An approved backflow prevention method shall be one of the following types:
      (1)   Air gap. An unobstructed vertical distance through the free atmosphere between the opening of any pipe or faucet, supplying potable water to a tank plumbing fixture or other device and the flood level rim of the tank, plumbing fixture or other device. An approved air gap shall be at least double the diameter of the supply pipe or faucet and in no case less than one inch.
      (2)   Reduced pressure principle assemble (hereafter RP). 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 assembly shall include properly located test cocks equipped with properly located test cocks fitted with brass plugs and tightly closing resilient seated shutoff valves located at each end of the assembly.
      (3)   Pressure vacuum breaker assembly (hereafter PVB). An assembly containing an independently operating loaded check valve and an independently operating, loaded air inlet valve located on the discharge side of the check valve. The assembly shall be equipped with properly located test cocks fitted with brass plugs and tightly closing resilient seated shutoff valves located at each end of the assembly.
      (4)   Double check valve assembly (hereafter DC). An assembly composed of two independently acting, approved check valves, including tightly closing resilient seated shutoff valve at each end of the assembly and fitted with properly located test cocks equipped with brass plugs.
   (B)   Requirements for new services and existing services. An approved backflow prevention method is required for the activities or facilities listed in this section that are connected to the public water system. The backflow prevention method shall be in accordance with that specified in § 7 of the USC-CCCHR Manual. The location shall be as close as practicable to the point of service delivery except that the customer may request that the approved backflow prevention method be located internally within the activity or facility. The customer must demonstrate that the proposed location will adequately protect the public water supply as well as satisfy the applicable requirements of this chapter. For purposes of this section, the listed facilities, equipment or conditions shall be as defined in § 7 of the USC-CCCHR Manual, or if not listed in the USC-CCCHR Manual, shall be defined in the Town of Florence Design Standards and Policies Manual.
      (1)   Industrial facilities.
         (a)   Beverage bottling plants (air gap, RP or DC);
         (b)   Breweries (air gap or RP);
         (c)   Canneries, packing houses, reduction plants and food processing plants (air gap or RP);
         (d)   Dairies and cold storage plants (air gap, RP or DC);
         (e)   Film laboratories (air gap or RP);
         (f)   Laundry and dye works (air gap or RP);
         (g)   Metal manufacturing, cleaning, processing and fabricating plants (air gap, RP or DC);
         (h)   Oil and gas production, storage or transmission properties (air gap or RP);
         (i)   Paper and paper products plants (air gap or RP);
         (j)   Plating plants (air gap or RP);
         (k)   Sand and gravel plants (air gap or RP);
         (l)   Semiconductor manufacturing facilities (air gap or RP); and
         (m)   Sewage and storm drain facilities, reclaimed water (air gap or RP).
      (2)   Medical facilities.
         (a)   Research laboratories (air gap or RP);
         (b)   Hospitals, medical buildings, sanitariums, morgues, mortuaries, autopsy facilities, nursing and convalescent homes and clinics (air gap or RP); and
         (c)   Veterinary hospital, animal research or animal grooming shops (air gap or RP).
      (3)   Commercial and educational facilities.
         (a)   Any structure having a cross connection in violation of the Town of Florence Plumbing Code or water operated sewage pumping facilities, auxiliary water supplies or other like sources of contamination which would create a potential hazard to the public water system (air gap, RP or DC);
         (b)   Carwash facilities (air gap or RP);
         (c)   Multi-storied buildings having booster pumps or above-ground storage tanks (air gap, RP or DC);
            1.   Multiple services; interconnected (air gap RP or DC);
            2.   Exception: Existing facilities which are not otherwise listed in this section.
         (d)   1.   Mobile home parks (RP or DC);
            2.   Exception: Existing mobile home parks unless a specific hazard is identified.
         (e)   Recreation vehicle parks (RP or DC);
         (f)   Schools and colleges with laboratories (air gap or RP); and
            1.   Retail shopping centers and strip mails; retail and industrial shell buildings (when one service supplies more than one tenant) (RP).
            2.   Exception: Existing retail shopping center and strip malls retail and industrial shell buildings (when one service supplies more than one tenant) unless a specific hazard is identified.
      (4)   Portable or temporary services or equipment.
         (a)   Construction sites or construction water services (air gap or RP);
         (b)   Mobile equipment, utilizing public potable water (i.e. water trucks, street sweepers, hydrovacs and the like) (air gap or RP); and
         (c)   Portable insecticide and herbicide spray tanks (air gap or RP).
      (5)   Miscellaneous activities and equipment.
         (a)   Auxiliary water systems (Air gap or RP);
         (b)   Chemically contaminated water system (Air gap or RP);
         (c)   Fire systems.
            1.   Class 1 or 2. No backflow prevention assembly required. Check valve assemblies required by the Town of Florence Fire Chief shall be inspected, tested and maintained at least annually to verify the valves are properly installed and functioning. Annual flow and valve confidence tests shall be performed by a certified tester to test and maintain fire lines or fire sprinkler systems. Test results, on forms approved by the town, shall be provided to the Director and the town Fire Chief within 30 days following the inspection. Any fire sprinkler system which fails shall be repaired as required by the Fire Code.
            2.   Class 3, 4, 5 or 6 (RP).
         (d)   Industrial fluid systems. Any industrial fluid system interconnected with the public water supply and containing any fluid or solution which may be chemically, biologically or otherwise contaminated or polluted in a form or concentration such as would constitute a health system, pollution or plumbing hazard into an approved water supply (RP or DC).
         (e)   Irrigation systems.
            1.   System using a chemical injection system (RP);
            2.   System having elevated areas which are higher than six inches below the PVB or multiple services (RP); and
            3.   System not subject to back pressure (PVB).
         (f)   Restricted, classified or other closed facilities, including civil works. (Air gap or RP).
            1.   Solar heating systems; direct and auxiliary. (RP).
            2.   Exception: Once through solar heating systems.
      (6)   The Public Works Director shall determine on a case-by-case basis backflow prevention requirements for any facility or activity not listed in this section in order to prevent contamination or pollution of the public potable water system.
      (7)   All assemblies shall be accessible for testing and maintenance. A reduced pressure principle assembly or double check valve assembly shall not be installed in a basement, meter box, pit or vault unless adequate clearance and drainage is provided. A pressure vacuum breaker assembly shall be installed above ground.
      (8)   Unless a cross connection problem is specifically identified, or as otherwise provide in this chapter, the requirements of this chapter do not apply to a single-family residences used solely for residential purposes.
      (9)   Close as practicable is the point nearest the service delivery where the assembly can be installed. Where the assembly installation location may interfere with obstacles such as driveways and sidewalks, then close as practicable in the nearest point after the obstacle, but in no event beyond the first tap.
      (10)   An air gap separation shall be located as close as practicable to the customer's point of service delivery. All piping between the customer's connection and receiving tank shall be entirely visible unless otherwise approved by the Director.
(Prior Code, Ch. 18, Art. II, § 18-132) (Ord. 346-04, passed 6-21-2004)