§ 34-575. Circulation system.

(a)

Design and operation. A separate circulation system is required for each pool and shall consist of pump(s), piping, filter(s), water conditioning and disinfection equipment, and other accessory equipment that will clarify, condition, and disinfect the water in accordance with this article. All pool equipment shall meet the standards set forth in the most recent edition of ANSI/NSF-50, "Circulation System Components and Related Materials for Swimming Pools, Spas/Hot Tubs", or other approved, independent testing and certifying organization. The equipment shall be operated continuously on a 24-hour basis to obtain the minimum required number of four turnovers per day, or one turnover every six hours. All pool piping systems shall be designed to accommodate 100 percent of the design flow rate. During normal pool operation, a maximum of 20 percent of the circulation flow shall be through the main drain and a minimum of 80 percent shall be through the overflow gutters or skimmers. All circulation system components, including filter(s), pump(s), hair lint strainer(s) and other similar components, shall function properly and be maintained in a clean condition. For circulation systems utilizing gutter-type circulation, an approved surge device shall be provided. Timers used in conjunction with any circulation equipment are prohibited whenever the pool is open for use, but may be used when the pool is not open during the off season.

(1)

Pumps. Pump(s) shall be adequate in number and capacity to provide the required pool turnover rate. Pumps shall supply the design circulation and backwash flows at a dynamic head sufficient to overcome friction losses in the piping, appurtenances and maximum filter head loss. If more than one pump is utilized in design or construction, then all of the pumps shall be the same including manufacturer, size, capacity, and other similar factors. Pump performance curves shall be submitted with the plans. An adequately sized strainer shall be provided on the suction side of the circulation pump. Secondary pumps, if used on vacuum filter systems, shall be protected by a strainer sized to adequately protect the pump. Strainers shall be inspected as often as necessary and maintained in a clean condition.

(2)

Filters. Filter(s) shall be sized and maintained to accommodate the required design circulation flow. If more than one filter is utilized in design or construction, then all of the filters shall be the same including manufacturer, size, capacity, and other similar factors.

(3)

Inlets. Adjustable inlets installed flush with the pool wall or floor shall be located in conjunction with the proposed method of circulation so as to provide effective, uniform circulation of the incoming water throughout the pool and to prevent stagnant areas. The total number of inlets shall be calculated based on one inlet for every 20 linear feet of pool perimeter or major fraction thereof. Inlets shall be evenly spaced either along the pool perimeter or on the pool floor. Inlets shall be installed below the normal water level. Floor inlets shall be provided on all pools with surface areas exceeding 2,000 square feet. Additional inlets may be used or may be required in addition to the minimum required number of floor inlets for steps, seats, and sun shelf areas to facilitate circulation. Wall inlet fittings shall not project more than 1½ inches from the surface of the pool wall.

(4)

Suction outlets and fittings. Each pool shall be provided with two or more hydraulically balanced main drain openings for each main drain line at the deepest portion of the pool and constructed to completely drain the pool. Main drain openings must be covered by an approved, secured grating, removed only by a tool and not removable by bathers. All covers or grates for suction outlets of main drains shall conform to the latest edition of ANSI/ASME 112.19.8, "Suction Fittings for Use in Swimming Pools, Wading Pools, Spas, Hot Tubs and Whirlpool Bathtub Appliances", and installed according to manufacturer's specifications. The open area of each drain cover shall be at least four times the cross-sectional area of the drain pipe, and sufficient flow area shall be provided so that the full flow velocity at any part of the grate will not exceed 1½ feet per second. Openings between grate bars shall not exceed one-half inch. Main drain openings shall be constructed in parallel, in a tee configuration, and spaced evenly across the deep area of the pool, with a minimum spacing of six feet between each main drain opening. Each pool shall be provided with a hydrostatic relief valve with a minimum size of two inches or a more extensive hydrostatic system if necessary. A minimum of two hydrostatic relief valves are required on pools with surface areas in excess of 1,800 square feet.

(5)

Skimmers and overflow gutters. A surface skimming or gutter system shall be provided for each pool and shall be designed and constructed to skim the pool surface when the water level is maintained within the operating water level range of the system's weir device or rim.

(6)

Vacuum cleaning system. A vacuum system shall be provided for pool cleaning. The vacuum fitting shall be easily accessible through an opening on the deck that is securely covered when not in use. Wall-mounted type vacuum systems are not approved. If approved for use, portable vacuum systems shall not be stored on the pool deck.

(7)

Flow meters. An adequately sized flow meter, capable of measuring and indicating a minimum range of one-half to 1½ times the design flow rate shall be installed on the pool return line to accurately indicate the circulation rate in gallons per minute. Flow meters shall be conspicuously located and installed in accordance with the manufacturer's instructions for placement.

(8)

Heaters. Pools equipped with heaters shall have a fixed thermometer in the circulation line. Water temperature shall be thermostatically controlled. Adequate external valves and piping shall be provided to enable bypassing the heater and to facilitate complete removal for repairs without interruption of pool circulation. At all times the temperature in the pool water shall not exceed 104 degrees Fahrenheit. Heaters shall be installed according to the manufacturer's instructions and in accordance with all applicable state, county and local codes. An unbreakable thermometer designed for use in a pool must be available for bathers and pool staff to monitor pool water temperatures. Control of the pool's water temperature shall not be accessible to bathers.

(Ord. No. 09-0120, 1-7-09; Ord. No. 18-0340, Att. A, 5-16-18)