§ 16.15.140. Circulation and filtration.

A.

A pool shall have a complete circulation system, including pumping equipment, filters, balancing tanks, valves, pipe connections to the inlets and outlets of the pool, and provisions for cleaning the filters.

B.

At least four turnovers of the pool water are required every 24 hours.

C.

Skimmers may be approved under 16.15.080.

D.

Hair and lint catchers shall be used in pressure filter systems and shall be:

1.

Corrosion-resistant, with openings to provide a free flow area at least four times the area of the pump suction line; and

2.

Readily accessible for frequent cleaning.

E.

The piping system of a pool shall be built to prevent:

(1)

Wastewater from entering the circulation system of the pool; and

(2)

Water from the circulation system from entering the make-up water supply.

F.

Water velocity in pipes may not exceed six feet per second.

G.

Balancing tanks are required on all filter systems. For pools built or extensively remodeled after December 23, 1993, the capacity, in gallons, shall be 15 times the maximum bathing load. Vacuum filter systems may use a combination surge/filter tank.

H.

The size of the circulation pump is determined from total dynamic head including maximum head loss through the filter, and from velocities required for backwashing.

I.

The department may waive circulation system requirements for flowthrough pools if:

1.

The water supply provides at least four turnovers of the pool water every 24 hours;

2.

The water supply meets the requirements of 18 AAC 70.020 for contact recreation and section 16.15.190, and is disinfected as set out in section 16.15.150;

3.

Fresh treated water is introduced into the pool by the same type of inlet design required by subsection 16.15.120 A.; and

4.

Drain outlets meet the requirements of subsection 16.15.120 C.

J.

Filters shall completely drain by gravity.

K.

If diatomaceous earth filters are used, disposal of the used diatomaceous earth shall be approved by the department.

L.

Cartridge filters may be allowed, if a waiver of provisions is granted under section 16.15.080.

M.

Sand filters shall be physically inspected by the operator at least once each year for channeling, buildup, compaction, or other flow resistance factors. Filter media shall be replaced, if channeling, buildup, compaction, or any other flow resistance factor is observed. All inspection dates and results shall be noted by the operator on the pool log.

(AO No. 99-11, § 6, 2-9-99)