Cal. Code Regs. tit. 22 § 64575

Current through Register 2024 Notice Reg. No. 49, December 6, 2024

Section 64575 - Flushing

(a) A flushing valve or blowoff shall be provided at the end of each newly installed dead-end water main. Fire hydrants meeting the criteria of this section may be considered flushing valves.

(b) Flushing valves and blowoffs shall not discharge to a sanitary sewer without an air gap separation between the sewer and the valve or blowoff.

(c) The flushing velocity in the main shall not be less than 2.5 ft/s unless it is determined that conditions do not permit the required flow to be discharged to waste.

(d) Newly installed flushing valves and blowoffs shall be designed to maintain the minimum continuous flushing flows as indicated below to produce a minimum velocity of 2.5ft/s in commonly used sizes of pipe.

Table 64575-A. Minimum Flushing Flows for Different Size Water Mains.

	*Nominal Main Size Diameter (inches)*	*Minimum Flushing Flow (gallons per minute)*
	2	25
	3	50
	4	100
	6	225
	8	400
	10	600
	12	900
	14	1200
	16	1600

Cal. Code Regs. Tit. 22, § 64575

1. New section filed 2-8-2008; operative 3-9-2008 (Register 2008, No. 6).
2. Change without regulatory effect amending subsection (a) filed 4-21-2011 pursuant to section 100, title 1, California Code of Regulations (Register 2011, No. 16).

Note: Authority cited: Sections 116350, 116375 and 131200, Health and Safety Code. Reference: Sections 116275, 116375, 116535 and 131051, Health and Safety Code.