Statutes, codes, and regulations
Virginia Administrative Code
Title 12 - HEALTHAgency 5 - DEPARTMENT OF HEALTHChapter 610 - SEWAGE HANDLING AND DISPOSAL REGULATIONSPart V - Design and Construction Criteria
Article 4 - Conveyance Systems
Section 12VAC5-610-890 - Siphons

12 Va. Admin. Code § 5-610-890

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Current through Register Vol. 40, No. 22, June 17, 2024
Section 12VAC5-610-890 - Siphons
A. Use. Intermittent dosing siphons have two major uses:
1. Low pressure dosing of subsurface soil absorption systems (see 12VAC5-610-940 ); or
2. To provide more uniform distribution of effluent to large or multiple sectioned subsurface soil absorption systems which split the flow 12 or more times or contain 1200 linear feet or more of percolation piping (see 12VAC5-610-930 A and B).
B. Materials. Materials for construction of dosing siphon chambers are the same as for septic tanks (see 12VAC5-610-810 ).
C. Number and sizing. Dosing siphons discharging to subsurface soil absorption systems shall have an average discharge rate greater than 2.5 times the average daily influent flow in gallons per minute but not less than 70 gallons per minute per 1200 linear feet of percolation lines. Twin alternating siphons are required where the system to be dosed exceeds 1800 linear feet in accordance with 12VAC5-610-930 B. The volume of the dosing chamber shall equal 0.6 the volume of the percolation piping for enhanced flow distribution. Actual dosing chamber volume is determined on a case-by-case basis where low pressure distribution is utilized (see 12VAC5-610-940 A).
D. Access. The siphon chamber shall terminate at or above the ground surface. The top of the chamber shall be removable to an extent to allow access for maintenance, repairs and removal of the siphon components.
E. Construction. Dosing chambers constructed of precast or poured in place concrete shall conform with the construction requirements contained in 12VAC5-610-815 E.
F. Force mains. Force mains used in conjunction with siphons shall meet the applicable criteria contained in 12VAC5-610-880 A.

12 Va. Admin. Code § 5-610-890

Derived from VR355-34-02 § 4.24, eff. February 5, 1986; amended, eff. May 11, 1988; Virginia Register Volume 16, Issue 16, eff. July 1, 2000. Subsurface Soil Absorption System

Statutory Authority

§§ 32.1-12 and 32.1-164 of the Code of Virginia.