PDFWAC 372-36-030
Domestic sewage rules.
(1) Municipal and community. (Including school and industrial installations):
(a) The discharge of raw sewage is prohibited under any circumstances.
(b) The discharge of sewage treatment plant effluent into canals used for irrigation or stock watering is prohibited.
(c) The discharge of sewage treatment plant effluent into drains, wasteways, or reservoirs, from which water is subsequently reused in canals and laterals is prohibited, except by specific approval where special circumstances may require such discharge.
(d) The disposal of sewage treatment plant effluent by land application methods is prohibited in locations where such disposal would adversely affect surface or groundwater withdrawn for domestic purposes. Discharge at extreme depths is prohibited.
(Note: | Rules and regulations of the state board of health prohibit irrigation of certain crops with sewage plant effluent.) |
(e) The minimum degree of treatment shall, in any case, be at least the equivalent of primary treatment and disinfection of the effluent.
(f) Additional treatment, of a degree to be determined for each case, shall be provided where specific approval is granted for discharge to drains, wasteways, or reservoirs.
(g) Additional treatment, of a degree to be determined for each case, shall be provided prior to disposal by land application methods when necessary to prevent possible contamination of ground and surface waters, or creation of a nuisance.
(h) Notwithstanding (a) through (g) of this subsection, the degree of treatment, the provision for disinfection and method of disposal shall be a matter for the determination and approval of the department of ecology for each individual case.
(2) Individual farm unit, household or other source of domestic sewage not covered by subsection (1) of this section.
(a) No raw sewage or septic tank effluent shall be discharged to any canal, reservoir, drain or wasteway.
(b) Households, farm units, schools, small business concerns or other sources of domestic sewage involving a limited number of persons shall provide sewage disposal facilities as prescribed by the county health department of the county in which the source is located.
[Statutory Authority: RCW 43.216.001 [43.21B.001] and chapter 43.21A RCW. WSR 88-13-029 (Order 88-62), ยง 372-36-030, filed 6/8/88; Rule .04.242, filed 3/1/60.]