Current through Register Vol. 60, No. 12, December 1, 2021
pH (hydrogen ion concentration). pH
values may not fall outside the following ranges:
(a) Hood River Basin streams (except main
stem Columbia River and Cascade lakes): pH values may not fall outside the
range of 6.5 to 8.5;
lakes above 3,000 feet altitude: pH values may not fall outside the range of
6.0 to 8.5.
Dissolved Solids. Guide concentrations listed below may not be exceeded unless
otherwise specifically authorized by DEQ upon such conditions as it may deem
necessary to carry out the general intent of this plan and to protect the
beneficial uses set forth in OAR
Criteria for Treatment and Control of Sewage Wastes in this Basin:
(a) During periods of low stream flows
(approximately May 1 to October 31): Hood River Basin streams (except main stem
Columbia River): Treatment resulting in monthly average effluent concentrations
not to exceed 10 mg/l of BOD and 10 mg/l of suspended solids or equivalent
(b) During the period of
high stream flows (approximately November 1 to April 30): A minimum of
secondary treatment or equivalent control and unless otherwise specifically
authorized by the Department, operation of all waste treatment and control
facilities at maximum practicable efficiency and effectiveness so as to
minimize waste discharges to public waters.
Or. Admin. R.
DEQ 17-2003, f. & cert.
Stat. Auth.: ORS 468.020, 468B.030, 468B.035 &
Stats. Implemented: ORS 468B.030, 468B.035 &