Washington Administrative Code › Title 173 - Ecology, Department of (See also Titles 197, 317, 372, and 508) › Chapter 173-549 - Water resources program in the Okanogan River basin, WRIA-49 › Section 173-549-020 - Establishment of minimum instream flows

Current through Register Vol. 24-14, July 15, 2024
(1) Minimum instream flows are established
			 for stream management units with monitoring to take place at certain control
			 points as follows:
Stream Management Unit Information
Stream Management
Unit Name, Control
Station Name and
Number
Control Station
Location by River
Mile, Section,
Township, Range
Affected Stream
Reach
Lower Okanogan
Okanogan R.
at Malott
(12447200)
17.0,
9-32-25E
Okanogan River
confluence with
Wells Pool to confluence of Chewiliken Cr.
Middle Okanogan
Okanogan R.
nr. Tonasket
(12445000)
50.8,
8-36-27E
Okanogan River confluence of Chewiliken Creek to
							 confluence Similkameen River
Upper Okanogan
Okanogan R.
at Oroville
(12439500)
77.3,
27-40-27E
Okanogan River confluence of Similkameen River to
							 Osoyoos Lake
Similkameen
Similkameen R.
at Nighthawk
(12442500)
15.8,
7-40-26E
Similkameen River confluence with Okanogan River to
							 Canadian Border
(2)
			 Minimum instream flows established for the stream management units in WAC
			 173-549-020(1) are as follows:
Minimum Instream Flows in the Okanogan River
(All Figures in Cubic Feet Per Second)
Month
Day
Lower
Okanogan
12447200
Middle
Okanogan
1244500
Upper
Okanogan
124426000
Similkameen
12439500
Jan.
1
860
800
320
400
15
830
800
320
400
Feb.
1
820
800
320
400
15
850
800
320
400
Mar.
1
880
800
320
425
15
900
800
320
450
Apr.
1
925
910
330
510
15
1,100
1,070
340
640
May
1
1,750
1,200
350
1,100
15
3,800
3,800
500
3,400
Jun.
1
3,800
3,800
500
3,400
15
3,800
3,800
500
3,400
Jul.
1
2,100
2,150
420
1,900
15
1,200
1,200
350
1,070
Aug.
1
800
840
320
690
15
600
600
300
440
Sept.
1
620
600
300
400
15
700
600
300
400
Oct.
1
750
730
330
450
15
960
900
370
500
Nov.
1
950
900
370
500
15
950
900
320
500
Dec.
1
930
900
320
500
15
900
850
320
450
(3)
			 Minimum instream flow hydrographs, as represented in WAC
			 173-549-900, shall be used for
			 definition of minimum instream flows on those days not specifically identified
			 in WAC 173-549-020(2).
(4) Future consumptive water right permits
			 hereafter issued for diversion of surface water from the mainstem Okanogan
			 River and the Similkameen River shall be expressly subject to minimum instream
			 flows established in WAC
			 173-549-020(1) through
			 (3)    except those described in WAC
			 173-549-070.
(5) Projects that would reduce the flow in a
			 portion of a stream's length (e.g. hydroelectric projects that bypass a portion
			 of a stream) will be considered consumptive only with respect to the affected
			 portion of the stream. Such projects will be subject to instream flows as
			 specified by the department. These flows may be those established in WAC
			 173-549-020 or, when appropriate,
			 may be flows specifically tailored to that particular project and stream reach.
			 When studies are required to determine such reach- and project-specific flow
			 requirements, the department may require the project proponent to conduct such
			 studies.
Statutory Authority:
				  Chapters
				  90.54 and 90.22 RCW.
				  84-13-076 (Order DE 84-15), § 173-549-020, filed 6/20/84; Order DE 76-25,
				  § 173-549-020, filed 7/14/76.