Surface Water Supply Index Report

The SWSI is designed for areas that rely primarily on snowmelt runoff as the primary source of surface water. The SWSI accounts for snowpack, mountain precipitation, streamflow, reservoir contents, and soil moisture conditions. The SWSI can be used by irrigators, fisheries personnel, recreationists, and others who utilize surface waters. SWSI values are categorized as follows:

ID	Basin Name	Value
1	Marias Above Tiber Reservoir	-0.4
1	Marias Above Tiber Reservoir	-0.4
2	Tobacco	-0.3
2	Tobacco	-0.3
3	Kootenai to Libby Dam	0.5
3	Kootenai to Libby Dam	0.5
4	Kootenai River below Libby Dam	0.3
4	Kootenai River below Libby Dam	0.3
5	Fisher River	-0.5
5	Fisher River	-0.5
6	Yaak River	-0.7
6	Yaak River	-0.7
7	North FK. Flathead River	-0.8
7	North FK. Flathead River	-0.8
8	Middle FK. Flathead River	-1.1
8	Middle FK. Flathead River	-1.1
9	South FK. Flathead River	-0.9
9	South FK. Flathead River	-0.9
10	Flathead at Columbia Falls	-0.9
10	Flathead at Columbia Falls	-0.9
11	Stillwater/Whitefish Rivers	0.5
11	Stillwater/Whitefish Rivers	0.5
12	Swan River	-1
12	Swan River	-1
13	Flathead River at Polson	-0.8
13	Flathead River at Polson	-0.8
14	Mission Valley	1.6
14	Mission Valley	1.6
15	Little Bitterroot River	3.4
15	Little Bitterroot River	3.4
16	Clark above Missoula	2.2
16	Clark above Missoula	2.2
17	Blackfoot River	-0.6
17	Blackfoot River	-0.6
18	Clark Fork above Missoula	0.7
18	Clark Fork above Missoula	0.7
19	Bitterroot River	1.2
19	Bitterroot River	1.2
20	Clark Fork River below Bitterroot River	0.8
20	Clark Fork River below Bitterroot River	0.8
21	Clark Fork River below Flathead River	-0.3
21	Clark Fork River below Flathead River	-0.3
22	Beaverhead River	2.8
22	Beaverhead River	2.8
23	Ruby River	1.8
23	Ruby River	1.8
24	Big Hole River	0.6
24	Big Hole River	0.6
25	Boulder River (Jefferson)	0.8
25	Boulder River (Jefferson)	0.8
26	Jefferson River	1.9
26	Jefferson River	1.9
27	Madison River	1.2
27	Madison River	1.2
28	Gallatin River	1.3
28	Gallatin River	1.3
29	Missouri River above Canyon Ferry	1.4
29	Missouri River above Canyon Ferry	1.4
30	Missouri River below Canyon Ferry	1.5
30	Missouri River below Canyon Ferry	1.5
31	Smith River	2.3
31	Smith River	2.3
32	Sun River	1.4
32	Sun River	1.4
33	Teton River	1.9
33	Teton River	1.9
34	Birch/Dupuyer	-0.3
34	Birch/Dupuyer	-0.3
36	Musselshell River	2.8
36	Musselshell River	2.8
37	Missouri River above Fort Peck	3
37	Missouri River above Fort Peck	3
38	Missouri River below Fort Peck	1
38	Missouri River below Fort Peck	1
39	Milk River	-0.2
39	Milk River	-0.2
41	Yellowstone River above Livingston	0.6
41	Yellowstone River above Livingston	0.6
42	Shields River	-1
42	Shields River	-1
43	Boulder River (Yellowstone)	0.3
43	Boulder River (Yellowstone)	0.3
44	Stillwater River	0.6
44	Stillwater River	0.6
45	Rock/Red Lodge Creeks	2
45	Rock/Red Lodge Creeks	2
46	Clarks Fork River	0.3
46	Clarks Fork River	0.3
47	Yellowstone River above Bighorn River	-0.4
47	Yellowstone River above Bighorn River	-0.4
48	Bighorn River below Bighorn Lake	1.6
48	Bighorn River below Bighorn Lake	1.6
49	Little Bighorn River	-0.6
49	Little Bighorn River	-0.6
50	Yellowstone River below Bighorn River	1.3
50	Yellowstone River below Bighorn River	1.3
51	Tongue River	-1.2
51	Tongue River	-1.2
52	Powder River	0.3
52	Powder River	0.3
999	Kootenai at Ft. Steele	-1.2
999	Kootenai at Ft. Steele	-1.2

August 1998
Surface Water Supply Index Report

Provided by the US Natural Resources Conservation Service
Bozeman, Montana

August 1998 Surface Water Supply Index Report

Provided by the US Natural Resources Conservation Service Bozeman, Montana

August 1998
Surface Water Supply Index Report

Provided by the US Natural Resources Conservation Service
Bozeman, Montana