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	SWSI
1	Marias River above Tiber Reservoir	0.899999976158142
2	Tobacco River	1.5
3	Kootenai Ft. Steele to Libby Dam	2
4	Kootenai River below Libby Dam	1.70000004768372
5	Fisher River	1.29999995231628
6	Yaak River	0.600000023841858
7	North Fk. Flathead River	2
8	Middle Fk. Flathead River	2.09999990463257
9	South Fk. Flathead River	3
10	Flathead River at Columbia Falls	2.29999995231628
11	Stillwater/Whitefish
12	Swan River	2.79999995231628
13	Flathead River at Polson	2.5
14	Mission Valley	4
15	Little Bitterroot River
16	Clark Fork River above Milltown	2.79999995231628
17	Blackfoot River	3.29999995231628
18	Clark Fork River above Missoula	3.20000004768372
19	Bitterroot River	1.79999995231628
20	Clark Fork River below Bitterroot River	2.70000004768372
21	Clark Fork River below Flathead River	2.59999990463257
22	Beaverhead River	1.10000002384186
23	Ruby River	1.5
24	Big Hole River	1.5
25	Boulder River (Jefferson)	2.79999995231628
26	Jefferson River	1.89999997615814
27	Madison River	1.29999995231628
28	Gallatin River	1.5
29	Missouri River above Canyon Ferry	1.79999995231628
30	Missouri River below Canyon Ferry	0.899999976158142
31	Smith River	2.70000004768372
32	Sun River	2
33	Teton River	1.20000004768372
34	Birch/Dupuyer Creeks	0.600000023841858
35	Marias River below Tiber Reservoir	2.5
36	Musselshell River	1.60000002384186
37	Missouri River above Fort Peck	0.699999988079071
38	Missouri River below Fort Peck	1.79999995231628
39	Milk River
40	Dearborn River near Craig
41	Yellowstone River above Livingston	3.20000004768372
42	Shields River	3.40000009536743
43	Boulder River (Yellowstone)	2.59999990463257
44	Stillwater River	3
45	Rock/Red Lodge Creeks	-0.100000001490116
46	Clarks Fork River	3.70000004768372
47	Yellowstone River above Bighorn River	3.20000004768372
48	Bighorn River below Bighorn Lake	2.70000004768372
49	Little Bighorn River
50	Yellowstone River below Bighorn River	2.59999990463257
51	Tongue River	-0.600000023841858
52	Powder River	1.5
53	Upper Judith Basin
54	St. Mary River	2

April 2018
Surface Water Supply Index Report

Provided by the US Natural Resources Conservation Service
Bozeman, Montana

April 2018 Surface Water Supply Index Report

Provided by the US Natural Resources Conservation Service Bozeman, Montana

April 2018
Surface Water Supply Index Report

Provided by the US Natural Resources Conservation Service
Bozeman, Montana