The lake bed in 3-D: deep basin, drop-offs and shoreline. Shape estimated, not for navigation. Spot 1 (upper arm) is open for everyone; the other 6 come with LakeScope PRO. Full screen
Island Park Reservoir
Fremont County, Idaho · about 7,180 acres (11.2 sq mi)
42°F water, calm this morning.
About Island Park Reservoir
Island Park Reservoir is a reservoir in Fremont County, Idaho, covering about 7,180 acres. It was made by Island Park Dam on the Henrys Fork (Snake River). Island Park Reservoir is formed by a dam on the Henrys Fork of the Snake River near Yellowstone.
It stretches about 10.6 miles end to end and its shoreline adds up to about 51 miles. Its surface is about 6,300 ft above sea level. West Yellowstone lies about 20 miles to the northeast. The closest city is Idaho Falls, about 67 miles away.
- Size
- About 7,180 acres (11.2 sq mi)
- Shoreline
- About 51 miles
- End to end
- About 10.6 miles
- Elevation
- About 6,300 ft
- Type
- Reservoir
- Dam
- Island Park Dam, Henrys Fork (Snake River)
- County
- Fremont County
The lake from above
Best fishing times
Saturday Good
- 6:45 am – 9:00 amsunrise · wind 1 mph
- 3:30 pm – 5:30 pm bestsunset, moon overhead · wind 6 mph
Sunday Good
- 6:45 am – 9:00 amsunrise · wind 1 mph
- 4:30 pm – 5:30 pm bestsunset, moon overhead · wind 8 mph
Based on sun and moon times and the wind forecast. A guide, not a promise. The app shows the whole week.
Fish to expect
Expect the usual Idaho mix for a lake this size: trout, yellow perch and smallmouth bass. The state fish and wildlife agency lists what is stocked and the rules for this lake. At 42°F on the surface right now, here is how each one should behave.
- GoodTrout
Good range. Near the surface and along shorelines.
- GoodYellow perch
Schooled near weed edges and soft bottom.
- SlowSmallmouth bass
Cold. Slow presentations on deep rock.
From today's water temperature and the season. A guide, not a promise.
Fishing spots
- 1Upper arm
The lake narrows toward the incoming river or creek; moving water carries food.
- 2
- 3
- 4
- 5
- 6
- 7
6 more spots with LakeScope PRO: fish, depth band, water temperature, best time and bait for each.
Picked from the shape of the lake bed. A guide, not a promise.
Water temperature
At the surface, seen .
Water level
No daily level reading for this lake.
Ice
Open water
Ice thickness is an estimate from air temperature, not a measurement. Check the ice yourself before going on it.
Weather and wind
Sunrise 7:19 am · sunset 5:00 pm · waxing crescent moon (lake time).
Towns and places to stay near Island Park Reservoir
- West Yellowstoneabout 20 mi northeast
- Ashtonabout 21 mi south
- Saint Anthonyabout 29 mi south
- Idaho Fallsnearest city, about 67 mi southwest
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Questions about Island Park Reservoir
What fish are in Island Park Reservoir?
Lakes like Island Park Reservoir usually hold trout, yellow perch and smallmouth bass. Check the state fish and wildlife agency for stocking and limits.
How deep is Island Park Reservoir?
We have no published depth for this lake. The 3-D view gives an estimated shape of the bed: where the deep basin and the drop-offs are. Not for navigation.
How big is Island Park Reservoir?
About 7,180 acres, with about 51 miles of shoreline.
What town is near Island Park Reservoir?
West Yellowstone is about 20 miles northeast; Ashton is about 21 miles south.
What is the water temperature at Island Park Reservoir today?
The surface was about 42°F on the latest clear reading. The page updates every day.
Island Park Reservoir on your phone
The whole week of bite times, lake alerts and the 3-D view, every morning.
