IdahoReservoirFremont County

Island Park Reservoir

Island Park Reservoir is a 3,958-acre reservoir in Idaho. You will find it in Fremont County. It is managed by USDA Forest Service (Caribou-Targhee NF; USBR-owned).

Photo: James N Perdue · Public domain · Wikimedia Commons

CountiesFremont County

Coordinates44.4244, -111.3711

Surface area3,958 acres

Managed byUSDA Forest Service (Caribou-Targhee NF; USBR-owned)

Swimming beaches on Island Park Reservoir

No named swimming beach is mapped yet for this lake. Access is through agency day-use areas and boat ramps listed below. We add beach pages only when we can confirm a name, coordinates and an operating agency.

Island Park Reservoir on the map

Lake center, swimming spots and access points.

Get directions

Weather and water temperature

Air temperature and wind from Open-Meteo. Water temperature only when the lake has a public sensor.

Weather data by Open-Meteo

Island Park Reservoir at a glance

Its coordinates are 44.4244, -111.3711. Surface elevation is about 6,293 feet.

No public gauge reports the water level at Island Park Reservoir, so this page shows no level chart. We would rather leave the figure out than publish an estimate that nobody measured. For a lake this size, the park office is the fastest way to learn how the water sits today.

Old Faithful Inn, on Yellowstone Lake, is the closest named beach in this guide, about 27 miles off. Shoreline access on lakes like this one is often informal and unsigned. Island Park Reservoir has no catalogued swimming beach in the sources we read, so plan around the managing agency's own facilities.

Nearby water includes Henrys Lake (Idaho, 15 mi), Hebgen Lake (Montana, 30 mi) and Yellowstone Lake (Wyoming, 50 mi). In all, 26 lakes in Idaho are covered here.

Water temperature is not measured at this lake by any public agency we read. Most Idaho day-use areas open for the summer season and close outside it. Freshwater advisories are issued locally, so check the state health department before you swim.