Island Pk Reservoir
Fremont County, IdahoView mapDirections
Idaho DEQ publishes the water-quality measurements for Island Pk Reservoir. Here is what has been measured.
- Eutrophic
- Limited data
Island Pk Reservoir in Fremont County, Idaho has water-quality measurements published by Idaho DEQ, shown here as reported. Water clarity: 2.3 ft visibility. Phosphorus: 56 µg/L. Chlorophyll-a (algae): 9.8 µg/L.
Island Pk Reservoir is a productive, nutrient-rich eutrophic lake in Fremont County, Idaho. Overall water quality is improving over recent sampling years. Compared to the 2 other monitored lakes in Fremont County, Island Pk Reservoir ranks #2 for water quality.
Source: EPA Water Quality Portal sampling records, IDEQ, last sampled 2024-05-21. Methodology: how these readings are compared.
What Island Pk Reservoir is good for
From access and monitoring records, not editorial picks.
- Camping1 public campground nearby
Swimming conditions
Readings onlyLimited data
Based on clarity and algae readings from past sampling — there is no live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.
Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Whether Island Pk Reservoir is safe to swim in today is a call for the Idaho Department of Environmental Quality and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Island Pk Reservoir
These are the measurements Idaho DEQ publishes for Island Pk Reservoir, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Very murky, less than 2.3 ft of visibility. Phosphorus 56 µg/L. Chlorophyll-a 9.8 µg/L. TSI 60.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 2.3ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 56µg/L | Poor GoodFairPoor |
| Chlorophyll-a (algae) | 9.8µg/L | Poor GoodFairPoor |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 60 | Eutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
High nutrients, frequent algae, reduced clarity
Ask about Island Pk Reservoir
Answers come straight from the public measurements and survey records on this page.
Recreation & Access
Public campgrounds near Island Pk Reservoir
- Box Canyon Campground1.4 km
Nearest public campgrounds in the USGS National Map inventory, within about 3 miles. An empty list means USGS records no campground that close, which is not the same as camping being unavailable. Where the source gives an official reservation link, it is used; the cabin and hotel search does not cover campsites. More camping lakes
Stays via Stay22
Stays near Island Pk Reservoir
Compare lakeside cabins, hotels, and vacation rentals near Island Pk Reservoir in Fremont County, Idaho — live availability and prices for your trip. Switch the map to Satellite to see the lake and how close each stay is to the water. The water-quality readings cover nutrients and algae, not lodging. Cabins and rentals around Island Pk Reservoir are listed below.
Top-rated places to stay near Island Pk Reservoir
Prices for Oct 30–Nov 1, 4 adults. Change dates on the map below.
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Fishing Island Pk Reservoir
Water Quality Trend: Improving
Based on 4 years of monitoring (2012–2019).
Water clarity
Improving3 years
Phosphorus
Improving-3.25 µg/L/yr4 years
Chlorophyll-a
Improving-1.85 µg/L/yr4 years
Nearby Lakes in Fremont County
Frequently asked questions about Island Pk Reservoir
Where is Island Pk Reservoir?
- Island Pk Reservoir is a lake in Fremont County, Idaho. Its water-quality measurements are published by Idaho DEQ and shown on this page as reported.
What is the water quality of Island Pk Reservoir?
- Island Pk Reservoir in Fremont County, Idaho has water-quality measurements published by Idaho DEQ, shown here as reported. Water clarity: 2.3 ft visibility. Phosphorus: 56 µg/L. Chlorophyll-a (algae): 9.8 µg/L.
Is Island Pk Reservoir safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Are there campgrounds on Island Pk Reservoir?
- Island Pk Reservoir has 1 public campground from USGS The National Map within 5 km, including Box Canyon Campground. This is a location join, not a booking. Cabins and hotels are listed separately; campsite reservations use the official link when the source provides one.
Explore Island Pk Reservoir across LakeQuality
2 documented falls within 14.6 mi, nearest Upper Mesa Falls
2 thermal springs within 20.7 mi, nearest Ashton Warm Spring
Species activity outlook by water temperature and season
Where to stay at Idaho's top lakes, each with its readings
Idaho's cleanest lakes, ranked on agency measurements
More lakes in Idaho
Other Lakes in Idaho
Eutrophic Lakes in Idaho
Where this data comes from
26 measurements from 1 monitoring station, 2012–2024. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Bureau of Reclamation
1119USBR_WQX26 samples · 2012–2024
Analytical methods
- Depth, Secchi disk depth
- Zebra/Quagga Mussel APHA 10200G Modified
- Phosphorus by Single Reagent Colorimetry
- 10200 H ~ Chlorophyll a-b-c Determination
- Turbidity by Nephelometry
Monitoring station identifiers (1)
EPA condition classes from the National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See where the data comes from and data sources.
Other records on this page
Public campgrounds from USGS The National Map Structures, within about 3 miles