Alexander Reservoir
Caribou County, Idaho1,007 acresView mapDirections
No nutrient or algae sampling on record from Idaho DEQ for this lake.
- Impaired · Nutrients (phosphorus, nitrogen)
Alexander Reservoir in Caribou County, Idaho has water-quality measurements published by Idaho DEQ, shown here as reported. Surface area: 1007 acres.
Alexander Reservoir is a 1,007-acre lake in Caribou County, Idaho.
Source: EPA Water Quality Portal sampling records, IDEQ. Methodology: how these readings are compared.
What Alexander Reservoir is good for
From access and monitoring records, not editorial picks.
- Big water1,007 acres
Swimming conditions
No readingNot rated
Nutrient and algae readings are not a swimming clearance. Alexander Reservoir is listed impaired under Clean Water Act §303(d) (IR 4A) for nutrients (phosphorus, nitrogen), turbidity. Check local advisories before you swim.
Whether Alexander 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 Alexander Reservoir
These are the measurements Idaho DEQ publishes for Alexander Reservoir, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
No clarity data. TSI undefined.
Ask about Alexander Reservoir
Answers come straight from the public measurements and survey records on this page.
Lake Details
Surface area
1,007 acres
Shoreline
15.2 mi
No bathymetric survey has been published for Alexander Reservoir, so its depth is not documented here.
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Stays near Alexander Reservoir
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Fishing Alexander Reservoir
EPA Impairment Status
Alexander Reservoir is officially listed as impaired under Clean Water Act §303(d) in the 2022 EPA reporting cycle (IR category 4A).
Causes of impairment
Designated uses not supporting: Aquatic life.
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit ID16010201BR001_0L · Official waterbody report
Nearby Lakes in Caribou County
Frequently asked questions about Alexander Reservoir
Where is Alexander Reservoir?
- Alexander Reservoir is a lake in Caribou County, Idaho. Its water-quality measurements are published by Idaho DEQ and shown on this page as reported.
What is the water quality of Alexander Reservoir?
- Alexander Reservoir in Caribou County, Idaho has water-quality measurements published by Idaho DEQ, shown here as reported. Surface area: 1007 acres.
Is Alexander Reservoir safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Alexander Reservoir is listed impaired under Clean Water Act §303(d) (IR 4A) for nutrients (phosphorus, nitrogen), turbidity. Check local advisories before you swim.
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Where this data comes from
Measurements for Alexander Reservoir come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.
Other records on this page
Impairment status from EPA ATTAINS 303(d) database