Riordan Lake
Valley County, Idaho74 acresView mapDirections
No nutrient or algae sampling on record from Idaho DEQ for this lake.
Riordan Lake in Valley County, Idaho has water-quality measurements published by Idaho DEQ, shown here as reported. Surface area: 74 acres.
Riordan Lake is a 74-acre lake in Valley County, Idaho.
Source: EPA Water Quality Portal sampling records, IDEQ. Methodology: how these readings are compared.
Swimming conditions
No readingNot rated
Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Whether Riordan Lake 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 Riordan Lake
These are the measurements Idaho DEQ publishes for Riordan Lake, 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 Riordan Lake
Answers come straight from the public measurements and survey records on this page.
Lake Details
Surface area
74 acres
Shoreline
1.9 mi
No bathymetric survey has been published for Riordan Lake, so its depth is not documented here.
Stays via Stay22
Stays near Riordan Lake
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Fishing Riordan Lake
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Frequently asked questions about Riordan Lake
Where is Riordan Lake?
- Riordan Lake is a lake in Valley County, Idaho. Its water-quality measurements are published by Idaho DEQ and shown on this page as reported.
What is the water quality of Riordan Lake?
- Riordan Lake in Valley County, Idaho has water-quality measurements published by Idaho DEQ, shown here as reported. Surface area: 74 acres.
Is Riordan Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
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Where this data comes from
Measurements for Riordan Lake come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.