What is the water quality grade for Cascade Reservoir?

Cascade Reservoir in Valley County, Idaho received a water quality grade of B (Good). Water clarity: 8.2 ft visibility. Phosphorus: 31 µg/L. Chlorophyll-a (algae): 1.1 µg/L.

Is Cascade Reservoir safe to swim in?

Good for swimming, clear water with low algae levels. Cascade Reservoir has an overall water quality grade of B. Algae concentration (chlorophyll-a) is 1.1 µg/L. Always check local health department advisories before swimming.

Valley County, Idaho

Cascade Reservoir

Grade BGood · 8.2 ft clarity

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Mesotrophic

Cascade Reservoir is a mesotrophic lake in Valley County, Idaho. Water quality is graded B based on 3 sampling years through 2024. Compared to the 14 other monitored lakes in Valley County, Cascade Reservoir ranks #8 for water quality.

Source: EPA Water Quality Portal sampling records, Idaho DNR, last sampled 2024-09-16. Grade methodology: LakeGrade methodology.

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Swimming Safety

Good for swimming, clear water with low algae levels

Water Quality Grade: B, Good

Moderate clarity, visible to about 8.2 ft. Phosphorus level: 31 µg/L. Chlorophyll-a: 1.1 µg/L. Trophic State Index: 44.

Metric	Value	Grade
Water Clarity (Secchi Depth)	8.2 ft	C
Phosphorus	31 µg/L	C
Chlorophyll-a (Algae)	1.1 µg/L	A
Trophic State Index (TSI)	44	Mesotrophic

Moderate nutrients, good water quality

Where to stay near Cascade Reservoir

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