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Crystal Lake

NR
Not yet rated
Hypereutrophic
Limited DataHypereutrophic

Crystal Lake in Rice County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Phosphorus: 241 µg/L. Chlorophyll-a (algae): 75.8 µg/L.

Public access
No
Ice-out
Mar 16

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Why Crystal Lake has no grade

We grade a lake only when its monitoring record clears the evidence bar: at least three phosphorus or chlorophyll-a samples in the last ten years, scored against EPA National Lakes Assessment thresholds for this lake’s ecoregion. For Crystal Lake, no nutrient or algae measurement meets the evidence bar (at least 3 samples within 10 years). Sampling here has recorded phosphorus and algae (chlorophyll-a), but not water clarity.

Not Rated is not an F. It is EPA Integrated Reporting Category 3 — insufficient information. The water here may be excellent or poor; nobody has measured enough of it to say. Everything below that has been measured is still reported on this page.

Sampling is run by MPCA and volunteer programs, and published through the EPA Water Quality Portal. Read the full grading methodology.

Crystal Lake is a lake in Rice County, Minnesota. Limited fish-species data available. No public access — the lake is private or restricted.

Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-09-17. Grade methodology: LakeGrade methodology.

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Swimming Safety

Not rated

Limited data

Not rated for swimming — there is not enough monitoring data to judge this lake

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Water quality measurements for Crystal Lake

These readings exist but do not meet the evidence bar for an A–F grade — see why.

No clarity data. Phosphorus level: 241 µg/L. Chlorophyll-a: 75.8 µg/L. Trophic State Index: 78.

MetricValueGrade
Water Clarity (Secchi Depth)No recent samples
Phosphorus241 µg/LNot graded
Chlorophyll-a (Algae)75.8 µg/LNot graded
Trophic State Index (TSI)78Hypereutrophic

Very high nutrients, dense algae, poor clarity

Where to stay near Crystal Lake

Compare lakeside cabins, hotels, and vacation rentals near Crystal Lake in Rice County, Minnesota — 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.

Top-rated places to stay near Crystal Lake

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Fishing Crystal Lake

Ice Season

Historical ice data from Minnesota DNR (3 observations).

Typical Ice-Out
Mar 16
EarliestLatest
Ice-Out2024-02-26 (2024)2022-04-08 (2022)

Most recent ice-out: 2024-02-26

Regulated Pollution Sources Nearby

2 EPA-permitted facilities operate within about 5 miles of Crystal Lake under Clean Water Act (NPDES) discharge permits, including 1 classified by the EPA as major discharger. 2 facilities have a reported Clean Water Act violation in the past three years.

  • Faribault Wwtp
    Faribault · 3 mi away · NPDES MN0030121
    MajorRecent violation
  • Faribault Foods - Faribault Division
    Faribault · 3.2 mi away · NPDES MN0050491
    Recent violation

Facilities permitted to discharge under the Clean Water Act within ~5 miles; proximity does not by itself mean a facility affects this lake. Source: EPA ECHO (ICIS-NPDES), as of 2026-07.

Graded lakes near Crystal Lake

Crystal Lake has no grade, but these lakes within a short drive do.

Nearby Lakes in Rice County

Frequently asked questions about Crystal Lake

What is the water quality grade for Crystal Lake?

Crystal Lake in Rice County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Phosphorus: 241 µg/L. Chlorophyll-a (algae): 75.8 µg/L.

Is Crystal Lake safe to swim in?

Not rated for swimming — there is not enough monitoring data to judge this lake. Crystal Lake is not rated for water quality — its monitoring record does not meet the evidence bar. Algae concentration (chlorophyll-a) is 75.8 µg/L. Always check local health department advisories before swimming.

When does Crystal Lake thaw?

Crystal Lake typically has ice-out around Mar 16.

Where this data comes from

2 measurements from 1 monitoring station, 2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.

Collected and reported by

  • Minnesota Pollution Control Agency - Ambient Surface WaterMNPCA2 samples · 2025

Analytical methods

  • Phosphorus by Colorimetry
  • 10200 H ~ Chlorophyll a-b-c Determination
Monitoring station identifiers (1)

Grade thresholds from the EPA National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See how grades are calculated and data sources.

Other records on this page

Regulated discharger data from EPA ECHO (ICIS-NPDES)

Ice data from Minnesota DNR Climate