Francis Lake
Isanti County, Minnesota269 acresView mapDirections
Minnesota PCA publishes the water-quality measurements for Francis Lake. Here is what has been measured.
- Hypereutrophic
- Impaired · Impaired biota (cause unknown)
- 7 ft max depth
- Public access
- Limited data
Francis Lake in Isanti County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 2 ft visibility. Phosphorus: 159 µg/L. Chlorophyll-a (algae): 56.1 µg/L. Maximum depth: 7 ft. Surface area: 269.43 acres.
Minnesota DNR's Targeted Survey on June 19, 2024 caught 33.49 largemouth bass per hour of electrofishing at Francis Lake. Length samples in the latest survey that recorded them ran 0–0 inches. DNR survey details →
Francis Lake is a 269-acre highly nutrient-loaded hypereutrophic lake in Isanti County, Minnesota with a maximum depth of 7 feet (4-foot average). Overall water quality is improving over recent sampling years. The lake supports 14 documented fish species including black bullhead, black crappie, and bluegill. Public access is available with 1 public boat landing. Compared to the 16 other monitored lakes in Isanti County, Francis Lake ranks #15 for water quality.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2024-10-05. Methodology: how these readings are compared.
What Francis Lake is good for
From access and monitoring records, not editorial picks.
- Boat launch1 documented ramp
- Fishing14 species recorded
- Ice seasonIce-out around Apr 11
Swimming conditions
Readings onlyRecreation use not supported
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. Francis Lake is listed impaired under Clean Water Act §303(d) (IR 5) for impaired biota (cause unknown), nutrients (phosphorus, nitrogen). Check local advisories before you swim.
Whether Francis Lake is safe to swim in today is a call for the Minnesota Pollution Control Agency and the Minnesota DNR and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Francis Lake
These are the measurements Minnesota PCA publishes for Francis Lake, 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 ft of visibility. Phosphorus 159 µg/L. Chlorophyll-a 56.1 µg/L. TSI 71.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 2ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 159µg/L | Poor GoodFairPoor |
| Chlorophyll-a (algae) | 56.1µg/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. | 71 | Hypereutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Very high nutrients, dense algae, poor clarity
Ask about Francis Lake
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Francis Lake typically sits around 74°F at the surface in August. Summer average is about 74°F. Usually warmest in Jul (about 76°F) and coldest in Jun (about 72°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (72°F) to its warmest (76°F).
Typical surface water temperature by month, from 11 field readings (2018–2024) via the EPA Water Quality Portal. See the full Francis Lake water temperature breakdown →
Minnesota DNR's Targeted Survey on June 19, 2024 caught 33.49 largemouth bass per hour of electrofishing at Francis Lake. Length samples in the latest survey that recorded them ran 0–0 inches.
A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Francis Lake’s water-quality measurements separately, and the water-quality trend over 2 years of monitoring is improving. Catch rate is not a swim clearance and is not a weekly bite report.
DNR Fisheries Survey Summary
6 surveys on file from MN DNR Fisheries. Most recent: 2024-06-19 (Targeted Survey).
6 surveys on file · most recent 2024-06-19 (Targeted Survey)
| Species | Catch rate (CPUE) | Size | Avg weight |
|---|---|---|---|
| Yellow Perch | 96.82 | 5–11 in 2024-06-03 | 0.15 lb |
| Black Bullhead | 59.72 | 8–13 in 2024-06-03 | 0.24 lb |
| Black Crappie | 35.48 | 3–11 in 2024-06-03 | 0.27 lb |
| Largemouth Bass | 9.81 | 0 in 2024-06-19 | 1.65 lb |
| Bluegill | 8.11 | 4–9 in 2024-06-03 | 0.27 lb |
CPUE = catch per unit effort, fish caught per net per set in a standardised survey. It measures abundance, not size, and is not a weekly bite report.
Length Distributions
Number of fish caught at each inch class in the most recent survey that recorded lengths. Red dashed line marks an approximate trophy threshold for that species.
Yellow Perch
Black Bullhead
Black Crappie
Largemouth Bass
From the 2024-06-19 survey
A survey of nearshore fish species was conducted on Francis Lake on June 19, 2024 by Hinckley fisheries staff. Ten sampling sites were evenly spaced around the shoreline and each site was sampled by electrofishing, and/or seining. Nearshore sampling captured 17 species of fish: Bluegill, Black Crappie, Largemouth…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Francis Lake. 4 reports on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — FrancisFisheries Lake Survey · MN DNR LakeFinder
- —Aquatic Plant Report — Francis (1848)Aquatic Plant Report · MN DNR LakeFinder
- —Fish Stocking History — FrancisFish Stocking History · MN DNR LakeFinder
- —Public Water Access Sites — FrancisPublic Water Access Sites · MN DNR LakeFinder
Lake Details
Max depth
7 ft
Average depth
4 ft
Surface area
269 acres
Shoreline
3.8 mi
Littoral zone
100%
Share shallower than 15 ft
Public access
Yes
Listed by Minnesota PCA
Lake Size & Watershed
Watershed (drainage) area
3 sq mi
HydroLAKES / HydroSHEDS
Elevation
906 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Recreation & Access
- Francis LakePublic
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Stays via Stay22
Stays near Francis Lake
Compare lakeside cabins, hotels, and vacation rentals near Francis Lake in Isanti 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. The water-quality readings cover nutrients and algae, not lodging. Cabins and rentals around Francis Lake are listed below.
Top-rated places to stay near Francis Lake
Prices for Oct 9–11, 4 adults. Change dates on the map below.
Availability and prices from Stay22 partners (Booking.com, Vrbo, Expedia). We may earn a commission from bookings, at no extra cost to you.
Planning a whole trip? See where to stay at Minnesota’s top lakes →
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Fish Species
Click a species to see every lake where it is documented.
Fishing Francis Lake
Water quality readings over time
2 seasons of samples on record (2021–2024). Calling a direction takes at least 4 years of the same measurement.
Water clarity
Improving2 years
Ice season
Typical ice-out
Apr 11
Earliest Mar 3, 2024 · Latest May 5, 2013
Typical ice-in
Nov 16
Earliest Nov 7, 2006 · Latest Nov 24, 2007
Most recent ice-out
Mar 31
2026
22 observations · Minnesota PCA ice records
EPA Impairment Status
Francis Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 5).
Causes of impairment
Designated uses not supporting: Aquatic life, Recreation.
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit MN30-0080-00 · Official waterbody report
Nearby Lakes in Isanti County
Frequently asked questions about Francis Lake
Where is Francis Lake?
- Francis Lake is a lake in Isanti County, Minnesota. Its water-quality measurements are published by Minnesota PCA and shown on this page as reported.
What is the water quality of Francis Lake?
- Francis Lake in Isanti County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 2 ft visibility. Phosphorus: 159 µg/L. Chlorophyll-a (algae): 56.1 µg/L. Maximum depth: 7 ft. Surface area: 269.43 acres.
Is Francis Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Francis Lake is listed impaired under Clean Water Act §303(d) (IR 5) for impaired biota (cause unknown), nutrients (phosphorus, nitrogen). Check local advisories before you swim.
What is the water temperature of Francis Lake?
- Francis Lake typically sits around 74°F at the surface in August, from 11 EPA Water Quality Portal field readings (2018–2024). That is a typical value for the month, not a live reading.
How deep is Francis Lake?
- Francis Lake has a maximum depth of 7 feet and an average depth of 4 feet. The lake covers 269.43 acres.
What fish are in Francis Lake?
- Fish species found in Francis Lake include black bullhead, black crappie, bluegill, bowfin (dogfish), brown bullhead, common carp, green sunfish, hybrid sunfish, largemouth bass, northern pike, pumpkinseed, white sucker, yellow bullhead, yellow perch. Francis Lake is located in Isanti County, Minnesota.
What did the DNR fisheries survey find at Francis Lake?
- Minnesota DNR's Targeted Survey on June 19, 2024 caught 33.49 largemouth bass per hour of electrofishing at Francis Lake. Length samples in the latest survey that recorded them ran 0–0 inches. A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Francis Lake’s water-quality measurements separately, and the water-quality trend over 2 years of monitoring is improving. Catch rate is not a swim clearance and is not a weekly bite report.
When does Francis Lake thaw?
- Francis Lake typically has ice-out around Apr 11. Ice typically forms around Nov 16. The open water season is approximately 219 days.
Are there boat ramps on Francis Lake?
- Francis Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Francis Lake. Public access is listed as yes.
Can I fish at Francis Lake?
- Francis Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Seasons, size and bag limits, and whether you need a license are set by Minnesota's fish and wildlife agency, so check its current regulations before you go.
Explore Francis Lake across LakeQuality
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Where this data comes from
64 measurements from 2 monitoring stations, 2021–2024. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Minnesota Pollution Control Agency - Ambient Surface Water
MNPCA64 samples · 2021–2024
Analytical methods
- Field measurement/observation, generic method
- Phosphorus by Colorimetry
- 10200 H ~ Chlorophyll a-b-c Determination
Monitoring station identifiers (2)
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
Impairment status from EPA ATTAINS 303(d) database
Lake size & watershed from HydroLAKES (HydroSHEDS)
Lake details from Minnesota DNR LakeFinder
Named boat-access points from the USGS National Boat Ramps inventory
Ice data from Minnesota DNR Climate