Lake Harriet
Hennepin County, Minnesota341 acresView mapDirections
Minnesota PCA records this lake as “Harriet Lake.”
Minnesota PCA publishes the water-quality measurements for Lake Harriet. Here is what has been measured.
- Eutrophic
- Impaired · Impaired biota (cause unknown)
- 2 aquatic invasives
- 87 ft max depth
- Public access
Lake Harriet in Hennepin County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 9.7 ft visibility. Phosphorus: 189.5 µg/L. Chlorophyll-a (algae): 5.4 µg/L. Maximum depth: 87 ft. Surface area: 341.22 acres.
Minnesota DNR's Standard Survey on July 8, 2024 caught 6.00 walleye per gill net at Lake Harriet. Length samples in the latest survey that recorded them ran 7–26 inches. DNR survey details →
Lake Harriet is a 341-acre productive, nutrient-rich eutrophic lake in Hennepin County, Minnesota with a maximum depth of 87 feet (29-foot average). Overall water quality is declining over recent sampling years. The lake supports 15 documented fish species including black bullhead, black crappie, and bluegill. Public access is available with 1 public boat landing. Compared to the 80 other monitored lakes in Hennepin County, Lake Harriet ranks #13 for water quality.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-10-24. Methodology: how these readings are compared.
What Lake Harriet is good for
From access and monitoring records, not editorial picks.
- Boat launch1 documented ramp
- Fishing15 species recorded
- Ice seasonIce-out around Apr 7
- Deep water87 ft surveyed max depth
Swimming conditions
Readings onlyBacteria tested: low
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.
Based on E. coli testing, Lake Harriet never exceeded the EPA safe-swimming threshold (235 MPN/100mL) — on 0% of 6 samples across 6 seasons.
This is a historical summary of past testing, not a current condition — bacteria levels change quickly, especially after rain. Always check Minnesota’s current beach and health-department advisories before swimming.
Whether Lake Harriet 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 Lake Harriet
These are the measurements Minnesota PCA publishes for Lake Harriet, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Moderate clarity, visible to about 9.7 ft. Phosphorus 189.5 µg/L. Chlorophyll-a 5.4 µg/L. TSI 57.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 9.7ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 190µg/L | Poor GoodFairPoor |
| Chlorophyll-a (algae) | 5.4µg/L | Good GoodFairPoor |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 57 | Eutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
High nutrients, frequent algae, reduced clarity
Ask about Lake Harriet
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Lake Harriet typically sits around 50°F at the surface in October. Summer average is about 55°F. Usually warmest in Aug (about 56°F) and coldest in Jan (about 36°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (36°F) to its warmest (56°F).
Typical surface water temperature by month, from 3,238 field readings (2010–2025) via the EPA Water Quality Portal. See the full Lake Harriet water temperature breakdown →
Minnesota DNR's Standard Survey on July 8, 2024 caught 6.00 walleye per gill net at Lake Harriet. Length samples in the latest survey that recorded them ran 7–26 inches.
A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Lake Harriet’s water-quality measurements separately, and the water-quality trend over 6 years of monitoring is declining. Catch rate is not a swim clearance and is not a weekly bite report.
DNR Fisheries Survey Summary
12 surveys on file from MN DNR Fisheries. Most recent: 2024-07-08 (Standard Survey).
12 surveys on file · most recent 2024-07-08 (Standard Survey)
| Species | Catch rate (CPUE) | Size | Avg weight |
|---|---|---|---|
| Bluegill | 97.07 | 2–8 in 2024-07-08 | 0.14 lb |
| Yellow Perch | 18.14 | 5–10 in 2024-07-08 | 0.12 lb |
| Black Crappie | 10.67 | 3–10 in 2024-07-08 | 0.23 lb |
| Pumpkinseed | 4.91 | 3–7 in 2024-07-08 | 0.1 lb |
| Walleye | 2.59 | 7–26 in 2024-07-08 | 1.9 lb |
| Hybrid Sunfish | 2.57 | 3–7 in 2024-07-08 | 0.12 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.
Bluegill
Yellow Perch
Black Crappie
Pumpkinseed
From the 2024-07-08 survey
Harriet is a 341-acre (85 littoral acres) lake with a maximum depth of 82 feet. Harriet is located in south Minneapolis in eastern Hennepin County. Harriet is primarily managed for Walleye (fingerling stocked annually) and Muskellunge (fingerling stocked during even-numbered years), but includes catchable populations…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Lake Harriet. 3 reports on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — HarrietFisheries Lake Survey · MN DNR LakeFinder
- —Fish Stocking History — HarrietFish Stocking History · MN DNR LakeFinder
- —Public Water Access Sites — HarrietPublic Water Access Sites · MN DNR LakeFinder
Lake Details
Max depth
87 ft
Average depth
29 ft
Surface area
341 acres
Shoreline
2.7 mi
Littoral zone
25%
Share shallower than 15 ft
Public access
Yes
Listed by Minnesota PCA
Lake Size & Watershed
Watershed (drainage) area
9 sq mi
HydroLAKES / HydroSHEDS
Elevation
833 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Recreation & Access
- Lake HarrietPublic
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Stays via Stay22
Stays near Lake Harriet
Compare lakeside cabins, hotels, and vacation rentals near Lake Harriet in Hennepin 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 Lake Harriet
Prices for Oct 9–11, 4 adults. Change dates on the map below.
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Planning a whole trip? See where to stay at Minnesota’s top lakes →
Follow Lake Harriet’s readings
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Fish Species
Click a species to see every lake where it is documented.
Fishing Lake Harriet
Invasive & Introduced Species
Red chips are ecologically harmful invasive species. Gray chips are stocked or introduced fish that aren't a current ecological concern.
Water Quality Trend: Worsening
Based on 6 years of monitoring (2020–2025).
Water clarity
Worsening6 years
Phosphorus
Improving-5.39 µg/L/yr6 years
Chlorophyll-a
Worsening+0.65 µg/L/yr6 years
Ice season
Typical ice-out
Apr 7
Earliest Mar 7, 2017 · Latest May 2, 2018
Typical ice-in
Dec 10
Earliest Nov 25, 1996 · Latest Jan 14, 2024
Most recent ice-out
Apr 1
2026
160 observations · Minnesota PCA ice records
EPA Impairment Status
Lake Harriet 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, Fish consumption.
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit MN27-0016-00 · Official waterbody report
Nearby Lakes in Hennepin County
Frequently asked questions about Lake Harriet
Where is Lake Harriet?
- Lake Harriet is a lake in Hennepin County, Minnesota. Its water-quality measurements are published by Minnesota PCA and shown on this page as reported.
What is the water quality of Lake Harriet?
- Lake Harriet in Hennepin County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 9.7 ft visibility. Phosphorus: 189.5 µg/L. Chlorophyll-a (algae): 5.4 µg/L. Maximum depth: 87 ft. Surface area: 341.22 acres.
Is Lake Harriet safe to swim in?
- Based on E. coli testing, Lake Harriet never exceeded the EPA safe-swimming threshold (235 MPN/100mL) — on 0% of 6 samples across 6 seasons. That is a historical summary of past bacteria testing, not a current reading and not a swimming clearance. Bacteria levels can spike quickly after heavy rain, so whether Lake Harriet is safe to swim in today is a call for Minnesota's water agency and the county health department; check their current beach advisories before you swim.
What is the water temperature of Lake Harriet?
- Lake Harriet typically sits around 50°F at the surface in October, from 3,238 EPA Water Quality Portal field readings (2010–2025). That is a typical value for the month, not a live reading.
How deep is Lake Harriet?
- Lake Harriet has a maximum depth of 87 feet and an average depth of 29 feet. The lake covers 341.22 acres.
What fish are in Lake Harriet?
- Fish species found in Lake Harriet include black bullhead, black crappie, bluegill, brown bullhead, common carp, green sunfish, hybrid sunfish, largemouth bass, muskellunge, northern pike, pumpkinseed, walleye, white sucker, yellow bullhead, yellow perch. Lake Harriet is located in Hennepin County, Minnesota.
What did the DNR fisheries survey find at Lake Harriet?
- Minnesota DNR's Standard Survey on July 8, 2024 caught 6.00 walleye per gill net at Lake Harriet. Length samples in the latest survey that recorded them ran 7–26 inches. A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Lake Harriet’s water-quality measurements separately, and the water-quality trend over 6 years of monitoring is declining. Catch rate is not a swim clearance and is not a weekly bite report.
When does Lake Harriet thaw?
- Lake Harriet typically has ice-out around Apr 7. Ice typically forms around Dec 10. The open water season is approximately 247 days.
Are there boat ramps on Lake Harriet?
- Lake Harriet has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Lake Harriet. Public access is listed as yes.
Can I fish at Lake Harriet?
- Lake Harriet 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 Lake Harriet across LakeQuality
Depth, room, public access, and the state wake-sport rules
Fish species and the cleanest lakes across Minnesota
Fish species and best lakes in Hennepin County
Species activity outlook by water temperature and season
Where to stay at Minnesota's top lakes, each with its readings
Lakes in the Crow River Watershed, ranked by water quality
Minnesota's cleanest lakes, ranked on agency measurements
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State Parks Near Lake Harriet
Other Lakes in Minnesota
Eutrophic Lakes in Minnesota
Where this data comes from
1,650 measurements from 2 monitoring stations, 2020–2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Minnesota Pollution Control Agency - Ambient Surface Water
MNPCA1,650 samples · 2020–2025
Analytical methods
- Field measurement/observation, generic method
- 4500 P E ~ Phosphorus in Water by Colorimetry- Ascorbic Acid Method
- 10200 H ~ Chlorophyll a-b-c Determination
- Turbidity, Nephelometric Method
- Turbidity, Probe Method
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