Lilly Lake
Dakota County, Minnesota8 acresView mapDirections
Minnesota PCA publishes the water-quality measurements for Lilly Lake. Here is what has been measured.
- Hypereutrophic
- Eurasian watermilfoil
- 8 ft max depth
- Limited data
Lilly Lake in Dakota County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 2 ft visibility. Phosphorus: 145 µg/L. Chlorophyll-a (algae): 64 µg/L. Maximum depth: 8 ft. Surface area: 8.08 acres.
Minnesota DNR's Standard Survey on June 3, 2013 caught 0.20 northern pike per trap net at Lilly Lake. DNR survey details →
Lilly Lake is a 8-acre highly nutrient-loaded hypereutrophic lake in Dakota County, Minnesota with a maximum depth of 8 feet. Overall water quality is declining over recent sampling years. Limited fish-species data available. No public access — the lake is private or restricted. Compared to the 44 other monitored lakes in Dakota County, Lilly Lake ranks #45 for water quality.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2024-09-05. Methodology: how these readings are compared.
Swimming conditions
Readings onlyLimited data
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. Check local advisories before you swim.
Whether Lilly 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 Lilly Lake
These are the measurements Minnesota PCA publishes for Lilly 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 145 µg/L. Chlorophyll-a 64 µg/L. TSI 72.
| 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 | 145µg/L | Poor GoodFairPoor |
| Chlorophyll-a (algae) | 64µg/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. | 72 | Hypereutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Very high nutrients, dense algae, poor clarity
Ask about Lilly Lake
Answers come straight from the public measurements and survey records on this page.
Minnesota DNR's Standard Survey on June 3, 2013 caught 0.20 northern pike per trap net at Lilly Lake.
A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Lilly Lake’s water-quality measurements separately, and the water-quality trend over 2 years of monitoring is declining. Catch rate is not a swim clearance and is not a weekly bite report.
DNR Fisheries Survey Summary
3 surveys on file from MN DNR Fisheries. Most recent: 2013-06-03 (Standard Survey).
3 surveys on file · most recent 2013-06-03 (Standard Survey)
| Species | Catch rate (CPUE) | Size | Avg weight |
|---|---|---|---|
| Bluegill | 42.67 | 3–5 in 2013-06-03 | 0.12 lb |
| Black Bullhead | 37.30 | 4–9 in 2013-06-03 | 0.15 lb |
| Green Sunfish | 8.27 | 2–5 in 2013-06-03 | 0.1 lb |
| Pumpkinseed | 3.70 | 2–5 in 2013-06-03 | 0.14 lb |
| Hybrid Sunfish | 2.73 | 2–7 in 2013-06-03 | 0.17 lb |
| Black Crappie | 2.10 | 7–10 in 2013-06-03 | 0.48 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
Black Bullhead
Green Sunfish
Pumpkinseed
From the 2013-06-03 survey
Thompson Lake is a small 10 acre lake located in Thompson County Park (Dakota County Parks) within the city limits of West St. Paul. The lake has a maximum depth of eight feet and receives primarily stormwater inputs from the 169 acre surrounding watershed. A spillway outlet structure maintains the water level and…
Lake Details
Max depth
8 ft
Surface area
8 acres
Shoreline
0.5 mi
Littoral zone
87%
Share shallower than 15 ft
Public access
No
Listed by Minnesota PCA
Stays via Stay22
Stays near Lilly Lake
Compare lakeside cabins, hotels, and vacation rentals near Lilly Lake in Dakota 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 Lilly Lake are listed below.
Top-rated places to stay near Lilly Lake
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 →
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Fishing Lilly Lake
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 readings over time
2 seasons of samples on record (2024–2025). Calling a direction takes at least 4 years of the same measurement.
Water clarity
Worsening2 years
Regulated Pollution Sources Nearby
7 EPA-permitted facilities operate within about 5 miles of Lilly Lake under Clean Water Act (NPDES) discharge permits, including 2 classified by the EPA as major dischargers. 1 facility has a reported Clean Water Act violation in the past three years.
- Met Council - Metropolitan WwtpSaint Paul · 1.5 mi away · NPDES MN0029815Major
- Met Council - Mississippi Basin Total PhosphorusSaint Paul · 1.5 mi away · NPDES MN0070629Major
- Captain Ken'S Foods IncSaint Paul · 1.6 mi away · NPDES MN0059765Recent violation
- Magellan Pipeline MinneapolisSaint Paul, City Of · 0.6 mi away · NPDES MN0045896
- Saint Paul Port Authority-Multiple Dredge/Southport Terminal Storage SitesSaint Paul · 0.8 mi away · NPDES MN0056081
- Flint Hills Resources L.P.Saint Paul · 1.7 mi away · NPDES MN0064696
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.
Nearby Lakes in Dakota County
Frequently asked questions about Lilly Lake
Where is Lilly Lake?
- Lilly Lake is a lake in Dakota County, Minnesota. Its water-quality measurements are published by Minnesota PCA and shown on this page as reported.
What is the water quality of Lilly Lake?
- Lilly Lake in Dakota County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 2 ft visibility. Phosphorus: 145 µg/L. Chlorophyll-a (algae): 64 µg/L. Maximum depth: 8 ft. Surface area: 8.08 acres.
Is Lilly Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
How deep is Lilly Lake?
- Lilly Lake has a maximum depth of 8 feet. The lake covers 8.08 acres.
What did the DNR fisheries survey find at Lilly Lake?
- Minnesota DNR's Standard Survey on June 3, 2013 caught 0.20 northern pike per trap net at Lilly Lake. A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Lilly Lake’s water-quality measurements separately, and the water-quality trend over 2 years of monitoring is declining. Catch rate is not a swim clearance and is not a weekly bite report.
Can I fish at Lilly Lake?
- Public access to Lilly Lake is listed as no on the lake record, so confirm before you make the trip. 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 Lilly Lake across LakeQuality
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Fish species and best lakes in Dakota County
Species activity outlook by water temperature and season
Where to stay at Minnesota's top lakes, each with its readings
Lakes in the Minnesota River Watershed, ranked by water quality
Minnesota's cleanest lakes, ranked on agency measurements
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State Parks Near Lilly Lake
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Where this data comes from
28 measurements from 1 monitoring station, 2024. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Minnesota Pollution Control Agency - Ambient Surface Water
MNPCA28 samples · 2024
Analytical methods
- Field measurement/observation, generic method
- Phosphorus by Colorimetry
- Analysis of Chlorophyll in Periphyton and Plankton
Monitoring station identifiers (1)
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
Regulated discharger data from EPA ECHO (ICIS-NPDES)
Lake details from Minnesota DNR LakeFinder