Sullivan Lake
Sullivan Lake in Wright County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 6 ft visibility. Maximum depth: 58 ft. Surface area: 70.58 acres.
- Clarity
- 6 ft
- Typical in August
- 54°F
- Max depth
- 58 ft
- Area
- 71 acres
- Trend
- ↓ Declining
- Public access
- Yes
- Ice-out
- Apr 3
Next lake in Wright County
Why Sullivan 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 Sullivan Lake, the only measurement available is water clarity, which is not a water-quality indicator on its own — EPA's National Lakes Assessment does not grade clarity. Sampling here has recorded water clarity, but not phosphorus and algae (chlorophyll-a).
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.
Sullivan Lake is a 71-acre lake in Wright County, Minnesota with a maximum depth of 58 feet (16-foot average). Overall water quality is declining over recent sampling years. The lake supports 11 documented fish species including black bullhead, black crappie, and bluegill. Public access is available with 1 public boat landing.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2024-09-28. Grade methodology: LakeGrade methodology.
Watch Sullivan Lake water quality
Subscribe for LakeQuality updates by email. No spam, unsubscribe anytime.
Swimming Safety
Not ratedLimited data
Not rated for swimming — there is not enough monitoring data to judge this lake
Water quality measurements for Sullivan Lake
These readings exist but do not meet the evidence bar for an A–F grade — see why.
Murky, only visible to about 6 ft. Trophic State Index: 51.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 6 ft | Not graded |
| Phosphorus | No recent samples | |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) | 51 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Where to stay near Sullivan Lake
Compare lakeside cabins, hotels, and vacation rentals near Sullivan Lake in Wright 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 Sullivan Lake
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 →
Water Temperature
Sullivan Lake typically sits around 54°F at the surface in August. Summer average is about 56°F. Usually warmest in Sep (about 59°F) and coldest in May (about 46°F). These are typical values by month — not a live reading.
Typical surface water temperature by month, from 63 field readings (2017–2018) via the EPA Water Quality Portal. See the full Sullivan Lake water temperature breakdown →
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 58 ft |
| Average Depth | 15.5 ft |
| Surface Area | 71 acres |
| Shoreline Length | 1.7 mi |
| Littoral Zone | 58% |
| Public Access | Yes |
Lake Size & Watershed
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Recreation & Access
- Sullivan LakePublic
Fish Species
Click a species to see every graded lake where it is documented.
Fishing Sullivan Lake
DNR Fisheries Survey Summary
5 surveys on file from MN DNR Fisheries. Most recent: 2020-07-06 (Standard Survey).
Top Species by Catch Rate
| Species | Avg CPUE | Avg Weight |
|---|---|---|
| Bluegill | 27.70 | 0.15 lb |
| Yellow Bass | 13.52 | 0.48 lb |
| Black Bullhead | 7.04 | 0.63 lb |
| Hybrid Sunfish | 6.14 | 0.14 lb |
| Black Crappie | 5.60 | 0.2 lb |
| Brown Bullhead | 4.96 | 0.68 lb |
CPUE = catch per unit effort, averaged across surveys (excludes juvenile shoreline seining). Higher CPUE = more abundant in standardized sampling.
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 Bass
Black Bullhead
Hybrid Sunfish
From the 2020-07-06 survey
Sullivan Lake is a small (73 acre), highly developed lake located between Buffalo and Maple Lake in Wright County. The lake has a maximum depth of 58 feet with moderate water quality with an average summer water clarity of seven (7) feet. There is one (1) public access located on the east side of the lake. A lake…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Sullivan Lake. 3 reports on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — SullivanFisheries Lake Survey · MN DNR LakeFinder
- —Aquatic Plant Report — Sullivan (2004)Aquatic Plant Report · MN DNR LakeFinder
- —Public Water Access Sites — SullivanPublic Water Access Sites · MN DNR LakeFinder
Water Quality Trend: ↓ Declining
Based on 5 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | ↓ Declining | -0.289 m/yr | 5 |
Ice Season
Historical ice data from Minnesota DNR (4 observations).
| Earliest | Latest | |
|---|---|---|
| Ice-Out | 2016-03-15 (2016) | 2008-04-23 (2008) |
| Ice-In | 2007-12-01 (2007) | 2007-12-01 (2007) |
Most recent ice-out: 2020-04-02
EPA Impairment Status
Sullivan Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 5).
Causes of impairment
Source: EPA ATTAINS assessment unit MN86-0134-01 · Official waterbody report · Matched by proximity (2.19 km)
Graded lakes near Sullivan Lake
Sullivan Lake has no grade, but these lakes within a short drive do.
Nearby Lakes in Wright County
Frequently asked questions about Sullivan Lake
What is the water quality grade for Sullivan Lake?
- Sullivan Lake in Wright County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 6 ft visibility. Maximum depth: 58 ft. Surface area: 70.58 acres.
Is Sullivan Lake safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Sullivan Lake is not rated for water quality — its monitoring record does not meet the evidence bar. Always check local health department advisories before swimming.
What is the water temperature of Sullivan Lake?
- Sullivan Lake typically sits around 54°F at the surface in August, from 63 EPA Water Quality Portal field readings (2017–2018). That is a typical value for the month, not a live reading.
How deep is Sullivan Lake?
- Sullivan Lake has a maximum depth of 58 feet and an average depth of 15.5 feet. The lake covers 70.58 acres.
What fish are in Sullivan Lake?
- Fish species found in Sullivan Lake include black bullhead, black crappie, bluegill, bowfin (dogfish), brown bullhead, green sunfish, hybrid sunfish, northern pike, pumpkinseed, yellow bullhead, yellow perch. Sullivan Lake is located in Wright County, Minnesota.
When does Sullivan Lake thaw?
- Sullivan Lake typically has ice-out around Apr 3.
Are there boat ramps on Sullivan Lake?
- Sullivan Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Sullivan Lake. Public access is listed as yes.
Explore Sullivan Lake across LakeGrade
Fish species and top-graded lakes across Minnesota
Fish species and best lakes in Wright County
Species activity outlook by water temperature and season
Where to stay at Minnesota's top lakes, each with its grade
Lakes in the Crow River Watershed, ranked by water quality
Minnesota's cleanest and most-polluted lakes, ranked
More Minnesota Lake Rankings
State Parks Near Sullivan Lake
Other Lakes in Minnesota
Eutrophic Lakes in Minnesota
Where this data comes from
53 measurements from 1 monitoring station, 2020–2024. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Minnesota Pollution Control Agency - Ambient Surface Water
MNPCA53 samples · 2020–2024
Analytical methods
- Field measurement/observation, generic method
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
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