Union Lake
About Union Lake
Union Lake is an 887-acre lake near Erskine in Polk County, Minnesota. It reaches 83 feet at its deepest point, and has roughly 14.6 miles of shoreline. By surface area it ranks No. 2 among the 13 Polk County lakes in this directory. DNR surveys put average water clarity at about 6.9 feet.
Minnesota DNR fisheries surveys list 12 fish species here, including walleye, northern pike, largemouth bass, black crappie, bluegill, and pumpkinseed. The DNR has stocking records for the lake, so check the stocking report for the most recent species and year classes. The most recent fisheries survey on file dates to 2022.
There is one public boat launch (asphalt surface) managed by the Minnesota DNR. The lake is listed as infested with Eurasian watermilfoil and zebra mussel — clean, drain and dry your boat and gear before leaving. Ice typically goes out around April 24, based on 11 years of DNR ice-out records.
Plan Your Visit to Union Lake
- 887 acres, up to 83 feet deep, near Erskine
- 1 public boat launch (asphalt) — managed by the Minnesota DNR
- Game fish on the DNR survey: walleye, northern pike, largemouth bass, black crappie, bluegill, and pumpkinseed
- Average water clarity around 6.9 feet
- Listed as infested with Eurasian watermilfoil and zebra mussel — clean, drain and dry before you leave
Access & Fees
- Public access
- 1 public boat launch (asphalt)
- Launch fee
- Free at DNR accesses
- Managed by
- Minnesota DNR
Conditions
- Surface area
- 887 acres
- Max depth
- 83 ft
- Shoreline
- 14.6 mi
- Water clarity
- 6.9 ft
- Shallows (under 15 ft)
- 394 acres
Rules & Regulations
- A Minnesota fishing license is required for anglers 16 and older
- Drain plugs must be out and all water drained before leaving any access; remove aquatic plants from boats and trailers
- Children under 10 must wear a life jacket on a boat that is underway
Facilities
- 1 public boat launch (asphalt)
Best For
- Walleye fishing
- Ice fishing
- Ice is never completely safe — check thickness yourself before walking or driving on any lake
Angler's Report
Minnesota DNR LakeFinder- Species on survey
- 12
- Game fish
- 7
- Stocked
- Yes
- Last DNR survey
- 2022
- Special regulations
- No
- Fishing pier
- No
- Ice fishing
- Yes
- Boat launch
- Yes
Fishing data: Minnesota Department of Natural Resources. Regulations change — confirm with the current DNR fishing regulations.
Ice-Out History
- Median ice-out
- April 24
- Years of record
- 11
- Earliest
- April 6, 2017
- Latest
- May 8, 1996
- Most recent
- May 4, 2023
See every lake on the ice-out tracker. Ice-out data: Minnesota DNR State Climatology Office.
Activities
Amenities
Fish Species
Plan your trip to Union Lake
Compare Union Lake against the top-ranked lakes nearby, then map your route.
See how Union Lake ranks among fishing lakes nearby.
See how Union Lake ranks among boating lakes nearby.
See how Union Lake ranks among paddling lakes nearby.
See how Union Lake ranks among ice fishing lakes nearby.
Nearby Lakes
Lake Sarah
70 out of 100 Lake ScorePolk · Erskine366 acres
3 miles away
Lake Crystal
33 out of 100 Lake ScorePolk · Erskine118 acres
3.3 miles away
Cameron Lake
47 out of 100 Lake ScorePolk · Erskine225 acres
6.4 miles away
Maple Lake
67 out of 100 Lake ScorePolk · Mentor1,641 acres
6.6 miles away
Badger Lake
55 out of 100 Lake ScorePolk · Erskine256 acres
7.5 miles away
Cable Lake
27 out of 100 Lake ScorePolk · Mentor194 acres
7.5 miles away
Frequently Asked Questions
Where is Union Lake?
Union Lake is in Polk County, Minnesota, near Erskine. It covers 887 acres and reaches 83 feet deep.
How big and how deep is Union Lake?
Union Lake covers 887 acres with about 14.6 miles of shoreline. Its maximum depth is 83 feet.
What fish can you catch at Union Lake?
Minnesota DNR surveys list Walleye, Northern Pike, Largemouth Bass, Black Crappie, Bluegill, Pumpkinseed, and Yellow Perch and other species. A Minnesota fishing license is required for anyone 16 and older.
Is there a public boat launch on Union Lake?
Yes. Union Lake has 1 public boat launch (asphalt), managed by the Minnesota DNR. DNR public water accesses are free to use.
Can you swim at Union Lake?
There is no mapped public swim beach at Union Lake. Minnesota's public waters are open to swimming where you have legal access, but there are no lifeguards or water-quality monitoring away from designated beaches.
Is Union Lake stocked?
Yes. The Minnesota DNR has stocking records for Union Lake; species and numbers vary by year, so see the stocking report on DNR LakeFinder.
When does the ice go out on Union Lake?
The median ice-out date is April 24, from 11 years of Minnesota DNR records. The earliest on record is April 6, 2017 and the latest is May 8, 1996.
Does Union Lake have invasive species?
Yes. The DNR lists Union Lake as infested with Eurasian watermilfoil and zebra mussel. State law requires you to clean off plants, pull the drain plug and drain all water before leaving the access.