Flat Lake
Becker County, Minnesota, near Richwood. DNR lake ID 03024200.
Flat Lake is a 1,970-acre lake in Becker County, Minnesota, near Richwood. Its deepest point reaches 16 ft. Summer water clarity averages 11.1 feet in Minnesota Pollution Control Agency monitoring, which places it in the mesotrophic nutrient class. It is not on the DNR infested waters list as of September 2026.
Buying or selling on Flat Lake? Ask us what lakeshore here actually sells for, which stretches of shoreline buyers compete for, and what’s coming up before it’s listed.
Tell us about your dream home on Flat LakeWhat’s my Flat Lake property worth?Call (218) 656-6469
Quick facts
| DNR lake ID | 03024200 |
|---|---|
| County | Becker County, near Richwood |
| Surface area | 1,970 acres |
| Maximum depth | 16 ft |
| Share under 15 ft | Not surveyed |
| Water clarity (summer) | 11.1 ft through 2025 |
| Phosphorus (summer) | 13.5 µg/L |
| Algae, chlorophyll-a (summer) | 3.8 µg/L |
| Nutrient class | Mesotrophic |
| Invasive species | Not on DNR infested waters list (Sept 2026) |
| Public water accesses | 0 |
Water quality
Summer averages from Minnesota Pollution Control Agency monitoring through 2025: clarity 11.1 ft, phosphorus 13.5 µg/L, algae (chlorophyll-a) 3.8 µg/L. Using the Carlson trophic state index, Flat Lake rates as mesotrophic.
Fishing regulations
No lake-specific regulation found in Minnesota Rules or the DNR sunfish list. Statewide and zone regulations apply.
Regulations change. Confirm with the DNR before fishing.
Invasive species
Not on the Minnesota DNR infested waters list as of September 2026. That means no confirmed listing, not a guarantee the lake is free of invasive species.
Public boat access
No public water access on DNR record.
Nearby lakes
- Balsam Lake 2.1 mi, Becker County
- Chippewa Lake 2.9 mi, Becker County
- Mary Yellowhead Lake 3.0 mi, Becker County
- Blackbird Lake 3.1 mi, Becker County
- Winter Lake 3.2 mi, Becker County
- Tamarack Lake 4.0 mi, Becker County
- Carman Lake 4.2 mi, Becker County
- Pine Lake 4.3 mi, Becker County
Questions about Flat Lake
How deep is Flat Lake?
Flat Lake reaches a maximum depth of 16 ft according to Minnesota DNR records.
How big is Flat Lake?
Flat Lake covers about 1,970 acres in Becker County, Minnesota.
How clear is Flat Lake?
Summer water clarity on Flat Lake averages 11.1 feet (Secchi depth) in MPCA monitoring through 2025. Its trophic state is mesotrophic.
Does Flat Lake have zebra mussels or other invasive species?
Flat Lake is not on the Minnesota DNR infested waters list as of September 2026. That means there is no confirmed listing; it is not a guarantee the lake is free of invasive species.
Are there lake homes for sale on Flat Lake?
Homes on Flat Lake come up for sale throughout the year, and some sell before they’re ever publicly advertised. Tell us what you’re looking for and our agents will run a custom search and send you matching homes on Flat Lake and nearby lakes, including off-market opportunities when available.
What is it like to live on Flat Lake?
A mid-size lake with room for boating and fishing, and summer clarity around 11.1 feet. Conditions vary by property, so walk the frontage and ask us what similar homes have sold for.
Are there special fishing regulations on Flat Lake?
No lake-specific regulation was found for Flat Lake in Minnesota Rules or the DNR sunfish list. Statewide and zone regulations apply.
Ask us about Flat Lake
Whether you’re buying, selling, or just curious, our team works Becker County lakes every day. Send us a note or call (218) 656-6469.
Sources: Minnesota DNR LakeFinder records, DNR fish surveys (latest not on record), DNR infested waters list (Sept 2026), Minnesota Rules 6264.0400 (April 2026), MPCA monitoring via the Water Quality Portal, DNR water access records (2023), LAGOS-US. Lakewide information from public data; it does not describe any specific property. Verify shoreline, bottom type, and depth at any frontage.