
Grant County Lake Quality
Wisconsin, 5 lakes, measured by Wisconsin DNR
Grant County holds 5 monitored lakes. With a sample that small the county-level summary describes those specific waters, not necessarily every water body in the county. 3 of those lakes carry recent nutrient and algae readings. The county-level summary describes that subset, not every water body listed. Most monitored lakes in Grant County are productive, shallow basins; each lake page shows its own phosphorus and chlorophyll-a readings beside the EPA condition class.
Most of the county's monitored lakes are shallow, under 50 feet, which means wind keeps the water column mixed all summer and sediment-bound phosphorus releases back into the surface layer whenever the bottom is disturbed. Jones Slough Lake has the lowest nutrient and algae readings in the county.
Where to stay near Grant County
Top-rated places to stay near Grant County
Prices for Oct 9–11, 4 adults. Change dates on the map below.
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 trip to Grant County?
Get lake water-quality updates plus the best cabin & lodging deals near Grant County — straight to your inbox. No spam, unsubscribe anytime.
Quick Answers for Grant County
Planning a trip? Check special fishing regulations for Jones Slough Lake — or browse the full Wisconsin regulations index.
All Lakes in Grant County
5 lakes · 3 ranked on readings, 2 without enough sampling3 lakes ranked on readings · 2 without enough sampling, hidden
| # | Lake | Clarity | Phosphorus | Algae | Trophic | Max Depth | Access |
|---|---|---|---|---|---|---|---|
| 1 | Jones Slough LakeGrant | 4.9 ft | 31 µg/L | No recent samples | No recent samples | No recent samples | ✓ Public |
| 2 | Rice LakeGrant | 4.6 ft | 66.6 µg/L | No recent samples | No recent samples | 5 ft | ✓ Public |
| 3 | Unknown LakeGrant | 2.4 ft | 135.5 µg/L | No recent samples | No recent samples | No recent samples | Not recorded |
| Gassner LakeGrant | No recent samples | No recent samples | No recent samples | No recent samples | No recent samples | Not recorded | |
| Long SloughGrant | No recent samples | No recent samples | No recent samples | No recent samples | No recent samples | Not recorded |
NR = no nutrient or algae reading on record. The measurements are published as the authority reports them. Where the data comes from.
Lake Match
Which lake suits how you actually use one?
Six questions — swimming, fishing, quiet, cabins, drive time — and a shortlist of lakes that fit, with the water quality behind each one.
Other Counties in Wisconsin
Browse every Wisconsin lake, or the full directory of lakes across all United States (49 states), Canada (Ontario, Québec, Nova Scotia, British Columbia and Newfoundland and Labrador), and 38 other country hubs..
Source: the Wisconsin Department of Natural Resources. See data sources.