Little Archibald Lake

Little Archibald Lake earns an A — water clarity, phosphorus, and chlorophyll-a all rate among the best monitored waters in Oconto County. Clarity, phosphorus, and chlorophyll-a all rate similarly, so there is no obvious single lever to pull on watershed management.

Mesotrophic conditions dominate at Little Archibald Lake: enough nutrients for a healthy fishery, not so much that algal blooms become a chronic problem. Little Archibald Lake is unusually deep for Wisconsin at 65 ft, which buffers the lake against summer warming and helps the deep water stay oxygenated. The lake is compact at 54 acres, with partial shoreline records and little volume to buffer nutrient inputs. Among the 62 graded lakes in Oconto County, Little Archibald Lake sits at rank 19, above the county median.

No invasive species are currently listed at Little Archibald Lake — the lake remains off the Wisconsin infested-waters roster. Bass fishing is part of the appeal: the species list runs to 2, anchored by largemouth and/or smallmouth bass. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.