Lake Ann is 119 acres with a maximum depth of 40 feet. The water clarity is good and phosphorous is low. Invasive species in this lakes are Curlyleaf Pondweed and Eurasian Watermilfoil. Blue Gill, White Sucker, Black Crappie, and Yellow Perch are the most abundant common fish species found in Lake Ann. Lake Ann Park is a community park and has boat ramp, swimming beach, trails and picnic areas, and fishing dock amenities.
The Riley Purgatory Bluff Creek Watershed District initiated an update of the Use Attainability Analysis for Lake Lucy and Lake Ann. Lake Ann is directly connected to Lake Lucy by a small channel along the northern edge. The UAA was conducted in order to assess the water quality in both lakes.