Kalmar Reservoir (KR-7)

Kalmar Reservoir (KR-7) is a flood control reservoir located west of Rochester on the north side of Olmsted County 156. A gravel parking lot is located on the northeastern side of the dam embankment with a crushed asphalt trail along the top of the dam. The reservoir is approximately 50 acres in size with a maximum depth of 10 feet near the outlet structure. Most of the reservoir is less than 5 feet in depth. The water depths are dependent on precipitation and are highly variable. Algae blooms are common in the summer months, due to agricultural runoff. Electrofishing was conducted along the dam face on April 11, 2025 to assess the size structure and abundance of Black Crappie, Bluegill, and Largemouth Bass populations. This survey was scheduled but was prioritized after ice fishing reports of anglers catching fish with lesions and necrotized tissue, primarily on fins. A single, 5.91 inch Black Crappie was sampled in this survey for a catch rate of 2.54 fish/hr. A total of 376 Bluegill were sampled in this survey for a catch rate of 953.4 fish/hr, up from the 260 fish/hr in 2021. The average length of bluegill was 5.67 inches, whereas the average size in 2021 was 3.0 inches. Twenty Largemouth Bass were sampled for a catch rate of 50.85 fish/hr. The average length was 9.73 inches. The largest was 16.26 inches and the smallest was 6.77 inches. Kalmar Reservoir is managed for a high density of medium sized Largemouth Bass to prey on smaller Bluegill and Black Crappies to maintain and improve their size structure. Five Yellow Perch were also sampled, this resulted in a catch rate of 12.71 fish/hr. They ranged in length from 2.91 inches to 10.12 inches with a mean of 5.64 inches.

Kalmar Reservoir (KR-7) is a flood control reservoir located west of Rochester on the north side of Olmsted County 156. A gravel parking lot is located on the northeastern side of the dam embankment with a crushed asphalt trail along the top of the dam. The reservoir is approximately 50 acres in size with a maximum depth of 10 feet near the outlet structure. Most of the reservoir is less than 5 feet in depth. The water depths are dependent on precipitation and are highly variable. Algae blooms are common in the summer months, due to agricultural runoff. Electrofishing was conducted on May 13, 2021 to assess the size structure and abundance of Black Crappie, Bluegill, and Largemouth Bass. Due to the presence of a significant amount of anglers, the electrofishing run along the dam face was moved farther offshore than normal. The waters along the dam face contain deeper habitat and historically better catch rates of larger fish. A single,10.3 inch Black Crappie was sampled in this survey for a catch rate of 1.2 fish/hr. This was the largest Black Crappie ever sampled in Kalmar Reservoir. The largest Black Crappie in 2014 was 8.39, with an average of 7.94 inches. A total of 216 Bluegill were sampled in this survey for a catch rate of 259 fish/hr, up from the 132 fish/hr in 2014. The average length of bluegill was 3 inches, whereas the average size in 2014 was 7.9 inches. Bluegill under 3 inches made up about 58 percent of the catch and are likely fish that hatched in 2020. A 9.6 inch Bluegill was sampled, this was the largest individual sampled ever.

Electrofishing was conducted on July 9, 2014 to assess the size structure of the Bluegill, Largemouth Bass, and Black Crappie populations. Sampling was conducted along the dam and the west shoreline for a total on-time of 29 minutes. A total of 64 Bluegill were collected at a rate of 132 fish/hr. Average Bluegill length was 6.9 inches and the largest Bluegill collected was 7.9 inches. Fifty-one Largemouth Bass were captured with a catch rate 105 fish/hr and a mean length of 11.4 inches. The largest bass collected was 17.3 inches. Black Crappie were captured at the rate of 52 fish/hr. Crappie mean length was 7.9 inches with the largest fish 8.4 inches. Changes in the size structure of the Bluegill population was noted in the 2010 survey and again in 2014. Mean length has increased from 5.17 inches in 2008 to 6.9 inches in 2014. The number of bluegills captured has declined while size has increased. The Largemouth Bass catch rate has remained fairly stable ranging from 125/hr in 2010 to 105/hr in 2014. However, the average size of Largemoouth Bass has increased from 4.2 inches in 2010 to 11.4 inches in 2014. Largemouth Bass were first stocked into Kalmar in 2008 and the population appears to be well established. Black Crappie abundance was low in the 2010 assessment, as just five were collected electrofishing. However, the 2012 and 2014 assessments have shown the abundance of crappie to have greatly increased. Mean length of Black Crappie increased from 6.9 inches in 2012 to 7.9 inches in 2014. Kalmar Reservoir continues to provide good angling for Bluegill and Largemouth Bass. The Black Crappie population is showing signs of improvement with harvestable size fish present.

Based on Minnesota DNR survey data, anglers target Largemouth Bass and Bluegill in Kalmar Reservoir (KR-7). See the full species list above for catch rates, size structure, and quality scores.

We don't have a confirmed public access point on record for Kalmar Reservoir (KR-7). Check the DNR LakeFinder page for current access details before you go.

The most recent Minnesota DNR survey data for the main sport fish in Kalmar Reservoir (KR-7) is from 2025.

No invasive species are on record for Kalmar Reservoir (KR-7) in Minnesota DNR data. Always clean, drain, and dry your equipment to help keep it that way.