Albert Lea Lake Management and Invasive Species Control Structure

The Shell Rock River Watershed District (SRRWD) encompasses 246-square miles in Freeborn County. The District includes 11 lakes that drain to the Shell Rock River, which flows into the Cedar River. Among the District’s lakes are Fountain Lake and Albert Lea Lake, located within the City of Albert Lea. These lakes are central to Albert Lea’s tourism industry and its identity.

The previous Albert Lea Lake outlet structure and access bridge, installed in 1922, was in need of repair. The Albert Lea Lake Management and Invasive Species Control Project replaced the fixed-crest dam with a rock-arch rapids feature to control water levels. A lake level management structure was also constructed, as well as an electric fish barrier to prevent silver, bighead, and common carp and other benthic feeding fish from entering the lake.

The project is expected to result in improved aquatic habitat, improved waterfowl nesting, breeding, and feeding habitat, an increase in desirable fish populations, and improved water quality and clarity for years to come. Specific benefits are outlined below.
1. Rock-Arch Water-Level Control: The SRRWD replaced the old fixed-crest dam with a series of rock arches to provide a naturalized outlet to Albert Lea Lake. The upper-most rock arch is controlling the normal water level with the help of metal sheeting. There are two more rock arches behind the first, totaling 3 rock arches.

2.  Lake Level Management Structure: The installation of the structure to facilitate lake-level management gives the SRRWD flexibility to take action benefiting the health of the lake. Periodic lowering of lake elevations allows maximum in-lake sediment compaction, improvement of water clarity due to reduction in wind-generated turbidity, and time for plant colonization of shoreline and shallow-water areas. The resulting improvement in aquatic plant health benefits the entire lake system.

3.  Electric fish barrier:  An electric fish barrier was installed and is used to reduce the population of common carp (Cyprinus carpio) in Albert Lea Lake and to prevent the introduction of Bighead and Silver (Asian) Carp. Common carp uproot and consume aquatic vegetation, disturb and re-suspend phosphorous-rich sediments. The resulting increase in turbidity reduces light penetration—discouraging rooted plant growth—and contributes to algal blooms responsible for oxygen depletion. The destruction of aquatic vegetation by large populations of foraging fish also impacts waterfowl nesting, breeding, and feeding habitat, shoreline and littoral habitat, and game fish spawning habitat.

Design and engineering of the project started in late 2013. Contracts and associated agreements for the dam were made in early 2014. The order of operations for the construction of the project includes:
•    Installation of the cofferdam
•    Construction of the water diversion channel
•    Removal of the old dam and bridge
•    Installation of the metal sheeting that holds the lake level
•    Placement of the first rock arch along the sheeting
•    Installation of the footings for the concrete work
•    Concrete work for the fish barrier
•    Concrete work for the draw down structure
•    Finalize/seal all concrete
•    Placement of remaining rock arches
•    Removal of the cofferdam and water diversion channel
•    Installation and fine tuning of the fish barrier component

The main construction of the projects where completed in the spring of 2015. At the end of 2015, some calibrations of the electric components were needed on the electric fish barrier. After the ice melt in the spring of 2016, those changes were made to fine tune the barrier. The Albert Lea Lake Management and Invasive Species Control Structure is now fully complete.

The outlet, fish passage, and fish barrier worked in harmonization as part of the District’s overall management plan. Similar to the Wedge Creek, White Lake, and Mud Lake efforts, the anticipated outcome for Albert Lea Lake is restoration of rooted aquatic vegetation, fish and wildlife habitat, and enhanced water quality—all of which will serve to increase community use of this important recreational resource.

 The existing Albert Lea Lake outlet structure and access bridge, installed in 1922, are in need of repair.The proposed project would replace the fixed-crest dam with a rock-arch rapids feature to control water levels and allow fish passage (see concept drawing). A lake level management structure would also be constructed, as well as an electric barrier to prevent silver, bighead, and common carp and other benthic feeding fish from entering the lake.

This project is expected to result in improved aquatic habitat, improved waterfowl nesting, breeding, and feeding habitat, an increase in desirable fish populations, and improved water quality and clarity. It has been identified as a high priority in the SRRWD Management Plan, developed with public participation, and subject to public review and approval by the SRRWD Board. Specific benefits are outlined below.

1.  Rock-Arch Water-Level Control and Fish Passage: Replacing the existing fixed-crest dam with a series of rock arches will provide a naturalized outlet to Albert Lea Lake, with the upper-most rock arch controlling the normal water level. The arches will also provide fish passage, allowing northern pike to move upstream from the Shell Rock River to spawn in the lake. Northern Pike typically spawn in March and April, while carp spawning/movement typically does not start until May. A fish passage—in combination with an electric fish barrier activated in May to preclude carp—will increase the population of Northern Pike, natural predators of carp. Albert Lea Lake populations of Northern Pike and Bluegill (also a carp egg predator) are currently below Minnesota DNR norms for similar lakes.

2.  Lake Level Management Structure: Installation of a structure to facilitate lake-level management gives the SRRWD flexibility to take action benefiting the health of the lake. Periodic lowering of lake elevations allows maximum in-lake sediment compaction, improvement of water clarity due to reduction in wind-generated turbidity, and time for plant colonization of shoreline and shallow-water areas. The resulting improvement in aquatic plant health benefits the entire lake system.

3.  Electric fish barrier: An electric fish barrier will be used to reduce the population of common carp (Cyprinus carpio) in Albert Lea Lake and to prevent the introduction of Bighead and Silver (Asian) Carp.

Common carp uproot and consume aquatic vegetation, disturb and re-suspend phosphorous-rich sediments. The resulting increase in turbidity reduces light penetration—discouraging rooted plant growth—and contributes to algal blooms responsible for oxygen depletion. The destruction of aquatic vegetation by large populations of foraging fish also impacts waterfowl nesting, breeding, and feeding habitat, shoreline and littoral habitat, and game fish spawning habitat.

Asian Carp multiply rapidly and are voracious eaters, depleting food resources. The leaping ability of the Silver Carp also poses a danger to boaters and skiers. According to a 2010 news story in the Cedar Rapids Gazette, Asian carp have migrated past the 5-in-1 Dam in Cedar Rapids, Iowa, moving up the Cedar River to Black Hawk County—where the Cedar and the Shell Rock River join. The distance from this point to Albert Lea Lake is only about 100 miles. While there is not general agreement about the threat posed by Asian carp in lake waters, if this does become a concern the barrier could be used year-round and an alternative fish management plan developed.

The SRRWD has a proven track record of success with fish barriers. The fish barriers upstream of Albert Lea Lake—at Wedge Creek and White Lake (partially funded by 2009 Outdoor Heritage Funds) and Mud Lake—have improved habitat and water clarity in the upstream areas. Improved habitat is demonstrated by increased sightings of aquatic fur bearers and waterfowl, with 15 waterfowl species sighted during the fall migration. Improvements in water clarity are demonstrated by secchi disk readings on Fountain Lake (connected to these water bodies), which were the best on record in 2010.

The proposed outlet, fish passage, and fish barrier will work as part of the District’s overall management plan. Similar to the Wedge Creek, White Lake, and Mud Lake efforts, the anticipated outcome for Albert Lea Lake is restoration of rooted aquatic vegetation, fish and wildlife habitat, and enhanced water quality—all of which will serve to increase community use of this important recreational resource. The strategy of carp/rough fish control and exclusion is known to be effective. This program is endorsed by the Department of Natural Resources (DNR) Fishery and Wildlife Divisions and the Minnesota Pollution Control Agency and conducted with their technical assistance and cooperation.

This project is consistent with recommendations of the 2004 Shell Rock River Watershed Management Plan (Appendix B & J). It is also noted in the Albert Lea Lake Management Plan, as part of the Freeborn County Comprehensive Water Plan 2006-2015. Other applicable plans include the Minnesota Conservation and Preservation Plan Phase II provisions that address the control of invasive species, restoration of shallow lakes, water quality improvements in impaired waters, and  protection and enhancement of fish and waterfowl breeding habitat (pg. 30-96); and the 2009 Minnesota State Management Plan for Invasive Species. Activities are also within the goals of the Basin Alliance for the Lower Mississippi in Minnesota (BALMM).

This project is a component of the 2011 Restoring Native Habitat/Water Quality to the Shell Rock River Project funded by the Lessard-Sams Outdoor Heritage Fund for the fee-title acquisition of the headwaters of the Shell Rock River. The land has been acquired and will be turned over to the DNR to be operated under an Aquatic Management Area Management Plan.

There are no known opponents or anticipated barriers to project completion. These efforts will be highly visible and seen as a benefit to the entire region. They are endorsed by the local Chamber of Commerce, Convention and Visitors Bureau, Freeborn County, City of Albert Lea, DNR and Fountain Lake Sportsmen’s Club.