Roseau Lake Rehabilitation
$2,763,000 the second year is to the commissioner of natural resources to acquire land in fee and permanent conservation easements for wildlife management purposes in Roseau County under Minnesota Statutes, section 86A.05, subdivision 8, to restore and enhance wildlife habitat. A list of proposed land acquisitions and restorations and enhancements must be provided as part of the required accomplishment plan.
Improved availability and improved condition of habitats that have experienced substantial decline - The site will be monitored through a joint 5 year monitoring plan between the RRWD and DNR. Monitoring will include an evaluation of bird species use; plant community condition; water quality; water quantity as measured against project outcomes and current conditions. .Increased waterfowl and upland bird migratory and breeding success - DNR staff does ongoing annual surveys of waterfowl breeding pairs and brood numbers on Roseau Lake. In addition, annual invertebrate and vegetation surveys will be undertaken once sustainable shallow water habitat is created by the project. All parameters listed above will be measured against current conditions to assess progress in meeting project goals. .
RRWD and State of Minnesota capital bonding
This multi-purpose project will partially restore a large drained lake, provide water level management capacity to substantially improve wildlife habitat conditions and provide flood damage reduction benefits. The project will also contribute to water quality improvements in the Roseau River.
Roseau Lake was drained in the early 1900s when the Roseau River was channelized and ditch systems were constructed to increase agricultural production in the watershed. Prior to drainage, Roseau Lake provided excellent fish and waterfowl habitat. After drainage, the lake basin was farmed and produced crops in drier times, but production was unreliable in most years. Over time, local landowners recognized that farming the lake bed would always be tenuous, and thus, large portions of the lake basin became part of the Roseau Lake Wildlife Management Area in the 1960s. Interest in a partial restoration of the lake grew in recent years because the DNR, watershed district, local governments, and citizens recognize that there are opportunities to develop a multipurpose project with significant wildlife habitat and flood damage reduction benefits (see attached citizen's advisory report).
Roseau Lake currently fills from overflow from the Roseau River. Habitat benefits for waterfowl are impressive when the basin is flooded. But the benefits are not sustainable because the lake often drains (i.e., via a county ditch) after breeding efforts of waterfowl have been initiated, thus stranding nesting birds. Conversely, flooding after nest initiation can claim many nests in some years. This project will build in the ability to retain water and/or flood the basin at key times of the year to attract more waterfowl and shorebirds and moderate water level fluctuations within the basin to optimize wildlife production.
In recognition of changes to the surrounding landscape that drainage for agriculture has caused in local hydrology, the DNR believes that a basin managed with seasonal water will benefit for wildlife while allowing flexibility to deal with ecological problems (e.g., invasive species) that may occur. This seasonal approach to water management is compatible with watershed district management for flood damage reduction.
The project has two primary purposes:
1) To improve the quantity and quality of wildlife habitat in and surrounding the Roseau Lake basin area. A key objective of the project is to provide migratory habitat (primarily abundant forage) for waterfowl and shorebirds in spring and fall and to improve the capacity of the basin to produce waterfowl.
2) To use the water storage capacity of the basin to reduce peak flows on the Roseau River downstream of the lake bed by 10% or more compared to current conditions as well as reduce the footprint of the 100-year floodplain.
To achieve wildlife habitat objectives, a system of levees and water control structures will be constructed to provide capacity to actively manage water levels in the basin. This infrastructure will allow wildlife managers to manage lake levels seasonally so that food and cover requirements of waterfowl will be met.
If easements are purchased with OHF monies, they will be permanent easements that require installation and maintenance of permanent vegetative cover that provides habitat appropriate for the area. These tracts are entirely within the basin, adjacent to existing WMA, and in key locations relative to project infrastructure (e.g., contain a portion of the planned levee for the project). 500 acres of private lands are targeted for acquisition/easement by the watershed district. These acres tend to occur on the periphery of the basin. Fee title acquisition of the parcels cited is desirable, but easements may need to be used if landowners would prefer not to sell their land. If easements are used, they will be flowage easements held by the watershed district. Non-OHF funds will be used for flowage easements.
Operation of the project will be governed by a mutually-agreed upon plan between the DNR & watershed district. The plan will specify seasonal water levels that will increase waterfowl and shorebird use of the basin. Spring and fall water levels will be managed to create an abundance of shallow water which provides abundant forage for migratory waterfowl and shorebirds. In addition, shallow water management during summer will enhance the relative value of surrounding grass cover for nesting and provide brood-rearing cover for waterfowl and other waterbirds. Benefits to aquatic invertebrates, amphibians, reptiles, and aquatic mammals will accrue whenever water is present. Improvements in water quality, hydrologic conditions, and the riparian habitat corridor along the Roseau River will result in better fish habitat.
The wildlife benefits of the project will be achieved in a number of ways. First, water level management in the basin will be timed to coincide with life history requirements of waterfowl and shorebirds. For instance, the basin will be flooded with water from the Roseau River during spring and fall migration to provide shallow foraging habitat for waterfowl and shorebirds. Known arrival dates of various species will inform the operation plan of when to flood the basin. Similarly, invertebrate-rich shallow water for waterfowl brood-rearing will be provided adjacent to dense nesting cover during summer. Second, by reducing the flood peak downstream of the project, habitat improvements for plants and animals in the Big Swamp will be achieved.
Project infrastructure will also provide the capability to manipulate timing of flood flows on the river to optimize water storage capacity of the basin for flood damage reduction. Currently, Roseau Lake floods early in a given event such that flood storage is unavailable when the flood peak passes through the area. Flood damage reduction benefits will be achieved by altering the timing of water storage in the lake basin so available storage is more effectively used to reduce peak flows downstream. Habitat downstream of the project in the Big Swamp has been degraded due to excessive depths, duration, and frequency of flooding. Thus, a reduction in peak flows downstream provides additional natural resources benefits that include improved hydrologic conditions in the Roseau River which, in turn, will contribute to improved habitat. Rare plant communities in the Big Swamp will also benefit from a reduction in peak flows. Siting of project infrastructure will be guided by water management considerations/constraints as well as the presence of cultural resources and existing wetlands (all of which will require professional services to locate and delineate).