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a. Project Overview: Lake Red Rock was constructed from 1960 to 1969 as a flood control reservoir on the Des Moines River. Other authorized purposes include fish and wildlife management and recreation. The normal, conservation pool of Lake Red Rock is elevation 742, providing a lake surface acreage of 15,200. At full flood pool the lake surface exceeds 65,000 acres. The project encompasses over 50,000 acres of fee land and over 25,000 acres of flowage easement, making Lake Red Rock the largest holding of public land and lake in Iowa. The watershed of Lake Red Rock is 12,323 square miles, which is about 25% of the surface of Iowa, plus a small portion of southwest Minnesota.

Lake Red Rock has a similar species mix expected in Midwest natural or artificial lakes. Crappie, Largemouth Bass, Channel Catfish and White Bass are the most sought-after fish species in the Lake. It is not uncommon to catch 12-15 inch, 15-20 inch Largemouth, 15-18 inch White Bass or a 5-10 pound Channel Catfish in the lake. Anglers report that fish are attracted to structure along the shoreline and popular bridge crossings, the marina and the outflow from Robert’s Creek sub-impoundment. One of the priorities of this project is to provide more permanent habitat to disperse fish and fishermen more uniformly across the lake.

Once the dam began operations natural lake bottom structure has predictably degraded or disappeared due to large lake level fluctuations and lack of emergent vegetation communities. Simultaneously, of the most serious problems plaguing Lake Red Rock has been sedimentation. The lake bottom is nearly featureless due to these influences. The primary goal and objective of this proposal is to improve the fisheries habitat for multiple benefits using Mossback structures.

The specific acres and location is part of the long-range planning for the reservoir by the Corps of Engineers, Iowa DNR and Red Rock Lake Association. The plan is in a conceptual, developmental stage at this time; however, the Reservoir Fish Habitat Management Manual (Friends of Reservoirs), along with professional guidance by Iowa DNR fisheries biologist, angler participation and others will shape the plan to make it concise, comprehensive, and doable. The Corps of Engineers is in the process of remapping the lake bottom by way of a bathymetric survey. This should be completed by September 1, 2022 and was last conducted in 2011 as a routine exercise to quantify the amount of sedimentation in the reservoir.
Numerous watershed initiatives funded by the State of Iowa, USDA Natural Resources Conservation Service, the City of Des Moines and numerous NGO partners are underway in the Raccoon and Des Moines Watersheds.

Fully understanding of the biology and management strategies of Lake Red Rock is not possible without knowing about Red Rock’s involvement in the Sustainable Rivers Program (SRP). SRP is a nationwide partnership, initially organized the Corps of Engineers and The Nature Conservancy, to find ways to operate dams and other Corps owned and operated infrastructure in more environmentally friendly ways. See https://www.mvr.usace.army.mil/Missions/Environmental-Stewardship/Sustainable-Rivers/Des-Moines-River-SRP/

In 2016 Red Rock hosted a two-day environmental flow and pool management workshop with biologists, stakeholders and other scientific experts to learn what primary ecological concerns they had with the Des Moines River. Eight recommendations were realized from the workshop: Reduce nitrate levels, mussel mortality, sturgeon mortality (downstream), gas bubble trauma, downstream bank erosion; and improve conditions for migrating water birds, conditions for reptiles and amphibians, and conditions for downstream river recreation. These recommendations were influential in a revised lake regulation manual.

To accommodate the above-mentioned recommendations and other environmental conditions, a conservation band was incorporated into the regulation manual to enable the Corps to adjust pool levels to benefit a biological purpose either in the lake or for downstream conditions. The Corps developed an Adaptive Management and Monitoring Plan (AMMP), along with assistance from partners and stakeholders. In-lake water level management strategies and environmental flows downstream of the dam are specific elements of the AMMP that seek to support fish and mussel life histories. Many successful environmental flows and research studies have sprung from that plan and is regarded as a model for dams and reservoirs across the country. Currently, Lake Red Rock is one of four designated SRP Science project sites. SRP is funding the Iowa State University Cooperative Research Unit to conduct a 2-year research program associated with the fisheries, mussels, and their habitat in the Des Moines River, with the goal of evaluating how fisheries and mussel resources respond to the operations of Red Rock Dam. This data will be utilized in the adaptive management of dam operations and continued refinement of the Des Moines River Adaptive Management and Monitoring Plan.

Ongoing SRP efforts also work to find solutions that address nutrification and other water quality concerns within the Des Moines River. Early research on the denitrification ability of Lake Red Rock from 1974-2019 has concluded that the reservoir has reduced nitrates 12% from incoming flow to its release through the dam. Through a contract with the University of Iowa, Hydroscience & Engineering, we hope to further understand this process and how pool management may influence denitrification. In a complimentary effort, the Corps of Engineers has partnered with the Natural Resources Conservation Service to find ways to reduce nutrient inputs into the lake. Thirty-three watersheds encompassing Red Rock and Saylorville Lake (upstream from Red Rock, north of Des Moines) have been assessed to determine locations where soil conservation structures could exist, and opportunities for modifications to land use practices or soil conservation structures to reduce the nutrient and sediment input to the reservoirs. This information will be combined with the Agricultural Conservation Planning Framework, a software program that helps identify landscapes where improvements can be made. A Watershed Resilience Tool has been created to guide landowners through a process of education and geo-spatial analysis of lands to identify and prioritize soil health and preserving practices. See https://storymaps.arcgis.com/collections/314cc43943f94732ab1fa5ad7cecde40. A kick-off workshop with land managers of federal property in the Saylorville and Red Rock watershed is being planned for spring 2022.

Lake rim stabilization by rip rap revetment along some of the lakes most eroded shoreline is being planned for the current fiscal year. This bank stabilization will occur adjacent to one of the proposed fish habitat structures as part of this project.

Fishing is an outstanding recreational pursuit and a boon to the local economy. The Iowa Lakes Valuation Project indicated that Iowans made an estimated 341,561 household trips to Lake Red Rock to fish in 2014, traveling an average distance of 52.3 miles (Joen et al2016). Another study by the American Sport Fishing Association in 2020 outlined the economic benefits for the four congressional districts in Iowa. In the two congressional districts (2 &3) encompassing the Lake Red Rock area anglers created $179.9 million in retail sales and 1890 jobs (American Sport Fishing Association 2021). Thus, investment in the reservoir to improve environmental conditions therein, or for the fishery is money well-spent.

1) Improve Lake Red Rock Fisheries Habitat by assessing existing conditions, identifying suitable locations to improve habitat, establish habitat plan, and execute plan. Plan as conceived at this writing includes approximately 125 Mossback structures to be placed at select locations to maximize benefit. The state and federal government are spending tens of millions to address sediment and nutrients entering Lake Red Rock and we feel that limited Fish Habitat Partnership funding is best used to address limited littoral structure in the lake. See Figure
2) Raise awareness of anglers and general population about need for fisheries habitat improvement, solutions, water quality, and environmental conditions. Provide opportunities to address these issues through research and with people of all ages.
3) Educate anglers and general population about reservoir problems or opportunities, issues of concern, solutions and specific projects accomplished, to be accomplished that primarily involve Objectives 1 and 2.
g. Start date: 1 April 2023 Stop date: 30 June 2025
h. Amount of grant and estimated total cost: $ _______________________
*See also Section D.
i. Project partners and cash/in-kind contributors: Red Rock Lake Association, Iowa Department of Natural Resources, Vermeer Charitable Foundation, Pella Rollscreen Foundation, Central College, Numerous angler volunteers (unaffiliated with organizations). *Need letter of support from IDNR

The RRLA and many additional volunteers will be used to help determine best placement of the structures. Bolstered by a new bathymetric survey (expected summer 2022), volunteers, DNR biologists and others will help determine placement and spacing to maximize benefit. Lake Red Rock Environmental Stewardship/Sustainable Rivers Program staff are hosting a Fish Habitat Workshop in Spring of 2022 to discuss this project and others. The exact number of structures will depend upon funding; spacing will be done according to best management practices for the respective structures placed. Water quality monitoring is performed year-round and de-nitrification studies will be ongoing through 2023. DNR monitoring and data analysis will determine the catch rates, population trends, etc.

There are many metrics that will be monitored because of the AMMP and fish habitat improvements. The Iowa DNR will monitor new fish structure success and utilization by fish through sonar monitoring and electrofishing This monitoring will be performed for two years, plus data analysis. In addition, the Lake Red Rock Park Rangers occasionally query angler success during patrol at boat ramps or on the water. Current and new SRP initiatives will be monitored to gauge the state of the reservoir water quality, denitrification, recreational use, etc.

Lake Red Rock has a very active education and interpretive program. Press releases will be created and disseminated about the grant award from Friends of Reservoirs. In addition to the volunteers associated with the RRLA, Lake Red Rock (Corps) has an active and enthusiastic group of anglers and other volunteers that have assisted with fisheries habitat improvement in the past and will be recruited to help with this effort. Youth groups, whose membership is variable and fleeting with their transitory condition, will be recruited as well. Red Rock does this routinely. Red Rock will post news and activities associated with this project on their social media outlets (e.g., Facebook) and through displays in the Visitor Center and campground bulletin boards. A Fish Habitat & Management Workshop with angler and reservoir partners and enthusiasts is planned for March 2022.