Diamond Lake Management Plan Minneapolis Minnesota Healthy Lakes & Rivers Partnership Committee Friends of Diamond Lake & Minneapolis Park and Recreation Board October 2009 Management Plan for Diamond Lake Table of Contents SECTION 1. Introduction & History.……………………………… 1 1.1 Description and History………………………………………………………… 2 1.2 The Friends of Diamond Lake…………………………………………………… 3 1.3 Events In the Diamond Lake Watershed………………………………………… 5 SECTION 2. Visioning Session………………………….….….……… 7 SECTION 3. Prioritized Goals and Action Plans…….………….… 9 3.1 Group Process…………………………………………………………………… 9 3.2 Action Plans……………………………………………………………………… 10 SECTION 4. Technical Background……………………………..… 17 4.1 Physical Description of Diamond Lake…………………………………………… 17 4.2 Public Access………………………………………………………………………. 18 4.3 Managing Water Surface Use Conflicts……………………………………………. 19 4.4 Diamond Lake Watershed & Land Use…………………………………………… 20 4.5 Precipitation……………………………………………………………………… 22 4.6 Diamond Lake Water Levels………………………………………………….…… 23 4.7 Geology and Soils…………………………………………………………….…… 24 4.8 Diamond Lake’s Wetland Characteristics………………………………………… 25 4.9 Other Technical Data for Diamond Lake………………………………………… 29 4.10 Trophic State Index (TSI)………………………………………………………… 29 4.11 Comparison to Similar Waterbodies…………………………………………… 34 4.12 Diamond Lake Fishery……………………………………………………..…… 35 4.13 Wildlife at Diamond Lake………………………………………………………... 36 4.14 Aquatic Vegetation……………………………………………………………… 36 4.15 Invasive Exotic Aquatic and Wetland Plants…………………………………… 36 4.16 Emergent to Upland Plant Community Analysis………………………………… 37 4.17 MLCCS Land Cover Classifications & DNR Plant Community Descriptions…… 39 4.18 Previous Work & Recommendations for Restoration Activities……………… 40 SECTION 5. Reference……………………………………………… 41 5.1 References…………..………………………………………………………….… 41 5.2 Glossary…………………..…………………………………………………….… 43 5.3 Guide to Common Acronyms and Abbreviations………..………………………… 46 Appendix A. Bylaws of the Friends of Diamond Lake…………………………… 49 Appendix B. Soil Survey Unit Descriptions……………………………………….. 54 Appendix C. Aquatic Vegetation Surveys………………………………………… 58 Appendix D. 2009 MLCCS Field Survey Plant Lists……………………………… 64 SECTION 1. Introduction & History In January 2009, the Diamond Lake Association was invited to participate in the Initiative Foundation’s Healthy Lakes and Rivers Partnership program along with three other Lake Associations in the Minnehaha Creek Watershed District. Under the coordination of Eric Evenson (Minnehaha Creek Watershed District), Marian Bender and Eli Condon (Minnesota Waters), participating lake association representatives attended two days of training on strategic planning, communication, and nonprofit group leadership. Representatives of many state and local agencies, as well as nonprofit organizations also attended the training sessions in order to offer their assistance to each lake group in developing a strategic Lake Management Plan. The Diamond Lake Association was represented at the Healthy Lakes and Rivers training sessions by: members of the Friends of Diamond Lake Board (Sue Buetgen, Scott Foss, Stuart Goldstein, Dan Heine, Shelley Johnson, Mary Martini, Mary Moilanen, and Dave Oltmans), Angie Timmons and Melanie Countryman (Hale Page Diamond Lake Assoc.), Bob Lind (community), and Ken Oulman (Diamond Lake Lutheran Church). Following the training sessions, each Lake Association held an inclusive community planning/visioning session designed to identify key community concerns, assets, opportunities, and priorities, and began work on detailed action plans to implement tangible change on community priorities. The Friends of Diamond Lake held this planning session on March 24, 2009, with nearly 60 people in attendance. The Diamond Lake neighborhood is comprised of year round residents for whom this location is their primary home. Details of the public input received at this session are provided within this plan. In a follow up community session on April 28, 2009, priority objectives were identified which are included in section IV of this plan. This document is intended to create a record of historic and existing conditions and influences on Diamond Lake and to identify the goals of the Diamond Lake community. Ultimately it is meant to help prioritize goals and guide citizen action and engagement in the priority action areas. State agencies and local units of government also have a vital role and responsibility in managing surface waters and other natural resources but, above all else, this Lake Management Plan is intended to be an assessment of what we as citizens can influence, what our desired outcomes are, and how we will participate in preserving and protecting this valuable natural resource. This Lake Management Plan is also intended to be a “living document.” As newer or better information becomes available, as we accomplish our goals, or discover that alternate strategies are needed, it is our intent to update this plan so that it continues to serve as a useful guide to future leaders. In discussing lake management issues, it is impossible to avoid all scientific or technical terms. We have tried to express our goals, measures of success, and other themes as simply and clearly as possible but have included a glossary of common limnological terms at the end of the plan to assist the reader. Limnology is the study of lake conditions and behavior. Finally, we would like to thank the benefactors of the Healthy Lakes and Rivers Partnership program for the Minnehaha Creek Watershed District, including the Watershed District itself, the McKnight Foundation, Xcel Energy and the Laura Jane Musser Trust. Diamond Lake Management Plan, October 2009 Page 1 1.1 DESCRIPTION AND HISTORY Throughout this document the terms lake and wetland are used to describe Diamond Lake. The waterbody known as Diamond Lake is defined as a wetland by the state regulatory agencies and the Minneapolis Park and Recreation Board despite the commonly held perception of a lake. Regardless of which term is used the Friends of Diamond Lake are committed to preserving, protecting, and improving Diamond Lake and its surrounding ecosystem. What we label the waterbody is not the issue. What Diamond Lake is, and what it can be, are the important issues. Figure 1. Map of Diamond Lake based on 2006 aerial photography. Diamond Lake is located in south Minneapolis just to the northeast of the Interstate 35W and Highway 62 interchange. Diamond Lake Road runs along the north side of the lake and Portland Avenue on the east. The waterbody extends south to approximately 59th Street and nearly to Clinton Avenue to the west. Diamond Lake is surrounded by approximately 40 acres of parkland. Diamond Lake Management Plan, October 2009 Page 2 Today land surrounding Diamond Lake is almost completely urbanized but the lake was once part of an interconnected series of lakes and wetlands that drained to Minnehaha Creek. By 1913 Diamond Lake Road had been constructed between Diamond Lake and Pearl Lake. By 1916 Pearl Lake and the east arm of Diamond Lake had become marshes. During dry years Diamond Lake temporarily went dry. In 1937 Pearl Lake was filled with excess dirt from the municipal airport, the south end being built up higher than the north to accommodate baseball fields. At that time Diamond Lake had no open water and was filled with cattails. Development of the storm sewer system in 1940 with drainage going into Diamond Lake resulted in dramatic fluctuations of the water levels in the lake in 1941 and 1942. In 1942 a drain pipe was laid underground from the northeast corner of Diamond Lake to Minnehaha Creek to relieve the large water fluctuations. In 1991 The MPRB sought and received a permit from the MN Department of Natural Resourced to raise the level of the lake by setting a weir in the drain pipe between the lake and the creek. 1.2 THE FRIENDS OF DIAMOND LAKE Friends of Diamond Lake (FoDL) was formed as a non profit corporation on Feb 20, 2008 supported by a grant from the Minnehaha Creek Watershed District (MCWD) as part of its Watershed Association Initiative program. During a lunar eclipse seven committed citizens signed the Articles of Incorporation and Bylaws (Appendix A). The early roots of FoDL and efforts to preserve and protect Diamond Lake date back to the late 1970’s and the Diamond Lake Neighborhood Association(DLNA). Candi Storm, president of DLNA, saw Diamond Lake being used as a place for discarded tires, screen doors and other debris to be dumped and a body of water whose quality was suffering from urban street runoff as its source of water. Her efforts resulted in the formation of an Environment Committee and annual spring cleanup that has been going on for over thirty years and is now part of the Annual Earth Day event at Pearl Park. There were ongoing efforts in the 1980’s and 1990’s to protect and improve the lake including development of a draft management plan in 1981 by Mike Ryan, Environmental Education Coordinator for the MPRB. The plan was never adopted or implemented by the park board. In August of 1986 Hickock and Associates submitted a Sedimentation Study to the City of Minneapolis Department of Works, calculating the rate of sedimentation and reviewing five restoration techniques; chemical treatment, mechanical aeration, weed harvesting, construction of upstream sedimentation basins, and dredging. In 1989 as part of the city of Minneapolis’ efforts to strengthen neighborhoods, the Neighborhood Revitalization Program was created. The HPDL neighborhood was