Lake and Stream Restoration Project

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1 Pre-project Fact Sheet May 2012 Toledo Botanical Garden (TBG) is a 60 acre public garden visited by more than 120,000 people annually. It is located in Toledo, Ohio in the Ottawa River watershed within the Maumee Area of Concern. Hill Ditch is a perennial stream that flows west to east through the center of the TBG. Crosby Lakes are two manmade lakes within TBG that were created through the installation of two dams in The initial constructed depths of the upper and lower lakes ranged from 6 to 15 feet. Over the 20 years since their construction, the lakes have trapped an estimated 28,000 cubic yards of sediment. Many of the areas in the upper lake have filled in to become islands where invasive plant species have established themselves. In the lower lake, many areas have filled in and the banks are eroding and slumping into the lake. In 2009 with a grant from the USDA Natural Resources Conservation Service, TBG had a conceptual design created to address these issues. Dam removal was determined to be essential and a stream restoration plan was prepared. With the conceptual design developed, TBG was successful in receiving an Ohio EPA 319(h) Nonpoint Source Pollution Control grant in 2011 to implement the Crosby Lakes and Hill Ditch Restoration Project. The objectives are to: Improve the biological & chemical water quality Restore a natural stream channel Expand and/or enhance wetlands Enhance portions of Crosby Lake Create a sustainable system All of these would need to be accomplished through a project that would: Adhere to the TBG Master Plan Educate the public on sustainable natural ecosystems Provide a place where people can interact directly with a high quality natural stream, wetlands, and a rejuvenated Crosby Lake Toledo Botanical Garden, Toledo, Ohio

2 Preliminary Restoration Plans The preliminary restoration plan was developed, proposing construction of a sinuous channel for Hill Ditch by creating a series of berms that partially isolate portions of the lower and upper ponds from the new stream channel. Rock riffles and fish habitat structures were proposed. In order to minimize sediment accumulation in the adjacent wetlands and the remaining lower pond, berms must be constructed high enough so that sediments carried by the stream do not spill over into the pond during high water events. The restoration plan also proposes reinforcing the berms with features, such as visitor accessible stone pathways, many species of densely planted native vegetation, and Bendway Weirs, which add structure and habitat to the stream and direct the fastest flows towards the middle of the new stream channel. By doing this, erosional forces along the outer bends of the new streambank will be minimized, stabilizing the position of the stream channel. This will help to achieve the overall goal of creating a stream channel that can provide a diversity of habitat for aquatic organisms while remaining stable over a very long period of time with minimal maintenance by TBG. The preliminary plan also calls for enhancing the adjacent areas in the upper pond by creating a series of high quality floating leaved, emergent and scrub/shrub wetland systems that contain native plants. In the lower pond, plans include adding a variety of depths for open water and interspersing them with stands of native floating leaved and emergent vegetation. TBG has enlisted a team of experts to assist them with this complex project. Before this project can be constructed it is necessary for TBG to have studies conducted, detailed plans and specifications drafted, and obtain the necessary permits. Construction of this project is expected from Fall 2012 through Spring Public Involvement Involvement of TBG members, neighbors, volunteers and staff is highly encouraged as the project moves forward. Public information sessions will be held to update the community on the plans and progress throughout the project. TBG would like to get people involved in this project whenever possible. This is being accomplished through: Harvesting and Planting Plants Site Visits and Tours Youth/Scout Programs and Camps Wetland and Stream Restoration Workshops Educational Signage and Brochures Volunteers will be needed to harvest local native plants. Want to Learn More? TBG would love to tell you more about this project and/or answer any questions you might have. Contact TBG at or visit their website at This product or publication was financed in part or totally through a grant from the State of Ohio Environmental Protection Agency and the United States Environmental Protection Agency, under the provisions of Section 319(h) of the Clean Water Act. The contents and views, including any opinions, findings, or conclusions or recommendations, contained in this product or publication are those of the authors and have not been subject to any State of Ohio Environmental Protection Agency or United States Environmental Protection Agency peer or administrative review and may not necessarily reflect the views of either Agency, and no official endorsement should be inferred.

3 Post-project Fact Sheet Fall 2014 Toledo Botanical Garden (TBG) is a 66 acre public garden visited by more than 180,000 people annually. It is located in Toledo, Ohio in the Ottawa River watershed within the Maumee Area of Concern. Hill Ditch is a perennial stream that flows west to east through the center of TBG. Crosby Lakes were created through the installation of two dams in In just over 20 years, the lakes accumulated sediment turning much of the pond areas into shallow pools lacking aquatic habitat, diversity and general health. TBG applied for and received an Ohio EPA 319(h) Nonpoint Source Pollution Control grant in October 2011 to implement the Crosby Lakes and Hill Ditch Restoration Project. The objectives were to: Improve the biological & chemical water quality Restore a natural stream channel Expand and/or enhance wetlands Enhance portions of Crosby Lake Create a sustainable system The objectives would need to be accomplished through a project that would: Educate the public on sustainable natural ecosystems Provide a place where people can interact directly with a high quality natural stream, wetlands, and a rejuvenated Crosby Lake Adhere to the TBG Master Plan The Big Picture This restoration project included the removal of the two dams to allow for the natural free flow of water through Hill Ditch. Removal of the dams meant that fish would again move throughout the watershed without being blocked by barriers. With this removal, fish can now move from Lake Erie through the Ottawa River, into Hill Ditch and further upstream to spawn in even smaller tributaries. To restore Hill Ditch to a free flowing stream it had to be separated from the man made Crosby Lakes. The shallow areas upstream of the wooden bridge were a part of the old smaller lake. These areas were restored to streamside wetlands and now provide storage for floodwaters during large storm events. In fact, the restoration work at TBG serves to lower the 100 year flood elevation upstream, a benefit to the community and environment. The new design provides many new opportunities and vistas for visitors in addition to the environmental benefits. Toledo Botanical Garden, Toledo, Ohio

4 Key Features The renovation and restoration of Hill Ditch and Crosby Lakes was undertaken in the Fall/Winter of 2012/13, so as to minimally impact the use of the gardens. The restoration work included several key features to enhance the Garden and increase access to the water while improving habitat and water quality. Wetlands [ ] Upstream of the Formal Garden and wooden bridge the smaller Crosby Lake area has been restored to wetlands with a stream running through them. The wetlands provide opportunities for rare species of plants and help to store excess storm water. This area can be viewed from a series of sandstone boulders that serve as access and observation for both the wetland and stream. Channel Bank Protection [ ] Upstream of the wooden bridge and in front of the Formal Garden are a series of boulders that were placed to create a new stream bank. This narrows the stream to a more natural size; helping to restore natural stream function. The area between the new bank and Formal Garden serve as a mini wetland, visually softening the steel sheet pile wall, providing an area for wetland flowers and plants and providing more flood water storage area. This area can also help to remove suspended sediment in floodwaters Bendway Weirs [ ] Along with the channel bank protection and throughout the stream you may see either large single stones jutting out in the water like fingers or further downstream similar objects are visible but composed of multiple smaller stone. These features help to direct the streams flow towards the center of the channel to reduce bank erosion. The bendway weirs are quite effective, though barely noticeable in most cases. Their effects can easily be seen even after a small storm. Rock Riffles [ ] All rivers, streams, and ditches flow downhill, but this change in elevation can be hard to see, especially in northwest Ohio. Once the dams were removed, the change in elevation had to be mediated to prevent erosion. Three rock riffles were built to help ease the elevation change downstream. The riffles are located roughly in the positions of the former dams with one in between. The riffles allow fish to easily move up and downstream. This movement was not possible when the dams were in place. The riffles have also added the sound and visual element of moving water to the garden, something many people enjoy. Stone Fish Ledges [F] These ledges can be seen just downstream of the wooden bridge and rock riffle. The large rocks overhang the water and provide an open space below them. Fish and other aquatic organisms can use these open areas as cover to protect themselves from predators above, such as Great Blue Heron often seen at TBG. Similar to an undercut stream bank in a natural stream, these ledges provide shade and cool water. This undercut bank and rock ledge offer the protection, but don t contribute to soil erosion. Crosby Lake [ ] The larger Crosby Lake was dredged and deepened to it s original designed depths. The eroded banks were re graded and vegetated to hold soil in place. Much of the lake has shallow areas along the edges where emergent plants such as lotus have been planted. Samples collected one year after the project are showing biological and habitat improvements. It will take a few years for nature to fully recover from the disturbance of construction, but early results are positive. Want to Learn More? TBG would love to tell you more about this project and/or answer any questions you might have. Contact TBG at or visit their website at N This product or publication was financed in part or totally through a grant from the State of Ohio Environmental Protection Agency and the United States Environmental Protection Agency, under the provisions of Section 319(h) of the Clean Water Act. The contents and views, including any opinions, findings, or conclusions or recommendations, contained in this product or publication are those of the authors and have not been subject to any State of Ohio Environmental Protection Agency or United States Environmental Protection Agency peer or administrative review and may not necessarily reflect the views of either Agency, and no official endorsement should be inferred.

5 Artist Village Storm Water Project Toledo Botanical Garden (TBG) is a 66-acre public garden visited by more than 180,000 people annually. It is located in Toledo, Ohio in the Ottawa River watershed within the Maumee Area of Concern. Featuring display gardens and relevant plant collections, the property also includes the newly restored Hill Ditch and revitalized Crosby Lake. In July of 2013 TBG was awarded a grant by the Ohio Environmental Protection Agency under the provisions of the Surface Water Improvement Fund and the US EPA Great Lakes Restoration Initiative for the Artists Village Storm Water Project. The project was concentrated in two areas: around the administration building and, the larger portion of the project in the Artists Village, (a grouping of ten small buildings that serve as home to several resident artist organizations.) The project achieved multiple goals: Significantly lessens the volume of storm water runoff entering the sewer system. Serves as an educational demonstration to the general public showing the value and relevance of water quality and the ability to reproduce aspects of this project on a small scale in residential environments. Additional benefits include increased visibility of the Artists Village to visitors through the use of a new entranceway, opportunities to better utilize the plaza area, and a heightened awareness of TBG s commitment to the environment. The objectives were to: Improve the biological & chemical water quality Create a sustainable system The objectives needed to be accomplished through a project that would: Educate the public on sustainable natural ecosystems Provide a place where people can interact directly with a high-quality natural system The Big Picture Post-Project Fact Sheet The bulk of the construction was accomplished in one month, with all deliverables achieved within six months. Hardscape was replaced in areas surrounding the Artists Village and a new entranceway was installed to encourage increased visitor traffic through the village and exposure to the storm water project demonstration area. The entire project cost approximately $100,000 ($48,675 from the EPA). Scope included installation of permeable paver systems in four defined areas and regrading of the main lawn area in the Artists Village. Two catch basins were raised and capped and a rain garden was installed. Storm water runoff has been reduced in a total area that is slightly less than half an acre. The success is ultimately measured by the reduced volume of storm water runoff entering the local water system running through the property known as Hill Ditch. Spring 2016 Toledo Botanical Garden, Toledo, Ohio

6 Key Features Area A Catch Basin 1 Area A is located around the administrative building. This area was re-graded and 700sf of vegetated infiltration area (VIA) was installed. 900sf of pavement was removed and replaced with 750sf of permeable pavers. Two of the four downspouts at the front of the building were redirected into the VIA and the other already fed into the existing VIA. Total impacted area for runoff that in Area A is 2,000sf. Area B Catch Basin 2 Area B is located within the Artists Village, directly across the parking lot from the administration building. In this area, 700sf of pavement was removed and replaced with 700sf of permeable pavers. The catch basin was raised to the new grade level and capped as it will no longer be required for storm water runoff. Three downspouts were redirected in this area to VIA. The total impacted area for runoff in Area B is 3,600sf. Area C Catch Basin 3 Area C is located within the Artists Village as well as adjacent to B. 1,200sf of pavement was removed and replaced with 700sf of permeable pavers. 500sf of VIA was installed, as well as a 200sf community demonstration rain garden. The area was excavated and re-graded to drain into the rain garden. This catch basin was raised to the new grade level and capped, as it is no longer required for storm water runoff. All six downspouts in this area now drain to the VIA and rain garden. The total area for runoff impacted in Area C is 7,900sf. Area D Catch Basin 4 Area D is located at the Northern end of the Artists Village and nearest to the main entrance of the Garden. 1,400sf of pavement were removed and replaced with 350sf of permeable paver. An additional 1,050sf of VIA was installed. Three downspouts drain to the newly installed VIA. Total area for runoff that is impacted in D is 4,000sf. The scope of the total project was greater than the funding available through the EPA. Therefore TBG provided in excess of $50,000 towards the completion of this project. The majority of staff costs, other materials and additional sub-contracting work were funded by TBG. Want to Learn More? TBG would love to tell you more about this project and/or answer any questions you might have. Contact TBG at or visit their website at This project was financed in part through a grant from the Ohio Environmental Protection Agency under the provisions of the Surface Water Improvement Fund and the US EPA Great Lakes Restoration Initiative. The contents and views, including any opinions, findings, or conclusions or recommendations, contained in the publication are those the authors and have not been subject to any Ohio Environmental Protection Agency peer or administrative review and may not necessarily reflect the views of Ohio Environmental Protection Agency and no official endorsement should be inferred.