Preface. City of Chardon City of Wickliffe Chardon Township Munson Township Russell Township South Russell Village

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1 Conceptual Mitigation Plan for Riparian Zone Restoration Project # Presented to: Chagrin River Watershed Partners, Inc. P.O. Box 229 Willoughby Hills, Ohio Prepared by: EnviroScience, Inc., 3781 Darrow Road, Stow, Ohio (800) December, 2003

2 Preface Funding for this project has been provided by a grant from the Coastal Zone Management Act, administered by the Office of Ocean and Coastal Resource Management, National Oceanic and Atmospheric Administration through the Ohio Coastal Management Program, administered by the Ohio Department of Natural Resources, Office of Coastal Management. EnviroScience expresses sincere appreciation to Ms. Kyle Dreyfuss-Wells and Ms. Amy Holtshouse of Chagrin River Watershed Partners, Inc. for selecting our firm to perform this exciting study, and supporting us by investing hours of research, coordination, and fieldwork. Special thanks are also extended to the numerous property owners who allowed us to access and survey their streams, as well as the following municipalities that were involved in the study: City of Chardon City of Wickliffe Chardon Township Munson Township Russell Township South Russell Village

3 Executive Summary The proposed projects are intended to serve as part or all of mitigation requirements for stream impacts associated with separate projects within the Chagrin River watershed. The purpose of the conceptual plan is intended to guide applicants and facilitate obtaining approval from regulatory agencies to proceed. Although, this conceptual plan provides a direction and conceptual approach based on initial site information, further evaluation and analysis of the project area will be necessary to ensure project success. This conceptual plan is a generalized plan designed to reestablished or enhance riparian areas of six sites. This plan could also potentially serve as a restoration plan for other applicable sites within the watershed, which were previously unknown or unavailable. The goal of each project is to restore or enhance riparian areas within the Chagrin River watershed utilizing only native vegetation in a natural planting scheme to promote site aesthetics as well as water quality functionality. Furthermore, project goals should attempt to maximize riparian planting areas while simultaneously balancing the needs of surrounding land-use, recreational opportunities and the interests of stakeholders. The mitigation plan details a three-zone riparian buffer approach (USDA 1997). This system is designed to be flexible, to meet the needs of landowners while providing water quality benefits. The plan also provides methods for planting in areas where a three-zone approach may not be feasible due to individual project constraints. Lists of suggested native tree, shrub and seed mixes are provided as well as cost estimates for purchasing and installation. Information regarding timing and plan implementation are addressed. Details of planting densities and a representative natural random planting scheme are also provided. Estimate project costs range from approximately $8,000 to $130,000. Costs do not include annual monitoring for five years to determine survivability and growth, which is approximately $16,000. Monitoring estimates are based on an annual site visit for one individual for 4 hrs. at $50.00/hr to collect field data. This cost also includes annual report preparation of one week at a rate of $75.00/hr.

4 Conceptual Mitigation Plan for Riparian Buffer Enhancement Site Overview The proposed project is intended to serve as part or all of mitigation requirements for stream impacts associated with another project within the Chagrin River watershed. The purpose of the conceptual plan is intended to guide applicants and facilitate obtaining approval from regulatory agencies to proceed. Although, this conceptual plan provides a direction and conceptual approach based on initial site information, further evaluation and analysis of the project area will be necessary to ensure project success. This conceptual mitigation plan is a generalized plan designed to reestablished or enhance riparian areas of six sites (Table 1) within the Chagrin river watershed. This plan could also potentially serve as a mitigation plan for additional sites within the watershed, which were previously unknown or unavailable. Generalized locations of potential mitigation sites are located on Map 1; Appendix A. Representative photos of each potential site are provided in Appendix B, followed by a brief site description, Chagrin River Watershed Partners, Inc. (CRWP) should be contacted for further details. Table 1. Potential Mitigation Sites Site Municipality Estimated length (l.f.) 9 Russell Chardon Russell Wickliffe Munson 1, Russell 1,080 The riparian zone or riparian buffer is the area of trees, shrubs and herbaceous vegetation existing along streams, rivers and drainage ways. This vegetation protects open water from runoff and adjacent land uses. These buffer areas reduce soil loss, stabilize banks, absorb nutrient runoff, moderate temperatures and provide habitat for insects and terrestrial wildlife. Through these functions riparian areas provide flood control, erosion control and water quality protection. Without riparian buffers, streams become susceptible to bank erosion and warmer water temperatures which decreases biological and water quality potential. As a State Scenic River, the Chagrin River relies heavily on the quality of its contributing waters. Riparian buffers are vital for good water quality. Many impacts to these areas can be reversed with stewardship, change of management practice or the re-construction of historical buffers. Although impacts from these potential mitigation areas may be offset by the cumulative inputs of the entire Chagrin River watershed, the ability and opportunity to restore even a small area should be held in high priority. These areas will no longer become a negative point source but rather add to the positive water quality source for the watershed. EnviroScience Inc. Chagrin River Watershed Partners Page 4

5 Project Goal The goal of the projects are the permanent restoration or enhancement of the riparian areas within the Chagrin River watershed utilizing only native species in a natural planting scheme to promote site aesthetics as well as functionality. Furthermore, project goals should attempt to maximize riparian plantings while simultaneously balancing the needs of surrounding land-use, recreational opportunity and the interests of all stakeholders. Benefits There are numerous project benefits associated with this particular type of restoration. They are: C Temperature moderation C Decreased bank erosion C Decreased downstream sedimentation C Preservation of existing floodplains C Increased aquatic and terrestrial habitat C Increased bank stability C Creation of educational and interactive examples of riparian function C Improved aesthetic conditions C Nutrient runoff absorption Restoration Approach Prior to any restoration effort, it is recommended to establish communication with all oversight agencies and shareholders to formally address restoration goals. This facilitates focused, creative, and cost effective problem solving throughout the entire restoration process. Conservation easements must be established on the project areas, therefore, a willing easement holder must be located. Organizations that may be willing to accept an easement include Chagrin River Land Conservancy, the county Natural Resource Conservation Service, Soil and Water Conservation Districts, park districts and conservation groups. A common model for riparian zone creation is the three-zone approach (USDA 1997). This system is designed to be flexible to meet the needs of adjacent landowners while providing water quality benefits. While the three-zone approach may not be applicable to every project it provides a good example of species planting schemes. Zone 1 is a ft area closest to the waterway. It should be planted primarily with faster growing trees to quickly reduce soil erosion, nutrient run-off and provide shade and temperature moderation. If feasible and practical, willow cuttings should also be added to the stream banks at a spacing of 1/3 l.f to provide rapid bank stabilization. Zone 2 is located immediately outside of Zone 1 and is typically planted with slower growing hardwood trees and shrubs. This zone can vary depending on the particular project site but is typically ft wide. Zone 3 is an area of grass and forb species, which acts as an initial filter and disperses water flow to minimize erosion. This area is generally ft in width (Figure 1). Table 3 provides a list of suggested native grass and forb EnviroScience Inc. Chagrin River Watershed Partners Page 5

6 species suited to each zone. Due to the diversity of native seed mixes available on the market a specific mix was not suggested. Consulting landscape organizations are able to match appropriate seed mixes for each site and specific planting goal. Figure 1. Three-zone Riparian Buffer Approach Table 2. Materials and Labor Cost Table for Three-Zone Approach (Costs provided by Vizmeg Landscape, Inc., Stow, OH 44224, ) Contact George Vizmeg Zone Item Suggested Composition Quantity/Unit Material Cost Labor Cost Total Cost/Acre 1 Trees 300/acre $ $ $ Black willow Tulip tree Sycamore (native) American basswood Cottonwood Shrubs willow (cuttings) 1/ 3 l.f $5.00 installed variable 2 Trees 300/acre $ $ $ Green/white ash Red/sugar maple Red/White oak Shrubs 1200/acre $ $ $19, Choke cherry Witchhazel Serviceberry Viburnum Ironwood Dogwood Seed Upland native mix 10 lb/acre $86.70 $ * $ Seed Upland native mix 15 lb/acre $ $ * $ All Site preparation (as needed) Per acre $ installed $ * seeding cost includes installation of straw mat to aid in seed germination and protection EnviroScience Inc. Chagrin River Watershed Partners Page 6

7 Table 3. Suggested Native Grass and Forb Species Scientific Name Common Name Type Andropogon gerardii big bluestem grass grass Andropogon scoparius little bluestem grass grass Bouteloua curtipendula side-oats grama grass Elmus candensis Canada wild rye grass Panicum virgatum switch grass grass Sorghastrum nutans indian grass grass Lolium multiflorum annual rye grass Rudbecka hirta black-eyed susan forb Echinacea pupurea broad-leaved purple coneflower forb Each zone should be planted in a natural random planting scheme similar to the layout depicted in Figure 2. It is important to maintain appropriate spacing while avoiding repetitive patterns, rows or unnatural planting schemes. Trees should be planted at a density of approximately 300/acre while shrubs should be planted at a density of about 1200/acre. This equates to roughly one tree every 12 ft and one shrub every 6 ft. Seed mixes should be applied at approximately 15 pounds per acre. If the three-zone approach is not feasible due to width or land use constraints, then a mixed tree, shrub, and grass area may be designed. A mixture of woody and herbaceous vegetation should be planted in a random natural planting scheme (Figure 2). Plants should be a combination of Zone 1 and Zone 2 species. Planting densities should maintain appropriate spacing depending on species. Similar to the three-zone approach, perennial grasses and forb species should be planted along the upland margin to provide an initial filtration area and willow cuttings should be installed along the stream banks. A model ordinance for the establishment of riparian setbacks created by the CRWP provides proposed minimum riparian setback widths based on stream size. These minimum requirements as well as the three-zone approach should guide mitigation project design. A minimum of 120 ft setback should be placed on either side of streams draining greater than 20 sq. mi. up to 300 sq. mi. A minimum of 75 ft setback should be maintained on either side of streams draining between ½ sq. mi. and 20 sq. mi. Streams which have drainage areas less than ½ sq. mi., should have a minimum of 25 ft setback on either side. Setback widths should be extended to 100 year floodplain and include any adjacent wetlands. Riparian setbacks are a zoning tool which provide guidelines for minimal stream protection. Ultimately, riparian setbacks should satisfy project goals while maximizing planting areas. EnviroScience Inc. Chagrin River Watershed Partners Page 7

8 Figure 2. Natural Random Spacing Approach Project Design Considerations Erosion and Sediment Control A comprehensive storm water prevention plan would need to be developed based on sitespecific topography and planting design. The plan should focus on protecting disturbed soils from entering the waterways. Implementing excelsior matting and native seed mix application as soon as possible for each disturbed area will further minimize sediment runoff. Site Preparation Depending on local site conditions and final planting scheme, it may be necessary to perform site preparation procedures, such as removing existing or invasive vegetation through spraying or tilling. Efforts should be made to use existing vegetation if species are native to minimize soil disturbance and maintain existing stream stability. Otherwise vegetation should be removed in a step-wise fashion to coincide with the timing of planting events. Vegetation Regardless of the planting scheme designed for the site, it is important to match the habitat with the species and to use only native vegetation. The regional ecology has attained a natural equilibrium that can be put out of balance when alien species are introduced. Therefore, avoid exotic species in planting schemes. Exotic plants grow aggressively and generally out-compete native populations. EnviroScience Inc. Chagrin River Watershed Partners Page 8

9 Trees and shrubs should be planted in the spring between April 1 st and June 1 st and in the fall from October 1 st to November 31 st. Willow stakes or live cuttings should be installed while willows are dormant in late November through late March. August is the optimum time for applying native seeds mixes to areas such as Zone 3. Therefore, due to the varying optimum conditions for planting, several events may be necessary to complete a planting scheme. For example during a three-zone riparian approach project, it may be necessary to plant the Zone 3 filtration strip in August prior to planting Zones 1 and 2 in the fall. This would be followed by willow cutting installation in early spring. Maintenance Dead trees and shrubs should be replaced if they were in key positions or if there is less than 80% survival. Disturbed soils, provide an opportunity for exotic or invasive species to enter the project area. All invasive plants should be eradicated and these areas as well as other areas of bare ground should be reseeded. Plan Implementation These projects are intended to be completed as part of mitigation requirements for stream impacts from separate projects with the Chagrin River watershed. This section provides detail on necessary steps to implement the mitigation process. Conservation Easement A conservation easement must be established between the land owner(s) and a land conservancy or conservation organization for the project to be acceptable as mitigation. The easement places the responsibility of enforcing buffer restrictions on the second party, and may require an upfront or annual fee to cover the incurred expenses. Recommendations It is recommended to perform site visits of potential mitigation area prior to selection to document site-specific conditions such as access, surrounding land-use, and project scale. It would also provide opportunities to meet with stakeholders to address any concerns. In addition, observe any intact riparian areas adjacent to the project area to document native species as it may help guide planting schemes. Construction Feasibility Construction feasibility will vary for each site, but relatively good access exists at each of the proposed project areas. Most sites are accessible and in close proximity to roads or private drives. Appendix B provides a representative photo and brief description of the proposed project areas. Monitoring Although the conservation easement placed on the riparian corridor likely ensures the long-term success of the project, post-construction monitoring may be required by the regulatory agencies for duration of five years. Should this be the case, annual monitoring events will serve to document the growth and success of the restoration. This EnviroScience Inc. Chagrin River Watershed Partners Page 9

10 information is forwarded to the appropriate agencies in summary reports. Generally, benchmarks, established prior to the restoration, must be met by the end of the monitoring period. Survivability of riparian restoration projects should be no less than 80%. To determine survivability and growth, vegetative success will need to be monitored through sample plots or similar density estimate. EnviroScience recommends that permanent 25 X 25 ft sampling plots be established to provide a consistent annual monitoring site in which survivability would then be compared to original plant density. Permanent sample plots should be established in each zone if the three-zone approach is utilized or one plot for each plant community and on either side of the reach. For areas over 5 acres two or more plots should be established depending on total project area. If measured survivability is less than 80%, unless otherwise stated by regulatory agencies, additional plantings will be necessary. During the third year following construction, agencies will coordinate a site visit with the mitigation firm to evaluate the project and make recommendations to ensure its success. EnviroScience Inc. Chagrin River Watershed Partners Page 10

11 References United States Department of Agriculture (USDA) and Natural Resources Conservation Service (NRCS) Conservation Practice Job Sheet 391.

12 Appendix A: Maps

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14 Appendix B: Photos and Site Descriptions

15 Site 9. Russell Township This site is located in Russell Township near Music St. Deer Lake is a large man-made impoundment behind the dam observed in the photo. Riparian vegetation is needed below the dam. A shallow outflow stream and a nearby channelized tributary (just to the right of where the photo was taken) are in need of shading and stability provided by additional riparian vegetation. Project designs must take into account dam access. Estimated cost of this project is $8, for plant installation of a 25 ft setback totaling 0.3 acres of riparian zone. Site 11. City of Chardon This site is located in City of Chardon near Aurora Road (St. Rt 44). The reach flows along the entrance to an apartment complex and could benefit from riparian vegetation for bank stabilization and nutrient absorption. If continued, the existing riparian management strategy will continue to degrade this tributary. Project designs must consider an aesthetic approach combined with functional stabilizing vegetation. Furthermore there are multiple stakeholders associated with this project. Plans should highlight the many benefits of riparian zones, including a reduction in maintenance costs. Estimated cost of this project is $18,560 for plant installation of a 25 ft setback to either side, totaling 0.68 acres of riparian zone.

16 Site 20. Russell Township. This site is located in Russell Township near Fairmount Road. At the time of the survey it did not appear that the agricultural field had been utilized but it will likely be farmed in subsequent years. Regardless, a riparian buffer should be established to help filter sediment and nutrient runoff from the adjacent agricultural and residential land. Currently a small strip of vegetation exists along the stream, which likely includes existing native species worth incorporating into a planting scheme. Project designs must be sensitive to potential agricultural land-use. Estimate cost of this project is $12, for plant installation of a 25 ft setback to either side, totaling 0.45 acres of riparian zone. Site 52. City of Wickliffe. This site is located in Nehls Park near Buena Vista Dr. and Nehls Park Dr. in the City of Wickliffe. The headwaters of Gulley Brook flow through this community park. The existing management strategy does little to benefit the water quality or wildlife habitat. Project designs should be sensitive to the recreational use and incorporate an aesthetic component. Due to its location within a park, this may also serve as an excellent demonstration area for educating public on the importance of riparian buffers. Estimated cost of this project is $8, for plant installation of a 25 ft setback to either side, totaling 0.32 acres of riparian zone.

17 Site 57. Munson Township. This site is located near western entrance of the Sisters of Notre Dame Educational Center, and the intersection of Butternut and Wye roads in Munson Township. This project provides an excellent opportunity to restore a riparian zone to the headwaters of the Chagrin River. Currently, this reach is suffering from bank sloughing and erosion due to the lack of riparian vegetation. This project also has the potential to establish a relatively wide riparian zone; as much as 150 ft over the entire reach. Project designs should incorporate existing native species into the planting scheme. This project, along a State Scenic River, also provides an excellent public demonstration area for the importance of riparian buffers. Estimated cost of this project is $137, for plant installation of 150 ft setback on either side, totaling 7.2 acres of riparian zone. Estimates were based on the three-zone approach utilizing 25 ft, 100 ft and 25 ft for zones 1-3 respectively. Willow cuttings were also installed every 3 ft along both stream banks. The high cost estimate is primarily due to the shrub density in zone 2, therefore mitigating firms may want to investigate alternative densities or planting schemes to lower overall costs. Additional site delineation may also increase or decrease the planting area, which will be reflected in costs.

18 Site 61. Russell Township This site is located in Russell Township near County Line Road. This reach has suffered impacts from riparian removal. The surrounding land is recovering from past use, however, there is a small livestock operation to the west. Portions of the site already contain decent streamside vegetation such as willow but a majority of the site could benefit from supplemental plantings. This project provides an opportunity to established a wide riparian zone; as much as 150 ft on either side. This site may also provide the opportunity to establish floodplain wetland communities. Estimate cost of this project is $137, for plant installation of 150 ft setback on either side, totaling 7.2 acres of riparian zone. Estimates were based on the three-zone approach utilizing 25 ft, 100 ft and 25 ft for zones 1-3 respectively. Willow cuttings were also installed every 3 ft along both stream banks. The high cost estimate is primarily due to the shrub density in zone 2, therefore mitigating firms may want to investigate alternative densities or planting schemes to lower overall costs. Additional site delineation may also increase or decrease the planting area, which will be reflected in costs.