Cedar Niles Future Park Site Wetland #1

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Belinda Fleming
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1 Date: October 20, 2014 Site: Landowner: Johnson County Parks Designer: Thomas R. Biebighauser Individuals Present: Thomas R. Biebighauser, Dr. Eliodora Chamberlain (US EPA), Jason Daniels (US EPA), Jeannette Schafer (US EPA), Bill Maasen (JCPRD), Monte Fiegel (JCPRD), Matthew Garrett (JCPRD), Cliff Middleton (JCPRD), Drew (JCPRD) Purpose of Project: 1. Implement a portion of the Master Plan for the future park by restoring naturally appearing and functioning wetlands only 1-mile away from the Ernie Miller Nature Center 2. Increase opportunities for the public to view wildlife 3. Enhance the beauty of the park 4. Provide habitat for amphibians, shorebirds, waterfowl, pheasants, pollinators, butterflies, and dragonflies. The wetland may be used by cricket frogs, narrow mouth toads, and tiger salamanders 5. Clean run-off from agricultural fields and future park developments 6. Reduce mosquito numbers with healthy wetlands that contain salamanders and dragonflies 7. Reduce flooding GPS coordinates (center of proposed wetland): 10 S / Percent slope: 0.5 percent, 1-foot change in elevation from upper to lower edge of proposed wetland Existing land use: A farm field that is being cut for hay Hydric soil present: No, the area is not an existing wetland Hydric plants present: None. The area is not a wetland. Groundwater elevation: Not found. Soil auger used by hand to drill hole to rock Soil texture: 0-15 inches topsoil, inches silt-clay (3-inch long thin ribbon), 48-inches + limestone gravel. A nearby exposed bank on Cedar Creek shows that the silt-clay may extend from 4 to 7-feet down. A gravel layer from 1-2 feet thick is found below the silt-clay. Bedrock was not observed. Deep test holes dug by using an excavator are needed to determine the elevation of bedrock. Evidence of historic drainage: Yes. The field was historically drained using a series of ditches. Runoff from tributaries and the hillside is diverted to either side of the field in constructed, straight ditches. Runoff is prevented from flowing over the field by a deep ditch along the upper side of the road. Cedar Creek appears to have been straightened and cleaned of large woody debris. The stream channel is now acting like a drainage ditch to dry the large field where the wetland would be built. Evidence of Cultural Resources: None found, the area has been cultivated for years Construction fill present? Rock may have been used to fill the wetland or make a drain Size of project: An ephemeral wetland can be made with a natural oxbow shape that is approximately 53-feet wide x 130-feet long (6,890 ft²), wet-meadow wetlands can be made surrounding the ephemeral wetland. How marked on the ground: A steel fence post was driven in the center of the area. Pink ribbons attached to vegetation mark the approximate perimeter of the wetland that could be built. Does a stream or ditch enter the area? None Are head-cuts located uphill or downhill from the marked area? No Description of project: A naturally appearing and functioning wetland may be built from a shallow depression within a large hayfield near Cedar Creek in Johnson County. The shallow depression may have been a wetland prior to 1

2 farming operations. The vegetation on the site is dominated by nonnative KY31 fescue. Rock may have been buried in the depression to facilitate drainage. The wetland would be built with features that provide habitat for a diversity of wildlife species. The wetland would be supplied naturally with water from the surrounding field. The stream would not be diverted to fill the wetland, nor would pumps be used to fill the wetland. The wetland can be expected to support a diversity of flowering plants, benefitting pollinators while adding beauty to the landscape. A floodplain permit may be needed for construction. Recommended actions: 1. Build an emergent wetland within the marked perimeter that is deepest in the center, with gradual (5-percent average) inside and outside slopes. The wetland should appear natural, have an irregular shape, with a maximum depth of 30-inches. Building a deeper wetland may result in perennial water, supporting unwanted fish and bullfrogs. 2. Avoid using a drainpipe or water control structure. This will reduce the need for future maintenance. 3. Remove and save the topsoil from within the marked perimeter. Later spread this topsoil in and around the finished wetland. The topsoil should not be compacted, and should be spread using the rough and loosen technique. 4. A deep test hole should be dug after the topsoil is removed. Its purpose would be to determine the elevation of bedrock, and if the bedrock can be a barrier to water soaking into the ground. If bedrock is found near the surface, and this bedrock is not permeable, then: 5. A core trench and groundwater dam should be used to build the wetland. The core trench must be dug through all subsurface permeable layers, and be based on a low permeable layer of soil, or on bedrock. The core trench should be located around the lower 2/3 perimeter of the planned wetland. Soil that is high in clay should be placed in the core trench, and compacted in layers to prevent water from leaking out of the wetland. If a subsurface impermeable layer is not found, then: 6. The wetland should be built using the compacted clay liner technique. This involves building the wetland so that the entire basin contains a layer of compacted clay that is at least 24-inches thick. The wetland is built by removing and saving the clay from within the marked area, removing and wasting gravel to form a basin 24-inches deeper than the planned depth of the wetland, and then spreading 6-inch layers of clay in the basin, with each layer being compacted until the clay is 24- inches or thicker in the basin. Topsoil can be spread loosely over the compacted clay. 7. The contractor should be prepared to haul water to the site to facilitate the compaction of soils that are high in clay. One may also need to mix wet clay with drier clay to obtain suitable moisture for compaction. Compaction will be tested periodically by using a penetrometer that Tom Biebighauser will provide. 8. An above ground dam would not be built to restore the wetland. The wetland would be a naturally appearing shallow depression that would not divert floodwater. 9. Excess soil would generally be spread uphill from the wetland being built by using a dozer or excavator. 10. Excess soil that is removed would be placed so that it does not erode. Efforts would be made to spread this soil so that it becomes wet-meadow wetland. 11. A wide spillway would be created over slopes less than 1-percent to prevent erosion, and to make wet-meadow wetlands. Water would flow from the spillway in a sheet-like pattern. It should not be necessary to place rock on the spillway. 12. The soil in and around the wetland would be shaped to form ridges, pits, mounds, and shallow scrapes to improve plant and animal habitat. 13. Large woody debris and rocks would be placed in the restored wetland to provide birds with perches and turtles with basking sites. 14. No roads would be built to restore the wetland. 2

3 15. Excess soil would not be moved off-site with dump trucks. 16. A professional contractor with wetland construction experience and references should be contracted by the hour to complete the project. This will result in the best possible work at the lowest price. Tom Biebighauser is available to be on site supervising the construction of this wetland. Recommended Heavy Equipment: Excavator with operator 200-Series 148 HP minimum 47,000lbs minimum And Wheel loader with operator With rubber tires 170HP minimum 36,900lbs minimum or Backhoe Loader with Operator With rubber tires 90HP minimum 19,000lbs minimum The red circle shows the approximate location of 3

The red arrow shows the location of a buried gravel layer at Cedar Creek Budget Estimate: 1. Excavator: price per hour includes mobilization, 10-hours @ $160.00/hour = $1,600 2.

4 The red arrow shows the location of a buried gravel layer at Cedar Creek Budget Estimate: 1. Excavator: price per hour includes mobilization, $160.00/hour = $1, Compactor: (Front-end loader or large 4WD Backhoe loader with operator), price per hour includes mobilization: $120/hour = $1, Wheat or oak straw to spread for mulch: $6.00/bale = $90 4. Wheat to sow for erosion control, 1-50lb $20.00/bag = $20 5. Project coordination & implementation by Tom Biebighauser = 1 day (funded by the Association of State Wetland Managers) Estimated cost = $2,910 Please contact Tom Biebighauser if you have any questions about this project. The book by Tom Biebighauser Wetland Restoration and Construction A Technical Guide provides detailed information about planning and building wetlands similar to this one. Prepared by: Tom Biebighauser Wetland Ecologist & Wildlife Biologist 4

5 Wetland Restoration and Training LLC 3415 Sugar Loaf Mountain Road Morehead, KY Home phone: Cell Phone: Website: 5

Wetland Restoration Project Cedar Niles Future Park Site Johnson County Park & Recreation District

Wetland Restoration Project Cedar Niles Future Park Site Johnson County Park & Recreation District Wood Ducks Southern Leopard frog Thomas R. Biebighauser November 29, 2014 Introduction Opportunities for