FW-004-25 – FILO – Big Rivers Wetland |
FW-004-25 – FILO – Big Rivers Wetland
Estimate:
$1,735,300.00
Estimated Length of Project:
September 1, 2025 (Substantial Completion) + October 1, 2025 (Final Completion)
The project will re-establish a stable and self-sustaining complex of intermittent streams and forested wetland within the project site. Two degraded intermittent streams, totaling approximately 3,715 linear feet in length, will be re-established with standard construction techniques to build streams that exhibit streambank and bed stability, increased habitat for aquatic organisms, and minimal floodplain erosion. The re-established streams will be constructed with appropriate meandering pattern, channel dimensions, and in-stream structures, and will increase hydrology in the adjacent wetland complex. Re-established Intermittent Stream 1 requires installation of an arch-shaped CMP culvert for crossing by the proposed 2,675 linear feet of gravel access roadway, also to be constructed by the project. A concrete low water crossing and dilapidated bridge deck are present on existing Intermittent Stream 2 and will be removed by the project. Approximately 1,550 linear feet of stone bank protection will be constructed on the adjacent perennial stream that receives the drainage from Intermittent Streams 1 and 2 via an existing concrete box culvert.
Earthwork to modify site topography will promote re-establishment of 40.6 acres of wetland. Grading will be used to undo the anthropogenic drainage modifications made to the site for agriculture, including eliminating or minimizing existing incised ephemeral and intermittent streams, surface drainage furrows, and subsurface drainage tiles. Culvert pipes with risers will be installed in the gravel access roadway to allow surface drainage to enter the re-established wetland. Specific subsurface areas will require installation of clay/clayey soils in compacted lifts to slow subsurface drainage; any encountered drainage tiles will be made ineffective.
Coir erosion control blanket will be installed along re-established intermittent streambanks and areas of stone bank protection construction. A seed mix will be installed throughout the riparian corridor and other non-wetland areas of disturbance and mulched with straw. A second wetland groundcover seed mix will be installed in the disturbed wetland re-establishment areas and mulched with straw. Ground preparation will be performed to support additional seeding, live staking, and tree planting by Others under a separate Contract.
Project Location: