Request of Proposals - Final Design Engineering Holmes Meadow Floodplain Restoration Johnson

In Partnership with the Lamoille County Planning Commission (LCPC), the Town of Johnson received a Flood Resilient Communities Fund Grant in Spring of 2021 funded by the Vermont Emergency Management to acquire a parcel in Johnson, and design, engineer, and construct an active floodplain restoration project on site. The final design will be informed by the local community vision and goals for the site. This proposed active floodplain restoration project is located at the 2.4-acre, town-owned parcel at the end of River Road West, Johnson, VT. This property, VT Route 15, and the Village of Johnson are highly susceptible to flooding. This river/road conflict area is a key location identified for floodplain restoration in the 2019 Lamoille River Flood Model. The floodplain restoration project will enhance floodplain access by removing a man-made berm, lower the floodplain, and create a riparian forest. The project will allow floodwaters to dissipate naturally into a vegetated area, improve

“hydraulic roughness,” and prevent the spread of invasive species. Increasing access to the floodplain will reduce future flooding and erosion along Route 15, in the Village of Johnson, and along the banks of the Lamoille River. This project expands upon previous hydraulic modeling efforts along the Lamoille River. The 2019 Lamoille River Flood Model identified where active floodplain restoration has the potential to reduce flood levels and flood water velocities in the Village of Johnson and on Route 15. Due to the Holmes Meadows’ critical location at a bend in the Lamoille Mainstem near the confluence with the Gihon River, floodplain restoration would reduce potential risks and damages from flooding and ice jamming by providing a location for the river to deposit ice and other debris outside of the river channel. This project will aid in reducing the flow of nutrients and sediment from flood waters to the Lamoille River by improving floodplain function and management, allowing floodwaters to access the floodplain and sediment to drop out onto the field during flooding events. The hydraulic modeling for the proposed active floodplain restoration demonstrates an existing berm blocks flood flows from reaching the floodplain until flood waters are higher than the 50-year flood. In addition to floodplain restoration and berm removal, the final design and engineering work will incorporate a vision for the site identified during community engagement meetings.