With assistance from Clean Water Act Section 604b funding, Lamoille County Planning Commission (LCPC) has been working with several towns in their region to strengthen infrastructure and better prepare for future floods and conducted a mapping analysis to determine the percentage of river/road conflict in each town in Lamoille County. Based on this analysis, LCPC targeted two towns (Stowe and Belvidere) in which to identify areas where town highway infrastructure is highly susceptible to future flood-related catastrophic failure. LCPC performed a subsequent mapping analyses in Stowe and Belvidere to determine the total constraints for flood vulnerability to town road infrastructure. Town road segments were searched for various constraints including the following: within a 50 foot stream buffer, within the 100 year floodplain, within the river corridor, at an undersized bridge or culvert crossing, stream incision, and steep road slope. The segments were scored for total constraints to identify flood vulnerability sites.
LCPC also met with town officials in Belvidere and Stowe familiar with past flood/washout damage, to present the results of the map analysis and obtain their input on other sites that may be of priority in terms of flood protection. In spring 2016, LCPC visited sites with the most constraints. Based on recommendations from town officials, LCPC also visited some sites listed on FEMA damage reports and those that were indicated as a problem for flooding or fluvial erosion hazards according to town officials.
The Town of Belvidere had the highest river/road conflict, with 63% of town highway infrastructure in conflict with the North Branch of the Lamoille River and its tributaries.
In Stowe, 27% of town highway infrastructure is in conflict with surface waters. LCPC came up with a total of 12 sites in Belvidere and 14 in Stowe to prioritize in terms of flood vulnerability.
Through this project, LCPC has targeted areas to help Stowe and Belvidere prioritize future infrastructure projects to improve flood resiliency. Both towns are challenged in managing their town roads due to the amount of surface water in conflict with roads and structures. Proper sizing of road crossings and other river management strategies that work with the natural flow of rivers will help to avoid future damage to town infrastructure. Adhering to these strategies will help Belvidere and Stowe become more flood resilient in the future.