RIPTON — Middlebury and Ripton officials support further study of a $1.6-million plan to install a series of flood walls and culverts along Route 125 from Ripton to East Middlebury as a way of minimizing washouts and other damage from future flooding.
The plan in question is one of four potential flood mitigation solutions for the Route 125 corridor studied by consultants at the request of the Addison County Regional Planning Commission (ACRPC).
The most ambitious of those potential solutions called for realignment of Route 125 south to the old Center Turnpike/Old Town Road — an existing, little-traveled Class 4 roadway — in a manner that would bypass Ripton Village and allow the Middlebury River to migrate into its natural path and tributaries.
Amy Sheldon of East Middlebury’s Landslide Natural Resource Planning and Roy Schiff of South Burlington’s Milone & MacBroom explained their report this week to Ripton and Middlebury selectboards. The ACRPC commissioned the report in wake of substantial flooding of the Middlebury River in 2008, a pattern that consultants said has been getting more frequent during the past 20 years.
“(Route 125) has never been engineered properly to be close to a river,” Sheldon told Middlebury selectmen on Tuesday.
Route 125 between Ripton Village and Upper Plains Road in Middlebury has three sharp bends (Barney’s Curve, or Big Bend; Middle Bend; and Little Bend) that wash out about every 10 years during flash floods that frequently take place in this mountainous area, the study notes.
In August 2008 severe thunderstorms in the headwaters of the Middlebury River washed out portions of Route 125 and the Dugway Road. The damage and cleanup resulted in Route 125 being closed for roughly 10 days and the Dugway for much longer. An earlier event in June of that same year washed out the North Branch Road and kept it closed for several weeks until the box culvert at Danny Dragon Road was replaced.
Recurring damage, Sheldon explained, is associated with both erosion from the Middlebury River and poor roadway drainage. The river and its tributaries are trying to move larger amounts of water and sediment. As the waterway gets more constricted with rock and other debris, the velocity of rushing water will only get stronger and potentially make the next flood event more catastrophic, she said.
And there is a lot at stake whenever the Middlebury River floods. Several residences, municipal buildings and at least one church are vulnerable to cresting floodwaters in Ripton Village.
The town of Ripton, thanks to some federal and state funding, is currently installing riprap and other safeguards within the banks of the river to try and blunt the effects of future flooding.
At the same time, work crews have been repaving Route 125 from East Middlebury to the Middlebury College Snow Bowl in Hancock, a project costing several million dollars in state funds.
Those two substantial capital investments could be in jeopardy barring a long-term solution to better contain the Middlebury River, officials said. And more than $1.2 million has been invested in flood-related repairs along Route 125 just in the past 12 years, according to the study.
Schiff noted that it collectively costs travelers $40,000 — just in lost time and productivity — for each day Route 125 is closed after floods. Route 125 serves around 2,300 vehicles daily, according to Schiff.
“It’s quite a capital expense to keeping that road open,” Schiff said.
With that in mind, Sheldon and Schiff looked at four possibilities for stemming floodwaters in the Route 125 corridor. They include:
• Installing flood walls along the edge of the roadway on frequent washout areas (Little Bend, Middle Bend and Big Bend). In addition to these three wall segments, seven culverts would be installed to enlarge what consultants said are “severely undersized” cross culverts.
Ditch network upgrades would also be required to promote drainage network into the proposed culverts and at estimated cost of $1.6 million.
• Introducing bridges, rather than floodwalls, over the three Route 125 bends identified in the study. The bridge abutments would be tied into bedrock protruding along the valley wall. The bridges would provide more space for the river to flow down the valley, and provide the maximum opportunity for the tributaries to get water, sediment, and debris under Route 125 to the Middlebury River, according to the study. That estimated cost would be $6 million.
• Re-aligning Route 125 to the Center Turnpike/Old Town Road, which is a pre-existing, parallel-running roadway. This scenario would divert primary traffic away from Route 125 and would allow the river to branch into its natural channels and floodplain, according to Sheldon. The 2.6-mile roadway would be designed with proper drainage and crossings, with one new bridge and seven culverts required — in addition to the new road base and travel surface. That estimated cost is $6,56 million.
Sheldon stressed that while primary traffic would be taken off Route 125, the town would still need to take steps to keep the river from skipping its banks in the village area.
• A variation of the Route 125 realignment to Center Turnpike/Old Town Road that would allow the roadway to rejoin Route 125 west of Ripton Village. This would ensure that primary traffic would continue to pass through the village. The estimated cost would be $5.59 million.
Sheldon and Schiff presented the $1.6 million floodwall and culvert plan as the most realistic to fund and implement. But they stressed that Ripton and Middlebury officials should look into improving and maintaining Center Turnpike/Old Town Road as a bypass option should Route 125 wash out again. The few residents along Center Turnpike/Old Town Road will undoubtedly be keenly interested in such a scenario.
Sheldon, Schiff and the ACRPC will now seek funding through the Federal Emergency Management Agency (FEMA) to work up further engineering plans on the leading option. If that option proves viable, towns could seek additional federal aid (up to 75 percent) to build the project.
Middlebury selectboard Chairman John Tenny said it is clear something needs to be done.
“You’d have to be pretty blind to not see the growing intensity and frequency of the storms,” he said.
Reporter John Flowers is at [email protected].