Lessons learned from Irene reflected in less flood damage last week
|Published: 07-17-2023 9:23 PM
BETHEL — On Monday night, the Third Branch of the White River swallowed up Bethel’s athletic fields and bit off chunks of gravel roads. Stranded in homes unreachable by car, 15 people were rescued Tuesday afternoon, and one more resident on Wednesday.
The heart of Bethel sits at the intersection of the upper White River and the river’s Third Branch, which pull from different watersheds — or the area of land that channels rainfall and snow melt into streams. The town has learned the hard way how to buckle down during a big storm. One in particular looms large in public memory.
In August 2011, Bethel incurred over $5 million dollars in damage to public infrastructure during Tropical Storm Irene, the most of any town in the state, according to data from the state.
This Monday, seven inches of rain fell on Bethel, adding to an already swollen White River following heavy rain the previous Friday and Sunday. But “this time, there were no injuries, no major property losses, no home losses,” Town Manager Therese Kirby said. The brunt of the recovery work in town has the painstaking documentation required by the Federal Emergency Management Agency, or FEMA, to recoup disaster funding.
It was a lesson in thoroughness carried over from Irene. On Thursday, Kirby stood over maps of the town’s roads, annotating in cramped pencil writing — which were passable, and which still weren’t. She spent five hours on Wednesday with the chair of the Selectboard, Chris Jarvis, driving across all reaches of town and taking photos to send to the federal government.
While road damage required rescues and paperwork, other infrastructure in town made it soundly through the storm.
The Bethel septic system was totally submerged on Monday night. But due to upgrades made to the system after it failed during Irene, it was able to come back online.
“I was so relieved,” Kirby said.
As the waters recede, similar stories of bridges and roads that held out are being told across the Upper Valley.
The Taftsville Covered Bridge in Woodstock, bolstered with protections after Irene, was closed due to a high, boisterous Ottauquechee River, but it pulled through the flood safely. In West Fairlee, around 60 feet of streambank armor installed after Irene along Beanville Road was damaged, “but the majority of the 2011 work from that location to the town line was undamaged,” according to a Listserv post from Delsie Hoyt, chair of the Selectboard.
“You hope that every event like this keeps people alert and thinking of the future,” said Frank Magilligan, a Dartmouth College geography professor and river scientist, in The New York Times this week. “It’s not going to be a one-off, and you can’t put your head in the sand.”
On Monday night at the West Hartford Bridge, about 20 miles south of Bethel, a water gauge managed by the United States Geological Survey measured 40,000 cubic feet of water per second rushing through the White River.
During Irene, the same gauge recorded 90,000 cubic feet per second.
“Actually, Irene broke the gauge, so that’s even an extrapolation,” said Mary Russ, executive director of the White River Partnership, a Royalton-based nonprofit that invests in the health of the White River and its watershed. “That’s like 90,000 basketballs moving down the river in a line.”
A warmer atmosphere holds more moisture, and scientists say that as climate change drives temperatures up, it will also bring more precipitation to New England.
Currently, Vermont is seeing 300% more precipitation than what would normally fall this time of year, Russ said. But over the past eight years, Vermont has also weathered historic drought. Last summer, the White River was lower than it has ever been on record.
“It’s more overall, but sometimes it comes all at once,” Russ said. “It’s just this boom and bust cycle of precipitation.”
In Irene, around 1,000 culverts failed across Vermont, according to the state.
“When a culvert fails, all the infrastructure around it also fails,” Russ said.
In 2011, heavy rain fell on the spine of the Green Mountains, plugging culverts in higher elevation towns with sediment and snarled branches. Water was then let loose upstream in the White River watershed, flooding places like Rochester and Stockbridge and beginning on a steep decline that would only increase its power before devastating a town further downstream, like Bethel.
“It was a domino effect,” Russ said. “You saw entire stream systems and transportation systems fail top to bottom. The collateral damage was enormous.”
The state now requires culverts, when they fail or when they are built afresh, to be constructed at bank-full width, which is the height of water right before it jumps its banks. That kind of event is happening every other year or so, Russ said.
“Anecdotally, those bigger culverts got through this week’s storm fine,” she said. “Those newer structures are passing these flows. The roads aren’t washing way, the houses next door aren’t washing away, cemeteries aren’t washing away. Bad things happen when those structures blow.
“Before Irene, we were tree huggers,” she added. “Now we’re culvert huggers.”
Along Route 14, from in parts of Royalton, Bethel and Randolph, the First and Second Branch valleys of the White River — where agricultural fields and forested land follow the waterway — flooded over.
“There are portions of those valleys that are still wall-to-wall water right now,” said Rudi Ruddell, a watershed scientist with the White River Partnership, on Wednesday.
It sounds menacing, but it means that floodplains are working, Ruddell said.
“Those floodplains are storing an enormous amount of water right now,” he said. “That keeps it from going downstream to slam somewhere else.”
When floodplains stop functioning properly — due to the development of impermeable surfaces — or when a river has been detached from its natural floodplain to accommodate agriculture or transportation, water that’s not flowing out onto receiving land becomes deeper and hungrier.
“If you think about crossing a stream in a foot of water versus crossing a stream up to your waist, you get a pretty quick idea of what the difference in the force of that water is,” Ruddell said.
Recognizing its vulnerable position in the watershed, Bethel has been proactive in leveraging open space as flood mitigation, Russ said.
“They can’t move the village right? That’s not feasible,” she said. Instead, what the town and residents have focused on is conserving open space upstream, “those places where water will spill out onto.”
Along with the White River Partnership, Bethel’s Conservation Commission has helped secure over 50 acres of land upstream “so that land will always be available as a flood-release valve,” Russ said.
“Talking to colleagues and community members in the upper reaches of the watershed, they said it worked amazingly well in this flood. And we’re not looking at another million dollar bond to protect the roads.”
What Russ calls “a network of green infrastructure” allows water to slow down, drop sediment and trees, so by the time it reaches Bethel, it’s not as hungry for land as it would be otherwise.
But conserving land is not an easy project, she said.
The Vermont Agency of Natural Resources has developed a river corridor easement that provides compensation to landowners to protect land that will actively flood, “but that’s not a great fit for every land owner,” Russ said.
When land floods — “and you’re looking at feet of mud, and sometimes things even worse, like propane tanks” — the burden falls on the landowners to get it back to how it was, Russ said.
Four properties along the Third Branch of the White River and its tributaries in Bethel were bought out through a partnership between the Two Rivers-Ottauquechee Regional Commission, FEMA and the U.S. Department of Housing and Development after Irene. The project paid landowners the pre-flood value of their properties. Along the rest of the river in the Upper Valley, four properties in Royalton, nine in Hartford and one in Sharon were also purchased.
On Monday, downstream on the banks of the White River in Sharon, Chris Carroll was working on a home that was destroyed in Irene when he saw waters rising once again toward his project. But while water filled the basement during Irene, it didn’t crest the banks this time.
But even the threat of flood was “kind of awe-inspiring,” Carroll said. “(Irene) was supposed to be the ‘100-year storm,’ but something like it happened again.”
Carroll’s renovation is following FEMA guidelines, which include winding special flood vents through new buildings in a floodplain and using materials that can take water so structures don’t suffer as much damage when they do flood again.
The FEMA guidelines are imperfect, Carroll said, and price people out of land they once could afford.
“A lot of people are losing their homes because of this sort of thing,” he said.
“It’s a huge issue because the state comes through and all the sudden says your entire property is in what we call a ‘fluvial erosion area,’ where there are all these expensive restrictions, but you have to pay the same in taxes. Your property is devalues, but you don’t get a tax break.”
Still, he noticed that neighbors were much more cautious this go-around than they were during Irene.
“Irene opened everyone’s eyes to the risk and put people in a situation where they were much more aware of the dangers of a flood,” Carroll said. “People realized that they really can lose everything.”
Frances Mize is a Report for America corps member. She can be reached at firstname.lastname@example.org or 603-727-3242.