Ten years ago, Pam Brown stood across the road from her house in Bethel, Vermont, and watched the rain fall on a field of tall, green corn. The bridge out of town had been closed, and she had nowhere else she could go.
Tropical Storm Irene dumped 10 inches of rain on the mountains north of town, which washed into the White River and sluiced downstream to where Brown stood.
“I watched the river come over the tops of the corn,” she said. “It came curling over in waves, like the ocean.”
Water filled the basement of the home she had inherited from her grandparents. She lost all of her childhood toys and books. It took months of hard work to fix the damage. Brown admits that even today, a certain wet, silty smell – the intimate smell of a river – can make her anxious.
Still, she considers herself fortunate. She knows people in Bethel who lost their entire houses to the river that day. She knows people who still have trouble talking about it. Brown lost a lot, but she didn’t lose her home and she didn’t lose her wedding dress, which was in a plastic tote on a high shelf. She is grateful to have what the river didn’t take from her.
“During Tropical Storm Irene, Bethel was ground zero,” said Mary Russ, executive director of the White River Partnership a nonprofit organization focused on improving the health of the White River Watershed. In addition to homes and businesses, bridges, culverts, and roads were damaged or washed away. “Bethel had more damage to public infrastructure than any place else in Vermont,” she said.
In Bethel and other communities, Irene demonstrated the value of natural flood-control systems, including floodplain forests. In recent years, that call has been heard – and heeded – not only in Bethel, but in Lisbon, New Hampshire, and other locations throughout the Upper Connecticut River watershed.
Natural Relief Valves
Floodplain forests are forests that repeatedly become inundated in the spring or during big storms. These forests are populated by tree species that tolerate flooding, such as silver maple, American elm, speckled alder, and various species of willow and dogwood. They give rivers and streams a place to expand during floods, thereby mitigating damage to human development downstream. Tree and shrub roots secure the soil, preventing river channels from changing course quickly and slowing the water as it moves across floodplains. Floodplain forests also buffer rivers from human influences, trapping sediment and nutrients, such as gravel from dirt roads and the excess fertilizer from farm runoff.
Rivers and floodplains have been important natural resources to people for millennia. In the Northeast, many active floodplains were forested until trees were cleared for agriculture, especially for growing corn, but also for hayfields. Vermont’s forests were 75 percent cleared by the 1850s.
The White River Partnership has undertaken several floodplain restoration projects during the past decade, what Mary Russ has described as, “building relief valves that give water a place to go.” In addition to the many practical benefits of this restoration work, this work also makes good on the promise of the river’s name.
“The White River is called Wôbitekw in Abenaki, which translates to ‘Clear River’ in English,” said Emily Boles, who is of Abenaki heritage and a member of the White River Land Collaborative advisory board. “This provides a glimpse at the river’s historical noteworthy state of being clean and of good quality for fish habitat.” Bethel and other neighboring towns along the White River are among the Abenaki’s homelands, including the tribes of the Sokwaki inhabiting the area prior to the mid-1800s and the Koasek remaining to this day.
Planting Trees to Slow Water
Ten years after Tropical Storm Irene, almost to the day, Will Eldridge, aquatic habitat biologist for the Vermont Fish & Wildlife Department, and Greg Russ, watershed restoration manager with the White River Partnership, hiked across a former cornfield just slightly upstream from the place where Brown stood in 2011. For the past five years, their focus has been to restore a floodplain forest on the 34-acre site.
In October 2020, the White River Partnership contracted with Chelsea, Vermont’s Canonica Farm & Forest Services to level sections of a 6-foot-high, 1,200-foot-long berm with an excavator to reconnect the river to this stretch of floodplain in Bethel. During Irene, the absence of “a natural relief valve” contributed to the flooding of Bethel’s downtown.
Greg Russ pointed to a remaining section of the berm with trees growing on it. Trees are an important part of the plan for the site, he explained. The biggest trees and the parts of the berm they are growing on were left alone, he said, because “trees are speedbumps that slow floodwaters down.”
Eldridge, standing hip-high in goldenrod in the field, explained that this site was last planted in corn in 2015, but hasn’t seen much natural tree regrowth. “I see some trees popping up, but not a lot. We don’t know why. So we’re planting trees.” Greg Russ and Eldridge identified the planted tree species as they walked: basswood, silver maple, and sycamore.
In 2019, 1,000 tree stems were planted at the eastern end of the site, mostly by local schoolchildren. In spring 2021, work crews from the Intervale Conservation Nursery in Burlington, Vermont, and the Vermont Youth Conservation Corps in Richmond, Vermont, planted an additional 4,000 stems.
Rebecca Fors, a Bethel Elementary School teacher, has worked with successive classes of students planting trees with the White River Partnership. Fors said that the activity is especially meaningful to her students because in the fall, her class snorkels in the White River using gear loaned by the Partnership. They see the fish, bugs, and other creatures in the river up close.
Throughout the school year, Fors teaches students that some fish eat the leaves that fall into the river, and that others eat the caterpillars that fall from the trees. Her class also discusses other connections between the river, fish, and trees. The lessons tie to Vermont’s state science education standards for learning about energy flow in ecosystems. When it comes time in the spring to plant trees, Fors said, her students know what’s at stake.
“This hands-on, giving back to their community is more than just having responsibility for this sapling for this 3-hour trip,” she said. The students know their work will help protect their town from floods. “It’s a good reminder that when we give students responsibility, they always rise to it.”
The next time the river rises to what’s known as the 10-year flood stage, it will be free to enter the newly restored floodplain forest, Greg Russ said. The water will slow down as its energy is spread across a wider area, and the trees will interrupt the flow of the water, allowing it to meander instead of simply blasting downstream.
A Renewed Connection in New Hampshire
Forty-five miles northeast as the heron flies, or an hour and a half drive by car, a different floodplain forest restoration project is taking place on the banks of the Ammonoosuc River in Lisbon, New Hampshire, another significant tributary of the Connecticut River. Here, the Ammonoosuc Conservation Trust – owner of the 7-acre site – partnered with the Connecticut River Conservancy and the USDA Natural Resources Conservation Service.
Much of the landscape along the river has changed in the past 100 years or so. Various human activities along the Ammonoosuc, including straightening the river to float timber, have caused the river to dig itself into its channel, explained Ron Rhodes, director of restoration programs for the Connecticut River Conservancy, a nonprofit organization that protects and advocates for the Connecticut River and its tributaries. “The bank was 8 feet straight up and down,” Rhodes said. That steep bank cut off the river from the floodplain.
A key initial step to the work was to use an excavator to reduce the incline of the river slope; this was accomplished in July 2021, Rhodes said. Feats of engineering will help the newly vulnerable riverbank transition to a relatively stable floodplain forest, where the soil is secured by tree roots and stepped terraces rise between the river and the surrounding land.
Rhodes pointed out root balls of full-size trees, which are aimed upstream. The trunks are buried in the bank, he said, and anchored to boulders with cables. Their root balls will remain exposed and point upstream to take the brunt of high water and ice floes.
A crew from NorthWoods Stewardship Center, led by Conservation Science Director Meghann Carter, completed a 2021 tree planting. On four days in late August, the crew planted 2,500 rooted cuttings of willow and dogwood on the site, tucking them in between the thick strands of the anti-erosion fabric that covers the site.
For every site the Connecticut River Conservancy helps restore, Fritz Gerhardt, the group’s conservation scientist, carefully plans the suite of tree species. “I walk the site and see what is there now,” he said. “On a really wet site, we’ll plant black willow, cottonwood, and silky dogwood – trees that don’t mind getting their feet wet. On a drier, sandier site, we would have more cottonwood and maybe put in some pines.”
In the upper Connecticut River, Gerhardt said, silver maple is the dominant floodplain forest tree. “American elm used to be co-dominant, but then Dutch elm disease came along.”
Sugar maple floodplain forests are exceptionally rare, Gerhardt added. Nearly all of them have been converted to agriculture and restoring them is difficult, as sugar maples don’t transplant well. But the upper Connecticut River is home to other types of unusual floodplain forests. “If you go far enough north, you’ll find floodplain forests of balsam firs, spruce, and cherry,” he said. “It’s a unique environment.”
A Remnant of the Ideal at Maidstone Bends
Gerhardt thinks the best place in the upper Connecticut River to see a mature floodplain forest is in the Maidstone Bends section of the river, at Guildhall, Vermont, and Northumberland, New Hampshire, about 32 miles south of the Canadian border. A mix of agricultural land, some restored floodplain forests, and remnants of mature, untouched floodplain forests surrounds this series of meanders in the river. The Connecticut River Conservancy is working with The Nature Conservancy (TNC) in this area of the watershed, and land on both sides of the river is conserved here.
“Maidstone Bends has emerged as one of our highest conservation priorities on the Connecticut River, because there are some sites with existing floodplain forests and others with restoration opportunities,” said Mark Zankel, executive director of The Nature Conservancy in New Hampshire, which has been working for more than a decade with other TNC chapters in the watershed to conserve and restore floodplain forests. “It’s important that this area is still flooding in a semi-natural way. There is a dam upstream, but the area still floods.”
On the remnant sites, towering silver maples flash the shining undersides of their leaves in the breeze. Along the river’s tributaries, they shade the water, creating habitat for cold-water fish such as brook trout. These floodplain forests warm up earlier in the spring than the surrounding landscape, providing a rest stop for migrating songbirds.
Mature floodplain forests provide breeding grounds for songbirds such as the cerulean warbler, northern oriole, and great crested flycatcher. They offer habitat to water-loving mammals such as beaver, mink, and river otter, as well as amphibians including wood frogs and blue-spotted salamanders.
“The remnant patches of floodplain forest at Maidstone Bends give us a reference to what a successful restoration might look like,” said Zankel. “Floodplain forests are among the most interesting, unique, and important ecosystems out there. We always knew they are important for wildlife, including fish and migrating birds, and now we know they are important to human communities as well.”
While the benefits of floodplain forests to people and infrastructure are not in the spotlight at Maidstone Bends, they play a central role in places such as Bethel, Vermont, and Lisbon, New Hampshire. The Northeast needs the relief valves created by floodplain forests now more than ever, and that need will only increase as our climate continues to change, Rhodes, Mary Russ, and other river advocates say.
Changing Climate, Changing Forests: The Impacts of Climate Change on Forests of the Northeastern United States and Eastern Canada, a 2011 report from the U.S. Forest Service, stated that, “Both the intensity and frequency of extreme precipitation events have increased over the past century.” The report also predicted that storms would continue to intensify in the future.
Like floodplain forests throughout the Connecticut River watershed, a floodplain forest upstream from Bethel’s downtown means enriched wildlife habitat for the deer and other animals already wandering the site, the smallmouth bass and suckers congregating under fallen tree trunks in the White River, and the bald eagle soaring along the river corridor – all seen during the site visit this past summer. It also means less public money spent on repairing bridges and roads from floods, and that more basements stay dry and more treasured memories survive to be passed on to future generations.
This article and the accompanying infographic, Stream Crossings Reimagined, were made possible by a grant from the Davis Conservation Foundation.
Discussion *