On a sheet of notebook paper, retired government meteorologist Andrew Woodcock draws what he calls the worst-case scenario for flooding in southwestern New Hampshire's mountainous Monadnock Region.
Blue and pink colored-pencil lines mark out a dying cold front over northern New England. Then he adds a tropical storm heading north in green.
If the front holds up the tropical storm, it could dump a lot of rain on the region very quickly, he told the Keene Sentinel. He dubs the imaginary storm Imelda and estimates it could produce 15 in. of rain in that part of the state.
With serious storms becoming more common and a warming atmosphere able to hold more water than in the past, this is not an out-of-left-field scenario.
"That's in the realm of possibility," Woodcock said, tapping the tip of a pencil against the point that represents the town of Keene, the region's largest community.
Catastrophic flooding in central Texas over the Fourth of July weekend that killed close to 200 people has raised alarm nationwide about increasingly common extreme weather events, the adequacy of warning systems and recent cuts to the National Weather Service.
While Monadnock Region residents have not had to contend with the scale of flooding and devastation that the Lone Star state suffered, they are no strangers to deadly flooding.
In 2005, four residents died amid the dangerous rush of Warren Brook and the Cold River crashing through Keene, destroying three dozen buildings and damaging 71 homes. Yet, 20 years later, the event is no longer at the forefront of local residents' minds.
Despite that, flooding is one of the top hazards for the region, with events in 2021 and 2023 leaving several buildings and roads heavily damaged.
Federal, state and local governments have systems in place to prevent and respond to extreme floods, but are those systems sufficient to tackle increasingly common and severe flooding? And what impact could federal changes to those systems have on local response?
Lay of the Land
Extreme flooding in the Monadnock Region is different than in Texas due to differences in the landscape and water infrastructure, which shape the flood risk in New Hampshire.
"One of the things that works against you is you're in a bowl," Woodcock said in answering a question from a Keene Sentinel reporter.
The city sits at the bottom of a shallow valley at the convergence of 12 rivers and streams. Six major watersheds drain into it, according to Keene's 2018 Hazard Mitigation Plan, and the Ashuelot River is relatively broad and flat through town, meaning water does not flow out of that bowl very quickly.
Like Keene, many other Monadnock Region towns are built along waterways because access to rivers and streams was important to early settlers.
But with homes and businesses built beside water in low-lying valleys, the features that made those towns prime settlements back in the day now make them prime targets for flooding.
By developing roads and homes along river banks, humans have had a hand in creating conditions that often lead to flash flooding, said Marilla Harris-Vincent, a New Hampshire river steward with the Connecticut River Conservancy (CRC).
"The water doesn't have anywhere to go," she told the Sentinel, after having witnessed the same situation in Acworth. "They've had some really extreme flooding events. And it's because it's a very narrow channel that the water just kind of shoots down through and then it opens up into [a] man's farm field."
Flood resiliency is a common aspect of the CRC's restoration work in the Connecticut River watershed, added Harris-Vincent.
"Things are so built up these days that there isn't a place for water to go, and so it's sort of just funneled down the river channel and when it gets an opportunity to [overflow], that's what happens. And these areas that we're living in are becoming floodplains now because they've been developed and built up."
Efforts to reduce flooding risk can include adding riparian vegetation — or plants along river banks — that serve as a buffer for overflowing water by allowing water to seep underground and into aquifers rather than across impervious surfaces like roads and parking lots.
Harris-Vincent also noted that communities across the country are working to make flood resiliency a part of their comprehensive plans in the wake of more extreme weather events and flooding.
Many quintessential New England villages that are nestled between high hills and low river basins are particularly susceptible to flooding, Woodcock said, as he recalled the severe flooding in rural Vermont in the summers of both 2023 and 2024.
Incredibly, since the Sentinel's recent conversation with Woodcock, many of those Vermont towns flooded again in July 2025, the third year in a row that catastrophic floodwaters have slammed Vermont on that exact date.
A volunteer fire department in East Burke, Vt. said the Passumpsic River rose about 5 ft. in just minutes. While that doesn't compare to the estimated rise of the Guadalupe River during the July 4 floods in Texas, it was enough to overwhelm culverts, brooks and bridges with little to no warning, trapping some residents, damaging roads and bridges and filling homes with water.
And it happened just as Woodcock described, with a band of rain dumping a lot of water all at once on small towns along waterways in the bottom of valleys.
Several Older Dams Ready for Replacement
While that has proven to be the Monadnock Region's geographic disadvantage, that part of southwestern New Hampshire has also been the site of significant public works projects to mitigate flooding.
Three major flood-control dams operated by the U.S. Army Corps of Engineers (USACE) help to mitigate flooding on the Ashuelot, Branch and Merrimack rivers in the Monadnock Region. When those rivers rise, rangers close gates at the dams to reduce the flow of water to downstream areas, noted Christie Baker, the project manager for Otter Brook and Surry Mountain Lake, in an email to the Sentinel.
"Our park rangers are responsible for the operation and maintenance of each dam and work closely with our team of engineers in the Reservoir Control Center in Concord, Massachusetts to monitor river levels and weather conditions," she wrote. "This dedicated team decides when to close gates to store flood waters."
When conditions improve downstream, the stored water is slowly released so the dams can regain flood storage capacity for the next event.
Since their construction in the 1940s and ‘50s, the trio of dams has prevented about $150 million in flood damage, according to USACE.
The City of Keene and the federal agency also have collaborated on flood-control measures along Beaver Brook, including the construction and maintenance of retaining walls that are familiar sights to many East Keene residents.
Regardless, flash flooding can quickly raise the level of various sized waterways in the region like the Cold River in northern Cheshire County. With many of the region's smaller dams on rivers, brooks and streams being privately owned or managed by municipalities, however, they may not be up to the task of holding up under record storms.
At least 26 Cheshire County dams were built before 1900, according to the USACE's National Dam Inventory.
Throughout New Hampshire, dams built a century or more ago are deteriorating and pose a hazard to the cities and towns that are within their potential floodplains.
In Cheshire County alone, there are seven state-regulated dams that are considered to be "high hazard," meaning their failure would likely result in the loss of human life and/or cause significant property damage; or in "poor" condition, meaning those dams likely would not hold up under heavy rains that have occurred before in the region.
For instance, two decades ago, an earthen dam near Lake Warren in Cheshire County failed, causing several ft. of lake water to surge into a small stream feeding the Cold River. The resulting wall of water demolished buildings and roads and killed several people.
Since then, the infrastructure failures that led to the flooding have been repaired and strengthened.
Future is Now
Making a firm prediction as to whether a weather event in the Connecticut River watershed like what led to the recent flooding in Texas is next to impossible, said Harris-Vincent.
"But what you can say is that we are seeing more frequent and intense storm events, especially as a result of climate change," she said, while noting that precipitation is on the rise in New England.
Another extreme flooding event could leave the Monadnock Region grappling with severe road wash-outs, stranded towns or neighborhoods, water contamination, delayed or restricted emergency medical services, utility failures and millions of dollars in damage.
Even more unsettling for area residents is that experts believe serious flooding events are becoming more likely.
The risk for the region's residents is not just in the initial event, Gilsum Emergency Management Director Dee Denehy told the Sentinel in April 2025.
When a small town loses a key road or bridge, people can be left stranded without water, medical supplies and other necessities, he said, as was seen in North Carolina and Tennessee's mountain communities last fall and winter in the aftermath of Hurricane Helene.
Even the smallest towns typically have an emergency manager and hazard mitigation plans in place, but those plans are shaped by what has happened in the past — something Woodcock said is not a great predictor of what could happen in the future due to the impact of climate change.
"You can't go on what things were like 50 years ago," he said.
Harris-Vincent said the region's seasonal weather patterns are changing as evidenced by rain, rather than snow, coming down during the winter months.
"And then that rain is ... causing runoff, which means that less groundwater is being infiltrated. Instead, it's just becoming runoff, which creates big influxes of water into rivers and storm drains and areas that aren't necessarily equipped to handle such intense … storms," she said.
Winter rains are not the only problem; summers have been wetter, too.
"Normally, you see high-water events when there's spring runoff, but now, in July, which is usually a much drier time of the year, [what] we've been seeing in New England over the last two years are these extreme floods happening in the middle of the summer," Harris-Vincent said.
She also noted that more intense and localized storms are becoming the norm in the region as slow moving clouds have in recent years tended to sit above one area and drop tremendous amounts of precipitation.
"So, [they're] like super-localized storms, which is different from what we're used to seeing," according to Harris-Vincent.
