Instead of selling fresh food on the busiest brunch weekend of the year, the Williamsburg Snack Bar spent Mother’s Day pumping 3 inches of water out of its restaurant.

“It kept coming in because the groundwater level was so high,” owner Meaghan Dunphy explained.

For six days in May, Dunphy and her team worked “around the clock” to push out groundwater that seeped in through the right side of the building. The water bubbling up from below merged with runoff from an uphill solar field that has replaced forestland. In less than one week, Dunphy estimates she lost $26,000 from lack of customers, spoiled food and damage.

“We have awesome customers who generously stepped up and started a collection,” Dunphy said. “They even offered giant fans and humidifiers. So I’m thankful for that.”

The popular seafood spot suffers from the same problem that’s soaking farm fields, submerging basements and squeezing construction: the groundwater tables in Massachusetts’ underground aquifers are rising.

As weather in Massachusetts gets wetter and warmer — a consequence of climate change — these already shallow spaces absorb less water during storms that continue to rise in frequency and intensity, causing pooling and flooding in areas that never used to experience it.

“In sort of simplistic terms, the land’s ability to absorb the rainfall has been compromised,” said Stephen Taranto, program coordinator at the South Deerfield-based Community Involved in Sustaining Agriculture (CISA).

Underground aquifers act as natural pipes and storage tanks for precipitation. Plants and animals drink this water supply during summer and autumn, then snow and rain in winter and spring replenish the aquifers.

But as Massachusetts sees a hike in the yearly amount of precipitation, so too are these aquifers.

In fact, University of Massachusetts Amherst hydrologist David Boutt and one of his graduate students found that groundwater levels have climbed a couple inches every year for the past 70 years.

“I know it doesn’t sound like a lot,” Boutt said, “but if you already have shallow water tables or shallow depth of water, raising those levels by a foot or 2 feet over 50, 60 years is substantial.”

Changes in underground aquifers are directly tied to Earth’s ability to cycle water from land to sea to sky.

Christine Hatch, a UMass Extension professor who specializes in hydrology, explained that warming global temperatures allow the atmosphere to hold more water, thus intensifying storms and releasing more total water per storm than in previous years.

“One of the things that’s been happening is we’ve had these very, very wet years punctuated by very dry years,” Boutt said. “This kind of intensification of the hydrologic cycle is what you expect in a kind of a planet that’s warming. Things are going to get more intense with bigger floods and bigger droughts.”

Increased amounts of impervious surfaces from roads and buildings also prevent precipitation from uniformly soaking into the ground, causing “nuisance pooling” in urban areas or overwhelming stormwater and sewer systems.

“Between the impervious surfaces and these more intense storms, if you add to that the fact that the groundwater table is higher, you might also have water coming out of the ground in areas when [precipitation] does infiltrate,” Hatch explained. “It’s like triple compounding factors.”

Water tables high, shallow

As seen through the Hydrogeologic Atlas of Massachusetts, a series of maps created by Boutt that measure depth, conductivity and transmittivity of aquifers across the state, the Pioneer Valley’s water tables are particularly high and shallow. Boutt explained that this comes from the geology of the valley.

During the creation of the valley, the mountain’s composition of soft rocks broke into very fine sediment when glaciers, lakes and rivers carved through them. The low permeability of this sediment prevents water from passing through to deeper levels, keeping the underground aquifers shallow.

Rising groundwater tables pose all sorts of challenges for both the environment and infrastructure. If a septic system’s drainfield overflows, for instance, it can slow down the system’s ability to filter wastewater.

High groundwater tables also increase the likelihood of flooding in and around properties. As part of the hydrologic atlas project, Boutt released a survey to residents across Massachusetts about their experiences with groundwater. While the majority of the 2024 survey results are set to be released later this summer, Boutt confirmed that 75% of the roughly 1,000 responses reported flooding in or around their property. Survey participants also said that these incidents happened in January or February, a couple months before water table levels peaked.

“That was a little bit earlier than we would expect,” Boutt said. “I think part of that probably has to do with our changing winters, too. Sometimes we get these rain on snow events that can kind of cause, you know, surface ponding of water that won’t necessarily make it as easily into the ground.”

One farm’s experience

However, it’s different for small businesses like Williamsburg Snack Bar and Granby farm Dave’s Natural Garden, which are impacted by the peak of water table levels in spring.

The Granby farm is around wetlands with already high water tables, so even short bursts of heavy rain could potentially ruin crops. Co-owner Meghan Hastings said her potato crops this season rotted when wet weather delayed plantings, and a subsequent rain washed away all the topsoil.

“I think the historic average for a total number of inches of rain in July is around 4 inches, or something like that,” Hastings said. “If you look at what we’ve gotten each July for the last five years, most of the years has been tremendous amounts of rain, like 10 inches or 11 inches.”

After several seasons of diminishing returns, the wet conditions have forced Hastings to plant on only the driest 3.5 acres of their 10-acre parcel, while covering the remaining 6.5 acres with cover crops. Tractors struggle to navigate drier fields, so more work is required to prepare the plots.

“We’re doing more intensive plantings where as soon as a plant is harvested, roots get removed, and then something else gets planted in its place,” Hastings said.

The farm has also transitioned to growing more crops in greenhouses and raised beds. Hastings greatly reduced tilling practices and tractor usage to prevent small sediment from sinking deeper in the soil and further compacting the already dense soil.

Possible solutions

Taranto, who advises farms on solutions to flooding, said a system of tile drains is becoming more popular in larger fields, but is still too expensive for many small farms.

CISA has also begun to restore a handful of 10,000 to 13,000 miles of ditches along the Connecticut River that have historically managed flooding for centuries.

“The capacity of those ditch networks to receive excess rainfall, which were originally built under a different climate regime than we have now, has been compromised,” Taranto explained. “They weren’t engineered to handle a lot of water at once.”

However, Hatch suggests the best solution to flooding from precipitation or groundwater is simply allowing water to flow where it wants to, whether that’s moving infrastructure, removing dams or creating more permeable surfaces in developed areas.

“If you can allow water access to its historical ponding places and wetlands and low places,” Hatch said, “you’re really much better off because if the water goes in there, it slows down, it spreads out and might infiltrate. That just mitigates more trouble downstream.”

Emilee Klein can be reached at eklein@gazettenet.com.