WILLIAMSTOWN, Mass. — You cannot really know where or when the next natural disaster is going to hit.

 

But you can consider the possibilities and plan for the worst.

 

On Thursday at 6 p.m., Williamstown takes a step in that planning process when it holds a listening session for members of the public to consider the Municipal Vulnerability Plan the town is developing with the help of a grant from the commonwealth and advice from the Berkshire Regional Planning Commission.

 

BRPC senior planner Lauren Gaherty will lead a discussion about the data that has been collected and the threats that have been identified by a town-sponsored working group that last month held a daylong workshop.

 

Town Planner Andrew Groff this week explained that the MVP, a state initiative, will help Williamstown develop an updated Hazard Mitigation Plan, which he hopes to complete by later this year.

 

"To qualify for [Federal Emergency Management Agency] grants, like the one we received for the Spruces, we have to maintain an up-to-date, FEMA-approved Hazard Mitigation Plan," Groff said.

 

Although the MVP is a separate document, it will help inform the more comprehensive Hazard Mitigation Plan. And the MVP alone will help the town qualify for other grants.

 

Williamstown is one of several communities in the Berkshires in various stages of the MVP process, Gaherty said on Tuesday.

 

Adams will have its public forum next Thursday, June 14, at Town Hall. Lanesborough and Monterey currently are in the middle of their processes. And Dalton, North Adams, Pittsfield, Sandisfield and Sheffield each were successful applicants in the second round of MVP grants. The state has also set up a "climate change clearinghouse" to gather data for planning ahead for severe conditions.

 

The more towns that go through the process, the more their findings can help inform the discussions in other towns, Gaherty said.

 

"We have some of the data we can pull and use for the next towns," she said. "But it really comes down to the local level: Where do you have flooding in your town. Every town experiences it slightly differently. It's really important to plan on the town level to help them to … identify the risks and get grants or get things in the town meeting budgets for capital improvements and that sort of thing."

 

The threats to local communities are changing as the climate changes, and the data point to a combination of more frequent and severe weather events (rain storms, ice storms and the like) coupled with more frequent droughts.

 

"I think our big risks in Williamstown include … these big temperature fluctuations in the wintertime," Groff said. "Look at the ice jams we had in the Green River. That's a big issue. The extremes are getting more extreme. In the wintertime, you have these rapid melts that are a problem. Or there's the possibility we could get more ice storms than snow storms, which would lead to more sustained power outages.

 

"But the biggest thing overall from a climate change risk perspective is a warmer atmosphere that can hold more moisture and create larger, quicker bursts in precipitation. We've seen it locally with the flash flooding that occurred in 2013. It was super localized, right along the Taconic range. One of the more nationally known stories is those poor folks in Ellicott City, Md., who got hammered with two 'thousand year' flash floods within two years of each other."

 

A weather event does not have to be a "named" storm or a catastrophic event like Tropical Storm Irene to cause significant damage. An event like the 2008 ice storm cost the state more than $7 million and left more than 1 million Massachusetts residents without electricity, some for as much as two weeks.

 

"I think we need to think about how our rain patterns are evolving and how [Ellicott City] could happen to us, too," Groff said. "Luckily, our downtown is not in a narrow, tiny valley surrounded by streams. But we definitely have some streams that are susceptible to flash flooding."

 

The Thursday evening meeting will be a chance for residents to learn about some of the threats that have been identified and share information about potential problems that may not have been considered.

 

"We're going to basically report out what we heard in the workshop," Gaherty said. "There will be a short presentation to set the stage for the public about changing weather patterns, and we'll say, 'This is what people found in the workshop. These are the biggest changes that should be addressed.'

 

"And then we'll ask, 'Did we get it right? Did we miss anything? What are your thoughts?' Basically, we're going to ask the public to weigh in."