MONTPELIER, Vt. – About a dozen fires have devastated downtowns from one end of Vermont to the other since 2000, and U.S. Sen. Patrick Leahy says he has a plan to prevent more destruction by encouraging building owners to install sprinkler systems in older buildings.

Leahy used downtown St. Johnsbury, which suffered three devastating fires in recent years, including one that killed three people, as the backdrop Friday to announce that he has introduced the Historic Downtown Preservation and Access Act.

The legislation would provide refundable tax credits of up to $50,000 to business owners who improve existing buildings. The credits could also be used to install elevators.

“Since 2000, the federal government has invested more than $30 million into rebuilding burned-down buildings in St. Johnsbury, Brattleboro, Hardwick, Enosburg, Springfield, and Wilmington,” Leahy, a Democrat, said in a statement.

The federal rebuilding expenditures could be saved if the fires are prevented, he said.

Leahy said that each year fire destroys hundreds of vulnerable historic buildings across the country that serve to anchor villages and downtowns. He said the upfront investment he is proposing would help prevent the loss of life, reduce property damage, and decrease federal expenditures on rebuilding after the fires.

The series of fires in Vermont downtowns over the years has left gaping holes in these communities. In St. Johnsbury, a Daniels Block fire in 2000 killed three people; a fire hit a Main Street building in 2009; and the Landry Block fire broke out on Railroad Street in 2012.

Just last month, construction began on a $24 million project in Brattleboro to rebuild the historic Brooks House, which was heavily damaged by fire in 2011. Major fires also have hit Springfield in 2004; Hardwick and Enosburg Falls in 2005; and Wilmington in 2010.

After the 2009 fire, St. Johnsbury Fire Chief Troy Ruggles asked Leahy if more could be done to prevent future fires.