MONTPELIER — A decision by the Federal Emergency Management Agency to authorize full payment of the cost of replacing a culvert destroyed by Tropical Storm Irene flooding could mean up to $6 million for other Vermont communities that had to do similar replacement projects, the state’s top recovery officer said Monday.
FEMA has agreed to upgrade damaged culverts, of which there are several dozen across the state, from their pre-Irene condition, but not for the full costs sought by many communities that are seeking to use improved designs that will better enable streams and rivers to flow more easily beneath roads and other obstacles.
FEMA has said the state’s rules before Irene hit in August 2011 were not adequate to warrant paying for the full upgrades.
But Dave Rapaport, Vermont’s chief Irene recovery officer, said the agency’s decision Friday to help Townshend with the cost of replacing a corrugated metal culvert with a concrete arch is reason for the state to hope that more money will be flowing soon.
‘‘While we do believe this will apply to a number of other projects, they will each have to be looked at on a case-by-case basis,’’ Rapaport said.
On Friday, FEMA agreed to pay about $100,000 more than the $440,230 it previously approved for Townshend.
The decision only affected that particular case, but Rapaport said Townshend and the state hope the same rationale used there can be applied more broadly.
‘‘It is important to note that the facts and circumstances of each project are unique and that this decision was specific to only this one project in Townshend,’’ said FEMA spokesman David Mace. He declined to speculate whether other projects could get the same approval.
FEMA’s public assistance program is designed to bring damaged infrastructure back to predisaster conditions.
They will pay for upgrades if those upgrades are mandated by a clearly delineated code or standard by a government entity, but FEMA did not believe that the standards Vermont had in place before Irene hit were applied uniformly, said Rapaport.