NEW CANAAN — A historic house at 1124 Valley Road may soon come crashing down if negotiations between the property’s owner and preservationist groups in town don’t reach an agreement.

The First Taxing District of Norwalk, which presides over the Norwalk First District Water Department, owns the 4-acre lot where the Grupe-Nichols-Browne House is located. Among its holdings is the Grupes Reservoir, which backs up against the house.

“The house has been off the market for some time. We are no longer interested in selling the property,” Dominick DiGangi, operations and general manager of the Norwalk First Taxing District, said in a phone interview last Friday.

DiGangi said the First Taxing District made a proposal to carve a nearly 1-acre piece of land — which would include the historic house — from their property to sell to preservationist groups for an undisclosed figure. At the same time, the First Taxing District would add pieces of land to its 4-acre lot to comply with the town’s zoning regulations on property setbacks.

“We’re waiting for a response,” DiGangi said, referring to the preservationist groups that have banded together to preserve the house. They include the New Canaan Preservation Alliance, the New Canaan Historical Society and the New Canaan Land Trust.

Chris Schipper, a member of the New Canaan Land Trust and the town’s Conservation Commission, said the reconfiguration process DiGangi suggested would require Planning and Zoning approval.

“There is a challenge in this strategy. It’s a very creative process, but they would require a special permit for a non-conforming subdivision to do this and go through the Planning and Zoning Commission for public session,” Schipper said at a Conservation Commission meeting on April 12.

Schipper said it is a complicated situation, as the New Canaan Land Trust’s initial interest was in the four acres and the house, a deal no longer on the table.

“My response to (the First Taxing District) is that it’s going to take a small miracle to get this approved and to get the Land Trust to work (on this). There’s only one potential player, and that’s the Land Trust. We have to come to an agreement to this and we do want to preserve the house,” Schipper said.

With the house facing possible demolition around May 12 — 90 days after the demolition permit application was submitted in mid-February — First Selectman Kevin Moynihan and Town Council Chairman John Engel have personally entered the discussions to lend their support to the preservationist groups.

In a letter addressed to DiGangi on March 9, Moynihan and Engel asked that both parties work together to “avoid the loss of an historic homestead.”

“These groups have asked me, and I am asking you, to engage in a constructive discussion,” Moynihan wrote. “The 1st Taxing District of Norwalk can get a fair price for the property ... and Preservation Organizations get an opportunity to acquire the property at a fair market price.”

DiGangi said he was surprised to see the letter, as he had met with town officials including Moynihan, Engel and Chris Schipper on March 27, but no agreement had been reached.

The clock, however, keeps ticking. Depending on how the ensuing negotiations continue, the fate of the house may be sealed before then.

“If we’re negotiating and we’re close, we’ll keep talking, but that may not be the case if we’re miles apart (on an agreement),” DiGangi said. “The problem is that the house is vacant and it’s a liability. We’re a water company, not a real estate company.”