A heated dispute Monday over whether dogs should be allowed on property that forms Sonoma's backdrop nearly derailed the City Council from formally authorizing acquisition of the site.

The council voted 3-2 to accept ownership of the Montini Preserve, a 98-acre hillside parcel that promises to open up sweeping vistas of the city to the public.

Councilman Steve Barbose, however, argued that the city should not move forward Monday with the transfer unless leashed dogs are permitted on the property.

"This isn't the deal I thought we were making," Barbose said. "It's that simple for me."

Barbose directed his comments at staff members of Sonoma County's Agricultural Preservation and Open Space District, including General Manager Bill Keene, who were present Monday.

The district, which currently controls the property, has a management plan for it that includes a prohibition on pets, including dogs.

The provision was put in place in 2008 when the Open Space District was considering transferring the property to California State Parks, which does not allow dogs at places under its authority. The state's budget problems derailed that plan.

Keene appeared sympathetic to dogs being allowed at Montini. He noted dogs are permitted at other properties acquired by the Open Space District, including at Healdsburg Ridge Open Space Reserve.

Barbose and Council Member Laurie Gallian said Keene should have agreed to a provision allowing dogs at Montini simultaneously to the council signing off on the terms Monday night.

"I don't see why we can't be consolidated in our causes here," Gallian said.

But Keene presented the issue as a lengthy one, demanding additional environmental review, and he said the Open Space District staff was "not going to spend our time and effort to amend" the document.

"That's really an issue you should take on as a city," he said.

With the council's vote Monday night, the Open Space District is expected to formally agree next Tuesday to the transfer at a meeting of its Board of Directors, which is the county Board of Supervisors.

"Never in my wildest imagination did I consider sitting here tonight and consider passing on a golden opportunity for the city," Mayor Ken Brown said before the outcome of the council's vote was clear.

The Open Space District bought the Montini Preserve and an adjacent 59-acre conservation easement in 2005 for $13.9 million, including a $1.15 million contribution from the city.

The property forms much of the city's backdrop and is historically significant because it was part of the foothills bought in 1850 by Gen. Mariano Vallejo.

The plan calls for the Open Space District to transfer both parcels to the city basically at no cost, except for fees related to the transfer, and the city eventually picking up maintenance costs.

Sonoma dog owners, who've long complained about a dearth of places to exercise their pets in the city, long have coveted the opportunity to use the Montini Property if it became available.

But several speakers Monday expressed opposition to the idea.

"It seems to be a conflict of interest to have an area for wildlife and to introduce dogs into that," said Russ Bair of Sonoma.

Council Member Tom Rouse, who made the motion to adopt the resolution that allows for the transfer, also expressed concerns about letting dogs on the property.

"If it's truly a preserve and we're trying to keep wildlife in its natural habitat, the introduction of dogs to that habitat could certainly put that in jeopardy," he said.

The City Council could seek an amendment to the agreement to allow dogs at a later date. The Open Space District has final say.

The agreement approved Monday includes a memo of understanding that the district will negotiate in good faith with the city if it decides to pursue an amendment to allow dogs.

Currently, however, it appears there aren't enough votes on the council to support such a move.

Plans call for the Open Space District to finish building two miles of trails before the property is opened to the public. That's not expected until late 2014.

The Sonoma Ecology Center submitted a proposal to the city to do maintenance work on the property, a three-year deal worth $70,000. The Open Space District would reimburse the city for that.

Annual maintenance costs for the property in future years are estimated at $12,000 to $15,000, which would come from the city's general fund.

You can reach Staff Writer Derek Moore at 521-5336 or derek.moore@pressdemocrat.com. On Twitter @deadlinederek.