The plan is to build 84 single-family homes and a 12-unit apartment building on 12 acres of the 459-acre property.
"It's kind of the state-of-the-art in development to really cluster, to minimize your footprint and maximize undeveloped open space," said Norm Dyer of Loving & Campos Architects.
The homes would be located on the flat section of the property, close to the road. By opting for a high-density development rather than spreading the houses throughout the hills, a greater portion of the land would be preserved, he explained.
The biggest portion, more than 200 acres, would be dedicated to East Bay Regional Park District for preservation. The plan also sets aside 24 acres for mitigation and includes a 182-acre scenic easement.
"I think it's a good project all-around," said Dyer. "It's got a lot of community benefits to it, no real impacts and it's a desirable product."
Town leaders held a special meeting last Thursday to tour the site. Dyer and other project representatives pointed out its potential benefits - for example the now-private property would be available for hiking, mountain biking and other outdoor activities.
The plan includes a 12-car parking lot connected to a pedestrian trail that travels up the ridge. The land would also be accessible by foot from the back side, near Bollinger Canyon Road.
The Elworthy family raised cattle on the 150-year-old ranch for generations before recently deciding to sell a piece of it for development.
About 10 years ago they nearly sold the land to developer Suncrest Homes, which planned to build 224 luxury houses, some going all the way up the ridge. The proposal fell through because of soil runoff and landslide issues.
The family then partnered with the O'Brien group and came up with a less intrusive proposal. Five acres will be set aside for the Elworthy family, including one existing home and a private equestrian facility.
When this project was first introduced, many nearby residents approached the town with their concerns.
At a public hearing Jan. 8, they voiced concerns about aesthetics and increased traffic and noise, particularly during the construction period.
Others were worried the development would make existing drainage problems in the area worse. Dyer said a detention basin - essentially a holding pond - was added to the plan to help improve the drainage system.
At the hearing the staff reviewed an environmental report that was prepared for the project. The results showed the development would have very little impact on the environment, and none that couldn't be mitigated.
The Planning Commission will hold a public hearing at 7:30 p.m., Tuesday, May 13, at the Town Meeting Hall, 201 Front St.
After hearing comments, the commission will make a recommendation to the Town Council. If it recommends approval, there will be another opportunity for public comment before the council votes on the project.