Sonoma County funds conservation easement for 978-acre Sonoma Mountain ranch

Scenic hillsides, rolling grasslands and oak woodlands on a large swath of Sonoma Mountain gained protection last week when the Sonoma County Agricultural Preservation and Open Space District approved $3.1 million in public funds to partner with the Sonoma Land Trust in acquiring a conservation easement over the Donnell Ranch. The Land Trust will contribute about $720,000 toward the acquisition.

Known as the Gravelly Lake conservation easement, owned by the Bruce Donnell family, the 978-acre property is located at the top and eastern-facing hillsides of southern Sonoma Mountain, and includes several intermittent headwater streams draining to San Pablo Bay, two sag ponds along the Rogers Creek Fault, and significant natural habitat that will allow for wildlife movement between Sonoma Mountain and the baylands.

“The Donnell Ranch is one of the most scenic properties in our region – it’s a gateway to our county,” said 1st District Supervisor Susan Gorin who, along with her four fellow county supervisors, comprise the board of the open space district.

The ranch rises from the southern Sonoma Valley floor, reaching an elevation of almost 1,000 feet above sea level, to provide an open backdrop to the southwest end of Sonoma Valley. The iconic view of rolling grasslands and oak woodlands is visible from Sonoma Valley, along Highways 121, 12 and 37, as well as the adjacent Tolay Lake Regional Park.

Aside from some irrigation, fencing and a few ranch roads, there are no structures or any other improvements on the property. Approximately 67 acres of planted vineyard are located at the lower elevations, and much of the rest of the property is used for cattle grazing. While the easement protects the scenic and natural resources on the property, it also allows for recreational and educational opportunities, residential use, grazing and agricultural cultivation.

The ranch is adjacent to Tolay Lake Regional Park and, combined with the protection of the Gravelly Lake easement, the two properties help to form a system of protected land along southern Sonoma Mountain that spans into the wetland areas of the San Pablo Bay National Wildlife Refuge.

“Thanks to landowners like the Donnell Family and the partnership between Sonoma Land Trust and the Ag & Open Space District, the scenic backdrop to Tolay Lake Regional Park will be protected forever,” said Wendy Eliot, Sonoma Land Trust conservation director.