RICHMOND -- A proposed hillside development of three luxury houses was unanimously rejected by the City Council on Tuesday.

The applicant, William R. Randolph III, appealed an earlier decision by the city's Planning Commission denying his project in the El Sobrante Valley area because of concerns about unstable soil, water runoff and inadequate roadways. The city's Planning Department supported the plan, saying the development would include provisions to improve conditions for existing homes by shoring up surrounding infrastructure.

But the council was unmoved.

"This is a disaster waiting to happen," Councilman Nat Bates said.

The decision followed more than 90 minutes of debate, including reports by the city's planning staff and consultants as well as residents in the community surrounding Knobcone Court who opposed the application.

Planning Director Richard Mitchell acknowledged that roads and water drainage were a problem around the site but that they were not good reasons to reject further development.

"All these issues will be addressed," Mitchell said. "They actually would be better off with some development."

Tuesday's decision appears to put an end to a decade-long effort to further develop the hillside.

The plan, far smaller than early proposals in 2004, was to divide 2.85 acres into four parcels -- three large houses and a detention basin for storm runoff. No square-foot sizes for the houses were proposed Tuesday, but the lots would have been 13,000 to 16,000 square feet.

Residents said they already deal with deteriorating, narrow roads and storm runoff improperly channeled into their homes. They said the proposed development lacked specifics about how further impacts and slide dangers would be addressed, and lacked concrete assurances that issues such as water pressure and sewer drainage would not be impaired.

"There are too many problems left unsolved" by the plan, said Eleanor Loynd, co-chair of the El Sobrante Valley Zoning and Advisory Committee, a neighborhood group. "Too many ideas and plans that could go wrong."

Randolph appealed in vain to the council, noting that the proposal had been scaled back to assuage concerns and saying it would have more benefits than negatives. But Randolph seemed to see early on that he had no support on the council.

"This has been a long, arduous process," he said.

Contact Robert Rogers at 510-262-2726 or rrogers@bayareanewsgroup.com and follow Twitter.com/roberthrogers.