More homes on San Bruno Mountain

San Bruno Mountain's Northeast Ridge, where 71 new homes will be constructed

The Brisbane City Council voted unanimously on Tuesday to approve a plan that will put 71 more homes on San Bruno Mountain’s Northeast Ridge.

In approving the plan, council members rejected a call from residents and a local environmental group to further study the impact on an endangered butterfly species, the Callippe silverspot. The nonprofit San Bruno Mountain Watch has said a new environmental impact report is needed to understand whether the homes will put the survival of that butterfly species at risk.

Council members admitted there are still unanswered questions, but said they felt comfortable with an assessment made by the U.S. Fish and Wildlife Service, the federal agency in charge of protecting endangered species. During a public hearing on the matter, U.S. Fish and Wildlife representatives told council members the development would not jeopardize survival of the butterfly species.

Council members also said they could not ignore a previous decision that gave developer Brookfield Homes the right to build on the land. The current proposal is an updated version of a plan by Brookfield to build on the Northeast Ridge. The council approved that plan in 1989, and construction went forward until 1997, when the last phase was put on hold because U.S. Fish and Wildlife had declared Callippe silverspot an endangered species.

Since then, Brookfield Homes has agreed to reduce the scope of the original project by building 80 fewer homes, and not to do any construction on a hilltop that is important for butterfly mating. It has also agreed to fund a $4 million endowment for habitat management on San Bruno Mountain, and pay $1.8 million for new public facilities.

On Feb. 1, during a public hearing on the matter, a lawyer for Brookfield said that if the council did not approve the current plan, the developer would revert back to the 1989 agreement.

The council took the threat seriously.

“I know a lot of people will not be happy because we’re not going to give you what you want,” Mayor W. Clarke Conway told residents on Tuesday night. But he said the council had only two choices: approve the current plan, or go back to the 1989 proposal. And the current plan, he said, is clearly better.