SAN FRANCISCO  Mayor Gavin Newsom is competitive about many things, garbage included. When the city found out a few weeks ago that it was keeping 70 percent of its disposable waste out of local landfills, he embraced the statistic the way other mayors embrace winning sports teams, improved test scores or declining crime rates.

But the city wants more.

So Mr. Newsom will soon be sending the city’s Board of Supervisors a proposal that would make the recycling of cans, bottles, paper, yard waste and food scraps mandatory instead of voluntary, on the pain of having garbage pickups suspended.

“Without that, we don’t think we can get to 75 percent,” the mayor said of the proposal. His aides said it stood a good chance of passing.

How does he describe his fixation with recycling dominance? “It’s purposefulness that could otherwise be construed as ego,” Mr. Newsom said. “You want to be the greatest city. You want to be the leading city. You want to be on the cutting edge. I’m very intense about it.”