SAN FRANCISCO (CBS SF) — As the first significant rain of the season falls over the next three days in San Francisco, public works officials are asking residents to help prevent flooding by sweeping up leaves from the sidewalk.

Fewer leaves mean fewer clogged storm drains and potentially less flooding of low-lying areas, public works officials said.

KPIX WeatherCenter: Current Conditions & Forecast

The heaviest rain is expected on Friday with more than an inch expected over the weekend.

“We’re on the ground preparing for the rains, and we are ready to respond to any storm-related emergencies,” Public Works director Mohammed Nuru said in a statement. “We also are asking our residents to pitch in where they can.”

City public works crews maintain about 25,000 storm drains across San Francisco. City officials are reminding residents to put leaves and debris in green compost bins and litter in blue or black bins, rather than sweeping it in the street.

To help residents ward off potential flooding the public works department is offering residents 10 free sandbags, which are intended for properties prone to flooding.

Sandbags can be picked up from 8 a.m. to 2 p.m. Monday to Saturday at the department’s operations yard at Marin and Kansas streets.

Residents should bring proof of a San Francisco address. Sandbags are also sold at many hardware and home improvements stores.

Residents are encouraged to call 311 to report any clogged storm drains, flooding, downed trees and hanging tree limbs.

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