Mayor Daniel Lurie declared a local emergency in San Francisco on Friday for the powerful El Niño that is likely to pummel California with rain and coastal flooding this winter.

The naturally occurring pattern happens every 2 to 7 years and is the most powerful climate influence on global weather patterns. This year’s El Niño is historically strong, and will bring extremely high tides as well as potentially very wet weather that could exacerbate tidal flooding. The first series of storms is expected to arrive the weekend of Halloween.

The declaration waives city contracting requirements that can slow down its ability to get equipment needed to defend the city from floodwaters, like pumps, flood barriers and generators.

“It will cut through our usual red tape so our departments can manage our critical infrastructure and that they can take action quickly,” Lurie said at a news conference at the Embarcadero.

The city plans to put temporary storm and flood barriers along the waterfront to alleviate flooding on the shoreline and perform maintenance on trees to mitigate against them falling down during strong winds, said City Administrator Carmen Chu.

Each San Francisco resident can get 10 free sandbags from the Department of Public Works. Carla Short, the director of the department, said residents whose homes haven’t flooded in the past “probably don’t need to come get sandbags.”

“We’re preparing for two different types of threats: heavy rain and wind that can flood streets, bring down trees, and disrupt power, and higher coastal water levels that we’re already seeing, that can flood low-level waterfront areas, even on a dry day,” said Mary Ellen Carroll, who runs the city’s Department of Emergency Management.

Small amounts of water had already spilled onto the Embarcadero near the officials’ news conference on Friday morning.

In Southern California, a hurricane and tropical storm this fall have already brought vicious waves to the Pacific coast, damaging homes in Long Beach and flooding streets in Newport Beach.

San Francisco is now among several local governments that have declared states of emergency due to El Niño. Gov. Gavin Newsom declared a statewide emergency in late September.

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This article originally published at San Francisco declares emergency ahead of expected wet El Niño winter.