HERCULES (BCN) — A leaky pipe caused icy conditions and multiple car crashes this morning, prompting authorities to close down part of westbound state Highway 4 in unincorporated Hercules until later Saturday, a California Highway Patrol officer said.

A crash was first reported about 7:35 a.m. on westbound Highway 4 near Cummings Skyway, CHP Officer Eric Anderson said.

At least two other crashes occurred in the same area in the next hour, leading authorities to find a pipe near the Cummings Skyway overpass that was leaking water, Anderson said.

The water was freezing on the roadway and causing unsafe driving conditions, so the CHP shut down that portion of the highway while crews respond to drop sand on the lanes, he said.

Drivers are being diverted off the highway at the Cummings Skyway off-ramp, and are getting back on at the on-ramp, Anderson said.

Westbound Highway 4 was expected to stay closed until about 11:45 a.m., he said.

No one was injured in any of the crashes on the highway, he said.

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