By Ian Schwartz

SACRAMENTO (CBS13) — Give yourself extra time if you plan on driving over a busy Sacramento bridge as crews begin levee work.

The H Street bridge over the American River went from four lanes down to two starting on Friday night.

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The Army Corps of Engineers is working to strengthen the levee the bridge sits on.

“We’re trying to prevent water from flooding all of Sacramento,” said spokesman Todd Plain.

They are drilling 60 feet down into the levee and filling it with a cement mixture to prevent water from seeping through. The levee under the H Street bridge is one of 30 sites they’ve been working on for 15 years.

To drill down into the levee, crews need access to the bridge, and will close parts of it each night for a month. While cars will be slowed by lane closures, pedestrians won’t have access after 8 p.m.

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Lamarien Collier uses the bridge to get to and from Sacramento State.

“It’s an easy route to ride your bike or walk,” he said.

For a month, he’ll need to find an alternate route at night.

Plain says the project may be a pain for some, but as a native Sacramentan, he also knows living near a river brings big risks.

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“I kinda take it personally that I want to make sure everybody knows this is an issue,” he said. “I’m sorry that the trails are blocked, detoured for a while, but it’s very important work. Even though we’re in a drought, this has to happen.”