The I Street Bridge has been a workhorse over the Sacramento River for 101 years, supporting not only cars but freight and passenger trains as well.

Now, though, officials on both sides of the river say it's obsolete and needs to be replaced.

In a joint grant application, Sacramento and West Sacramento officials have asked the federal government for $77 million to help fund a new span nearby.

If they get the money, they say, they can leave the I Street Bridge for trains, and build a sleeker crossing for cars and pedestrians. It would be designed, they say, to improve each city's connections to the river and boost upcoming redevelopment plans in the Sacramento downtown railyard.

"We need to create better access to our waterfronts," West Sacramento Mayor Christopher Cabaldon said. "The I Street Bridge is a major choke point and a safety issue."

Jerry Way, city of Sacramento public works director, said the I Street Bridge doesn't meet current design standards for bridges. Its two-lane upper deck is too narrow, pedestrian sidewalks are unsafe and there is no separate space for cyclists.

By abandoning the bridge, the city could knock down elevated approach ramps, creating open space on the river and a better link between the railyard and Old Sacramento.

The I Street Bridge itself would not be torn down. Union Pacific, which owns it, would continue to use the lower deck for freight trains. The tracks also would continue to serve as the conduit for Amtrak and Capitol Corridor passenger trains into and out of Sacramento. UP estimates that 70 to 80 trains a day traverse the bridge.

"It is an important part of Sacramento's rail infrastructure now and will continue to play an important role as we move forward," said UP spokesman Aaron Hunt.

Way said a new bridge could cost up to $150 million. An exact location has not been determined, but a likely site would be a few hundred feet north of the I Street Bridge, connecting C Street in West Sacramento to the planned Railyards Boulevard in the center of the railyard.

Officials envision a low-profile bridge that can accommodate cars, bikes, pedestrians, buses and possibly a streetcar system. The bridge would have a movable section to allow tall boats to travel through, either pivoting like the I Street Bridge or a deck that lifts.

Way said securing a federal grant also would allow the cities to apply more of their limited local transportation money to another planned Sacramento River bridge at an undetermined location south of downtown.

City officials also have begun talking about knocking down the I Street onramp to northbound Interstate 5, which acts as a wall between the downtown depot site and Old Sacramento.

Several planners from the Urban Land Institute visited the railyard last week and encouraged the city to continue exploring the idea of eliminating the ramps.

Cars traveling west on I Street would still be able to enter I-5 in the southbound direction, they said. But those wanting to head north on I-5 would have to shift to ramps at Richards Boulevard, L Street or P Street.

City officials say they will do traffic studies to determine how eliminating the I Street ramp would affect commuter traffic on adjacent streets.

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