Transportation officials are working on the design of a 4.9-mile-long twin tunnel to improve the 710 Freeway.   At a projected cost of $5.4 billion, the planned 710 Freeway modification plan is considered a compromise solution that would close the gap in the region’s freeway network.

bored_tunnel
Bored tunnels: 4.2 miles long with single entrance and exit on each end.
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Cut-and-cover sections: Transition four lanes of surface traffic into double-decker tunnels.

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