After 20-plus years of planning, a Highway 156 redesign is set to begin.

Highway 156, an east-west corridor between highways 1 and 101 from Prunedale to Castroville, was built in 1941 and hasn’t changed much since. That’s despite an increase in tourist traffic that frequently leads to bumper-to-bumper snarls, especially on summer weekends.

Plans to alleviate traffic backups began in 1997 – the vision is to expand the highway to four lanes, with two lanes going each way – and Caltrans’ environmental impact report for the project was approved in 2013.

The estimated cost of the work has proved a hindrance since then (about $400 million, pre-Covid inflation levels), but some progress is being made: On May 25, the County Planning Commission will consider approving the reconstruction of the intersection of Castroville Boulevard and Highway 156 – the only signalized intersection in the corridor – with three off-highway roundabouts and a bridge over the existing road.

Though Caltrans is the lead agency for the project, the Transportation Agency for Monterey County is contributing about $29 million of state funds it has banked, as well about $400,000 generated from Measure X. TAMC Executive Director Todd Muck says those funds come from “years of saving up” in anticipation, but that funding the remainder of the corridor transformation is still a question that has not been answered.

“We’re continuing to look for opportunities to fund any component of the project,” Muck says. “We’re trying to chip away at it.”

This comes after TAMC, in 2017, completed a study as to whether making the highway a toll road could close the funding gap for future segments. The result showed an estimated $75 million shortfall to fund the remaining project, so TAMC’s board tabled the idea indefinitely.

Caltrans spokesperson Kevin Drabinski says that, pending approval, the project would begin construction next spring, and wrap up in early 2025, but that it won’t require much disruption of traffic on the existing highway as the project will be building entirely new infrastructure.

While Drabinski says the construction will cost about $24 million, Muck says that TAMC’s cost estimates for the project – from conception to completion – have continually risen in the last few years. “Every number you publish is almost wrong the minute you say it,” Muck says. “When projects take a long time to get built, these numbers start to stretch.”