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ighway 35, known to locals on the peninsula south of San Francisco as Skyline Boulevard, is one odd bird of a road.

At its northern end, it's a full-on freeway funneling traffic to and from San Francisco. As you go south, it takes on a different character, suburban at first, then rural, winding through the forested ridges standing high above the bay shore and Silicon Valley.

At its southern end, it climbs into the Santa Cruz Mountains. Then, before it ends its 65-mile run, it narrows to a back-country road that's a good deal less than two lanes wide.

Now, this quirky Bay Area route has another distinction: It's the site of the single most expensive road repair project arising from the already legendary Winter of '16-'17.

The storms that came crashing into California starting last October have dropped 100 inches of rain or more in parts of the Santa Cruz Mountains this season. At a remote spot on Highway 35 in Santa Clara County that Caltrans identifies prosaically as Post Mile 10.5, the season's precipitation total is something like 94 inches.

The rain fell so hard and so long that on Feb. 10, the slope at Post Mile 10.5 gave way, spilling earth, trees, rocks and a roughly 50-yard-long section of pavement far down a steep mountainside. The result was a monstrous gouge in the landscape and a rebuilding project that Caltrans currently says will cost $37 million. (Two smaller slides occurred Feb. 10 just south of Post Mile 10.5; Caltrans says those will take another couple of months to completely clear and will cost $5.5 million each.)

Statewide, the agency lists 425 damage sites that will require an estimated $974 million to fix. Caltrans says local agencies face at least another $400 million in storm-related road repairs. The money to pay for all that will come mainly from the state and federal governments -- the latter partly due to a disaster declaration from the Trump administration.

L

ooking at pictures of the Highway 35/Skyline Boulevard slide immediately after it happened -- see the YouTube video above -- it's a little hard to imagine just how you'd go about putting a road back through the area. From one side of the gap, you gaze across at a chasm where a piece of pavement, complete with double-yellow lines, hangs in the air.

But we -- as a state and nation dedicated to the pursuit of happy and productive motoring -- are not in the business of letting some little thing like a collapsing mountainside shut down an otherwise perfectly fine road.

(Exhibit A for our determination to keep the roads open even when nature's not in sync with our intentions: Highway 1 through Big Sur. A 2001 Caltrans report documented 41 closures from rockslides, mudslides, mountain slides, slipouts, washouts and flooding along that section of highway between 1970 and 2000. There have been plenty of shutdowns since then, too. The winter of 2016-17 triggered several major slides and closures on the coast road -- including one involving a bridge failure near the northern end of Big Sur. Caltrans hopes to have a new span ready for use by the end of September.)

Visiting the big Highway 35 slide site last week with Bernard Walik, the Caltrans spokesman for Santa Clara County, I got to see the outline of the agency's repair plan.

"What we've done here is created an access road," Walik says, describing one lane of dirt and gravel that's been bulldozed, somehow, into the curving upper rim of the slide. "And actually, the access road we have in front of us here follows the profile of the new road -- meaning it's going to curve into the hillside."

Rebuilding the road will involve more than just realigning it, though. Engineers plan to build a massive retaining wall supported by piles driven deep into the mountainside.

How challenging will it be to get a new piece of highway to stay where Caltrans wants it to stay?

"Our geotechnology engineers (and) hydraulic engineers have determined that, looking at all the conditions of the current hillside, that the realignment with the support of the retaining wall will definitely provide a safe road for many, many decades," Walik says.

While I was there, one other person showed up to watch the small construction crew, which on this day consisted of two dump truck drivers, a front-loader operator and a spotter.

"These guys have got a pretty good job," says Art Vasquez, a retired heavy-equipment operator who arrives at the site on a motorcycle. "They've got job security. There's so much work around here."

He grew up in the area and says he can't remember anything quite like this winter's damage.

"It's a mess. It's a frickin' mess," Vasquez says as he watches the work. "I’ve been riding motorcycles here for 47 years, on fire trails and everything, but I’ve never seen it this bad."

How long will it take to fix things -- at least on Highway 35?

Caltrans says it hopes to have the realigned section of the road ready for traffic by the end of the year.

Thanks to KQED photographer Bert Johnson, here's a look at the construction site (click on any image to open a slideshow):