Nighttime commuters traveling Highway 17 between the Summit and Glenwood Drive have noticed some changes.

Armed with $8.2 million, Caltrans and Pavex have been working since last March to make that stretch of road safer. Crews are out there roughly from 8 p.m. to 5 a.m. Sunday through Thursday, weather permitting.

I went out Wednesday night to see what was going on. Here is what I learned.

The part of the project that involved shearing off part of the mountain to widen the right-hand shoulder from 1 foot to 8 feet is finished. A retaining wall was installed to help keep the mountain in place.

The added shoulder space serves multiple purposes. It gives motorists more line of sight around the curves, making it easier for them to stop in time if they see brake lights ahead.

The extra room also helps give vehicles going out of control or trying to avoid a collision more wriggle room, before smacking into the base of the wall, which is designed to deflect vehicles.

The wider shoulder also gives emergency personnel more room to get to wrecks. Previously, motorists would have had to split apart, allowing space down the middle of the highway for emergency vehicles.

Now, workers are tearing down the concrete median barrier to install a new drainage system. It will consist of dropping ducts into the ground and paving using porous asphalt, which will allow rainwater to soak through. The current drainage system features holes at the bottom of the median. During rainy days, the holes get clogged, allowing water to pool and making travel along the highway more difficult.

The project is expected to wrap up this summer, weather permitting. It's about 40 days ahead of schedule and around $800,000 under budget because of modifications to the project that occurred along the way.

Until recently, the dry winter weather had allowed a brisk pace on the project.

"The good weather does help with getting more work done during the winter," said Jennifer Wilson, resident engineer for Caltrans. "However, even when there is a chance of rain on Highway 17 at night, we generally chose not to work because of safety for both the workers and the traveling public. So, this winter, there have been lots of frustrated nights where we decide to call off the work and the weather turns out to be OK."

"Seventy-five percent of traffic collisions occur in wet weather," said Eli Mowbray, project manager for Pavex.

And narrowing down travel lanes when visibility and maneuverability are limited by the weather is unsafe, he said. Some motorists have a difficult time following directions even when the roads are clear and dry, he added.

Wilson and Mowbray recalled one night when they had used cones to reconfigure the travel path so that both directions of traffic would use the southbound lanes. A motorist missed the posted signs and drove on the wrong said of the cones. Lucky for him, they said, there was an accident further down the road, oncoming traffic was not getting through and he didn't wind up hitting anyone.

Safety is the top priority. Crews must wear yellow reflective gear and hard hats. A movable barrier, made of rebar and concrete, is all there is to protect workers. "The movable wall has definitely been hit, but that is what it is designed to do," Wilson said. So far, there have been no worker injuries due to a motorist, and Wilson wants to keep it that way.

She urged motorists to obey 25 mph signs posted in the work area.

The California Highway Patrol reports making numerous DUI arrests and has written many speeding tickets in the construction area. Caltrans construction areas are double fine zones. So, expect to pay twice the normal fine for speeding and driving while impaired.

Street Smarts is written by Ramona Turner and appears Mondays. Read the daily blog at www.santacruzlive.com/blogs/streetsmarts. If you have a transportation question or idea, send it to streetsmarts@santacruzsentinel.com. Be sure to include a name, city of residence and daytime telephone number.