Headlights on and the sun setting to the west, cars, pickups and 18-wheelers inched along La. 70, still wet from a passed rainstorm on a dreary Thursday night.

The long, slow path ahead was marked by the parade of red tail lights rising up the Sunshine Bridge, covered by a gray shroud and fading in the evening light.

The rush hour jam up the bridge’s western approach in the northwestern tip of St. James Parish already was more than two and a half hours long by 7 p.m. It wouldn’t clear until nearly 7:45 p.m.

The weekday rush-hour traffic, tough in early morning and worse in the evening, has become a source of frustration for many of the 22,000 drivers who daily use the bridge once dubbed a “bridge to nowhere” when it was built in the early 1960s by then-Gov. Jimmie Davis. It now heads to somewhere, taking workers to expanding industrial facilities in the parishes downriver from Baton Rouge. These added commuters are being squeezed onto a bridge that has been out of full commission since March, when the state shut down two lanes for repairs.

Some say rush-hour traffic backs up to a four-way stop sign at the intersection of La. 70 and La. 3089, nearly three miles from the bridge’s west bank side, with similar delays on the east bank.

“I hate this bridge, especially at this point. I hate it,” said Cynthia Scott, of Donaldsonville, who commutes over it daily to Baton Rouge for work.

She and her husband, Emile, had stopped by a gas station near the bridge at about 7:20 p.m., after Cynthia finished a nearly 2½ -half hour drive from Baton Rouge that included fighting through a minor bridge crash.

Begun in February, a $25.1 million state Department of Transportation and Development project is rehabilitating the bridge first opened in October 1964. The four-lane Mississippi River bridge has been reduced to two lanes as contractors sandblast, repair and repaint the cantilever bridge’s metal truss spans, DOTD officials have said. The bridge was last painted in 1980.

Traffic has been consolidated to one lane in each direction since March 19.

Along with other major projects underway along the river, the closure has coincided with CF Industries’ $2.1 billion expansion of its nitrogen complex near Donaldsonville, announced in early November 2012 and started in mid-2013.

The projects are putting even more workers on the roads and over the bridge, boosting rush hour as shifts begin and end. CF’s Ascension Parish complex, which is the largest in North America and is about a mile and a half from the bridge, draws 2,000 temporary workers per day and will hit a peak of 2,500 workers later this year, company officials have said.

CF Industries is staggering workers’ departure times between 3:30 p.m. and 7 p.m. daily to minimize traffic impacts, said Brad Lambert, a company spokesman.

The bridge rehabilitation and the CF expansion are both expected to be finished in mid-2016, officials have said.

Until then, the lane closures are here to stay. “The configuration must be in place to allow space for crews and equipment and give crews a buffer zone between where they’re working and drivers are crossing the bridge,” said Dustin Annison, DOTD spokesman.

The 35 to 40 North Star Painting Co. workers on the bridge use the two eastbound lanes to store large trailers that recycle sandblasting material, trucks and other equipment, as well as to reach the bridge’s cage-like superstructure, said Michael Mihas, North Star’s safety director.

In the section where North Star is painting, the trusses are covered on three sides with shrouds while corrugated metal sheeting hangs beneath the trusses but above flowing traffic. Mihas said the shrouds and sheeting catch falling debris and paint. Concrete barriers separate the two lanes of moving traffic from the two lanes used by North Star.

The overall effect is that drivers, perched high over the river, move through what feels like a dimly lit, narrow tunnel along lanes with no shoulders in the face of oncoming traffic.

“You know, they’ve got the tarps over it. If it’s foggy maybe a little bit, I find it a little nerve wracking,” said Danny Craft, 47, an engineer from Baton Rouge who commutes to the Napoleonville area for work.

Craft said the bridge delays him about 20 to 30 minutes in the morning and 45 minutes to an hour in the afternoon. Accidents make it worse.

“I find that if something does happen on the bridge, it just doesn’t look like there’s a good way to deal with it,” he said.

Johnnie Balfantz, Ascension Parish schools spokesman, said minimal school bus traffic contends with the bridge, but several hundred employees at Donaldsonville-area schools live on the east bank and cross the bridge each morning. The School Board office is also in Donaldsonville.

He said bridge accidents can force teachers and other school employees south to the Veterans Memorial Bridge near Gramercy to reach Donaldsonville, a trip 30 minutes out of their way.

Balfantz said enough employees get to school to monitor classes and avoid cancellations until teachers arrive.

“So it has not been that kind of issue, but it certainly has been pain,” he said.

St. James Parish Sheriff Willy Martin Jr. said sometimes deputies push wrecked cars down the bridge with their patrol cars. But other times, especially if there is a crash near the top of the bridge, a tow truck must back up the wrong lane, against the direction of traffic, so wrecked vehicles can be removed.“It becomes a time-consuming thing if it comes down to that,” he said.

Martin said deputies will direct traffic to the Veterans Memorial Bridge if a wreck will take a long time to clear.

Some drivers have questioned the timing of the bridge project, suggesting the repair job should have been delayed in light of CF Industries’ expansion or at least adjusted so all lanes would be open.

Audis Harvey, 31, a truck driver from the community of St. James, pointed out that DOTD repainted the bridge’s approaches a few years ago. He said the trusses on top of the bridge should have been done then so the approaches, which did not require major lane closures, could be done now.

The metal trusses for the bridge’s approaches are underneath the road deck, not over it.

“Some people that’s supposed to be so educated don’t have common sense. I’m serious, man,” Harvey said.

He added that traffic lights on either side of the bridge are not coordinated. If they were, it would move traffic more smoothly between the bridge and I-10.

Annison, the DOTD spokesman, said CF Industries did ask DOTD to postpone the project.

“But we could not do so due to the need to begin repairing and painting the bridge to maintain the integrity of the structure and the La. 70 corridor,” Annison said.

Lou Frey, vice president and general manager of CF’s complex, said the company had early concerns “about the overlapping timing of that project and our project,” but discussions with DOTD led to efforts to minimize “disruptive impacts.”

Rodney Mallett, another DOTD spokesman, said those changes included signs and traffic light adjustments.

Annison added that DOTD decided to do the approach spans first “because they were in need of repairs more so than the main bridge structure.”

He said the $6.2 million job began in April 2012 and ended in February 2014, when early work on the main span began.

Annison declined Friday to provide the bridge’s sufficiency rating, a measure of the bridge’s overall condition tabulated through a federal scoring system for funding eligibility.

He directed a reporter to file a public information request, which was filed about noon Friday. The rating was not immediately available.

Also, Annison said that, in addition to early light adjustments, a state trooper is controlling the light at La. 18 service road and La. 70 during peak times to allow more eastbound traffic over the bridge.

“We will continue to monitor traffic flow on La. 70 in the vicinity of the bridge and make changes, if necessary,” Annison said.

Follow David J. Mitchell on Twitter, @NewsieDave.