Steel railings are installed on the southbound lane of the causeway in March 2019. The rails are aimed at reducing overboard accidents are currently being constructed. 

Crews have installed a mile of new railings at the St. Tammany Parish end of the southbound span of the Lake Pontchartrain Causeway, with teams working overnight to avoid traffic interruptions amid the safety upgrades, officials said Friday.

The new steel railing is being added to the outer, or right-hand, side of the bridge to help prevent crashes involving vehicles going into the lake. Causeway General Manager Carlton Dufrechou said work on the inner side should start this fall.

Since 1994, 17 "overboard" crashes have happened on the bridge, resulting in 13 fatalities. Sixteen of them occurred on the southbound span, which is the older of the two and has a lower guardrail. Its barrier is just 25 inches high, 6 inches lower than on the northbound span.

The project is adding new steel guardrails on top of the existing concrete barriers.

Drivers should expect lane closures as crews install the new features, which are part of a nearly $100 million program of safety enhancements that also includes adding extended shoulders that will triple the almost 24-mile-long bridge's emergency stopping space.

The first shoulder area, located a few miles from the south shore, is expected to open Aug. 1. There will be 12 emergency stopping areas in all, and they are expected to be completed at six-week intervals.

The shoulders will be 1,000 feet long and about 15 feet wide. Six will be placed on the outside of each span. Officials hope they will offer motorists a safe place to pull off the road if they experience engine trouble or other problems.

Drivers without toll tags now pay $5 to cross the Causeway in the southbound direction, a $2 hike that went into effect two years ago in order to pay for the safety improvements.

Dufrechou said the work involves “truly the two most significant safety enhancements on the bridge in 50 years.” 

Causeway officials will be announcing lane closures on a weekly basis.

From Tuesday through Friday next week, the right-hand lane of the southbound span will be closed from 7:30 p.m. to 4:30 a.m. beginning at the toll plaza and continuing for three miles as crews install the new safety railing.

Follow Sara Pagones on Twitter, @spagonesadvocat.