The safety improvements help persons using the Tammany Trace get across the busy highway by entering a long tunnel that goes below the highway. The highway itself was also re-aligned to produce a smoother S-curve. The highway in that area is intersected by several commercial/industrial driveways.
A tunnel was built under U. S. 190 in Mandeville in 2001 to handle Tammany Trace traffic going through that area. Click on the images to make them larger.
The U.S. 190 Tammany Trace tunnel in Mandeville
An official ribbon cutting for the Hwy. 59 tunnel took place on September 21, 2022, with Parish President Mike Cooper cutting the ribbon. (Photos from parish government website).
A video of the ribbon cutting is available from the WGNO website.
The new tunnel, Highway Project H.010184, was bid out by the State of Louisiana - Department of Transportation and Development (DOTD), with Meyer Engineers, Ltd. designing and providing project management for the planned Tammany Trace tunnel under LA 59.
A portion of the highway plans layout for the Tammany Trace tunnel. The tunnel is shown going from side to side at a slight angle in dark cross-hatching. West is at the top.
According to the department, the project removed the existing, dangerous at-grade crossing between the Tammany Trace and LA 59 by routing traffic on the Trace under LA 59 with a 150 foot long tunnel. The tunnel project included approach ramps, a sump pump to keep the tunnel dry, lighting, and waterproofing. An at grade crossing with LA 59 will be maintained to allow access to the Trace from LA 59.
This view, with west at the top, shows the old existing road in light outline, and the new roadway with connecting side roads in dark lines. Business driveways are seen also in light outline. Turning lanes
The old "S" Curve
Additionally, the project has improved LA 59 by straightening the existing sharp "S" curve left behind from when the Tammany Trace was a railroad.
This part of Tammany Trace is now underground
A close up of plans for the tunnel cross-section
Early equipment on site relocated overhead powerlines
This project is part of a Cooperative Endeavor Agreement (CEA) between St. Tammany Parish and LA DOTD. Overall the project may cost close to $4 million.
Here are some construction photographs taken over the past two years.
Photos by Ron Barthet and Dirk van Duym
The next several pictures are from Dec. 20, 2020
The following pictures are from April 26, 2021
Tunnel completely covered with dirt, May 15, 2021
August 23, 2021: Traffic rerouted over new pavement over tunnel
Old section of roadway barricaded off
Southern entrance ramp to tunnel to be built, tunnel to be pumped out
New roadway going over the top of the tunnel
New roadway going over the top of the tunnel
Side entrances squared off
Traffic over the smoother, wider "S" curve
October 27, 2021 Photographs
The southern entrance ramp is being walled up.
Photos from December 14, 2021
Southern entrance walls are up and there's light at the end of the tunnel
Photos from May 28, 2022 (Not officially open yet)
The Mandeville Tammany Trace Tunnel
Here are some photographs of the existing tunnel in Mandeville where Tammany Trace swoops under the busy U.S. Hwy. 190 thoroughfare.
The Rails to Trails Conservancy announced on July 19, 2017, that the Tammany Trace had won it’s annual competition for induction into the national Rail-Trail Hall of Fame. The Trace joins 30 previous Hall of Fame winners recognized for
outstanding scenic value, use, amenities, historical significance and
community value
See also:
http://www.tammanytrace.org/
