In December of 2004 a friend and I traveled down to the Bonne Carré Spillway at Norco, Louisiana. Our purpose was to photograph the recently restored TN&O/SP steam locomotive #745. It was making a break-in and testing run, and it would be traveling over the Kansas City Southern trestle that crosses the spillway.

While waiting, we heard an air horn behind us and turning around, we saw a Canadian National train heading south on the CN’s (formerly Illinois Central) trestle which also crosses the spillway. I spied a large cargo ship just beyond in the Mississippi River, and captured both of these as they were passing each other. Looking closely, you can see the weir that is at the entrance to the spillway. It’s that dark colored “wall” behind the trestle, viewable between the trestle bents.

Wikipedia has a good description of the spillway: The Bonne Carré Spillway is a flood control operation in the Lower Mississippi Valley. Located in St. Charles Parish, Louisiana, about 12 miles west of New Orleans, it allows floodwaters from the Mississippi River to flow into Lake Pontchartrain and thence into the Gulf of Mexico. The spillway was constructed between 1929 and 1931.

Adding to this: The control structure is a 1-1/2 mile long concrete and wooden weir parallel to the edge of the river. The concrete forms the support piers, and large wooden beams (needles) create a wall. The needles can be lifted out to allow water to flow into the spillway, removing as many as needed to control the flow. It’s quite interesting, and you can read more by following the link above.