The Mississippi River's West Bank levee is shown near Myrtle Grove, where Louisiana hopes to build a $1.5 billion structure to divert sediment-laden water from the river, right, into a channel leading to Barataria Basin.

Even as America funded and built a giant levee system in the wake of the 1927 flood, it was recognized that the Mississippi River’s role in distributing sediment to build land at the foot of the delta would be forever changed.

Now, almost a century later, with Louisiana’s coast endangered, the understanding of the river’s role is the same. But to protect parts of the coast away from the levee system, it is widely accepted that diversion of river water — with its land-building sediments — is needed to build land along the coast.

The solution is controversial in some quarters but there is no effective alternative.

Over decades, it was also understood that large-scale diversions, at billions of dollars apiece, were too expensive for Louisiana taxpayers to fund alone. The “cornerstone of the plan” to restore coastal Louisiana, as Gov. John Bel Edwards puts it, is the Mid-Barataria Sediment Diversion. It is funded by billions set aside for coastal protection after the 2010 Gulf of Mexico oil spill.

The project has come under fire from some local governments in the region as well as Lt. Governor Billy Nungesser, a former Plaquemines Parish president. Their concerns about impacts on oyster fisheries and other assets of the region are understandable.

But we see the overall project, including millions of dollars to mitigate the effects of the diversion, as a critical component of saving our endangered coastline. As the governor says, the spill settlement must be invested in the big projects that will not otherwise be funded, and those with long-term land restoration impact.

This project is big but needed.

Our Views: Wise choices needed on the coast