Annual flooding on the Mississippi River is part of life in South Louisiana
Each year, the Mississippi swells with late winter and spring rain and snowmelt, carrying sediments from the Midwest and the Great Plains down to the Gulf of Mexico. Before levees the length of the river were built to tame floods and help navigation, the swollen river would spill over into the swamps and marshes of Louisiana’s coast, building an intricate web of coastal rivers, bayous, ponds, lakes, bays, and thick, lush marshes.
The land underneath my house in Baton Rouge was built in the last 15,000 years by that annual flooding. The towns of Dulac, Dularge and Grand Isle, where I will launch from to fish in the coming days and weeks are built on land created by the great river in the last 5,000 years.
If the average annual flood is a garden hose, the floods of 2018 and 2019 are a fire hydrant that nobody can figure out how to turn off.
The Mississippi has been above the highwater mark (8 feet on the New Orleans gauge) for going on 230 days and there is no sign it will go below that mark in the coming month. While high water makes shipping more treacherous and dirties adjacent bays, the Army Corps of Engineers doesn’t act to protect New Orleans from flooding until the river gets to between 16 and 17 feet, prompting the opening of the Bonnet Carre’ Spillway, a floodgate located about 25 miles upstream that can direct about a quarter of the river’s flow into Lake Pontchartrain and take pressure off levees that protect the city.
This year, Bonnet Carre’ has been open for a record number of days–86 and counting. And it appears that number will grow to at least 95 days before its gates are shut for good. The old-timers talk about 1973 being the year the Mighty Mississippi almost broke free of its shackles. And the real old timers talk about 1927 when the river experienced unprecedented flooding. Now we have 2019 to add to the annals.
Generally, June is when the river begins to drop below flood stage and settle into its summer and fall channel, and when conditions downriver begin to change as the Gulf of Mexico’s green, saltier waters take over coastal bays southeast of New Orleans.
But this year the flood keeps pushing past and as a result silt-heavy freshwater from the Mississippi, Pearl, Atchafalaya, and Sabine Rivers has inundated coastal lakes and bays across Louisiana’s coast well into the summer. Sure, we understand summer doesn’t start until June 21 on the calendar, but once the thermometer touches 90, it’s summer. And that happened about a month and a half ago.
The muddy waters have some Louisiana anglers discouraged, assuming it’s just not worth the effort to put the boat in the water. But many have persevered, adapting to the freshwater influxes and finding speckled trout and redfish concentrated in areas adjacent to the freshwater, where there is enough salinity for them to feed on the shrimp, mullet,menhaden, and even freshwater shad, bluegill and crawfish that come with the floods. It’s far from an ideal summertime situation, but in some cases the fishing has been outstanding even in areas inundated by river water.
Often, Louisiana anglers lose sight of how adaptive the fish and animals can be. Speckled trout and redfish didn’t show up in Louisiana after levees were built along the Mississippi River. They were here long before that and live here because of the habitat, nutrients and food supplied by the river, not in spite of it. The speckled trout that have left coastal marshes and lakes close to the river to find saltier water this spring and summer will return this fall when the Gulf pushes back against the river,and the Gulf will most certainly push back. Then those fish will find areas full of vegetation, food, and new habitat.
Hopefully this year’s flood will be the catalyst for a serious examination of the way the Mississippi River is managed top-to-bottom. The strategy of narrowing the river, forcing it higher and higher through levees seems to be a failing approach in many parts of the country. Sediment is building up in areas throughout the basin, leading to reduced storage capacity during floods while areas downriver need more sediment to keep up with subsidence.
Those who make policy and folks who live and fish along the great river will have to adapt to what the present and future will bring, just like the fish residing in our favorite coastal lakes and bays have had to change over time.