The Atchafalaya River is an alternate exit to the Gulf of Mexico. The Mississippi enters the Gulf in a classic delta: the big river splits into multiple distributaries as it flows out into the sedimentary delta it has built for itself upon reaching the Gulf. These distributaries originate as far north as the Baton Rouge area. Potentially one of the largest of these distributaries could be the Atchafalaya River. The Atchafalaya hydraulically "wants" to be the main exit for the Mississippi into the Gulf; it likely would be now if humans, starting in the 19th century, hadn't prevented nature from taking its course.
The problem with letting the river do what physics says it should is all the human infrastructure and commerce dependent on the Mississippi flowing to the Gulf as a navigable river. Let the Atchafalaya capture the Mississippi and Baton Rouge and New Orleans would be commercially landlocked. Can't let that happen, so the Army Corps of Engineers has spent vast amounts of public dollars keeping the Atchafalaya from becoming the main course of the Mississippi. All that prevents river capture from happening are a number of concrete control structures; and a lock with a 15-foot drop from the Mississippi to the Atchafalaya. It seems inevitable that in the long (or not so long) run, the Atchafalaya will get its way and become the exit for the Mississippi whether we like it or not. For a more detailed and much more literate explanation of all of this, read John McPhee's superb The Control of Nature.
This geography is a part of the rational for our decision to finish our paddle to the Gulf down the Atchafalaya, the "real" exit distributary. We also chose this route because the heavy industrial areas from Baton Rouge south were not enticing to us; dealing with tows is challenging but confronting the ocean-going tankers that travel up river as far as Baton Rouge was not something we wanted to do; New Orleans isn't very accessible to paddlers; we wanted to get to the actual open waters of the Gulf; and we wanted to end up in a place where we might easily find a ride back to a town. We found the wilder lower reaches of the Atchafalaya were a great place to paddle. Several other paddlers with experience on the Lower River had recommended the Atchafalaya as the exit of choice. To transit the Atchafalaya, leave the Mississippi main stem at river mile 303.8 and enter a channel (identified only by the mileage marker) that shortly leads to the Old River Lock.
Here is a CalTopo map of the Atchafalaya route we took to the Gulf. You can export the data as a gpx or kml file. There are other options through the Atchafalaya, but we published our route as a reminder to paddlers planning to go to New Orleans that there is a quiet and beautiful alternative which is a geologically honest way to finish the Mississippi River. Also mapped is a Lafourche Bayou route recommended by a New Orleans paddler; we aren’t familiar with it, but include it as others might be interested.
We were extremely fortunate with the weather on our trip and experienced weather related delays only a few times. You should not count on this and should not be surprised if bad weather prevents further downstream progress for periods of time. At the extreme ends of the paddling season, April or November, you might encounter ice in the water. Otherwise, the biggest weather problem is mostly related to wind. Wind speed and direction can make or break a paddling day.
We experienced head winds far more often than tail winds. We don’t know if this is typical and/or related to the time of year we were on the river. Most of the time these winds were annoying and frustrating, but did not keep us off of the water. For any particular wind speed, the geography of the river can change what it does to you. If you are paddling into a long stretch of unobstructed water, waves will have a chance to build and can be much larger than those created by the same wind blowing up a short reach. So sometimes a 10 mph wind isn’t an issue and at a different location might keep you on shore.
Sometimes the best solution for traveling on a windy day is to paddle immediately next the bank of the river. If you are lucky, the bank and its trees will provide shelter from the worst of the wind. Even if not, the waves will usually be much smaller and should you swamp or capsize, you won’t be in the middle of the river.
The second significant weather related problem is lightning. If a thunderstorm is imminent, get off of the water as fast as possible and seek shelter. If there are only woods on shore, pull your boat out of the water, tie it up and get deep into the trees. Remember that thunderstorms are often accompanied by localized high winds so be sure to secure your gear well or the river might take it away.
The final weather issue that can keep you onshore is dense fog that when present can make it impossible to see tows. We did not experience fog of this intensity, but we read trip reports that described fog so thick paddlers could not see 100 feet in any direction. Tows can be surprisingly quiet, so in dense fog, it is better to stay out of the channel.
Other weather issues that can arise include rain of varying intensities, heat, high humidity, and cold. In other words, just like the weather anywhere else.
The amount of water flowing in the river rises and falls depending on snow-melt and rainfall anywhere in its enormous basin. It goes up and down depending on manipulation of locks and dams on the Mississippi and its many tributaries. It doesn’t have to rain where you are for the river to rise. Conversely, it can be raining where you are and the water level may be dropping.
What might this mean to the river traveler? While we were on the river, it exceeded flood stage for about a week from Keithsburg to Cairo. The river rose twenty feet over the course of two days; it was not an overnight catastrophic change so it was easy not to notice that the water was rising, at least until we saw abundant floating logs and realized that the riverbanks were now underwater. We understand that high water levels on the Headwaters can make it difficult or impossible to paddle safety.
The high water brought several noticeable changes. First, riverside floodplain campsites started to disappear and it became more difficult to find a place to set up a tent. We also had to camp high enough that any further rise wouldn’t flood us out. It helped to have data from various river level websites so we could plan ahead. The river also became faster as more water was traveling downstream. It was never fast enough to make paddling a problem, but it was noticeable. Finally, massive amounts of wooden debris appeared as the river re-floated all the material that had settled out on its banks after earlier high-water episodes. This debris ranged in size from small sticks to entire trees. There was so much material coming down from the Missouri River that the Coast Guard closed the Mississippi for forty miles around St. Louis to all river traffic, including their boats. . We were putting in at the St. Louis Arch early in the morning when a Coast Guard vehicle drove up and the unit commander wouldn't let us back on the river. Friends gave us a ride twenty miles south to a put-in just out of the closure zone so we could start paddling again. We did find that since the debris was traveling as fast at the current, once you are paddling downstream, playing dodge-a-log wasn’t difficult. However, the game is tedious, a little stressful and slows you down..
For about two weeks after the water rose, the river level fell about a foot per day, eventually dropping low enough that the abundant Army Corps wing dams started to emerge. Where a few days previously we had floated over these things, we now had to paddle around them. The same thing happened with sandbars. The sandbars, though, provide terrific campsites. Falling water also prevented us from taking some of the back channels that allow you to get away from the tows. These channels often have wing dams across them and at low water the rocks stretch from shore to shore; the only way past them is to portage.
Water. We were always able to obtain drinking water from known clean sources and never drank water from the river. The river itself carries a lot of sediment for much of its length, so if you plan on filtering, you will have to deal with potential clogging. The Lower Mississippi also has a lot of runoff laced with agricultural and industrial chemical residues.
We found water sources easily in towns and local campgrounds for most of the trip. We carried fifteen liters capacity for the two of us, and this was adequate for our needs until we reached Helena. South of Helena, where water sources are more widely spaced, we also carried a couple of gallon containers of grocery store drinking water.
Food. Until St. Louis, shopping for food was not a problem. Except for the stretch between Itasca and Bemidji, and between Grand Rapids and Aitkin, there are towns with at least small grocery stores just about every day. In these towns, the grocery stores were usually within reasonable walking distance, as were many accessible bars, cafes and restaurants.
South of St. Louis, buying groceries becomes a bit more difficult as the river towns are further apart. The stores are frequently located on the outskirts of towns, several miles from the river. We were fortunate in that we were always able to find rides from helpful people we met along the way. Many of the river towns still have downtown cafes and restaurants close to the river.
Prior to departure, we mapped the location of as many riverside grocery stores as possible using Google Maps. Having this data available during the trip made daily planning a lot easier and reduced trip stress.
Riverboat casinos are legal in five Mississippi River states: Illinois, Iowa, Louisiana, Mississippi, and Missouri, and many towns south of Saint Louis have at least one. Most have AYCE buffets at very reasonable prices and are a good source of cheap calories.