Bearing witness to natural history in progress during Mobile-Tensaw Delta flooding

Jeff Dute By Jeff Dute
Follow on Twitter
on February 19, 2013 at 9:15 AM, updated February 19, 2013 at 1:09 PM

The Alabama River crested at 52 feet over the weekend, flooding nearly all of the 400-square-mile Mobile-Tensaw Delta.

At that height and the resulting expected crest today of 12.7 feet at Barry Steam Plant on the Mobile River, even lower marshes within a mile of the Mobile Bay Causeway, that in their breadth normally serve to spread and absorb high-water's impacts, are inundated by muddy, cold water.

During a tour deep inside the mid-Delta flood plain on Friday, some friends and I launched a couple of boats at Hubbard's Landing and traveled up Tensaw Lake and into Stiggins Lake.

I wanted to take them to the foot of Napp Lake where there's an old food plot carved out of the swamp long before it became part of the expansive Upper Delta Wildlife Management Area.

The plot isn't planted by the state anymore, but it and the woods road leading off of it to the north are popular jumping-off points for hunters. The road - which is known by locals simply as the High Ridge Road --runs through traditional southern swamp terrain and atop a natural levy before popping out on a wide power line more than a mile from the food plot.

The high ground is lined with mixed oak trees, smilax vine, patches of palmetto and dozens if not hundreds of other flora. The lowlands on either side harbor perennially moist gum ponds, connected by sloughs that are the arteries through which a flood consumes the swamp.

Many people believe the swamp floods from the rivers and lakes inward.

In reality, flood water from the big rivers first fills interior sloughs, ponds and creeks. When the swamp can no longer contain the rise, water begins breaching the levies from the inside, basically creating a shallow wooded lake of hundreds of thousands of acres in size.

There was enough water to easily maneuver a 22-foot bay boat through the food plot and up the road several hundred yards. The depth finder recorded more than 4 feet of water as it flowed at an estimated 5 to 6 knots through the surrounding woods and over the road.

It was probably twice that height where the levy dropped down into the swamp on either side.

I'm always excited to get out on the Delta. It really is an amazing place. Getting to enjoy it and is one of the main reasons I decided to make the Mobile-Baldwin county area my home.

Despite familiarity with the Delta fostered across 30 years while fishing and hunting out there, there's always a small sense of uneasiness residing just under the surface of my skin every time I leave the dock.

While I love the place, I have a deep respect for it because I know there are a bunch of things that can go wrong out there. 

That feeling was heightened on this day. I had never seen the water this high before.

Old high-water marks on the trees, denoting past flood heights, were gone, washed away by water that had not been this high since 1983 when the Alabama River crested at 52.10 feet.

At its highest, more than 455,000 cubic-feet-per-second of water was gushing through the Claiborne Lock and Dam on the Monroe-Clarke County line north of Perdue Hill.

Just to put that crest in context, a "normal" gauge height at Claiborne is less than 10 feet with a flow of about 3,000cfs.

Flood stage is 42 feet, but at 19 feet and rising at Claiborne, the gate at the Upper Delta WMA north of the Tensaw community in Baldwin County, is closed because swamp sloughs are already full and water is coursing across the main road.

At 21 feet rising, most of the swamp is under water. At about 36 feet, even the high ground is under several inches of water and the swamp has become a shallow lake of flowing water.

Despite what would appear to be a catastrophic event in reality is a good thing for the health of the Delta. The rushing water sweeps away rot, and in its wake as it falls, deposits millions of cubic yards of nutrient-rich soil.

The payload provides the fuel for the swamp's engine of growth until the next high water comes along and the process is repeated.

That process is what built our Delta across the millennia. It's always awe-inspiring to bear witness to this important part of natural history being made.