People tend to think flooding is about how close you are to a creek or the bay. That matters for storm surge, but for the everyday wet-yard problem — the soggy lawn that won’t dry out — the bigger factor is the dirt under your grass. Mobile County’s soils are mapped in detail by the USDA (the same Web Soil Survey data behind this page), and they sort the county into a wet world and a dry one. Here’s the map.
The Two Soil Worlds
Mobile County isn’t uniformly wet or uniformly dry — it’s a patchwork of two soil worlds laid over low, deeply weathered coastal ground (USDA-NRCS; Geological Survey of Alabama).
The dry world is the sandy uplands, and it’s the more common of the two. These are the well-drained Wadley sands and the reddish Bama and Malbis soils — the ones whose sandy-clay-loam subsoils give the region its “red clay” reputation, even though they actually drain moderately to well. Water moves down through this ground, so yards on it flood from surface runoff rather than a shallow water table — and where a soil like Malbis does perch water in a wet winter, it sits several feet down, not up at the root zone.
The wet world is the poorly drained flats — the Smithton soils and their low-lying neighbors, sitting on ground where a seasonal water table climbs toward the surface each winter. Threaded through it are moderately wet stream-terrace soils, like the Harleston series, that hold water at shallow depth without being true wetlands.
Most neighborhoods lean clearly toward one world or the other. But the two interfinger, and the boundary can run straight through a single subdivision — which is exactly why this is a map of odds, not a certainty about your address.
Wet-Flat Neighborhoods — Water Table First
These are the low, flat parts of the county, where poorly drained soils like the Smithton series hold a seasonal high water table within about a foot of the surface from December through April (USDA-NRCS). Yards here stay spongy for weeks and are the classic candidates for subsurface drainage.
Prichard
Prichard has the most consistent wet-soil story in the metro. USDA mapping shows the community dominated by a poorly drained, occasionally flooded soil complex — the flat, low ground holds water through the cool season, and much of it is developed on exactly the kind of soil that keeps a yard saturated. If you’re in Prichard and your yard won’t dry out in winter, a high water table is the leading suspect, and a French drain is usually the tool. Because so much of the community sits on that same wet ground, the problem tends to be the rule here rather than the exception — and that also means grading alone rarely fixes it, since there’s often no dry upland nearby to send the water toward. A drain set below the water table, paired with a planned outfall, is what does the real work.
Chickasaw
Chickasaw sits on the low ground north of the city near Prichard, so the odds lean toward the same wet-flat conditions — but we don’t have a parcel-level soil pull for it yet, so treat that as a reasonable expectation, not a certainty. If your Chickasaw yard holds water in winter, an on-site look will confirm whether it’s a water-table lot.
Sandy Uplands — Runoff, Not a Water Table
Mobile County’s single most common soils are actually well-drained sandy uplands — chiefly the Wadley series (USDA-NRCS). Neighborhoods here rarely have a water-table problem. When they hold water, the cause is on the surface: a flat spot, a downspout, or runoff from higher ground.
West Mobile
West Mobile is mostly upland — well-drained sandy loams over the reddish, sandy-clay-loam Bama subsoils and their neighbors. That ground sheds water well, so a wet yard out here is almost always a surface issue: grading, a downspout dumping in a low corner, or runoff off a driveway. The answer is usually surface yard drainage and regrading, not an expensive subsurface drain built for a water table you don’t have.
Semmes
Semmes sits on well-drained upland soils with no shallow water table. Like West Mobile, its standing-water problems are surface-driven. Installing a deep French drain here is often solving a problem the lot doesn’t have — the money is better spent on grade and downspouts.
Tillmans Corner
Tillmans Corner is largely sandy upland (the somewhat-excessively-drained Wadley soils), though it borders wet flats in spots. Most of it drains freely, so treat a wet Tillmans Corner yard as a runoff question first — but if you’re on the edge nearest the low ground, a water table isn’t off the table. Another lot-by-lot case.
Mixed Ground — Depends Where You Sit
These neighborhoods sit on both soil worlds at once — well-drained ridges laced with poorly-drained flats — so the drainage answer is genuinely lot-by-lot. The map can place you near the divide, but which side you’re on is what decides the fix.
Saraland
Saraland is a mix, and where you are in it matters. The ridges sit on well-drained upland soil, but the flats — including occasionally flooded, poorly drained ground — hold water much like the city flats do. A Saraland yard on a rise may drain fine while one a few streets over in a low pocket stays wet all winter. This is a neighborhood where the lot-by-lot look pays off.
Mobile (Midtown and West-Side Flats)
Inside the city, the pattern is ridges and flats interbedded. The higher ground drains reasonably, but the flat pockets — common through midtown and the west side — sit on poorly drained soil with the shallow winter water table. These are the yards that pond after every cool-season rain and take days to recover. The fix depends on which side of that line your lot falls on, which is why two neighbors can need different systems.
Theodore
Theodore is the clearest split of all. The uplands drain well, but the eastern, creek-side bottoms sit on very poorly drained, frequently flooded soils — some of the wettest ground in the county. Two Theodore addresses can be completely different drainage problems. On the upland side, expect a runoff-and-grading fix; down in the creek bottoms, you may be dealing with ground that stays wet even by this county’s standards, where the drainage has to be planned around where the water can realistically be sent. The soil map can place you on one side of that line or the other, but the two are different enough jobs that the address alone decides very little — the on-site look decides the rest.
Grand Bay
Grand Bay, in the far south, sits mostly on well-drained to moderately-drained soils — better than the city flats, but with lower, wetter pockets mixed in. It leans toward a runoff-and-grading story, with subsurface drainage reserved for the genuinely low spots.
Satsuma
Satsuma, north of the city near Saraland, sits on similar mixed ground — ridges that drain and flats that don’t. We don’t have a parcel-level pull specific to Satsuma yet, so treat it as mixed and confirm on site rather than assuming either way.
How to Use This Map
This map sets the odds; it doesn’t settle your yard. The reason is that soil in Mobile County changes over short distances — a poorly drained flat can sit a hundred feet from a well-drained rise — so a neighborhood-level map tells you what’s likely, not what’s certain for your address.
Use it this way:
- If you’re in a wet-flat neighborhood and your yard stays soggy through winter, you’re probably looking at a water-table problem, and a French drain is the usual fix.
- If you’re on the sandy uplands and water still pools, it’s almost certainly runoff or grading — a cheaper problem to solve, and the wrong place for a deep subsurface drain.
- If you’re on mixed ground — Saraland, the midtown flats, Theodore, Grand Bay, the neighborhood edges — the map can’t call it for you, and an on-site diagnosis is the only honest answer.
Every one of these calls comes down to the same on-site look: your grade, your soil, and where the water can be sent. The map narrows it down; the yard decides it.
