Concrete Leveling in Smithville, MO

It stayed modest, with 947 residents as of 1950, until the Army Corps of Engineers built Smithville Dam between 1972 and 1977, impounding the Little Platte River into Smithville Lake in 1979. The lake drove rapid growth, from 5,514 residents by 2000 to 10,406 by 2020, mostly new construction on graded lots near the water. New construction near the lake and older homes closer to downtown both deal with the same clay-heavy Clay County ground, just in different ways. PolyJacks handles concrete leveling for Smithville homeowners with polyurethane foam and a free on-site estimate.

A Farm Town Until the Corps of Engineers Built a Lake

Smithville's history splits cleanly into two eras. Humphrey "Yankee" Smith settled the site in 1822, and the town that grew up around his mill: first called Smith's Mill, later shortened to Smithville when it incorporated in 1867, as recorded in Smithville's town history — stayed a small Clay County farm town for the next 130 years, with just 947 residents as of 1950. That changed when the U.S. Army Corps of Engineers authorized Smithville Dam in 1965, began construction in 1972, and completed the dam in 1977, impounding the Little Platte River into what's now Smithville Lake starting in 1979, according to the U.S. Army Corps of Engineers' Smithville Lake record. The lake turned Smithville into one of the Northland's fastest-growing towns (5,514 residents by 2000, 10,406 by 2020) with most of that growth as new construction on graded lots near the water. The older downtown, built long before the dam existed, sits on a different kind of ground entirely.

Lakeside Lots and Downtown Lots Fail Differently in Smithville

Smithville is really two jobs in one town. Out near the lake, the newer homes sit on lots that were cut and filled to make a buildable pad, often with slope, and the ground there drains toward the water instead of sitting flat. A driveway or patio on that kind of lot has two things working on it at once: fill that has not finished compacting, and a drainage path that runs downhill across or beside the slab every time it rains. Those tend to drop early, sometimes within a few years of the house being finished, and they drop on the downhill side. Closer to the old downtown the ground was never regraded for a subdivision. It has been sitting where it is since long before the dam was built, so the fill question does not apply and what moves is the Clay County clay itself, swelling wet and shrinking dry under slabs that have taken that cycle for decades. On the lake side, start by following the water: five drainage mistakes that sink a driveway.

Polyjacking vs. Mudjacking for Smithville Homeowners

Mudjacking has a long track record of lifting sunken slabs, using a heavy cement-based slurry pumped through much wider holes. It can get the job done, but that slurry's weight is a real consideration on the fresher fill soil found in a lot of Smithville's newer subdivisions, where the ground hasn't fully settled yet. Polyurethane foam weighs a small fraction of that slurry, goes in through dime-sized holes, and cures in minutes rather than days, which makes it a better match for newer construction as well as the older clay-heavy lots closer to downtown Smithville. If a particular slab calls for something other than foam, we'll say so plainly when we give you the estimate.

Why concrete settles in Smithville: the local risk data

KC Settlement Risk Index — Smithville

In Smithville, about 65.5% of Clay County's soil rates high-shrink-swell (USDA). Smithville grew roughly elevenfold after the Corps of Engineers impounded Smithville Lake (1977-1979), so most of its slabs sit on post-lake subdivision fill.

Kansas City averages about 80 freeze-thaw days a winter — 79.6 over the last 31 winters at KCI (NOAA station records, 1995–2026).

Sources: USDA SSURGO · NOAA / ACIS (KCI) · local record. See the full KC Concrete Settlement Risk Index.

Concrete leveling near Smithville

PolyJacks is your local concrete leveling contractor in Smithville — we serve Smithville and the surrounding communities: