This area of Texas has infamously expansive clay soils, such that buildings require specialized foundation systems designed to decouple the building from the surface layer of soil entirely and provide several inches of headroom for the clays to swell in wet weather without creating uplift pressure on the foundation. Without that, the soil will push structures upward when wet, and then leave them unsupported after drying. This leads to uneven subsidence and progressive structural failure.

When COTA was originally built, a massive subsurface drainage system was installed to mitigate this issue, but according to some even that was cut down significantly from the civil engineers' original recommendations for cost, and then when the circuit was flooded in 2015, the system was damaged and stopped being able to keep up with soil moisture levels. That's when the bumps started happening, and unfortunately they're not likely to stop without massive underground work to fully repair the drainage system. COTA is going to require expensive resurfacing every few years until that happens, or the track's financial supporters decide it's not worth the cost to maintain anymore. Without it, it will quickly become undriveable for most race cars.