Last spring we evaluated a failing parking lot off New Circle Road. The asphalt had alligator cracking everywhere. The owner assumed it was just old age. The cores told a different story. The limestone subgrade was saturated. The base course had fines migrating into the stone. Classic karst drainage failure. In Lexington, flexible pavement design cannot rely on textbook assumptions. The Inner Bluegrass has weathered limestone with sinkholes, variable rockhead, and perched water tables. A pavement is only as good as its subgrade. We learned that lesson on dozens of projects here. That is why our team starts every CBR road investigation with a detailed subgrade profile. Then we layer the structure properly. No shortcuts. You need the right asphalt thickness. You need clean drainage paths. In this region, ignoring the geology means you will repave in five years.
In the Bluegrass karst, the best asphalt mix design fails if the subgrade drainage is an afterthought.
