NULL Of 254 counties in the Lone Star State, Dimmit County ranks 31st in terms of size (1,334 square miles). Dimmit County is in Rio Grande Plains Texas. The total value of roughly 1,000 acres of riverfront homes and property recently listed for sale in Texas's Dimmit County was almost $2 million. Browse all waterfront property for sale in Dimmit County on the Land Network to find the marina, lakefront and other recreational property that meets your needs, from waterside land perfect as a retirement investment to existing residential waterfront land and property for hunting, fishing and other outdoor-recreation pursuits! The most common type of land for sale by combined acreage in Dimmit County is ranches.