Greene County, Missouri's sinkhole regulations

Greene County is located in the Missouri Ozarks, a karst region characterized by thin stony soils overlying carbonate limestone. The area has many sinkholes, losing streams, caves and springs. The unincorporated area of Greene County contains the urban fringe around Springfield, Missouri's third largest city. Along with all of southwest Missouri, Springfield and Greene County are growing at a rapid pace. In 1994, the total population of the county was estimated to be approximately 220,000, of which 53,400 were residents of the unincorporated areas. Total population is conservatively estimated to increase to 275,000 by the year 2020. Rapid growth has created pressure for development of environmentally sensitive areas such as sinkholes. In an effort to balance development needs with environmental concerns, Greene County adopted regulations for sinkhole areas in 1991. The regulations prohibit development in sinkholes without approval of a plan by the county. A policy was concurrently developed to serve as a guide for development around sinkhole areas. This paper examines our experiences, successes, and failures in applying the regulations and policy over the past five years. It also describes the practical ways in which we deal with such problems as defining limits of sinkholes for regulatory purposes, establishing regulatory flooding elevations, siting on-site wastewater systems, and addressing urban runoff water quality. Examples of specific applications will be reviewed, strengths and weaknesses of our approach will be discussed, and needs for additional research will be presented.