Cover Collapse Sinkholes in Stormwater Infrastructure in the Urban Karst of Bowling Green, Kentucky: Occurrence, Mitigation, and Prevention

Cover Collapse Sinkholes in Stormwater Infrastructure in the Urban Karst of Bowling Green, Kentucky: Occurrence, Mitigation, and Prevention

Cover collapse sinkholes are an extremely common geohazard in karst terrains. These features, formed by concentrated flows of water entering the subsurface through discrete points in the epikarst, are particularly common in stormwater infrastructure in Bowling Green, KY. There are currently 787 known stormwater basins and hundreds of miles of stormwater conveyances in this fast-developing city, all of which concentrate stormwater flows over the naturally sinkhole-prone karst system. This paper reports on the occurrence of cover collapse sinkholes in stormwater infrastructure, particularly retention and detention basins, from inspections over the past 7 years and records from City-managed sinkhole repair projects, and inspections in 2026 of an additional 119 public and private stormwater basins in the City specifically to document the occurrence of cover collapse sinkholes. Sinkhole occurrence is analyzed with respect to basin type and the presence of permanent stormwater quality systems installed for compliance with local and state regulation. Stormwater injection wells are the most common point of initiation for sinkholes in Bowling Green based on the reviewed records. Results indicate that sinkhole formation in a basin is dependent on the type of basin, with those drained by stormwater injection wells being much more likely to have a sinkhole. Basins with water quality measures have a higher rate of sinkhole occurrence, and as such appear to be inappropriate in Bowling Green due to the prevalence of sinkholes in basins of this type.