Karst refers to carbonate rocks, such as limestone, that have been dissolved by water to form features like sinkholes, caverns, fractures, and disappearing streams and springs and are Karst areas are known to have direct pathways for surface water to infiltrate into the aquifer, making them vulnerable to surface contamination. In areas with karst geology, as much as 80% of wells can have coliform problems due to the direct infiltration of surface water into the aquifer. This contamination can be caused by factors such as livestock activities in the area. Therefore, the presence of karst can significantly affect the quality of groundwater by increasing the risk of contamination.

Figure 1 shows karst areas of the continental United States having sinkholes in soluble rocks (carbonates and evaporites), as well as insoluble volcanic rocks that contain sinkholes. If your water well is located in a karst area, there are a few important things to know:

Potential contamination: Karst areas are characterized by the presence of fractures, fissures, and openings in the rock, which can provide direct conduits for water to flow into your well from other sources, such as farms or livestock. This means that there is a higher risk of contamination in your well water.

Continuous Disinfection: Due to the potential for contamination, it is recommended to have continuous disinfection in your well. This can be achieved through methods such as adding a UV ultraviolet light unit or using other alternative approaches to ensure the safety of your well water.

Impact on Nearby Wells: In karst areas, the proximity of wells to each other can also impact the water quality. If nearby wells are not properly constructed or maintained, they can become potential sources of contamination and affect the direction of groundwater flow.

Regular Testing: Remember to regularly test your well water to ensure its quality and take appropriate actions if any issues are detected.

Consultation with Professionals: It is advisable to consult with professionals in your area who have expertise in dealing with karst areas and well water. They can provide guidance on the specific measures you can take to protect your well and ensure the safety of your water supply.