The karst development occurs whenever acidic water starts to break down the surface bedrock near its cracks, or bedding planes.
As the bedrock continues to break down, its cracks tend to get bigger.
As time goes on, these fractures will become wider, and eventually a drainage system may start to form below the surface. If this underground drainage system does form, it will speed up the development of karst features due to the fact that more water will be able to flow through the area.