Botlivec is a typical karst spring characteristic of the shallow karst of Bela krajina. The water flows from the cave on the edge of the Lahinja valley and flows into the river after 30 m. The source cave with a large entrance opens under a rock wall. After three meters, the ceiling drops and the tunnel along the stream narrows. The cave is accessible in a length of 7 m. At the bottom of the cave is gravel and clay debris.

At medium water levels, the stream has a flow of about 1 l/s and dries up only during prolonged drought. The water hinterland of the stream is represented by Velika loza, a sinkhole plain between Gradac and Geršiči village. Until the construction of the water supply system in 1971, Botlivec was an important local source for Gradac and Geršiči. Around 1936, a concrete barrier was built at the entrance to the cave to hold water, and a trough in front of the cave. Older residents remember that there were organized gatherings and festivities before the spring for the church holidays.