The Sruh Croppa River normally drains into its bed just south of the bridge on the Marlbank road (see Marble Arch Karst: Sruh Croppa Cave site record). In periods of sustained and exceptionally heavy rainfall, the volume of water exceeds the drainage capacity of the open joints in the river bed and overruns them, flooding into the dry valley to the north and eventually roaring over a 10m cliff into the hollow called Cat's Hole, 400m north of the road, where it drains into the ground. In highest flood conditions the river passes even further to the north and east but this is an uncommon event.
The river is part of the Marble Arch Caves system's catchment, as proved by dye testing.
The drainage strategies of the rivers entering the Marble Arch system are all different and a significant part of its importance.
Cat's Hole is accessible and at present there appear to be no threats to the site.