Abstract: The construction of the Yingzuiyan Tunnel penetrated the vertical solution channels in the karst area and resulted in the groundwater and mud gushing into the working area. Based on the typical hydrological conditions and the observations during the construction, the counter slope drainage was used to treat the water and mud gushing conditions. This method is proved to be cost effective and the result is satisfactory.

Key words: Karst Terrain, Water and Mud Gushing, CounterSlope Drainage