Vauxhall Meriva - Water Leakage - furstmann

My car was leaking water but i could not pin point the location as everything was dry including the floor. I was filling it before every journey. Had to change headlight bulb today after changing the bulb started the engine to check if everything is o.k. when all of sudden water started to flow from a small hole very close to the belt like a fountain and drained the tank in a couple of minutes. Refilled the tank but same thing happened. Had to drive for a few miles and the heat gauge went all the way close to red lines. There is a hole on the part that is attached to the engine. I am not sure what part it is. I can only think of water pump. Water is leaking on to the belt and engine generating steam. The leaked water is clean with out any trace of oil etc. What could have caused this problem and how can i fix it? Please help!!