Mumbai: Megastar Amitabh Bachchan on Tuesday said water scarcity is a massive problem at hand and one must start taking steps towards its conservation immediately.

Bachchan said the crisis needs "more serious" attention from one and all.

"It's important to start sharing this information, talk to our children, tell them what's going to happen in the years to come and slowly inculcate some kind of a culture in them which goes along with the thinking of noble people.

"It's (water) a massive problem. It's like a disaster that has already started to happen..." the 76-year-old star said.

The actor was speaking at the launch of the Mission Paani campaign in the presence of Nitin Gadkari, Minister of Road Transport & Highways here.

Bachchan is the ambassador of Mission Paani, a water conservation awareness campaign which aims to educate the masses.

"The landmass erosion problem is so evident. We used to stay at a hotel in Goa for film shoots where there was a lovely beach. But a couple of years ago when I went there, there was no beach left. It has come right up to the hotel.

"The erosion is taking place slowly and it's disheartening to see that happening. Somewhere all of us have to start doing things to preserve the water system," he added.

The actor said people in urban India "need to set an example for people who are less privileged".

"We can start doing that by little things like conserving water, for example not keep the shower running and use it only when required.