At Mana Meadows, there are two sources of water. 1) At random places, small concrete tanks have been built by locals like one you could see in one of the photos above with lake in it. 2) Water stream which accompanies through out the trek. However, if you camp on Mana Meadows, you have to descend to make the water available. It is however advisable to carry drinking water along since many are not used to these types of adventures, now-a-days. 
In Paprung village, there is however no issues with respect to water.
