rather than letting the untreated dirty water to go to rivers, it would be environmentally friendly to treat the waster water and use it again like the way they do here in the US so that we would not be pumping so much water from under the ground. some years ago it wasnt a big problem but now almost everyone is dependent upon the ground water system. aba paani nai na aaye pachhi bachna ta paryo ni.
kathmandu ma sewer ko system chha tara untrated sewer is directly mixed in the rivers.

its just a matter of time, i am sure the over pumping of water will have some negetive effect.