I reside in an apartment complex in Basavangudi in South Bangalore.  Recently, during the rains, there was a sewage block in the corporation line in the road behind our apartment complex and the sewage water stagnated in our pipes for over 2-3 days.  As our basement walls have not been water proofed leaks took place into the basement and subsequently into the well.  The well water seems contaminated  and lot of people in the apartment have complained of stomach infections and diarrhea.  Is there any solution other than pumping the water out of the well completely? Can we do some purification of the well water?

The test results are as follows: Tests conducted at Public health Institute, Bangalore:

                MPN (Most probable no of bacteria per 100ml of water) Count :   1800
                                                                                           Differential Coliform test:  Neg
Report:  Water is not satisfactory for drinking purpose,  needs effective chlorination before use.

 Kindly suggest the apt method to ensure safe water for potable purposes?
 Any alternative other than chlorination is feasible?

Rajalakshmi
r_vvv@yahoo.com