The British left India with a pressurized, always-on water system. Through lack of maintenance, most of that water system is no longer pressurized--the water co

The British left India with a pressurized, always-on water system. Through lack of maintenance, most of that water system is no longer pressurized--the water comes on intermittently. That leads to the common practice by water consumers of having a pump on their end to fill their local cistern. Since the originally-British water system was not maintained, it now leaks. So, unlike a pressurized water system--where leaks cause water to LEAVE the system, a non-pressurized system--as Indians now have--combined with the aforementioned pumps, makes it so leaky pipes cause outside filth to ENTER the system. Combine that with the practice of co-locating sewer lines in the same trenches as water lines, means that when the water comes on and individual pumps kick in, causes sewage water to enter the water system and be pulled into people's cisterns. That's why any Indian household like this must use reverse osmosis to make their water potable. All because the pressurized water system was allowed to go derelict.