I checked with a couple of residents and right now the accepted solution for removing contaminants from the water is boiling, as filters are only being offered for cold water.
It seems to me that they could benefit from a filter placed on the line that feeds the hot water tank as opposed to just a filter on each faucet/similar.
My question is: Do such filters exist? If not, or even if they do, how would one go about making such a filter economically? From a preliminary search it seems 'whole house filters' are quite prohibitively expensive, for example OP mentions here that his cost a thousand dollars. We're doing a drive to help, it'd be nice if we could make the filters ourselves, or give instructions how to, or raise money for reasonably priced filters and then partner with plumbers for installation, etc.
Update: From the wikipedia page on contaminants found in the water
- Lead
- Coliform bacteria
- Trihalomethane (THMs, a chlorine byproduct of disinfecting water)
There may be others.