Public health took a huge step forward in the late 19th Century with the rediscovery of the fact that keeping drinking water and sewage separate eliminated many killer diseases, a fact that the old Roman Republic had noticed when it built sewers to take effluent downstream of the city and brought in decent water through aqueducts from the mountains; engineering made people a lot healthier.
But while the city of Rome had decent drinking water more than 2000 years ago, an unpolluted river on its doorstep and its sewage dumped safely, the same cannot be said for Harare in the early 21st Century.
Five people died of diarrhoeal diseases in the city in the first week of the month, almost half the national total.
Water supplies remain intermittent and far too many people rely on shared unprotected wells. The terrible cholera epidemic of three years ago started in a single well, we need to remember, and spread because other wells were then contaminated by raw sewage.
A recent task force set up by Harare City Council has had no effect yet, although it could have almost immediately introduced and enforced a fair rationing scheme ensuring that residents did not waste water and that everyone received reasonable supplies much of the time.
Bulawayo, with far stricter rationing than Harare would ever need, manages to keep that city healthy so there is no excuse. We still see people hosing down their cars and watering their gardens in some suburbs while other suburbs go dry.
We continue to believe that it should be possible to give all Harare consumers uninterrupted water supplies if these same consumers do not waste water, and that means enforcing the bans on hosepipes, on watering gardens and on washing cars without a bucket. Although the city council talks a lot about its shortfalls, it does actually treat and pump a lot of treated water every day.
Now public health experts are concerned that intermittent supplies allow contamination of water in pipes; the leaks that concern water engineers work both ways.
When the water is flowing much is wasted. When the water is not flowing contaminated ground water can seep in, no doubt the same contaminated ground water that some draw though their wells. Some boreholes have also been found to be unsafe for the same reason.
Clearly we need, besides having our water supplies fixed, a new public health campaign. Wells are needed, otherwise many will not have any water.
But water required for drinking or cooking needs to be treated. Chlorine bleach is cheap and effective, with a cupful killing germs in a 20 litre drum.
Boiling does the job just as well.
With concerns that some piped supplies may be contaminated, there is obviously need to expand the testing programme.
We agree, because we have done some tests ourselves, that what is in the city reservoirs is safe, if not always clean, but the council now needs to take samples at the end of is distribution systems to ensure that what is delivered to houses is also safe.
The council also needs to test at least the public boreholes; some of the schools that use borehole water routinely send samples for testing to ensure that what they pump is safe and remains safe so there is no reason why the council cannot do the same.
Clearly work must be accelerated on the other side of the engineering equation, with sewers fixed up where they are leaking or are blocked.
It can take days for the council to clear a blocked sewer and often those in the vicinity need to buy their own chlorine granules to decontaminate the sludge that covers the ground. A far more instant reaction is required. We have suggested before that cutting off water supplies, or using the sheriff to seize property for auction to pay arrears, is neither effective nor fair.
Obviously people must pay, but garnishee orders on income seem the way forward.
The civil courts use this system in other areas and there is no need to assume it would be ineffective in settling many city council bills. Auctions, in any case, rarely provide enough money.
The city council is supposed to be taking the whole problem of water and sewage disposal more seriously. What we now need is action, not empty gestures. People are dying.