Water used to be a dangerous drink. We take clean water, called fresh water, for granted, and it seems natural that we have the right to drink safe water. However, it is only recently that ordinary households have had access to good quality water, and in the days when water purification facilities were not available, water was a dangerous drink.
Only about 200 years ago, alcoholic beverages were safer than water. (Alcoholic beverages were mainly beer, wine, spirits, and cider.)
Since there was no water purification system in those days, if you wanted to drink water, you had to drink directly from contaminated rivers, lakes, or springs. This led to many cases of food poisoning and disease.
In contrast, alcoholic beverages were considerably safer than water because (1) they were originally free of bacteria due to heat and microbiological processing and (2) alcohol has a sterilizing effect and is suitable for preservation. Children also drank alcoholic beverages very commonly. Pirates often drank alcohol because they carried alcoholic beverages on board their ships that did not spoil easily. During long voyages, water would spoil.
Cholera is a disease transmitted by consuming food or drink contaminated with the cholera bacteria. The feces of infected people contained the cholera bacteria. The sewage leaked from the sewage pipes that carried the excrement and got into the drinking water, which was then drunk by many city dwellers, spreading the disease.
As is well known, tap water today contains chlorine to prevent pathogens such as cholera from growing in the water pipes.
Surprisingly, Rome, which flourished some 2,000 years ago, had a complex water management system that efficiently stored and supplied water via nine aqueducts, cisterns, public fountains, and public baths. However, as Rome declined due to the invasion of foreign tribes, the aqueducts and other structures equipped with water supply systems were destroyed.
Finally, the Roman people began to rely on polluted well water and river water that also flowed into the sewers, and civilization was lost.