Not everyone needs an extensive plumbing course to know the rights and wrongs of the trade, but with all the DIY products that are for sale in various outlets, there is good information available to prevent water contamination by misconnection of sanitary and waste water from dishwashers, washing machines and such. However, the majority of people don't ask for this advice so not to seem ignorant or feel embarrassed about not know how or what is the right way to do things.
With the economic climate the way it is, the vast majority of people also cannot afford a tradesman with the correct knowledge to do the work properly. There are the unscrupulous people who pretend to be a qualified tradesman, undercut a price just to get the work and don't really care about the consequences of their actions.
Then the poor misguided home owner gets the backlash from the relevant authorities when the source of the contamination is traced back to a particular home. It's very hard to educate people that asking for advice is not showing ignorance. It would only show their concern for doing it the correct way and the people who would give that free information would be only too happy to give them without making them feel humiliated or stupid.
But that's human nature, and people only employ a tradesman when they have that spare amount of money to get the job done. I'm sure the vast majority of people would like to think that any work done to the correct standards without causing problems as rivers and streams being polluted to the degree that is being reported by the water authorities, but unfortunately it always comes down to money
- Mark Lewis