I worked for Anglian Water pre and post privatisation and yes the industry did need investment, but I asked the question at various forums in the lead up "who come first customer or shareholder?" they didn't answer me.
I know that shareholders are not generally hugely wealthy top hatted landed gentry but are companies that are looking after and investing our pensions, but I have always felt uneasy about selling off essential services such as water, electricity etc.
I sort of get competition but as an Anglian Water customer I do not have a choice of getting my water from Severn Trent…so in effect there is no competition.
Its all well and good fining companies for polluting rivers with sewage, but all that happens is they pass on the costs of this fine to us the poor old customer. So we end up paying for their incompetence.