Water Safe is an extension of the existing Water Industry Approved Plumber Scheme. To become a WIAP you need to have passed the water regs course. The benefit of being part of the WIAP/Water Safe scheme is the ability to carry out notifiable works without having to give the statutory notice and being inspected by the water inspector.
At the moment the water regulations are very poorly policed and installations are carried out without being notified or inspected but OFWAT are concerned about the regular blatant breaches of the regulations and subsequent risk to public health. For quite some time there has been a levy on water bills that has been put into a fund that is supposed to be used to increase compliance with and public awareness of the regulations. This fund has been slowly inreasing and lain unused for quite some time. The water undertakings were told that unless this money was used to promote public awareness of the necessity of following the water regs they would have to give the money back. We all know that returniung money is anathema to any public body, hence the creation of Water safe. It may all come to nothing but it can't hurt to be in at the beginning.