I can't parse your first statement (there isn't any 'stripping of energy' that I can see, the apparatus is converting some of the kinetic energy in the water into plasma.) But the second statement one is exactly right, we have an existing system for extracting energy out of moving water (hydroelectric turbines). That goes through a very mechanical process of rotating machinery to generate electricity and the turbines need quite a bit of maintenance.
By stripping I meant conversion. The energy in water pipes is related to pressure, which is intentionally there. To maintain useful water pressure we would have to provide the energy elsewhere (higher water towers for example, which would require more energy to fill). It's a very common and understandable misconception that the energy in municipal water can be exploited.
Edit: I clearly misread your original comment, you weren't suggesting extracting energy from municipal water at all.
