Hard to beat using 3 sections of plastic pipe cut length wise in 4 to make a 12 blade Banki.
A plastic Banki can easily handle several hundred watts.
If much grit in the water, the plastic will fail faster.
Nice thing about a Banki, if more power is needed make it longer.

Make sure the pipe feeding the turbine is large enough without loosing pressure just before the nozzle.
Remember the job of the nozzle is to convert potential energy to kinetic energy. The nozzle area must be much smaller than the dia of pipe feeding it.