It’s not really a matter of force so much as pressure. The pressure of the water in most water-jet cutting machines is in the 40,000 psi to 100,000 psi range (280 MPa to 690 MPa).
The most effective types introduce small amounts of abrasive materials into the water stream to enhance their cutting ability.
Most water-jet cutters can cut through some amount of concrete - but the lower pressure kinds may not cut through large thicknesses.
At these pressures, you need a ruby or a diamond nozzle so that the nozzle itself doesn’t get eroded by the pressure. Some systems use exotic ceramics for the nozzle.