Minimum residual pressure of 25 psi or no less than 20 psi during instantaneous demand such as fire flow. Maximum pressure is only limited by how much the pipe and/or materials are rated. There is no high pressure limit by regulations.
Plumbing code requires pressure regulators to be installed on services where pressures from the water distribution system are above 80 psi.
There are numerous factors that affect pressures throughout the Commission’s water distribution system, such as: elevation, pump runs, system demands, proximity to elevated storage, etc. Water pressures on the Commission’s distribution system may vary from 25 psi to 170 psi. Due to these possible high pressures, our system is designed and built to withstand pressures of 200 psi.
Due to the possibility/presence of high pressures in water systems throughout the nation, the International Plumbing Code Section 604.8 requires “where water pressure within a building exceeds 80 psi static, an approved water –pressure reducing valve conforming to ASSE 1003 with strainer shall be installed to reduce the pressure in the building water distribution piping to 80 psi static or less.”
The Commission recommends that you have the pressure tested at your home or business and make the necessary improvements to ensure the internal pressure does not exceed 80 psi. The Commission does not and will not take any responsibility for any damage that may result from high interior water pressures.