What is the minimum design pressure regulation for a distribution system?

The minimum design pressure regulation for a water distribution system is established to ensure that water can be effectively delivered throughout the system, including to consumers at the furthest points of service. A minimum design pressure of 30 psi is required to maintain adequate flow rates and to provide sufficient pressure for firefighting and other emergency services. This level of pressure helps to prevent issues such as low flow, inadequate supply during peak usage, and potential contamination risks that can arise from backflow when pressure drops too low.

Lesser pressures, such as 20 or 25 psi, may not provide sufficient force to meet these operational needs, especially in residential and commercial areas where higher demands are placed on the system. These lower pressures could result in inadequate water service, increased likelihood of disruptions during peak usage, and difficulty in meeting safety standards for fire protection. Thus, a minimum design pressure of 30 psi is a regulatory guideline that aims to balance the effective distribution of water and maintain system integrity.