GroundRules
12VAC5-590-1120: Minimum pipe size
Where this section sits in the code
- Title 12. Health
- Agency 5. Department of Health
- Chapter 590. Waterworks Regulations
- Part III. Manual of Practice for Waterworks Design
- Article 6. Water Distribution Systems [Repealed]
A. The minimum size pipe for water distribution mains shall be four inches in diameter. Pipes of lesser diameter may be used in the following instances:
1. When the run is less than 300 feet, two-inch diameter pipe may be used.
2. When the run is less than 600 feet but more than 300 feet, three-inch diameter pipe may be used.
3. Any departure in sizing shall be justified by hydraulic analysis and future water demands.
B. Fire hydrants shall not be connected to water mains that are not designed to carry fire flows. Connection of a fire hydrant to a pipe of less than six inches in diameter is prohibited.
C. Where a noncommunity waterworks serves a single building, the plumbing shall be in accordance with the USBC. Where a noncommunity waterworks serves two or more buildings, the pipe shall be of sufficient size to provide adequate flow and pressure in order to meet the system demands.
Collected 2026-09-14T04:50:43Z. Source file · JSON