Is emergency power required for a water treatment plant?
Yes in most cases. The requirement is specified in the Arizona Department of Environmental Quality's (ADEQ) Engineering Bulletin No. 10, "Guidelines for the Construction of Water Systems" in Chapter 4, Section A.4.

The only exception would be for:
- A plant that is 100% redundant to another potable water source (e.g. a surface water treatment plant or a groundwater well field) that is capable of meeting the peak day demand for the water distribution area being served and the plant and the redundant potable water source are on separate electrical grids or power supplies.
- A plant that is 100% redundant to another potable water source (e.g. a surface water treatment plant or a groundwater well field) that is capable of meeting the peak day demand for the water distribution area being served and the redundant potable water source has redundant feeds from two different electrical grids or an emergency power supply.
- A plant which serves a water distribution area that has sufficient system storage capacity to meet the peak day demand and it can be demonstrated that the plant can be restored to normal operation within 24 hours after the interruption of service.

Requests for an exception will be reviewed and approved by the MCESD on a case-by-case basis. For more information, please call 602-372-2861.

Show All Answers

1. Is emergency power required for a water treatment plant?
2. Is emergency power required for groundwater production facilities?
3. Is emergency power required for distribution system facilities?
4. What are the requirements for equipment and process redundancy for a water treatment plant?
5. What are the requirements related to the rated capacity of a water treatment plant?
6. What are some key issues when converting a groundwater production facility to a water treatment plant?
7. What are the design requirements for venting wet wells, clearwells, tanks and reservoirs?
8. What are the design requirements for wet well, clearwell, tank or reservoir overflows?
9. What are the design requirements for entry hatches on wet wells, clearwells, tanks and reservoirs?
10. Can pump seal water be discharged to a pump wet well?