The Portland Water Bureau has returned to supplying customers with 100% Bull Run water following routine maintenance of the Columbia South Shore Well Field.

The well field, which includes wells, pumps, treatment systems and electronic controls, serves as a supplemental water source during summer months and can replace Bull Run water during emergencies. The bureau said routine maintenance allows crews to identify and address issues and ensure the groundwater system is ready when needed.

The transition back to Bull Run water occurred Aug. 21, although it may take up to two weeks for customers throughout the system to receive 100% Bull Run water at their taps, depending on their location.

The bureau said it notifies media outlets and sensitive water users when groundwater is activated or significant operational changes occur.