Tomorrow, Aug. 10, the Portland Water Bureau will return to 100 percent Bull Run water. On July 25, the Portland Water Bureau blended a small portion of water from wells at the Columbia South Shore Wellfield to perform its annual maintenance operation of the groundwater system. Now that this maintenance operation is complete, the groundwater system is ready for use if needed for seasonal or emergency use.
Public notification is not required but the Portland Water Bureau informs the media and sensitive water users, as a practice, when it activates groundwater and when it has significant operational changes. The media and sensitive water users are again notified when the Portland Water Bureau returns to 100 percent Bull Run water.
As a result of careful planning, Portland is fortunate to have access to two excellent water sources that allow us to be prepared to meet the range of supply and demand conditions that occur in the Portland water system.
The Columbia South Shore Well Field is a high-quality water supply that meets or surpasses all federal and state drinking water regulations.
The city’s groundwater supply is a complex system composed of electric pumps, chemical feed systems, electronic controls and other equipment that must be operated regularly to identify maintenance needs. By doing this operation routinely, the bureau will ensure the reliability of the system when needed, either in an emergency or to meet seasonal supply demands.
During the groundwater maintenance run, the average contribution of groundwater to the system has been approximately 15 percent of the total daily water demand. Due to the low percentage of groundwater being blended with the Bull Run Source, the bureau does not expect there to be a large change in water chemistry. It takes up to two weeks, depending on location and overall water demand, for the 100 percent Bull Run water to make its way through the distribution system to homes and businesses.
Customers with questions are encouraged to call the Water Line at 503-823-7525.