GENERAL INFORMATION: 503-823-7404
1120 SW Fifth Ave, Suite 600, Portland, OR 97204
Starting Tuesday, July 30, 2013, the Portland Water Bureau will begin blending a small portion of water from its Columbia South Shore Well Field into the distribution system as part of a maintenance operation.
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.
The rate of groundwater pumping will vary throughout each day. Groundwater will be pumped at a rate of approximately 18 million gallons per day during work hours. No pumping will occur at night. The rate of groundwater production may decrease toward the end of the operation, scheduled for Friday, August 9, 2013. This maintenance may be extended as necessary.
The average contribution of groundwater to the system will be approximately three percent or less of the total daily water demand. The Portland Water Bureau will be blending this groundwater with water from the city’s Bull Run reservoirs. Due to the small amount being added, the bureau does not expect there to be a large change in water quality. It takes approximately 24 to 60 hours – depending on location and overall water demand – for the blended water to make its way through the distribution system to homes and businesses. The water quality of Groundwater, Bull Run and the highest expected blend can be found here.