Unusually dry weather this year meant that since July, the Portland Water Bureau has been supplementing the Bull Run water supply with a blend of groundwater from our Columbia South Shore Well Fields. Fall rain has finally returned, and as of November 4, 2015, Portland will return to 100 percent Bull Run water. As we return to the Bull Run source, especially at this time of year, some customers may notice a slight color change in their drinking water.
This is a normal occurrence in our system, as our water supply originates in the Bull Run Watershed near Mt. Hood. Before the water is treated and enters the distribution system, it can take on a tint from organic materials that are washed into the streams and the reservoirs in the watershed, particularly after the first fall rains. Drinking water from the Bull Run is not filtered, which is often why the color can be seen in tap water or staining the filters in your business or home.
The color you see is produced by tannins in organic material, much the same as the color you find in a cup of tea. There is nothing harmful to your health from these tannins. The color effects only the appearance of the water, not the quality.
The length of the fall color season varies with the strength and duration of the rains we experience during this time of year and how much organic material is carried into the system.
As always, the Portland Water Bureau constantly monitors the water entering the distribution system to ensure that it continues to meet all state and federal regulations for safe drinking water, and customers are notified of any changes that may affect the quality of the water we bring to you.
Any questions may be directed to the Water Quality Information Line at 503-823-7525.
General Information: 503-823-4000
1221 SW 4th Avenue, Room 110, Portland, OR 97204