Who could resist a trip to "the source?" I've always been fascinated by the underground network of pipes and pumps that supply our freshwater and remove our waste water. Turning the tap, I wonder where does this water come from, how did it get here, how pure is it and how was it purified? So when offered the opportunity to tour the Bull Run Watershed – source of drinking water for 20 percent of all Oregonians – I was happy to accept.
The Portland Water Bureau's tours of the watershed provide a tremendous insight into the history, geography and challenges of providing clean water to a growing community. The tour takes a full day (bring your own lunch), and is the only way those of us who don't work there can legally enter the watershed. Access has been restricted since 1904 to protect the water quality.
Our first stop was the source of the Bull Run River, a gentle stream about 4,700 feet up on Mount Hood. The Bull Run Watershed gets about three times more rainfall annually than the valley below, and that rain is the primary source of the water we drink. Snow melt from Mount Hood is separated from the watershed by a ridge, so it only provides a small fraction of the water in the system.
From the source, we traveled to the system's first reservoir, completed in 1929. The reservoir holds 10 billion gallons of water. Another smaller reservoir below it holds an additional 8 billion gallons. Together, 18 billion gallons may seem like a huge amount of water, but because it is a rain-fed system, and rainfall there drops off in summer, the reservoirs are drawn down every year to supply water for the homes and businesses in and around Portland. In low rainfall years, the reservoirs can take well into the winter months to refill.
So what is the most important lesson to be learned on a tour of our watershed? Cherish that water coming out of your tap. Don't waste it. The Bull Run used to deliver about 4 billion gallons of water a year to its customers. Today, that demand is 40 billion gallons a year. The reservoirs can store 18 billion gallons. Do the math.
Since 1993, Metro has been working with all of the region's water providers to plan for future water use. The Regional Water Providers Consortium, on which I served as a Milwaukie city councilor as well as a Metro Councilor, collaborates to offer water conservation planning and information. All of the water used in our region comes from sources that are limited by quantity, quality or storage capability. It's critical that we all understand these constraints and use water efficiently.