http://www.tag.washington.edu/papers/papers/PortlandClimateReportFinal.pdf
Precipitation and temperature change, due to global warming, has put our water supply in jeopardy. Along with climate change, increased future population and demand will strain the Pacific NW freshwater supply. Portland’s water comes from the Bull Run watershed. Bull Run is experiencing less late-spring and summer flows; on average, the flow from April to September has decreased 20,000 CFS-days (12.9 billion gallons). With an increased population demand, the watershed will require approximately 2.8 billion gallons more storage per year. ”The increase in demand associated with anticipated regional growth during the summer reservoir drawndown, with considering climate change, averages 4.1 billion gallons by the year 2020 and 5.5 billion gallons by 2040.” The most extensive shift will occur by 2040 and will result in a 12 billion gallon increase demand staining the water supply even further. The average minimum storage will decrease by 4.1 gallons by 2020 and 5.5 by 2050.
