See the Bull Run. (Run bull, run.)

All of the water that flows out of taps here in Portland comes from the
Bull Run watershed up on Mt. Hood, where a series of reservoirs capture
and store the runoff from melting snow. To protect water quality, the
watershed is ordinarily off-limits to the public, so few of us ever get
to see the source of our drinking water. But on Saturday, September 13th
the Portland Bureau of Water Works will be offering one of their rare
tours. It’s a great chance to see a protected, almost-pristine forest
close to Portland. The tour costs $15 and advance registration is
required. To register, call (503) 823-7407.
– posted by Niels