Reservoir at Mount Tabor
These reservoirs, according to Portland's NBC affiliate KGW, are not filtered. This came to light June 30, 2008 when KGW reported two people were caught skinny dipping in one of the offline reservoirs the night of June 29. Reservoir officials say it's fortunate this particular reservoir was offline at the time, because draining and refilling it would have cost tens of thousands of dollars. Creating covers for the reservoirs has been proposed in the past but would cost the city about $500 million. The uncovered reservoirs were again in the news in early December 2009 when an E. coli outbreak warning was issued for Portland tap water. Residents were urged to boil the water they use for drinking and washing dishes.
On June 15, 2011, a man was observed urinating in a nearly 8,000,000 gallon reservoir, prompting city officials to drain the water at a cost of around $36,000.