(Portland, OR) -- The City of Portland is back to using water from the Bull Run reservoir. In early November, heavy rain storms caused the reservoir to get cloudy with organic material from heavy runoff. Seven-billion gallons of water flowed into the reservoir in a 24-hour period. The Water Bureau switched sources to the Columbia South Shore Well Field. Now that the turbidity in the reservoir is gone, the water is being switched back. It could take two weeks for Bull Run water to flow through the entire system. You might notice tea colored water, which is due to the reservoirs refilling. The discoloration is harmless and will eventually go away.