In the wintertime, member agency rights allow the JWC to pull all the water it treats from the Tualatin River.
The winter water flows on the Tualatin River are normally quite high and there is plenty of water to meet the needs of fish, farmers and urban use, including the recharging of Aquifer Storage and Recovery (ASR) wells in Beaverton.
Torrential rains can cause the river to overflow its banks and collect large amounts of sediment that are harder to remove from the water. The Water Treatment Plant (WTP) Operators monitor the incoming and outgoing water quality vigilantly during these periods of high “turbidity.” They adjust treatment chemical dosages and check equipment frequently in order to ensure all outgoing treated water maintains the same high standards for safe drinking water that are met when the river is quiet.