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Contact Report Details

PWS ID: OR41 00665
PWS Name: TUALATIN VALLEY WATER DISTRICT
 
Who Was Contacted: Tara Vanderwey
Contact Phone: (Email address hidden)
Contact Date: 10/28/2025
Contacted By: ALFAFARA, NICOLE (DWP)
Contact Method/Location: Email
 
Assistance Type: WATER QUALITY ALERT RESPONSE
Reasons: Coliform
 
Details: System reported a routine coliform sample collected on 10/28/2025 came back positive for total coliform (absent E. coli). The sample site is located in the 650 pressure zone, near NW Laidlaw Road and NW Saltzman Road. Chlorine residual at this site was 0.75 ppm. Three repeats were collected but no triggered source sample from the Grabhorn well is required since it was not running at the time. Results of repeat samples are expected on 10/29/2025.

10/29/2025 Update: Repeat samples came back TC-/EC-. No further action needed.
 
Associated Alerts: TCR-4796 - 10/28/2025 - COLIFORM (TCR)



More information for this water system: SDWIS ID 4065
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