OHA Drinking Water Services
OR41
PWS ID: 00665 ---- TUALATIN VALLEY WATER DISTRICT
System Type: C    Population: 224,600


Current Open Coliform Sample Schedule
(subject to change based upon future test results)
DIST-A:  150 Routine sample(s)  per Month to be taken beginning 11/01/2017 -
GWR:  SRC-CA:  1 Assessment sample(s)  per Year to be taken beginning 01/01/2012 -

(A begin date of 01/01/1991 indicates the year the Total Coliform Rule was established)

Public water systems that use chlorine or chloramines must measure the residual disinfectant level at the same points in the distribution system and at the same time when total coliforms are sampled.

Repeat, Temporary Routine, and Prior Coliform Sample Schedules
(Schedules in bold reflect current schedules)

GWR:  1 Triggered sample(s) to be taken and reported  06/24/2024 - 07/05/2024
       1 at SRC-CA - WELL 1 - GRABHORN ASR
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TCR:  3 Repeat sample(s) within 24 hours of a TC+ Routine Sample to be reported   06/25/2024 - 07/05/2024  at DIST-A  
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GWR:  1 Triggered sample(s) to be taken and reported  02/12/2024 - 02/23/2024
       1 at SRC-CA - WELL 1 - GRABHORN ASR
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TCR:  3 Repeat sample(s) within 24 hours of a TC+ Routine Sample to be reported   02/13/2024 - 02/23/2024  at DIST-A  
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GWR:  1 Triggered sample(s) to be taken and reported  07/17/2023 - 07/28/2023
       1 at SRC-CA - WELL 1 - GRABHORN ASR
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TCR:  3 Repeat sample(s) within 24 hours of a TC+ Routine Sample to be reported   07/18/2023 - 07/28/2023  at DIST-A  
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TCR:  3 Repeat sample(s) within 24 hours of a TC+ Routine Sample to be reported   09/20/2019 - 09/30/2019  at DIST-A  
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GWR:  1 Triggered sample(s) to be taken and reported  06/19/2019 - 06/30/2019
       1 at SRC-CA - WELL 1 - GRABHORN ASR
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TCR:  3 Repeat sample(s) within 24 hours of a TC+ Routine Sample to be reported   06/20/2019 - 06/30/2019  at DIST-A  
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GWR:  1 Triggered sample(s) to be taken and reported  06/12/2019 - 06/23/2019
       1 at SRC-CA - WELL 1 - GRABHORN ASR
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TCR:  3 Repeat sample(s) within 24 hours of a TC+ Routine Sample to be reported   06/13/2019 - 06/23/2019  at DIST-A  
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TCR:  3 Repeat sample(s) within 24 hours of a TC+ Routine Sample to be reported   07/11/2018 - 07/21/2018  at DIST-A  
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GWR:  1 Triggered sample(s) to be taken and reported  07/10/2018 - 07/21/2018
       1 at SRC-CA - WELL 1 - GRABHORN ASR
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GWR:  1 Triggered sample(s) to be taken and reported  07/03/2018 - 07/14/2018
       1 at SRC-CA - WELL 1 - GRABHORN ASR
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TCR:  3 Repeat sample(s) within 24 hours of a TC+ Routine Sample to be reported   07/04/2018 - 07/14/2018  at DIST-A  
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TCR:  120 Routine sample(s) per Month to be taken   01/01/1991 - 10/31/2017  at DIST-A  
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TCR:  3 Repeat sample(s) within 24 hours of a TC+ Routine Sample to be reported   06/07/2017 - 06/17/2017  at DIST-A  
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TCR:  3 Repeat sample(s) within 24 hours of a TC+ Routine Sample to be reported   09/08/2016 - 09/18/2016  at DIST-A  
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TCR:  3 Repeat sample(s) within 24 hours of a TC+ Routine Sample to be reported   03/26/2014 - 04/09/2014  at DIST-A  
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TCR:  3 Repeat sample(s) within 24 hours of a TC+ Routine Sample to be reported   05/16/2013 - 05/27/2013  at DIST-A  
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TCR:  3 Repeat sample(s) within 24 hours of a TC+ Routine Sample to be reported   12/18/2012 - 01/01/2013  at DIST-A  
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TCR:  3 Repeat sample(s) within 24 hours of a TC+ Routine Sample to be reported   11/29/2012 - 12/13/2012  at DIST-A  
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TCR:  3 Repeat sample(s) within 24 hours of a TC+ Routine Sample to be reported   10/25/2011 - 11/08/2011  at DIST-A  
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TCR:  3 Repeat sample(s) within 24 hours of a TC+ Routine Sample to be reported   10/12/2011 - 10/26/2011  at DIST-A  
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TCR:  3 Repeat sample(s) within 24 hours of a TC+ Routine Sample to be reported   09/14/2011 - 09/28/2011  at DIST-A  
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GWR:  1 Triggered sample(s) to be taken and reported  09/13/2011 - 09/28/2011  at SRC-CA  WELL 1 - GRABHORN ASR
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TCR:  3 Repeat sample(s) within 24 hours of a TC+ Routine Sample to be reported   02/08/2011 - 02/22/2011  at DIST-A  
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GWR:  1 Triggered sample(s) to be taken and reported  11/18/2010 - 12/03/2010  at SRC-CA  WELL 1 - GRABHORN ASR
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TCR:  3 Repeat sample(s) within 24 hours of a TC+ Routine Sample to be reported   11/19/2010 - 12/03/2010  at DIST-A  
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TCR:  3 Repeat sample(s) within 24 hours of a TC+ Routine Sample to be reported   07/20/2010 - 08/03/2010  at DIST-A  
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TCR:  3 Repeat sample(s) within 24 hours of a TC+ Routine Sample to be reported   09/23/2009 - 10/07/2009  at DIST-A  
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TCR:  3 Repeat sample(s) within 24 hours of a TC+ Routine Sample to be reported   08/14/2008 - 08/28/2008  at DIST-A  
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TCR:  3 Repeat sample(s) within 24 hours of a TC+ Routine Sample to be reported   12/18/2007 - 01/01/2008  at DIST-A  
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TCR:  3 Repeat sample(s) within 24 hours of a TC+ Routine Sample to be reported   10/17/2007 - 10/31/2007  at DIST-A  
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TCR:  3 Repeat sample(s) within 24 hours of a TC+ Routine Sample to be reported   10/04/2007 - 10/18/2007  at DIST-A  
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TCR:  3 Repeat sample(s) within 24 hours of a TC+ Routine Sample to be reported   03/22/2007 - 04/05/2007  at DIST-A  
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TCR:  3 Repeat sample(s) within 24 hours of a TC+ Routine Sample to be reported   03/22/2006 - 04/05/2006  at DIST-A  
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TCR:  3 Repeat sample(s) within 24 hours of a TC+ Routine Sample to be reported   08/09/2005 - 08/23/2005  at DIST-A  
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TCR:  3 Repeat sample(s) within 24 hours of a TC+ Routine Sample to be reported   08/10/2004 - 08/24/2004  at DIST-A  
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TCR:  3 Repeat sample(s) within 24 hours of a TC+ Routine Sample to be reported   04/06/2004 - 04/20/2004  at DIST-A  
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TCR:  3 Repeat sample(s) within 24 hours of a TC+ Routine Sample to be reported   05/21/2002 - 06/04/2002  at DIST-A  
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Hide schedules prior to 2021


Instructions and Notes
  1. If no prior sample schedules appear, then no prior schedules exist within the database.
  2. Schedules for Oregon very small systems might not appear. If the system is active, samples must be collected for the presence of coliform bacteria once per month or once per quarter depending on water type, seasonal operating cycle, or previous sampling results.
  3. If a sample tests positive for total coliform or E. coli, a minimum of 3 repeat samples must be collected. At water systems where quarterly monitoring takes place, 3 routine samples must be collected the month following one in which a routine sample tested positive for the presence of total coliform or E. coli.

    Any time a sample tests positive for the presence of coliform bacteria, the system's operator should contact their regulator. For this water system, that is:
    DRINKING WATER SERVICES
    Nicole Alfafara
    (503) 278-1531




More information for this water system: SDWIS ID 4065
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