Site Type

Site Name


PRO - Prosser Diversion Dam Combined

Adult Fishways (all three) and Juvenile Bypass/Sampling Facility at Prosser Dam

Operated by:


First year:


Last year:




Site Contacts


Nicole Tancreto
(503) 595-3100


Don Warf
(509) 735-2773


Photo Gallery

Operational Dates

Year Start Date End Date Notes
2014 1/1/2014 1/1/2015 JMF was dewatered February 3-23.
2016 1/1/2016 1/1/2017 The JFF was in operation from January 10-July 9.
2015 1/1/2015 1/1/2016
2017 1/1/2017 1/1/2018
2004 11/16/2004 1/1/2005 First year of operation. Supercedes original PRJ site, expanded to include the PIT tag antenna array at the Left Bank adult ladder counting window, which was brought on-line on Nov. 16, 2004.
2005 1/1/2005 1/1/2006 The JFF started sampling fish at 9 AM on Jan. 23. The JFF was dewatered on July 6, and all fish were subsequently routed to the river via the Primary Bypass Flume. The right ladder was watered up on Aug. 19, 2005; the new PIT tag detectors in this ladder were first activated on Aug. 30. The new PIT tag detectors in the middle ladder were first activated on Oct. 26, 2005.
2006 1/1/2006 1/1/2007 The juvenile fish lab watered-up at 9:00 AM on January 8, 2006. The juvenile lab flooded on April 30 and was out of service until 9 AM on May 31. The Left Bank and Middle ladder detectors were taken out of service on May 19 due to high river flows, with leaks or the threat of flooding in the PIT tag equipment vaults. The Center Ladder detectors were returned to service at ~14:30(PST) on May 23. The Left Bank Ladder returned to service at ~8AM on May 25. The juvenile fish lab was dewatered on July 8 for the rest of the migration year. The Middle Ladder was dewatered on July 6, and rewatered between Nov. 6 - 13 in response to a flood event. The denil sampler in the Right Bank Ladder at Prosser was in operation from Sept. 25 - Nov. 8, Nov. 13 - Nov. 21, and Nov. 27 - Dec. 5, 2006. The denil bypasses the counting window in the Right Bank Ladder. Therefore, fish were effectively diverted around the Right Bank Ladder PIT tag antennas (05 and 06) during these intervals.
2007 1/1/2007 1/1/2008 The JFF was watered up on Jan. 9, 2007. Chandler Canal and the JFF were dewatered between Jan. 30 and March 22. The PIT tag detection equipment was pulled from the center and left ladders on March 13 due to high water and the potential for flooding. The equipment was re-installed on March 21, at which time we observed that all three ladders were dewatered. The three ladders watered up between March 22-30. The left ladder was dewatered on April 16 or 17, and was returned to operation sometime before April 26. The right ladder was dewatered between July 5-17. The JFF was dewatered on July 10.
2008 1/1/2008 1/1/2009 The Prosser juvenile fish sampling facility (JFF) watered-up on Jan. 6 and sampling operations began on Jan. 7. The canal (and JFF) was dewatered from Jan. 23 until Feb. 3 due to cold weather. The transceivers in the left and center adult fish ladders were removed between May 16 and May 22 due to high river flows and possible flooding of the equipment rooms. Sampling operations for the 2008 outmigration concluded on July 19, and the JFF was dewatered. The right bank ladder denil was in operation continuously from September 2 until December 11, during which time 76 PIT-tagged fish were detected in that ladder.
2009 1/1/2009 1/1/2010 The detection equipment was removed from the left and center ladders on January 7 due to the threat of flooding, and re-installed on January 14. The juvenile fish sampling facility (JFSF) watered up for the season on Jan. 23. The JSFS was dewatered from May 31 until June 5 due to a broken hinge pin on the track rack cleaners for the channel. The JSFS was dewatered for the season on July 25.
2010 1/1/2010 1/1/2011 The Chandler Canal JFF watered up at 8 AM on January 3. The JFF dewatered at 10 PM on July 17.
2011 1/1/2011 1/1/2012 The Chandler Canal JMF watered up on Jan. 14. The JMF operated from Jan. 14-18, Jan. 21-24, and resumed operation on Jan. 27. All three ladder entrances were closed on Jan. 18; the right ladder reopened on Jan. 24, the middle ladder reopened on Jan. 26, and the left ladder returned to service the week of March 21. Due to adverse river conditions, the center and left bank ladder exit gates were closed from Apr. 1 to Apr. 6. The juvenile fish facility was dewatered from Apr. 1 to Apr. 5 for repairs. All three adult ladders were closed May 16-May 25. The JFF was shut down on July 30. Left ladder lost power for several hours on November 28.
2012 1/1/2012 1/1/2013 The JMF watered up sometime during the week of December 26, 2011, and the facililty began operations on January 3. All three ladders were closed February 23-27 due to flooding. Left and middle ladders closed on April 25 due to high water and debris.
2013 1/1/2013 1/1/2014
2018 1/1/2018 1/1/2019
2019 1/1/2019 1/1/2020 Site operated year round, but unknown when JFF was in operation.

Current and Historic Site Configurations

Config Seq: 110

Start Date: 8/30/2005

End Date:

Config Seq: 100

Start Date: 10/19/2004

End Date: 8/30/2005

Event Logs