Water Temperatures and Compliance

Salmon require cold water. Spring water temperatures in the Trinity River are important for smolts, while summer and fall temperatures are particularly important for adults.

The North Coast Region Basin Plan established a temperatures objectives:

Time Period Location Criteria
July 1-Sept 14 Douglas City < 60º F
Sept. 15 – 30 Douglas City < 56º F
Oct. 1 – Dec. 31 N. Fork confluence < 56º F

Water temperatures in the Trinity and Lower Klamath River are monitored to understand how well the dam releases met expected water temperature criteria (the 2009 report and others are available in our online library).  Meeting these objectives generally requires flows of 450 cfs from Lewiston Dam from the end of the ROD restoration flow release through October 15th.  Possible affects of the volume of Trinity Lake and water transit time through Lewiston Lake are under investigation.

Further information on water temperature is found in our Temperature-related Science pages.