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Measuring steam flow  Photo of a staff marker  Hyrologist taking measurements  Photo of a wier  Hydrologist maintaining equipment on the 520 bridge  Photo of a staff marker

The Hydrologic Information Center provides public access to rainfall, streamflow and other hydrologic data collected at King County gage sites. Data currently available from this web site include:

  1. daily rainfall totals
  2. average daily stream discharge rates
  3. 15-Minute rainfall and streamflow
  4. discrete water quality data

About the Hydrologic Monitoring Program gives a detailed description of gaging sites, gaging equipment and monitoring procedures.

To Obtain Data:

Please go to the Hydrologic Data Download Page.

Sea-Tac Precipitation Summary

Are we having a wet/dry/average year of precipation as recorded at Sea-Tac International Airport?  The Sea-Tac precipitation page displays the current daily total precipitation as recorded at Sea-Tac by the National Weather Service. 

Hydrology Presentations

View presentations given by King County hydrology staff on the Science Seminar Web site.

If you have question on this site, please contact Brendan Grant 206-477-4698