Salmon Creek Basin near Tumwater could see groundwater flooding

Thurston County is advising residents of the Salmon Creek Basin south of Tumwater to expect areas of groundwater flooding similar to 2006.

Current groundwater levels are higher than usual for this time of the season, county staff says, so additional precipitation may result in flooding. Areas around 93rd Avenue Southwest, 88th Ave Southwest and other low-lying areas in the basin are already experiencing minor flooding.

However, the county does not expect flooding will be as prolonged or widespread as it was in 1999, when the water levels were much higher than in 2006.

Groundwater flooding is not the same as flooding from rainstorms or swollen rivers. Groundwater flooding comes up to the surface from below ground.

County staff is collecting data within the basin and will continue to monitor groundwater conditions. Check Thurston County’s Emergency Operations Center for helpful tips: www.co.thurston.wa.us/em/index.htm and monitor Water Resources website for up-to-date groundwater data from Salmon Creek Basin: www.co.thurston.wa.us/monitoring-salmoncreek/.

The county warns property owners that sandbags are not effective in controlling groundwater flooding. Residents should plan for restricted access to their property or driveways, and prepare for utility or septic outages.

Meanwhile, high tides in Budd Inlet could result in water on downtown Olympia streets between 5 and 8 a.m. Thursday, Olympia officials are warning.

Areas affected by the flooding could include:

▪ Fourth, Fifth and State avenues between Columbia Street and the Fourth Avenue bridge.

▪ Columbia Street between B and Corky avenues.

▪ Thurston Avenue between Jefferson and Franklin streets.

Portions of the above roads could be closed. Residents can report flooding to Public Works Dispatch at 360-753-8333.

This story was originally published March 9, 2016 at 3:56 PM with the headline "Salmon Creek Basin near Tumwater could see groundwater flooding."