Buehner: Green River flooding in Auburn won’t recede until this weekend

Auburn residents dealing with Green River flooding face several more days of high water, according to KIRO Newsradio meteorologist Ted Buehner, who analyzed the latest river forecasts Monday.

Buehner, a retired National Weather Service forecaster who now provides weather analysis for KIRO Newsradio, reviewed the hydrograph for the Green River at Auburn and delivered a blunt assessment.

“Bottom line: it is not going to recede until at least this weekend,” Buehner said. “The water is coming from the rainfall runoff downstream from Howard Hanson and releases from the hydro project since it is close to filling up. Not good news for those low lying areas including SR 167.”

The forecast shows the Green River remaining at or near moderate flood stage through at least December 21, with flows hovering around 10,900 cubic feet per second before finally dropping later in the week.

Level 3 evacuation orders remain in effect

Emergency officials in Auburn issued a Level 3 “Go Now” evacuation order late Saturday night for the northern part of the city. The order covers the area between South 277th Street, 42nd Street Northeast, State Route 167, and the Green River.

Affected neighborhoods include the Trail Run community, Copper Gate Apartments, and surrounding areas. As the river seeped into those neighborhoods, it rendered multiple roads impassable.

The city has established two shelters for displaced residents:

• Auburn Community and Event Center on 9th Street Southeast
• Ray of Hope Day Resource Center on Auburn Way South

Extensive road closures affecting Auburn commuters

The city of Auburn posted an extensive list of road closures Monday, warning residents that many northbound routes out of the city are impassable. Drivers should expect significant delays and plan alternate routes.

Major closures include:

• Northbound Auburn Way N. from 37th Street N.W. to S. 277th Street
• West Valley Highway northbound from 37th Street N.W. to S. 277th Street
• S. 277th Street between Auburn Way N. and 108th Avenue S.E. in Kent
• SR 167 in the affected area
• B Street N.W. from 37th Street N.W. to S. 277th Street

The Trail Run neighborhood is accessible only through the private gate off 52nd Street N.E.

In southeast Auburn, Green River Road S.E. is closed from 100th Avenue Southeast to the city limits, and 104th Avenue S.E. is closed between Green River Road S.E. and S.E. 320th Street.

Landslide closes West Valley Highway

Separate from the flooding, a landslide has closed West Valley Highway between 15th Street N.W. and W. Main Street. The closure, caused by landslides and downed trees, will remain in place “for some time” while crews evaluate the damage, according to the city.

Why the flooding persists

The prolonged flooding stems from two factors. Heavy rainfall from last week’s atmospheric river continues to flow downstream from areas below Howard Hanson Dam. At the same time, the dam itself is nearing capacity, forcing the Army Corps of Engineers to release water to prevent the reservoir from overtopping.

Howard Hanson Dam, located upstream on the Green River, typically holds back floodwaters to protect downstream communities. But after absorbing record rainfall from last week’s storm and additional precipitation from the current atmospheric river, the reservoir has little remaining capacity.

Residents in flood-prone areas should monitor conditions closely and follow evacuation orders. Road conditions may change rapidly, and drivers should never attempt to cross flooded roadways.

What is a hydrograph?

A hydrograph is a chart that shows how a river’s water level or flow rate changes over time. Forecasters use hydrographs to track flooding events and predict when rivers will crest and recede.

The hydrograph for the Green River at Auburn shows two key pieces of information: observed water levels (what has already happened) and forecast levels (what meteorologists expect over the coming days). Horizontal lines mark the thresholds for action stage, minor flooding, moderate flooding, and major flooding.

In the current forecast, the Green River is expected to remain at moderate flood stage through much of the week, with flows staying above 10,000 cubic feet per second before finally dropping below minor flood stage around Dec. 21.

Charlie Harger is the host of “Seattle’s Morning News” on KIRO Newsradio. You can read more of his stories and commentaries here. Follow Charlie on X and email him here. 

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