Monday, November 16, 2015

Fire and floods

Early warning needed in areas scarred by wildfire

By Joye Redfield-Wilder – Communications Manager, Central Region

Across the state, fires have left a scarred landscape where more than a million acres of timberland and sage burned this summer. North Central Washington experienced a one-two punch, suffering the state’s two largest groups of wildfires back-to-back in 2014 and 2015.

Together, the Carlton Complex Fire of 2014 and the Okanogan Complex Fire of 2015 burned more than a half-million acres of land in mountainous Okanogan County.

Fires also raged this summer along Lake Chelan from Stehekin to the lake’s namesake resort town 50 miles to the south. They burned around Mount Adams, north of Spokane, along the Columbia River and in the Blue Mountains. Wildfire even scorched the Olympic National Rain Forest.

Lost were homes, livestock and three lives. Gone too, is the protective vegetation that helps prevent flash flooding.

Contractors clean up after dam breach in 2014

Flash flooding a wakeup call

A month after the Carlton Complex Fire, torrential rains and flash flooding breached several earthen dams, wiped out county roads and heaped more devastation on residents who were caught off guard.

In an effort to help everyone to be better prepared, Ecology was able to deploy a total of 17 flash flood warning rain gauges last fall in burned out areas west of Wenatchee and in the Methow and Okanogan river valleys.

Gauging stations collect data in areas where the National Weather Service/NOAA has no radar reception. Powered by solar panels and two car batteries, the information is sent by satellite to the weather service in Spokane. Residents receive early flood warnings via local broadcast media, and emergency management social media and text messaging.

Entiat trailhead  rain gauge

Rain gauge response, 2015

Fast-forward to this autumn. Residents around Lake Chelan in Chelan County and in the area of the Okanogan Complex fires now face the same flooding hazards as their neighbors did in 2014. Field staff with Ecology’s Environmental Assessment Program have deployed nine more rain gauges in rugged areas that have no weather radar coverage.

In addition, two stream flow gauges have been placed in the upper and lower Entiat River watershed to provide crucial information on how fast water is rising during a significant rain event, and to further help NOAA know if local agencies should be sent a flash flood warning.

“Rain gauges provide real time information on the ground, in areas with poor radar coverage, and help determine whether flash flooding is imminent and whether flash flood warnings should be issued,” said NOAA hydrologist Katherine Rowden. “The stream gauges in the Entiat will show rises well upstream of residents to help us get effective early warnings out to those downstream.”

State and federal experts and local emergency responders helped to identify areas where the burn intensity, terrain, and conditions downhill or downstream posed the greatest threats.

Efforts to address such post-wildfire hazards aren’t always funded as part of the immediate response and recovery efforts. Ecology stepped up to the plate to provide the much-needed service, using creative resources and a well-trained field staff.

Ecology Rain Gauge You Tube:

Learn more about how these rain gauges work on our You Tube video, Rain Gages for the Carlton Complex Fires.

You can also visit each station virtually and see real-time river flow data at our Flow Monitoring Network webpage.

Flash flood gauges in North Central Washington 

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