Spills photo identifier

Spills Program

Wenatchee Spill

(Information on this site is considered to be accurate at the time of posting, but is subject to change as new information becomes available.)

Columbia River Mystery Sheen

Thursday, March 23, 4 p.m.

We have halted the sonar and underwater camera operations, but we’re maintaining an aggressive investigation to find the source of the spill.

We have collected additional samples from the river and also we’re also collecting samples from possible sources to look for a potential match.

Chelan PUD has provided us with historical maps of the area. The maps date to the 1930s and provide a detailed reference of the local infrastructure at that time. This includes items such as petroleum tanks and storm systems.

We continued to monitor our oil-containment boom from the shore and water today. Some of the oil continues to escape from the containment area due to high river flow.

We are replacing absorbent pads that have become saturated with oil in one 20-foot stretch of river where the product is concentrating.

When a responsible party is verified, we’ll release more information.

Wednesday, March 22, 2017, 11 a.m.

State laboratory tests revealed late yesterday that the substance creating an oil sheen in Columbia River at Wenatchee is biodiesel. Spill investigators can now narrow their search for its source with a goal to keep it from getting into the river.

Emergency response crews have been working since early Saturday morning to find the source of the mystery spill. They placed oil-containment boom in the river early Sunday morning to contain the oil sheen. Crews have been investigating the scene since Friday, March 17.

Video observed from Chelan PUD surveillance cameras, which are pointed at the river, recorded an oil sheen on the river as early as March 15, two days before it was initially reported by passersby.

By March 18, state, federal and local partners formed a Unified Command to respond, involving the Department of Ecology, the U.S. Environmental Protection Agency and Chelan Emergency Management, with supported several federal, state and local agencies. The Washington State Patrol, City of Wenatchee, and Chelan County Fire District 1 also provided on-scene resources to support the spill.

Up until the lab results came in, responders had been using underwater sonar and cameras to find the spill source.

When a responsible party is verified, more information will be released.

Tuesday, March 21, 2017, 2 p.m.

Our ongoing investigation to identify and block the source of the spill continues today. We have hired contractor Global Diving & Salvage, Inc. to deploy a side-scanning underwater sonar unit to map the underwater terrain. The next step will be to deploy an underwater camera to look for the source of the spill. We reviewed Chelan PUD Security surveillance video footage from numerous cameras they have pointed at the river. The footage appears to show that the sheen began passing through the area on March 15, two days before it was initially reported. River flows are up.

Monday, March 20, 2017, 3 p.m.

Water samples that we collected are at the lab today to determine the type of product that is in the river. We continue our ongoing, active investigation to find and stop the source of the pollution. We will be using a side-scanning, underwater sonar device as well as an underwater camera. An odor of diesel remains in the area and there is a light rainbow sheen inside the spill-containment boom.

There has been minimal to light staining of the absorbent materials that have been in the river for 24 hours. We will continue to post information here, so stay tuned to this site.

Sunday, March 19, 2017, 11:30 a.m.

Responders continue to address the sheen on the Columbia River in the Wenatchee area. Earlier this morning, Chelan County Emergency Management provided support to place boom on the river to contain the sheen.

Saturday, March 18, 2017, 6 p.m.

Work continued this afternoon on the Columbia River. The Washington Department of Fish and Wildlife began assisting with evaluation of impacts.

Later in the afternoon, an underwater camera was deployed in the Columbia at Wenatchee to find the source of the oil sheen. The response team will continue efforts to address the incident.

Saturday, March 18, 2017, 1 p.m.

Ecology’s Central Regional Office arrived to the scene at 4:45 a.m. to do shore-side assessment and to help determine the source Saturday morning.

Ecology and Chelan PUD both put boats on the water Saturday morning to begin on-water observations and to continue work identifying a source. Chelan PUD's boat has left the scene.

An oil sheen remained in the river, approximately 50 feet from the west shoreline, between Thurston and Chehalis Streets in Wentachee. The continuous sheen spreads to approximately 20 feet wide, and extends approximately 1 mile down river. Responders are reporting a diesel odor in the area.

There have been no observations of wildlife directly impacted by oil.

A Unified Command has been formed with representatives from Ecology, the U.S. Environmental Protection Agency, and Chelan Emergency Management, who are supported by a number of other federal, state, and local agencies. The Washington State Patrol, City of Wenatchee, and Chelan County Fire District 1 have also provided on-scene resources to support the spill.

Ecology has mobilized eight Response Team members to:

  • Investigate the source of the oil.
  • Attempt to contain and recover the leaking oil.
  • Protect sensitive environmental, cultural, and economic resources.
  • Assess shoreline impacts.
  • Determine if wildlife impacts have occurred.
  • Keep the public informed.

Ecology continues to inspect the shoreline to determine the source of the sheen.

Friday, March 17, 2017, 8 p.m.

Just prior to 8:00 p.m., Wenatchee Fire reported a large mystery sheen on the Columbia River, just south of the Wenatchee city center. A strong diesel odor was reported in the area as well.

The source of the sheen and the odor are unknown.


Date of Incident & Location:
March 17, 2017

Approximately 50 feet from the river's west shoreline, between Thurston and Chehalis Streets in Wentachee, WA

Biodiesel, unknown qty.


Responsible Party:


March 19, 2017, Dept. of Ecology:
Boom placed on Columbia River to contain mystery sheen


Sandy Howard