Operation Canvasback: Canvasbacks and Diesel Fuel Don’t Mix
The fall migration of canvasbacks was underway on the Upper Mississippi River National Wildlife and Fish Refuge on November 25, 2013, when the towboat Stephen L. Colby struck a submerged object and began spilling diesel fuel into the Mississippi River at Le Claire, Iowa. The towboat was carrying 90,000 gallons of diesel fuel and 2,000 gallons of lube when it began to sink.
Fifty thousand waterfowl, mostly canvasbacks, were staging for migration just 26 miles north of the fuel spill and 2,000 canvasbacks had moved to within one mile of the spill. It was critical that a massive effort, dubbed Operation Canvasback, be launched immediately to avert a catastrophic disaster that could impact tens of thousands of waterfowl.
Hundreds of bald eagles were also present as they vigilantly followed the migrating waterfowl. And to complicate response actions further, hundreds of local non-migratory Canada geese and mallards frequented the spill area. If any ducks or geese were to get oiled and couldn’t fly, eagles would take advantage of the bounty feast and also be impacted.
The crippled towboat had lost power in the navigation channel due to water pouring into its hull. Miraculously, another towboat was close by and pushed the floundering Colby to shore at Le Claire’s waterfront. This location was only a few blocks from the Fire Department that deployed booms around the sunken vessel within 50 minutes of the incident, greatly reducing the volume of diesel fuel spilling downriver. Fortunately, the spill did not occur upriver, where an intricate system of backwaters is present within the Upper Mississippi River National Wildlife and Fish Refuge.
An Incident Command Team led by the U.S. Coast Guard was immediately mobilized. Rock Island Ecological Services contaminants biologist Mike Coffey was the Team’s Wildlife Branch Leader. Coffey immediately requested assistance from additional staff at the Ecological Services office, Upper Mississippi River National Wildlife and Fish Refuge, and Port Louisa National Wildlife Refuge. The Iowa Department of Natural Resources and U.S. Coast Guard also provided personnel for the Wildlife Branch.
A dramatic response effort was conducted during the next 10 days with over 100 personnel on site daily during the critical response period. The primary tasks were to monitor the movements of migrating and local ducks and geese into the area and be prepared to haze them away to prevent exposure to the diesel fuel while the responders removed the oil from the river and salvaged the 600-ton vessel.
Strong river currents, howling winds, and freezing river conditions challenged the response activities. The spilled fuel turned the Mississippi River surface waters red and a diesel stench saturated the air. The Wildlife Branch conducted daily boat patrols and made plans to capture and rehabilitate oiled wildlife, if necessary. Volunteers with Living Lands and Waters placed colorful streamers along the shoreline to deter wildlife use and assisted with boat patrols. Extensive shoreline searches were conducted in boats, vehicles, and on foot looking for oiled wildlife.
The hard work of the Incident Command Team and Wildlife Branch was rewarded as the migrating canvasbacks took to the sky and avoided the spill area. Two mallards were recovered from within the spill area and both had injuries related to hunting. One Canada goose was found dead by a hunter who reported that it was covered in oil. No fish or mussel mortality was identified. Additional mussel surveys may be conducted in spring.
The towboat sinking occurred in an area known as the Rock Island Rapids where rock formations are prevalent and dynamite had to be used to clear the original 9-foot channel. The NTSB investigation determined that the towboat struck a rock resulting in multiple holes on the underside hull. The exact amount of diesel fuel that spilled into the river will never be determined. Incredibly, the spill site and adjacent areas were minimally impacted, as best can be determined, due to the quick response actions of the Incident Command Team and the dilution of fuel by the strong river currents along this relative narrow channel area. Operation Canvasback was deemed a grand success and provided closure to one of the largest fuel spills ever experienced on the Upper Mississippi River.
By Ed Britton, Project Leader,
Upper Mississippi River NW&FR – Savanna District