By Kim Smiley

On September 9, 2013, a reported 1,400 tons of molasses was inadvertently spilled into Honolulu Harbor in Hawaii, devastating the sea life.   When I think of ocean spills, pictures of oil-covered animals jump into my mind, but the molasses spill is proving to be potentially just as damaging to the environment.

This incident can be analyzed by building a Cause Map, an intuitive format for performing a root cause analysis.  A Cause Map visually lays out the causes that contribute to an accident to show the cause-and-effect relationships between them so that it’s easier to understand the factors that led to the issue.  Understanding all the causes and not just focusing on a single “root cause” helps broaden the potential solutions that are considered and can lead to a better long term solution. The first step in the Cause Mapping process is to define how the problem impacted the goals and then these impacts are used as the starting point for the Cause Map.

The most obvious impact from the molasses spill is that thousands of fish and other marine life were killed.  They suffocated because the molasses sank and displaced the oxygen- containing seawater in the harbor.  The density of molasses is what makes this spill so different from an oil spill.  Oil is lighter than water and floats on top of the ocean while molasses sinks to the bottom, with devastating effects at all levels in the ocean.  Divers investigating the molasses spill reported that there were no signs of life in the ocean near the spill; all bottom dwellers had been killed.

The fact that molasses sinks also means that there is no practical way to clean it up.  One positive about molasses is that molasses, unlike oil, will mix with water. It sits on the bottom until it is diluted and ocean movements disperse it.  Since the spill occurred in a protected harbor, the ocean movements are weaker and the time frame to move the molasses is longer than it would be in the open ocean, but nature will eventually return oxygen levels in the harbor to life-supporting levels.

The cause of the spill has been reported to be a leaking pipe.  Molasses produced on Hawaii was being pumped into a ship for transportation to the mainland where it was planned for use in animal feed.  During the transfer, the molasses was accidently pumped through a pipe with a leak and nobody noticed before the majority of the molasses had been released into the harbor.  Details about what specifically caused the leak haven’t been released.

There are also other impacts from the spill that are worth considering.  With any environment issue, the cost of the investigation and any clean up that needs to be done is always substantial. Many businesses in the area were also impacted by a drop in tourism because the harbor was closed for about two weeks after the accident and normal tourism levels will probably not return until marine life in the area begins to recover.  There was also a potential safety risk to any swimmers for a time after the accident because the presence of thousands of dead fish could attract predators.

To view an Outline and high level Cause Map of this accident, click on “Download PDF” above.