The news cycle has been highlighting the possibility that an outbreak of Legionnaires’ Disease that occurred in and around the Flint, Michigan area last year may be connected to the toxic water problem Flint has been experiencing. This is due to a report from the same professor that helped to expose the lead in the water issue.
Possible Links Between Flint River Water (Without Corrosion Control) and Higher Legionella Occurrence
The professor raises the possibility that a lack of a corrosion control program may have created conditions favorable to the growth and transmission of the Legionella bacteria. The Governors’ office has pointed out that no link exists to connect the two.
I have another possible rationale that you won’t hear anywhere else. Legionella bacteria are prevalent in fresh water sources. They grow well in cooling towers and hot water systems which is large building complexes tend to be where outbreaks occur. They can also grow in areas such as the biofilm that lines the inside of water transmission mains which is why the professor suggested the link. They also can grow in pipes with limescale buildup. Care to guess where that may exist? The Flint Water Treatment Plant (WTP), that’s where.
The Flint WTP utilized a softening process during the time they utilized the Flint River as a water source. Lime was the chemical used to soften the water. The lime began as a powder called quicklime. It is mixed with water in a machine called a lime slaker which produces a slurry that is piped into a clarifier where it was mixed with the city water supply.
Legionella wouldn’t grow in the lime slaker itself while in operation as the water is too hot, around 210 degrees. Anything over 131 degrees will kill the bacteria. However, when the machine is offline (Flint has 4 with 2 in use during normal operation), the lime quickly hardens into a scale. The same goes for the hoses used to transport the slurry. Just as the bacteria may grow in the biofilm of the distribution water mains, it may grow in the limescale of the water plant machines and hoses.
You can ready this study here to see that the biofilm can protect the bacteria from excessive heat and that dead ends are prime breeding ground. Dead ends are areas of the distribution system where water just sits and doesn’t ‘turn over’. The chlorine residual is low here making the problem worse. Flint has lots of them due to the ever shrinking population and abandoned houses.
It’s likely we’ll never know if this was the missing link. Flint isn’t using the machines now that they’ve switched back to Detroit water as a a source. They won’t be needed later this year either when Flint switches to its new source, the Karegnondi pipeline bringing water directly from Lake Huron. So those conditions won’t be replicated again and you can be sure no one from the Governors’ office will ever pursue it as they have no desire to have additional liability heaped upon them.
Editors note: this author has reached out to several different organizations from local reporters to activists such as Erin Brockovich to give them a chance to get the inside story from someone who has intimate knowledge of the Flint water treatment operation. To date, none have taken advantage. We’ll continue to shine the spotlight on the truth regardless.