Taste and odor issues have been nearly a yearly occurrence in the City’s drinking water for the last 60 years. The offending compound is called 2-methylisoborneol or MIB for short. The MIB is not harmful but is aesthetically unpleasant. It is produced inside blue green algae and then released into the water in the reservoir. Because of the nutrient contamination, especially phosphorus, in our reservoirs, the algae blooms rise to an incredible level in the summer and fall, releasing the MIB in large quantities into the water.
For the past four years, the Alliance Water Treatment Department has been able to keep MIB to undetectable levels. Each year the peak MIB concentration has increased over the past year. We are adding the maximum amount of powder activated carbon (PAC) possible with our current feed equipment to remove the MIB. The cost of the PAC is extremely high and has greatly increased the cost of water production.
We are working in the watershed to eliminate the anthropogenic (human produced) nutrient contamination sources that have plagued the reservoirs for over 60 years. We are also beginning the construction of new cutting edge technology called Ultra Violet Advanced Oxidation which will help us to reduce the taste and odor even at the high levels that are occurring in the reservoir. It will reduce the MIB to an undetectable level. This project will not be completed until late 2013/early 2014.