Steve Guthrie, IA/MO regional manager of PeopleService, Inc., addressed the Maryville City Council members during their January 8 meeting, updating them on the drinking water situation which began emitting foul tasting water on November 22.
Because the weather has been so warm this year, it created more algae blooms than normal – this has been proven by lab analysis – creating a foul taste and odor. The water samples are within compliancy with the Department of Natural Resources (DNR) and it is safe for consumption despite the taste and odor.
“The City of Maryville and PeopleService, Inc. are continuing to work toward a solution for improving the taste and odor aesthetic qualities of the water. Staff remains in constant communication with the Missouri Department of Natural Resources who concurs with our chemical methods of treatment. Unfortunately, the sheer volume of water impacted by the algae blooms will require more time to correct the problem. We apologize for the inconvenience to our customers and ask for continued patience,” City Manager Greg McDanel stated.
So far, staff has tried multiple things to fix the issue. They have switched which intake they use in an attempt to access water below the blooms, they have converted to using free chlorine instead of chloramine, they have increased the carbon and the chlorine dioxide to their maximum safety limits and they have increased the sodium permanganate up to the limit where they started seeing issues with turbidity, which occurs when the chemicals begin fighting and reacting to each other, in the plant membranes, which are tubes that are too small for bacteria to enter that filter the water.
Each adjustment can take up to four days before staff can monitor the changes and up to a week before any water quality improvement can be noticed in the residencies. The chemicals are at the maximum levels for human consumption safety or for the safety of the membranes.
People Services were required to exhaust all chemical treatment options before moving forward and has been working with DNR to find a solution. The chemicals have proven to be ineffective at treating the issue. This is the first time People Services has experienced this situation in the 11 years they have managed Maryville’s water supply.
The water in the lake has just now reached a cold enough temperature to kill the algae. However, the oils secreted from the death of the algae blooms must dissipate, a timeline that is unknown.
If the weather stays below freezing for several months, the problem will fix itself eventually. If the weather stays warm, the algae will continue to affect the water.
Chemical treatment of the entire lake is not an option due to the size of Mozingo. City staff recommended that council purchase mechanical mixing technology such as a SolarBee for future treatment. A SolarBee would bring water from the bottom of Mozingo Lake to the surface, stirring the water and creating a constant flow, preventing algae growth at the intake cove.
Technology of that magnitude ranges between $120,000 and $300,000 and would be a line item that was not included in the budget.
Another third option that was proposed was to replace the water membranes in upcoming years along with the construction of granulated active carbon or GACs, which would allow the facility to use stronger chemicals. According to McDanel, that option would be a three to five million dollar project.
McDanel stated that People Services will also create a lake management plan to “ensure required protocol for monitoring of lake quality, temperature and other metrics used to identify a potential issue early on” to keep staff proactive instead of reactive in future situations.
McDanel will work up some potential projects to present to the council members for their consideration at a later date.
Residents who wish to contact staff can call the water treatment plant at 660.562.3713 or can look up the water sample data at www.dnr.mo.gov, using Maryville’s water plant code, 1010508.