MOUNT VERNON — Mount Vernon Safety-Service Director Tanner Salyers explained improvements to “aging systems” related to water treatment and distribution at Monday night’s City Council meeting.
In a nutshell, Salyers proposed a request for qualifications about upgrades to lime slakers and silos for better water quality, a new water tower for better system pressure, and transitioning to a sodium hypochlorite disinfection system to help alleviate the controversial “washout” phenomenon.
“As we go through this, I would remind you that this is only for study and design, none of this is about construction,” Salyers said. “At the end of the day, we are only asking to issue an RFQ (Request for Qualifications) for study and design.”
Disinfection system plans
“This was the big one, and this one’s actually optional,” Salyers said before getting into the proposal for a new disinfection system.
Currently, Mount Vernon has a chlorine dioxide disinfection system. Below is how Salyers broke it down.
What is that? The system uses an oxidizing agent to eliminate bacteria, viruses and other microorganisms that can sometimes contaminate drinking water before treatment.
What does it do? It effectively disinfects water without producing a high amount of harmful byproducts, mostly found in surface water sources.
Why does the City use it? The system gives strong and consistent disinfection, producing safe, high-quality drinking water to Mount Vernon.
Why the possible change? “While our current system continues to operate safely and efficiently, external factors, particularly in the textile sector, and anticipated community growth, make it prudent to explore sodium hypochlorite as a more adaptable long-term solution.”
What’s a sodium hypochlorite system, and the difference between the two? The proposed new system would use a liquid form of chlorine to disinfect drinking water safely and effectively.
“The system injects controlled amounts of a solution into the water to kill bacteria, viruses, and other microorganisms, providing consistent and reliable disinfectant residual throughout the distribution system,” Salyers said.
In comparison, the sodium hypochlorite system is more common, easier to operate, store and regulate than other systems.
Mount Vernon is one of two cities in Ohio that still uses a chlorine dioxide system; the other is Hamilton, Salyers mentioned.
For potential drawbacks, “the chemical can degrade over time, requiring careful storage and handling, and it may slightly increase corrosion potential in pipes if not properly balanced,” Salyers stated.
However, these issues are manageable with up-to-date monitoring and treatment methods, and the same drawbacks can apply to a chlorine dioxide system.
Disinfection system as it relates to “washout”
“Washout” is caused by a chemical reaction between residual dye compounds from the textile manufacturing process and oxidizing agents in water or some laundry detergents and produces bleach-like spots on clothes, specifically cotton products, Salyers explained.
“If you are on a sodium hypochlorite system on well water, doing your laundry down in the creek, [which I] don’t recommend, and you use a laundry detergent that has an oxidizing agent in it, the same thing will still happen, because this is a chemical reaction,” Salyers said.
When an oxidizing agent comes in contact with a sulfur dye and the dye isn’t properly bonded, washout occurs, and whatever water is used doesn’t matter.
The difference in Mount Vernon’s case is there is an oxidizing agent in the water from the current disinfection system. The oxidizing agent in the water is “totally fine” and “totally safe,” he said.
The problem comes from changes in textile manufacturing, not people doing their laundry wrong, a washing machine malfunctioning, an issue with the City’s water, or even the retailer selling the washed-out item, Salyers detailed.
“Recognizing this and understanding that Mount Vernon is one of only two public water systems in Ohio that use chlorine dioxide, it is prudent and forward-thinking to explore a sodium hypochlorite disinfection system that achieves the same public health protection without contributing to this washout effect,” Salyers said.
Development benefits of going to sodium hypochlorite
Below is the exact sheet Salyers used when explaining additional benefits to switching to a sodium hypochlorite disinfection system.
Lime slakers and silos
There are four key challenges the lime system faces in Mount Vernon, according to Salyers:
- Existing lime handling equipment is outdated and undersized.
- Increased maintenance costs and operator time.
- Aging and deteriorating equipment requires more time, more product and more money.
- Lime feed inconsistencies could potentially impact water softness (water feels smoother and cleaner because it doesn’t have a lot of minerals like calcium and magnesium in it).
So, how does the City propose resolving these issues?
“What’s proposed is installing two modern lime slakers for precise mixing, add dual lime silos for storage and automated feed,” Salyers said.
The Safety-Service Director went on to say the current plant already has one of the dual silo systems in place.
Additionally, the plan would also “enclose [the] system for dust control and safety.”
Salyers’ presentation says these upgrades “improve water quality stability, reduce maintenance and chemical waste, and enhance operator safety and efficiency.”
City Council President Bruce Hawkins asked the million-dollar question, “Define slaker, what does a slaker do for me?”
“A lime slaker, our particular ones that we have, have a silo above it [that then] comes down to a cone, and the lime is then almost like a water softener salt that feeds into the water, and it mixes, creates a slurry. Then, it’s slaked and goes on to the clarifier,” Public Utilities Director Aaron Reinhart answered.
Salyers noted the current system pumps the slurry up into the clarifier, and a new design would feature a gravitational feed to be more cost-effective and efficient.
Distribution limits & new water tower solution
Noting Liberty Crossing’s development, Salyers addressed water distribution issues in the southern service area.
Currently, the area “relies on system pressure from the water treatment plant,” Salyers said.
This system produces limited redundancy when demand is high or during maintenance. Additionally, the growing neighborhoods and commercial areas need proper planning for capacity and fire flow concerns.
Salyers proposed a new water tower capable of handling up to 1 million gallons.
“[The tower would be] strategically located near the Industrial Park on Newark Road or near the Twin Oak property,” Salyers said.
“The pressure zone is dependent. We’d look at studying the current pressure zone, and we would integrate with modern SCADA for system control and monitoring.”
Salyers listed the following as benefits of this project:
- Improved system pressure and reliability.
- Enhanced fire protection.
- Support residential and commercial growth.
- Reducing the strain on the downtown infrastructure, specifically the water plant.
Funding
Below is the sheet Salyers read from while discussing the proposed project’s funding with the Council.
However, not on the sheet, Salyers added the following statement right after the final bullet point.
“But I would recommend, based on just what we’ve heard from the community, that this would be something that the public would be willing to support.”