Wastewater Capacity in Union County

June 7, 2024

Infrastructure: The Foundation Business Is Built Upon - Wastewater Capacity in Union County

We are continuing our blog series on the importance of infrastructure investment with a further look at wastewater (or sewer) management in Union County.  Today we’ll talk about the system managed by the County and how our capacity is determined.

Wastewater Management in Union County

Before wastewater can be treated, it has to be moved from your business or home to a treatment facility. Union County is responsible for a vast network that handles this used water. The system consists of:

      • Gravity Lines: Over 540 miles of gravity lines use the natural pull of gravity to convey wastewater from local properties to the treatment facilities. These lines are carefully sloped to ensure a seamless flow without mechanical assistance, making them an energy-efficient component of the infrastructure.
      • Force Mains: More than 70 miles of force mains are essential in areas where gravity alone cannot ensure the flow of wastewater. These pressurized pipes, aided by over 70 pump stations, propel wastewater out of valleys, over hills and long flat distances to reach treatment facilities, ensuring that every part of our community is serviced, regardless of its topography.

These facilities are designed to treat wastewater from specific areas, ensuring that the water returned to our environment is clean and safe.

Capacity and Concerns 

Currently, Union County has a permitted capacity of 9.65 million gallons per day. To supplement this, the county has agreements with the Cities of Monroe and Charlotte, adding an additional capacity of 5.65 million gallons per day. Since treatment facilities are heavily regulated by the Department of Environmental Quality, you won’t be surprised to learn that the formula for determining a plant’s available capacity is more complicated than simply measuring the amount of water the plant can treat compared to what is actually treated. This capacity is crucial in determining how much new development can occur—be it commercial, industrial, or residential. A lack of capacity could potentially halt new business developments and expansions, directly affecting local economic growth and opportunities. 

Impacts on Capacity

You may know that water from storm drains does not flow into our sewer system, but rather directly to our streams and lakes. That is why residents are discouraged from dumping chemicals into the storm drain.  Even so, did you know that rain does increase the amount of wastewater that flows into our treatment plants? With more than 600 miles of pipes, ground water finds its way into our stormwater pipes through small cracks, and imperfectly sealed joints and seams. 

Our available capacity is also reduced by approved but not built development.  When a new industrial facility or residential neighborhood is approved, the county must set aside capacity to treat the wastewater that new development will produce. The exact amount set aside is set by the state, and, erring on the side of caution, the state typically requires more capacity to be set aside than the new construction will actually produce.  Ironically, this means many new developments “use” less treatment capacity once they are built than they “use” when they are simply planned.

What’s next?

Now that you have an understanding of how capacity is determined and what impacts it, we’ll explore the specific numbers in Union County in our next blog post.

Last modified: June 7, 2024

Comments are closed.