No, the wastewater conveyance system, pump stations and the wastewater treatment plants are designed to handle peak flows that occur during high-volume days. Additionally, our wastewater plant operators to take steps within the plant itself to modify operations to most efficiently process the increased flows.
The biggest impact on daily flow is rain. Rainwater seeps into our sewer pipes and increases the amount of water flowing to the wastewater plants. Preparations are made to accommodate this additional water when heavy rainfall is forecast.
You can report any concerns to the Water and Sewer Authority (WSACC) at 704-786-1783 and we will investigate. The Water and Sewer Authority is required to monitor treated wastewater that is being discharged from the plant on a daily basis. We maintain a state certified laboratory and conduct testing throughout the day to insure we are meeting permitted limits on discharges. The Water and Sewer Authority retains an excellent record of compliance.
The state of North Carolina requires wastewater treatment plants to plan for houses and other buildings that have been allocated but not built and count their projected wastewater against the plant’s capacity. A rapid increase in new flow allocation requests in Cabarrus County has rapidly increased the amount of wastewater projected to be produced in the coming years.
Cabarrus County has been experiencing new flow allocation requests at a much faster rate than homes have actually been built resulting in the amount of flow that has been allocated but not yet built almost doubling over the past 5 years.
Currently the Rocky River Regional facility has 2.87 million gallons per day allocated for new construction but not used and 2.66 million gallons per day available to be allocated.
Unfortunately, it’s not. The biggest variable for average daily flow is rainfall. Rainwater seeps into the wastewater system and increases the amount of water that must be treated. Over the last five years, the biggest increase in average daily flow occurred between 2017 and 2018.
WSACC and its member jurisdictions operate over 3000 miles of sewer lines, over 40,000 manholes and over 100,000 sewer connections throughout the service area. All of these lines, manhole and sewer cleanout connections allow for access points for rainfall and groundwater to enter the sewer collection system. During very wet periods of time this rainfall and groundwater can significantly increase the flows within the wastewater system.
As you will see from the chart below, based on historical increases, the facility was projected to have 29 years’ worth of growth capacity as late as 2017. In 2018, the actual flow to Rocky River Regional increased by the same amount as it had the previous 10 years combined. As soon as this data was available, the staff and board of the Water and Sewer Authority began planning for an expansion of Rocky River Regional.
Here is the data that the Water and Sewer Authority was looking at.
Note that from 2013 to 2017, the actual and allocated daily flow grew by less than 500 thousand gallons per year, and at that growth rate, the Rocky River facility had adequate capacity to handle growth for decades.
Two years of historically high rainfall in 2018 and 2020 tilted the long-term trend line steeper. After the rapid increase in 2018, the Water and Sewer Authority began planning for expanding its treatment capacity.
Planning began in 2019 to add an additional 3.5 million galllons per day by 2024 and another 4 million gallons per day by 2027. Construction has already begun on that project using an innovative design/build process. While the typical timeframe for an expansion of this size is 6-8 years, this project will be completed in less than five years. Additionally, the Water and Sewer Authority has begun a long-range master planning process to plan for all water and sewer needs in the county for the next 20 years.
The Water and Sewer Authority has taken several steps to insure that allocated capacity accurately reflects the actual amount of wastewater that a new residence will require. The Authority successfully petitioned the state Department of Environmental Quality to lower the projected amount of wastewater per bedroom for a new residence from 120 gallons per day to 80 gallons per day. However, this required projection is still significantly higher than what the Authority believes will be actually produced and higher than the requirement for other systems in the region, such as Charlotte Water.
The Authority is working with other local governments to confirm when housing units are occupied so that a housing unit isn’t counted as a permitted/allocated unit and producing actual flow at the same time.
The Authority is also working with the Department of Environmental Quality to allow permitting against the future actual capacity for development projects that will not be occupied prior to the expansion project completing in 2024.
No, the Water and Sewer Authority and the governments that it serves have entered into an interlocal agreement so that the municipalities can decide how best to allocate the remaining capacity at the Rocky River facility. Previous to entering this agreement, the Water and Sewer Authority approved permits on a first come – first served basis
Water and Sewer Authority of Cabarrus County
232 Davidson Highway Concord, North Carolina 28027