All posts by Cam Coley CLTWater Communications

Construction, Repairs and Spills

How Does CLTWater Respond To A Wastewater Overflow?

First, what is a wastewater overflow? A wastewater overflow, also referred to as an SSO (Sanitary Sewer Overflow), is a release of untreated or partially treated sewage from a municipal sanitary sewer, typically out of a manhole or a broken pipe.

Taken by Cam Coley, employee City of Charlotte, Charlotte Water

While wastewater overflows are nearly inevitable in a system as large as Charlotte’s, we do our best to keep these incidents to a minimum to protect human and environmental health.

How can I tell if there is a wastewater overflow in a creek?

You may notice a gray, milky color or odor. If you do suspect an overflow, call 311 right away and say or select wastewater emergency, and a crew will respond.

What should I do if I see a wastewater spill?

Call 311 or 704-336-7600 and say or select sewer emergency. We will respond 24 hours a day.

How can I help reduce overflows? 

  • Toss in the trash: paper towels, wipes, hair, cotton swabs, feminine products, dental floss, coffee grounds, and excess food. 
  • Toss in the toilet: only toilet paper. 
  • Drain in the sink: soap suds, small amounts of food from the plate, and liquids. 
  • Take to a full-service recycling center: used and expired oils and grease. 

What causes wastewater overflows?

  • Clogs from wipes, paper towels, leftover kitchen grease, oils, or anything other than toilet paper.
  • Pipe failure (tree falls and breaks pipe, stream/creek erosion causing the pipe to fall into the creek)
  • Tree roots attacking and clogging the pipe
  • Damage by nearby construction. (Reminder to always call 811 before you dig.)

How does CLTWater respond?

A rapid response crew will investigate the area and attempt to remove the clog. This work does not impact drinking water quality. Crews may run hydrants to flush the area, lightly apply lime to sanitize, and/or return to investigate other pipes. Residents and their pets are encouraged to avoid contact with the creek during an overflow response.

How does CLTWater respond to a large overflow?

There is a myriad of responses depending on the situation. For example – a tree falls into the creek, washing out the creek bank and undermining the wastewater pipe just behind the creek bank. Crews frequently inspect these areas, but erosion can occur quickly during heavy rain events. Crews will:

  • Create a temporary access road or path if necessary to respond.
  • Install a temporary wastewater pipe to bypass the broken pipe and stop the overflow. The pumps and temporary above-ground pipes are checked several times daily to prevent possible wastewater overflows.
  • Stabilize the creek bank.
  • Construct a barrier / temporary stream bank to protect workers.
  • Remove the broken pipe. 
  • Install the new pipe and test it.
  • Rebuild the stream bank with clean fill material (soil). 
  • Remove temporary pipes and pumps.
  • Remove large spoil piles of dirt.
  • Complete grading/drainage.
  • Plant trees/shrubs and seed/straw the area.
  • Restore the stream bank and revegetate.
  • If the greenway was closed during work, it would be restored and reopened. When greenways are affected, CLTWater works with Mecklenburg County on restoration.

How does CLTWater handle tropical storms or heavy rains and prevent spills?

The underground sanitary sewer pipe network is not designed to handle rain, yet the runoff and flooding from large rains inevitably infiltrate the wastewater pipe network. Overflow basins at the five largest wastewater treatment plants capture and later treat more than 160 million gallons of rainwater mixed with wastewater. These equalization basins (EQ basins) prevent wastewater from overflowing out of manholes in our community.

CLTWater has also added several large wastewater pipes to help reduce the impact of heavy rains. Crews work to prevent rainwater from getting into the sanitary sewer system and are out investigating our system soon after a storm ends.

Additional Resources:

Wastewater treatment plant process

Why does wastewater cost more than water on my bill?

How does CLTWater respond to a wastewater overflow?

What does a growing city mean to wastewater treatment plants?

Is the odor from a wastewater plant or sewer manhole?

Billing, My Water

Filling, Refilling, or Draining a Swimming Pool         

Need to fill a pool in Charlotte, Cornelius, Davidson, Huntersville, Matthews, Mint Hill, or Pineville? You have options…

Option 1:

Call swimming pool installation or pool supply companies to get referrals of companies who fill swimming pools. Search online for ‘swimming pool water charlotte,’ or check yellow pages under ‘swimming pools’ or ‘street cleaners.’ Consider getting more than one price estimate. If a contractor has to haul the water, it could cost a lot so make sure they explain all costs.

Option 2:

Fill from outside spigot using an existing water service.

Check past bills to calculate typical water use and how much it would cost to fill or refill the pool.

If it is an empty pool, consider filling it up halfway on one 30 day bill cycle and then fill the last half during the next billing cycle. Sewer charges apply up to 16 Ccf.

*1 Ccf = 100 cubic feet or 748 gallons of water

Option 3:

Rent a hydrant for two days if;

•            hydrant is in good working order.

•            hydrant is on your side of the street and wouldn’t restrict access to neighbor’s driveway.

•            you need at least of 15,000 gallons or 20 Ccfs.

Service requires a charge for a technician to connect water quality protection equipment and activate hydrant for rental and turn off after two days. Additionally, water consumption will be billed at the current commercial (non-residential) water rate.

Customer is required to rent or purchase an approved hose, from an independent supplier, to connect to the hydrant.

Please call (704) 400-2844 for additional information.

Option 4:

Apply for a separate water meter installed just for filling a swimming pool. View application and fees. Swimming pool meter charges start at tier 3 rate depending on amount of water used during monthly billing cycle.

How do i drain a pool?

Drain to Yard or Landscaped Area

A good option is to drain water to your yard or landscaped area if and only if you:

  • Do not cause flooding or other nuisance conditions on adjacent properties (notify your neighbors first).
  • Drain at a rate slow enough to not cause erosion.
  • Drain at a rate slow enough and to an area that allows the water to percolate into the ground and not discharge into the storm drain system, ditch or creek. This may be difficult to do because most properties are designed to drain off site. If discharge into a storm drain or water conveyance may occur, then you must follow the practices listed under “Drain to Storm Drain System”.

Drain to Storm Drain System

  • You may drain water from your pool or spa into a storm drain, ditch or creek if and only if you:
  • Dechlorinate the water below 0.1 milligrams per liter by allowing it to sit for one week without adding chlorine or by using a chemical dechlorination additive. Test the chlorine level with a pool testing kit before discharging.
  • Do not add other chemicals for at least one week before draining.
  • Ensure the pH of the water is between 6 and 9.
  • Remove or strain out algae and debris.
  • Discharge at a rate slow enough to not cause erosion.
  • Saltwater pools and spas may never be discharged to the storm drain system because of high chloride levels. You must choose another draining method if you have a saltwater pool or spa.

Drain to Sanitary Sewer System

  • You may drain water to the sanitary sewer system as a last resort if and only if you:
  • Contact Charlotte Water – System Protection to obtain authorization at 704-336-4407.
  • Follow all requirements provided by the person you talk to at Charlotte Water.
  • Do not discharge filter backwash to the storm drain system, but rather to a landscaped area or sanitary sewer. Some pool filters have a direct connection to the sewer system.
  • Dispose of filter material and collected debris in the trash.
  • Rinse filters over your lawn or landscaped area.
News, What's Going On?

CLTWater Delivers Water Pressure During Massive Fire In SouthPark

On May 18th, Charlotte experienced one of the largest fires in the city’s history. Charlotte Water (CLTWater) responded with

  • Managers on location to assist with any water supply needs,
  • Operators pumped more water to the area,
  • Crews were on hand to assist if there were any water supply challenges.
  • Crews surveyed the area looking for and responding to water main breaks.
    • Water main breaks are likely after a massive flow of water is used for fighting fires.

Thank you to all that assisted in the response to ensure there was enough water supply and pressure for the Charlotte Fire Department (CFD) response.


“The partnership with the Charlotte Fire Department started more than 100 years ago and it is a weekly and sometimes daily coordination that enables us to assist in this crucial public safety role,”,” said Angela Charles, Director of Charlotte Water. “The investment in our water infrastructure has been instrumental in maintaining water supply and water pressure to serve our growing community and public safety needs.”

Charlotte Water Director Angela Charles coordinating with the Charlotte Fire Department during the fire.
My Water, Wastewater

What is a Backflow Prevention Assembly? Why does my house have a backflow preventer?

As we move into the summer months, it’s good to know how different aspects of your yard and lawn maintenance can impact our water system.

A photo of the backflow prevention assembly cover and a photo of the assembly with the cover behind the assembly

If your home has an irrigation system, it is required to also have a backflow prevention assembly. A backflow prevention assembly is typically part of an irrigation system or commercial property.

This is an important step to protect the drinking water supply in your neighborhood. A backflow prevention device ​prevents hazardous substances (i.e. chemicals used for lawn improvement or soil borne bacteria and parasites) from inadvertently being drawn into the drinking water system and contaminating it. 

If you have any questions or if we can assist you, please call 311 or 704-336-7600. Thank you for your cooperation.

Commonly Asked Backflow Questions

How often do I need to have my backflow tested?

Annually. A list of approved testers is listed on our website.

How do I know when is my backflow test due?

It is due the same time each year unless a deferment is granted. We check the last time it was tested and provide that information in the annual “Test Letter.” We can provide that to the customer by phone.

Is backflow testing performed by Charlotte Water?

Charlotte Water only performs an initial installation inspection and any follow-up required. It is the responsibility of the water customer to get the backflow assembly tested. For a list of approved testers, please see a list on our website.

How much does a test cost?

Charlotte Water does not set pricing for backflow assembly testing. Customers need to ask individual vendors what their charge is for testing their backflow assembly.

My residential irrigation system backflow is due for testing in December, can I delay testing until the spring?

Yes, please contact Charlotte Water for a deferment on the testing date. We recommend you have your assembly tested in the spring once the irrigation system is reactivated following winterization.

I have a backflow and so does my neighbor, however, my neighbor has never received a testing notification letter, why?

Your neighbor installer may have not contacted Charlotte Water about the installation of the irrigation system.

Where is my backflow?

It is the responsibility of the water customer to know the location of the backflow prevention assembly for their water system. Charlotte Water has locations based on initial inspection details.

My backflow needs repairs, do I need to hire a licensed plumber to make the repairs?

Yes, a licensed plumber is required per the N.C. Plumbing Board. You should hire a licensed plumber or professional who has expertise in repairing backflows. 

What is the difference between a backflow inspection and a backflow test?

A backflow inspection is an onsite visit by a Charlotte Water Backflow Inspector, making sure the assembly is installed properly.  A backflow test is to make sure the assembly with working properly. Charlotte Water does not perform backflow tests for its customers.

I understand backflows are for high hazard facilities such has hospitals and mortuaries, however, why do I need one on my residential irrigation system?

Irrigation systems can encounter contact with fertilizer, pesticides, and feces, which are high hazards.  A Reduced Pressure Principle Assembly (RP) backflow is used for high hazards.

I have a double check valve assembly (DCVA) backflow that needs replacing for my lawn irrigation system, can I replace it with another DCVA?

No, per Charlotte Water ordinance, the correct backflow preventer for irrigation must now be an RP(Reduced Pressure Principle Assembly). This applies to new installation and replacing a backflow on an irrigation system.

My irrigation system is no longer in use, do I have to test it?

Annual testing is still required until a licensed plumber has capped off your water service at the connection and removed the backflow prevention assembly. An inspection by a Charlotte Water Backflow inspector is required.

Installation Questions and Answers

Do I need a plumbing permit when installing a backflow?

Yes, please contact the Mecklenburg County Code Enforcement at (980)314-2633, You will also need to complete a backflow service application.

Do I qualify for a branch of my irrigation system from my domestic service without a separate water meter?

The Plat date determines if you qualify. The property must be platted prior to 2009. Research and provide the information with the Meter Deferment application.

Where do I send the Backflow Service Application? What is the fee for a new irrigation meter?

Please send backflow/meter applications and fees to:

Charlotte Water

C/O (NAME OF DEPT)

5100 Brookshire Blvd,

Charlotte, NC 28216.

Please contact New Services at (704)336-7600 for any questions regarding fees for water taps and meters.

I have a building project under construction and just had my backflow tested, however, I still have a project hold, did I do something wrong?

You need to contact the backflow inspections department at (704)391-5188 and see if there are additional holds for a backflow inspection.  Inspector needs to ensure the installation of the backflow. Ten days after the backflow inspection the backflow assembly needs to be tested by a Charlotte Water Backflow Approved Tester.

The meter and backflow were installed, and the installer left the meter cover open, so I wanted to know do we close it or is somebody else coming back to close it?

Please call the backflow inspection department for the inspector needs to ensure the installation of the backflow.