Sanitary Sewer Collection System
Sewer Maintenance and Environmental Management System
The City of Raleigh Public Utilities Department provides the best wastewater services for our customers while protecting the environment and maintaining public health at a reasonable cost. The sanitary sewer system built during the 1890s discharged directly into Walnut Creek and Crabtree Creek without treatment; today’s system is much different. The sewer system consists of approximately 2,569 miles of mains which convey wastewater to one of three wastewater treatment plants. The City of Raleigh treats wastewater from approximately 183,000 customers in Raleigh and the surrounding communities of Garner, Wake Forest, Rolesville, Knightdale, Wendell, and Zebulon; serving a population of more than 500,000 people.
The maintenance of the sanitary sewer collection system is critical to the public health of our customers. The Sewer Maintenance Division of the Public Utilities Department is responsible for the sanitary sewer collection system maintenance. Sanitary sewer mains are primarily located underground; connected by a series of manholes that are either at or slightly above ground level. Employees must be able to access the manholes to maintain the system. Manholes are located in public right-of-way or in easements on private property. There are 2,569 miles of sanitary sewer mains in the City of Raleigh service area; approximately 1,009 miles located in easements on private property. The operation and maintenance of the sanitary sewer system is a protection of the capital investment that the community has made in its wastewater collection system, which extends its effective life cycle and reduces operational costs. Inadequate operation and maintenance of the sanitary sewer system can cause failures, which can result in sanitary sewer overflows.
What is the sanitary sewer system?
The sanitary sewer system collects the wastewater from your home or business and conveys it to a wastewater treatment plant for processing so that it can be returned safely back into the Neuse River or re-distributes as no-potable reuse water.
What could happen if the system fails?
If the sanitary sewer system fails, raw sewage can back up into homes or businesses or overflow onto the ground. Failures of the system can create public health, odor and sanitation problems.
What causes the sanitary sewer system to have failures?
The discharge of anything besides human waste, used water, or toilet paper can cause blockages in the sanitary sewer system that cause backup or overflows. The most common materials that cause blockages are grease accumulation or paper and cloth materials that are not flushable. Tree roots intruding into the pipeline and vandalism can also cause failures.
What is the City doing to prevent problems within the sanitary sewer system?
The City has a very proactive preventive maintenance program that includes routine cleaning of the mains by flushing; chemical treatment to the mains to help eliminate debris accumulation; and root, grease, and easement maintenance which includes mowing and tree removal. The City also has budgeted in the Capital Improvement Program significant funding for the replacement and rehabilitation of its aging sanitary sewer infrastructure.
Where are the sanitary sewer mains located?
The sanitary sewer mains can be located either in the public right-of-way (the streets roads) or on private property in dedicated sanitary sewer easements, typically along property lines.
What is a Sanitary Sewer Overflow (SSO)?
A SSO is the discharge of raw wastewater from the sewer system out onto the ground or into a waterway. This is a release of waste onto private property and adjacent creek or stream or, in the worst of cases, into a customer's home. These spills have various causes, the principal ones being the buildup of fats, oils, and grease as well as root infiltration. A solid maintenance program helps to prevent SSOs from occurring. The City of Raleigh experiences approximately 50 such occurrences each year despite our best efforts to prevent them. This is a comparatively low number given the amount of sewer lines in active service.
Sewer Maintenance Environmental Management System (SMEMS)
The City of Raleigh Public Utilities Department (CORPUD) Sewer Maintenance Division received certification for their Environmental Management System (EMS) in January of 2015, which was created to advance sound environmental performance by controlling the impacts of their activities on the environment. Sewer Maintenance developed this EMS to improve the environmental performance of its collection system management activities and demonstrate this performance to stakeholders. The Sewer Maintenance management system has been certified to the ISO 14001:2004 American National Standards.
An EMS is a management framework for integrating environmental considerations into day-to-day operations and decision-making, and for improving organizational performance over time.
“To professionally operate and maintain the sanitary sewer collection system, while meeting our compliance obligations, continually improving performance, providing environmental protection and pollution prevention.”
The Sewer Maintenance Division is committed to upholding this policy in the following areas:
- Manage assets and resources by setting goals, objectives, and targets for continual improvement.
- Communicate and educate stakeholders, interested parties, and staff
- Comply with applicable laws, regulations, and requirements
- Improve in performance, compliance, and system O&M for prevention of pollution.
Approved by: T. J. Lynch, Assistant Public Utilities Director for Wastewater