Understanding the Cost of Sewer Service
Sewer service has long been underfunded across the country with rates that do not meet the actual cost of providing the service to produce clean and reliable water. The payments that Nevada County Sanitation District customers make for sewer service pay for the operation, maintenance, and improvement of the District’s Wastewater System.
Taking care of what we have.
When it comes to maintaining the pipes and treatment plants for wastewater across the country, the United States fails as a whole, earning grades of D and D+ in the 2017 Infrastructure Report Card from the American Society of Civil Engineers. In California, the grades are slightly better — with a C- for wastewater infrastructure, according to the most recent state report card in 2019. Nevada County Sanitation District strives to do better.
The approach the District takes to its operations includes taking care of what it has. The sewer system, includes the treatment plants, pipes, other equipment, and employees who operate and maintain the system. Your sewer bill reflects your contribution to the labor and the physical infrastructure required to have wastewater removed and safely returned to the environment in a form that protects life and downstream water supplies. The District does not make a profit from providing sewer service nor does it use sewer revenue for other purposes.
Sewer service is expensive to provide. The main costs are:
• Wastewater Treatment • Pipes and other infrastructure • Labor
At our larger treatment plants, the treatment process for wastewater includes various stages of filtration, aeration, and clarification to remove trash, organic materials, and nutrients — such as nitrogen and phosphorus — that are harmful to aquatic life in large supplies. The water goes through a final fine filtration to remove any remaining solids and is then disinfected with ultraviolet light. The water quality is constantly monitored, and the water is pumped back into several local waterways, or in some cases land application. Trash removed during the wastewater’s first filtration stage is washed, compacted, and disposed of. The organic material filtered from the treated water is treated chemically to remove contaminants and to thicken the material. Water content is then pressed out, and the remaining organic material is transferred to a tractor-trailer truck for delivery to a local landfill for disposal. The wastewater left after washing the removed trash and pressing the removed organic material is piped back through the plant’s various filtration stages.
Pipes and other infrastructure
The extensive network of pipes, valves, pumps, and tanks used to deliver wastewater from the community to the District’s treatment plants for treatment need constant maintenance to ensure water runs smoothly and safely:
• The collection system, which collects wastewater and transports it to the wastewater plants for treatment, is made up of about 110 miles of pipe, 1,101 manholes, and 34 sewage lift stations.
• NCSD’s treatment systems, are made up of 10 Wastewater Treatment Facilities. These vary in size, capacity, and complexity depending on the size of the treatment zone. Combined they are responsible for treating around one million gallons of wastewater every day.
Each year, staff hydraulically cleans (450,000 linear feet) and inspects (40,000 linear feet) of the gravity pipes in the utility system. Inspections are performed by camera, dye, and smoke testing to locate areas where the lines are failing or need maintenance.
Although gravity is the most cost-effective way to transport water, pump stations often are necessary to boost pressure and to keep sewage flowing in low areas. NCSD has more pump stations than a typical municipality. The pump stations are expensive to operate, and failures can result in sanitary sewer overflows and fines from the State.
To ensure treated water quality is compliant and consistent all day every day, the utility system must be staffed with highly trained employees who must be on call for any situation that affects the quality or conveyance of wastewater. These jobs are demanding in their scope of responsibilities — from daily troubleshooting to system emergencies. NCSD staff are on call and ready to respond to sewer-related emergencies 24 hours a day, every day of the year.
NCSD has a Supervisor and five State Certified Wastewater Treatment Plant Operators to maintain all 10 sewer treatment facilities. Its wastewater collection division includes a Supervisor, and 7 Wastewater Service Workers responsible for cleaning and repairing sewer lines, maintaining pump tanks and sewage lift stations. Finally, we have three Electrical/Mechanical Workers that are responsible for preventative maintenance and assistance to both the Operations and Collections Divisions in performing critical repairs. All these positions require training, certifications, and up-to-date, in-depth knowledge of best practices and regulations — not to mention compensation.
The team that makes up the Sanitation District is very good at what they do. They take pride in their work and their role in protecting the community and our recreational waters. As a team, they are more efficient. They are working more efficiently than at any point in the history of our District and they are to be commended. Part of what allows that to happen is having the ability to purchase the right tool or piece of equipment for their current job. This allows the District to not only be efficient but also ensures that our staff is safe in an already hazardous occupation.