Definition
A sewer is a system of pipes, channels, and treatment facilities designed to collect and transport sewage and stormwater. The primary functions of a sewer system are to remove contaminants from wastewater, manage rainwater to prevent flooding, and protect public health and the environment.
Examples
Example 1: Sanitary Sewer
A sanitary sewer collects wastewater from homes, commercial buildings, and industries for treatment and disposal at a public facility. This type of sewer handles such wastes as household effluents, greywater, and sewage.
Example 2: Storm Sewer
A storm sewer system is designed to collect and transport rainwater (stormwater) runoff from roads, sidewalks, parking lots, and other impervious surfaces to prevent flooding. The collected stormwater is often discharged directly into natural water bodies or managed through treatment options to remove pollutants.
Frequently Asked Questions (FAQs)
What is the difference between a sanitary sewer and a storm sewer?
A sanitary sewer carries wastewater from various sources (like household sinks and toilets) to a treatment facility, whereas a storm sewer transports stormwater from surfaces like roads and rooftops directly to a water body or a treatment facility.
Who is responsible for maintaining sewer systems?
The responsibility for maintaining sewer systems typically falls to local municipalities or water authorities. Property owners are generally responsible for maintaining the sewer lines connected to their properties.
How does a combined sewer system work?
A combined sewer system is designed to collect both wastewater and stormwater in a single pipe. This type of system requires extensive treatment facilities because the mix of stormwater and sewage can create large volumes of water needing processing, especially during heavy rainfall.
What are common problems that occur in sewer systems?
Common problems include blockages due to grease or debris, root intrusion from trees, pipe corrosion or collapse, and overflow during heavy storms. Regular maintenance and inspection are essential to prevent these issues.
Why is wastewater treatment necessary?
Wastewater treatment is crucial for removing contaminants and pollutants from sewage before it is released back into the environment. This process helps to protect water quality, public health, and ecosystems.
Related Terms
Sanitary Sewer
A network that collects wastewater/drains from buildings and transports it to treatment plants for pollution removal before releasing it into natural water bodies.
Storm Sewer
An infrastructure system designed to drain surface water runoff efficiently from streets, land, and impervious surfaces to prevent flooding and water pooling.
Combined Sewer
A sewer system that merges both stormwater runoff and sewage into a single pipe for transport to water treatment facilities, mainly used in older urban areas.
Wastewater Treatment Plant
A facility that processes sewage and wastewater to remove contaminants before discharging the purified water back into the environment.
Manhole
A covered opening into a sewer system to allow for maintenance and inspection.
Online Resources
- Environmental Protection Agency (EPA): Wastewater Technology
- American Society of Civil Engineers (ASCE): Sewer Design and Rehabilitation
- Water Environment Federation (WEF): Stormwater and Green Infrastructure
References
- Cloern, J.E., & Jassby, A.D. (2012). “Wastewater discharges and ecosystem functions of South San Francisco Bay, California.” Water Biology.
- Tchobanoglous, G., Burton, F.L., & Tsuchihashi, R. (2014). “Wastewater Engineering: Treatment and Resource Recovery.” McGraw-Hill.
- Metcalf & Eddy, Inc. (2003). “Wastewater Engineering: Treatment and Reuse, 4th Edition.” McGraw-Hill.
Suggested Books for Further Studies
- “Wastewater Engineering: Treatment and Resource Recovery” by George Tchobanoglous.
- “Water and Wastewater Technology” by Mark J. Hammer and Mark J. Hammer Jr.
- “Introduction to Infrastructure: An Introduction for Sustainable Community Development” by Samuel Labi.
- “Environmental Engineering: Fundamentals, Sustainability, Design” by James R. Mihelcic, Julie B. Zimmerman.
