sewer-iconThe IRWD sewer system collects wastewater from homes and businesses within the service area. Sewage travels through the collection system and is conveyed to two treatment plants through more than 900 miles of sewer distribution pipelines. The Michelson Water Recycling Plant in Irvine treats up to 18 million gallons of wastewater per day and the Los Alisos Water Recycling Plant in Lake Forest treats up to 5.5 million gallons per day.  This treated water is then put into the recycled water system for irrigation and other uses in the community. Every drop of recycled water used, helps to save a drop of drinking water.


Sewer System Management Plan

The SSMP is a plan and schedule for the maintenance, operation and management of the sewer system.

IRWD Sewer Management Plan
IRWD Sewer Management Plan Appendices

 Storm Drains

 Storm drains are a completely different system. Storm drains collect rain water and other urban runoff from the community. This water travels through street gutters to storm drains, which in our area channel the runoff to San Diego Creek and eventually to the ocean. Storm drains are not the responsibility of IRWD. Within city limits they are the responsibility of the city government; in unincorporated areas they are  the responsibility of the County of Orange. It is important to remember that water from storm drains does not go through a treatment plant for cleaning. Any trash or pollutants thrown into the street or storm drains will eventually reach Newport Bay and the ocean. Citizens can do their part by not overwatering their landscaping, thereby reducing the amount of unnecessary runoff that reaches the ocean. And, of course, don't litter.

 Sewer Laterals - Who's Responsible? 

Most homeowners don’t tend to think about sewers until there is a backup in their plumbing. Anyone who has ever had a sewer backup would agree it is an unpleasant problem that can be costly if ignored. If you find that your drains are moving slowly, that’s an early indication that there might be the beginning of a blockage.

Often, the question arises – where does the responsibility of the customer begin and end and when does it become the responsibility of IRWD? The upper sewer lateral – the line leading from the residence to the edge of the property line – and the lower lateral, which connects into the sewer mainline, is the responsibility of the customer to maintain. In addition, customers are responsible for making any repairs to the upper lateral only. If repairs are needed on the lower lateral, that is the responsibility of IRWD.
A typical sewer system is constructed of a network of pipes connecting to each building and transporting wastewater to IRWD’s two wastewater recycling plants. Sewer clogs can lead to sewer spills. There are many ways to prevent such spills:

  • Never put fats, grease or oils down drains, garbage disposals, or toilets. Instead, place oils into a jar or can and throw it into the garbage can for collection.
  • Do not put disposable rags or wipes down drains or toilets. Even if the product claims to be “flushable,” it is not and causes clogs and damage to sewer pumps.
  • Do not plant trees or shrubs near sewer laterals because root intrusion can cause serious blockages and damage to the lines.
  • Perform periodic cleaning and inspections to your sewer laterals to ensure the lines are running free and there are no clogs or root intrusions.

IRWD crews are a good source of unbiased information and are always available to help our customers decide on a course of action. All you need to do is contact us if you have questions.

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