While the visible impacts of rain — like fallen branches, clogged gutters, or puddles in the street — are easy to see, impacts on the sewer system often go unnoticed until problems arise. During a storm, rainwater can make its way into your local and regional sewer systems, like the Orange County Sanitation District’s (OC San), through a process called inflow and infiltration. Inflow occurs when rainwater finds its way into sewer pipes through small openings, like holes in manhole covers, while infiltration happens when groundwater seeps into small cracks in sewer pipes.

Though it may not seem like a lot, this extra water can quickly add up. On a typical day, OC San collects, treats, and recycles about 190 million gallons of wastewater. During a storm, this amount of wastewater can double! Too much water in the system can lead to clogs, back-ups, or even messy spills.

So, what can you do? By waiting until after the storm passes to do water-using chores like dishes or laundry, you can reduce strain on the sewer system. If the rain doesn’t seem to let up, try holding off on laundry or running the dishwasher until after 6:00 p.m., when wastewater flows are lower.

By taking these small steps, you can help keep your local sewer system and OC San running smoothly this rainy season.