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      Department of Public Works Bureau of Sanitation


Many Los Angeles residents may not be aware of a potential connection between the municipal sewer system, and the storm drain-flood control system. While these two drainage systems are totally separate, in the event of heavy rains these systems can intersect with negative consequences.

Normally, the Los Angeles sewer system can easily handle the demands of not only the city’s 3.9 million residents, but also treats the wastewater coming from the cities of Glendale, Beverly Hills,

This photo taken by a remote-controlled camera shows a sewer line clogged with accumulated grease.

The City of Los Angeles is asking residents
to minimize or reduce the amount of
cooking grease poured down sinks.

Heavy rainfall runs off of city streets and enters sewers through vent holes in the maintenance hole covers.

As the system is inundated with higher than normal flow from the rainfall, the grease blockages can create backflow conditions and the result is rainwater mixed with sewage to overflow out of the sewer maintenance covers.