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Catch Basins (CB's)

Standard catch basinCatch basins are storm grates found along the side of the road or occasionally in backyards.  They allow rain water and snow melt to enter the storm sewer system.  The City of London has almost 29,000 catch basins.  Although catch basins within the road allowance are maintained by the City of London, it is a good idea to make sure the catch basins in your area have not been blocked with leaves, snow/ ice or other debris.  When leaves and debris cover the catch basin(s), the water on the road has nowhere to escape and can cause increased ponding on the streets or even make its way onto private property such as the front lawn.


Curb inlet catch basin (CICB)Curb Inlet Catch Basins (CICB)

A curb inlet catch basin is similar to a standard catch basin (shown above).   CICB’s are normally used on arterial roads or low points on the street.  The water enters through the grate on the road as well as the opening on the face of the curb.





Overgrown rear yard catch basin


Rear Yard Catch Basin (RYCB)

The catch basins found in backyards (RYCB’s) are generally the responsibility of the home owner to maintain. They are typically at the low point of the property and possibly take flows from multiple properties.  In order to have your RYCB function properly keep grass, weeds, debris, leaves, etc. from blocking the catch basin cover.  This RYCB (shown right) is so overgrown that it is hard to see.  When the cover of the catch basin is even partially obstructed water has no choice but to pond on the surface.


Rear yard catch basin with no obstructionsNote: Gardens, sheds, pools, fences, etc. should not obstruct the drainage pattern (overland flow route) of the water trying to get to the RYCB. When these obstacles are in place, water is forced to pond or find an alternate flow route which could be to your basement window.  For more information, refer to the "Preventing Flooding" Catch Basin Brochure.






Old style catch basinOld Style Catch Basin

Some older areas in the city may have catch basins smaller than the catch basins used on newer streets.  They are approximately the same width as the gutter. They function the same as a standard catch basin. Because the grate for the older catch basins is smaller, it is more important to ensure leaves, snow, and debris do not accumulate over top of them. When a street and sewer system is reconstructed, the City will install the larger, newer style catch basins on that street.

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