Basement Flooding

Tired of Basement Flooding? Want to Be a Good Neighbor?


It is important that you understand why flooding has increased in recent years.  You also need to know the facts (rather than the myths) of basement flooding and Chicago sewers.  Finally, you need to be willing to work with your neighbors on meaningful solutions.

It’s Not Hard Or Expensive.  But, You Have to Care.

What Causes My Basement to Flood?

There is a new kind of storm hitting Chicago in recent years—heavy rains that can be very local, very intense and hard to predict.  They dump 2 inches or more per hour on a given neighborhood. This volume quickly overwhelms local sewers, which were not designed for such intense rainfall.  Sewer mains fill up, and additional water pushes into basements through our private drains.

There are two main sources for this additional rainfall.  The first is catch basins (CB’s) in the street.  These are the grated drains by the curbs that feed the main sewer through lateral pipes. 

The second is water from rooftops.  As much as 500 gallons of water can fall on the average residential rooftop.  In the old days, City code required that gutter downspouts be connected to private drains (PD’s) that carry domestic water to sewers.  This was fine for normal, old fashioned rains.  But, when sewers are full, the water has nowhere to go but your basement.  In essence, we are flooding ourselves.

The City is working hard to improve our aging infrastructure, but there are 4,400 miles of sewer main in Chicago, and mere replacement is not the answer.  The key is to keep as much water out of the sewer as possible during the heaviest rains. 

If we divert as much water as possible from our sewer system, we will spare ourselves some painful floods.  Nobody can guarantee you will never flood.  

What is the City's Responsibility?

The City can do a few things, including:

  • Placing restrictors—known as “Rain Blockers”—in CB’s all over town.  These plastic devices slow down the flow of water from the street.  It  goes into the sewer only as the sewer is able to handle it.  The streets are turned into temporary reservoirs (for 3-4 hours), and it gradually drains.  IF STREETS ARE FLOODED FOR A FEW HOURS, THAT’S GOOD.  IT’S BETTER THAN HAVING IT IN YOUR BASEMENT.  If the restrictors are missing, your sewer will surcharge and push water into your basement. 

Why Do My Neighbors and I Have to Act?

All flooding is local.  We are connected to each other by an underground network of open pipes.  If we do not act in concert, we are being unrealistic.

Much of the water flooding basements is traveling across private property.  Whether it’s your roof gutters or your yard, the City is not allowed to perform work on private property.  It is up to owners to make the appropriate changes to meet the challenges of new weather patterns.  And neighbors must work together to achieve good results.   


Do You Have Anything to Read, So I Can Talk to My Neighbors With Some Good Information?

Of course we do. 

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