Pothole repairs

CDOT crews repair potholes on 3,800 miles of streets in neighborhoods throughout the city all year long.  The months of December through April are considered the heart of the pothole season--when the city typically sees the highest number of potholes.  However, crews work throughout the spring, summer and fall as well.

CDOT uses several techniques that enable the department to fill hundreds of thousands of potholes each year .  They include:

  • Computerized mapping and tracking of potholes reported to the City’s 311 system
  • Seven-day-a-week deployment of pothole repair crews during the winter months, including weekend crews and an overnight crew
  • The use of high-performance cold-patch asphalt material for pothole repairs during the winter months and hot mix asphalt in spring, summer and fall. 


Frequently Asked Questions About Potholes

What causes potholes?
Potholes are caused by the freeze-thaw cycle.  When moisture seeps into pavement, it expands when it freezes and contracts when it thaws.  This flexing of the pavement, combined with the melted water and the stress of vehicular traffic, causes pavement to deteriorate and potholes to form.

Where do potholes occur?
Chicago has more than 3,800 miles of streets, and potholes can occur on any one of them.  Potholes tend to appear most on arterial streets (which carry the most vehicles) and under bridges and viaducts, areas where water often collects.

How does CDOT battle potholes?
CDOT has an aggressive program to tackle potholes.  The department uses a computerized mapping and tracking system to identify pothole locations and schedule crews most efficiently.  Each morning, CDOT's pothole command generates a map of potholes reported to 311.  Using that map, managers determine routings for each crew that will allow them to fill the most potholes possible.  Night and weekend crews repair high-traffic areas when traffic is lightest, which maximizes efficiency and minimizes traffic impacts.

How many potholes does CDOT fill a day?
That varies daily, depending on the weather.  On days when weather is cooperative and there's no precipitation, crews can fill several thousand potholes. Falling snow or freezing rain severely limits the ability of crews to make repairs, and limits the effectiveness of the asphalt patching material.

How long does a pothole repair last?
It depends on many factors, including traffic volume.  Repairs can last a few days, a few weeks, a few months or more.  CDOT uses a high-performance cold patch material formulated to maintain its workability longer, particularly in colder temperatures.  This allows the material to properly fill the potholes and allows for better compaction.

What should I do when I see a pothole?
The public is encouraged to use Chicago’s 311 system to help identify street and alley locations that need the attention of pothole patching crews. City residents can report potholes through one of the following methods: Using the website 311.chicago.gov, CHI311 mobile app, or simply calling 311.  When a crew arrives to repair a 311 pothole, it fills all the other potholes nearby.

How long does it take to fill a pothole?
It varies, but repairs are generally completed within 3-6 days from the first report of a pothole to 311.  Weather influences how long a repair takes--especially when frigid temps and precipitation prevent our full force of crews from performing repairs.  The location of the pothole also influences the time required to repair--arterial streets are completed before residential streets.  During peak winter months, duration times usually rise.

Is every hole, dip, crack or break in the street considered a pothole?
No.  There are different kinds of pavement problems which require different solutions.  Potholes are typically irregularly shaped holes of varying depths. Sinking pavement adjacent to a manhole or catch basin is usually a cave-in that requires reconstruction by the Department of Water Management.  Square or rectangular pavement problems are often failed utility cuts created when contractors dig into the street.  In those cases, CDOT requires contractors to fix the problem at no cost to the taxpayers. Citizens needn’t know the difference to make a 311 report--the issue will be referred to the appropriate department. Regardless of the cause of the pavement problem, the City is committed to fixing the problem as quickly as possible.

Which potholes get fixed first?
CDOT's priority is arterial streets--larger streets that carry the heaviest volumes of traffic.  A repair on an arterial street that carries tens of thousands of vehicles daily will take priority over a residential street that carries far fewer vehicles. However, all potholes are important to us, and every pothole reported to 311 will be fixed.

Does the city do anything to prevent potholes?
Absolutely.  Each year, Chicago paves dozens of miles of arterial and residential streets.  Repaving extends the lifespan of a street many years. In 2023, CDOT resurfaced more than 150 miles of arterial streets, residential streets, and alleyways. This repaving helps us stay ahead of the pothole problem.

Why not use concrete to build streets instead of asphalt?
Three main reasons: cost, installation and maintenance.

Cost: A typical city street is built with a concrete base and an asphalt surface. The lifespan of the base can be extended many years by resurfacing.  Additionally, resurfacing prolongs the life of streets for a significantly lower cost than complete reconstruction.

Installation: Asphalt installation can occur in hours, vs. days for concrete installation, allowing same-day reopening of the street to traffic.  The flexibility of asphalt allows for smooth transitions to the numerous pre-existing fixed points that must be met (curb and gutters, ADA ramps, manholes, existing drainage structures, etc.)

Maintenance: More than 60,000 utility cuts occur annually in order to service underground infrastructure--water, sewer, gas, electrical, etc..  Asphalt accommodates patching more effectively than concrete, and helps maintain a uniform driving surface.  Asphalt provides a quick and effective repair.  Concrete repairs are usually more expensive and time-consuming.

What happens if my vehicle is damaged by a pothole?
The Chicago City Clerk’s Office intakes vehicle damage claims.  Learn more here: https://www.chicityclerk.com/about-mobile-city-hall/claims


To report a pothole, click on the link below.

Service Facts