When it rains, it pours — and sometimes, in Indy, it floods.

With an exceptionally rainy summer underway, we've already received several flood warnings. Here's why they happen in Indy and how you can stay safe.

Um, why is my basement flooded... again?

Central Indiana used to be composed largely of swamps and marshes. Your own neighborhood may have been a swamp at some point — Broad Ripple used to be known as Bacon's Swamp, while 200 acres of the Old North Side, stretching between Cottage Home and Martindale-Brightwood, was named Fletcher's Swamp. Fun fact: These and other local swamps played a role in harboring escaped slaves as part of the Underground Railroad.

Over time, extensive urbanization and paving have eliminated rainfall absorption areas, i.e. marshes. This means that when it rains, the water has no natural place to go, and ends up flooding our roads and homes as a result.

Pictured is the Washington Street Bridge after the Great Flood of 1913 destroyed it. | Photo via public domain

Has Indy ever experienced any major floods?

In March of 1913, record-breaking rain hit the Midwest, triggering the Great Flood of 1913. This flood affected 13 states, with Ohio seeing the worst damages — but Indiana was not unscathed.

The Washington Street bridge was destroyed, a near west side levee broke and created a 25-ft wall of water that swept across the city, approximately 7,000 Indianapolis families lost their homes, and as many as 200 Hoosiers lost their lives. All told, Indiana's damages were estimated at $25 million, which translates to about $846 million today.

A system of underground tunnels. — The DigIndy tunnel system collects 250+ million gallons of sewage overflow each time it rains. | Photo by WTHR

What's the city doing to alleviate flooding?

The city has a pretty steady wave of stormwater control projects underway at all times. Here are just a few recent ones:

In July 2026, DPW completed a $2 million project to improve the Farley neighborhood's detention basin.
At the end of 2025, the Indiana Department of Environmental Management completed the underground DigIndy tunnel system, a $2 billion project that will keep untreated wastewater from running into our waterways during large storms that previously overwhelmed the infrastructure.
The Marion County Soil and Water Conservation District is currently using $197,000 from a federal grant to plant 50,000 sq ft of rain gardens that will protect Fall Creek from stormwater runoff that carries pollutants into its waters.

How do I stay safe when it floods?

Like any other time it rains in Indy, avoid driving if you can. If you must drive, stick to higher ground, never attempt to drive on a flooded road, and observe all barricades. Just two feet of rushing water can carry cars away.

If you're in the market to move, or have noticed your basement or crawl space getting wet after heavy rainfall, you may want to check if your home or prospective home is located in a floodplain.

If you have questions about flood management or flood insurance, you can contact flood@indy.gov.