Costs Of Chronic Urban Flooding Drain Money Out Of Local Economies And Governments


Flooding in Brooklyn, NY | Adam Kuban

Flooding in Brooklyn, NY | © Adam Kuban

It has been raining a ton here in DC over the last few weeks, and torrents of water gushing into storm drains and parked cars standing in flowing water up to their undercarriage has been a common sight on my daily commute. Flooded streets like these are a symptom of the urban flooding that has become a very costly, chronic problem in many urbanized areas throughout the United States.

In fact, the National Flood Insurance Program estimates that it has paid out more than $2.8 billion [PDF] since 1978 to claims related to localized urban flooding. Total insurance claims paid out that were related to urban flooding in Cook County, IL totaled $660 million in just 5 years [PDF]. Up to 25% of economic damages [PDF] caused by flooding occur because runoff overwhelms urban drainage systems, according to FEMA.

For many communities, this type of flooding is a chronic problem. A recent report showed that 70% of survey respondents living in Cook County, IL had flooded 3 or more times in the last 5 years [PDF], and 20% had flooded 10 or more times in that same period. Urban flooding hurts homeowners and small business owners. FEMA estimates that almost 40% of small businesses never reopen their doors after a flooding disaster. Wet basements can decrease property values by 10-25%, not including the indirect costs of flooding to the homeowner such as lost work hours, lost personal mementos, and lost use of a part of their property, at least temporarily.

The good news is that some of these costs could be avoided if we start treating the problem of urban flooding at its source: too many hard surfaces in our cities. These hardened surfaces do not allow the rain to filter into the ground or be slowed down by trees, natural stream channels, and other green spaces. Instead, rainfall hits roads, rooftops, and parking lots where it picks up pollutants before flowing into and flooding our streets and storm drains, ultimately ending up in our rivers and streams.

The EPA is currently working on updating its stormwater programs to address this very issue, working to develop standards to manage rainwater where it falls and incentivizing the use of green roofs, rain gardens, and other types of green infrastructure that can reduce urban flooding. Unfortunately, the EPA keeps missing its deadline.