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September 2013 Flood

Rainfall-Runoff Analysis for the September 2013 Flood in the City of Boulder pdf

1,000-year Rainfall
More than 18 inches of rain fell in Boulder from Sept. 8 to 16, 2013, a storm with a 0.1 percent chance of occurring in any given year.

Significant Flooding
This unprecedented rainfall caused 25- to 100-year flooding along Boulder's 15 drainageways, but no 1,000-year flooding.

Not a 1,000-year Flood
The rain fell over several days and resulted in peak flow rates more consistent with shorter-duration storms that have a much higher likelihood of occurring in any given year.

Summary Report of Private Property and Resident Flood Impact Survey and Analysis pdf

After the September 2013 flood, the city surveyed property owners and residents to assess the private property damage caused by the flood.

♦  Cause of Damage - Major creek flooding, groundwater infiltration, local drainage flooding, floor drains, and/or wastewater backup.

♦  Property Type - Dwelling, business, or other property.

♦  Cost Breakdown - For each category and drainage basin.

♦  Comparison - Reported out-of-pocket damage costs versus the amount paid out by FEMA.

Boulder Flood Infographic pdf

Boulder Flood: One Year Later

September 2013 Flood Maps

Maps of the September 2013 flooding and associated impacts to people, private property and public infrastructure in the City of Boulder.

This mapping is not used for regulatory purposes and does not change the FEMA floodplains. This information was captured to document the event and provide insight to guide future analysis and mitigation.

Boulder Flood Photos

September 2013 Flood

From Sept. 11 through 15, 2013, the Front Range region experienced unprecedented rainfall, causing significant flooding, loss of life, and widespread damage. As a result of the flooding, Boulder County (including the City of Boulder) has been designated a Federal Disaster Area.

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