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  • Floodplain Map
  • Creeks of Boulder
  • Floodplain Development
  • Be Prepared
  • Community Resilience

Prepare for Floods

 « Return to Flood Info

Floods can happen at any time in Boulder with little or no warning.

Be prepared - you may only have minutes to react.

The City of Boulder is the No. 1 Flash Flood Risk community in the state of Colorado. Are you prepared? The City of Boulder participates in the National Flood Insurance Program (NFIP) by adopting and enforcing floodplain management ordinances to reduce future flood damage. In exchange, the NFIP makes federal government-backed flood insurance available to homeowners, renters and business owners, whether or not their properties are in a floodplain. 

The city also participates in the Community Rating System The NFIP’s Community Rating System (CRS) is a voluntary incentive program that recognizes and encourages community floodplain management activities that exceed the minimum NFIP requirements. Flood insurance premium rates are discounted to reflect the reduced flood risk resulting from community actions that meet the three goals of the CRS:

  1. Reduce flood losses;
  2. Facilitate accurate insurance rating; and
  3. Promote the awareness of flood insurance.

For CRS participating communities, flood insurance premium rates are discounted in increments of five percent: i.e., a Class 9 community would receive a 5 percent premium discount, while a Class 8 community would receive a 10 percent discount. The city joined the CRS in 1992 as a Class 8 community, improved to a Class 7 in 2008 and then to a Class 6 in 2012. The city was awarded a Class 5 rating in early 2013. As a result, standard policyholders now receive a 25 percent discount on flood insurance with anticipated citywide annual savings of more than half a million dollars.  

Flood Watches and Warnings

Flash Flood Watch  - Weather conditions may cause flash flooding in the specified area. Be ready to move to higher ground during heavy rainfall.

Flash Flood Warning  - Flash flooding is occurring or is imminent in the specified area. Move to higher ground immediately. In some locations and situations, it may be safest to shelter in place on the upper floor of the building.

Related Videos

  • Disconnect electricity and gas
  • Do NOT walk or drive through flood waters
  • Get to higher ground
  • Follow emergency response orders

Floods of any size can be devistating. Before you plan any post-flood repair, make sure to check if you need any permits prior to starting your repairs. 


A City of Boulder permit and inspection is required for projects that affect the structure of a building or its electrical, mechanical, or plumbing systems.

Before beginning any flood-related projects for your property, contact P&DS to determine if a City of Boulder permit is required. Email [email protected], visit or go to the Planning and Development Services Center.

Any modifications or improvements to protect private property must not adversely impact adjacent properties and must comply with all adopted building codes, design and construction standards, and land use regulations.

Floodplain Development

Specific Floodplain Development requirements may be applicable for properties located in the floodplain. Property owners with buildings located in the 100-year floodplain are required to obtain a Floodplain Development Permit pdf before expanding a building or constructing improvements.


Qualified maintenance staff or professional contractors licensed with the City of Boulder must complete many of the projects that require a city permit. Visit the Hiring a Contractor page for lists of city-licensed professionals.


Additional Resources

View these helpful resources to learn more about flood safety and personal preparedness:

View these helpful resources to learn more about flood emergency plans:

Take protective measures now to help reduce property damage during future floods.

Flood Insurance

Most standard homeowner's insurance policies do not cover flood damage. Property owners may purchase flood insurance coverage for building structures, contents insurance for personal possessions, and additional insurance coverage for sewer backups. Boulder residents and businesses are eligible for up to a 25 percent discount on standard flood insurance rates.

Sewer Backup Prevention

Learn more about how to prevent sewer backups in your building.

The sanitary sewer service line is the responsibility of the property owner, up to and including the connection to the city-owned sewer line. Property owners should consult with a professional plumber to investigate and resolve problems determined to be in the sewer service line.