Floodplains are defined as areas of land that are subject to being periodically inundated by waters from any source.
The City and County regulate the 100-year floodplain. Floodplains are generally defined by the Special Flood Hazard Area (SFHA) shown on Flood Insurance Rate Maps (FIRMs) which are produced by the Federal Emergency Management Agency (FEMA), by the 100-year floodplain limits shown on Flood Hazard Area Delineation (FHAD) studies and local floodplain maps.
Below are some sources to determine where a property or structure is in relation to the mapped floodplain. Be aware that SEMSWA regulates to the best available data. The best available data may be a study that has not been submitted to or approved by FEMA yet.
Floodplain Status & Lookup Resources (Web Mapping Tools)
The following resources are available to you. Some of them may require a high level of understanding of floodplain regulations and terminology or a familiarity with mapping systems.
- FEMA’s National Flood Hazard Layer (Official) - This is current FEMA floodplain information served by an ArcGIS web map. Addresses and places can easily be searched. Remember to select a “Basemap”.
- Arapahoe County GIS (ArapaMap) - This website allows the user to type in a property address or parcel information in the Arapahoe County area and provides a FEMA delineated floodplain map that includes aerial photography and parcel lines. Once you have opened ArapaMap, select the current floodplain layer in the left window of the screen.
- Urban Drainage EDM - This website allows the user to type in a property address and find studies such as Flood Hazard Area Delineations in the area.
- FEMA Mapping Information Platform - This website allows the user to type in a property address and find the flood hazard information from FEMA's National Flood Hazard Layer. These maps are the most up to date maps that FEMA has, which is not necessarily the best available data.
- FEMA Map Service Center - This website allows the user to type in a property address and find the official FEMA Flood Insurance Rate Maps (FIRMs). These maps are used for official flood insurance determinations. Another data set must be searched to be sure there is not more recent information available.
- Additionally, you may contact SEMSWA's Floodplain Program at 303-858-8844 or use the Contact Us form for lookup services for the best available data and most up to date information. SEMSWA can provide all the floodplain information available for a property or area including FEMA maps, recent changes to FEMA maps, FHADs, unpublished floodplain map data and other recent studies.
If your property is in or near the floodplain. Learn more about the allowed uses in the floodplain. If you are planning a project, determine if your project is ALLOWED in the floodplain and what the requirements are for working in the floodplain.