Background
The 2013 flood event caused widespread damage along waterways throughout Boulder County and other areas of the state. In response, the State of Colorado took steps to bolster long-term planning and resiliency efforts by funding CHAMP, managed by the Colorado Water Conservation Board (“CWCB”). CHAMP is updating local hazard information, including producing new regulatory floodplain maps for the most affected waterways. Boulder County has already incorporated draft CHAMP data into its Regulatory Floodplain Maps via BOCC Resolutions 2017-68 and 2018-78.
In September/October 2019, FEMA will release preliminary Flood Insurance Rate Maps (Preliminary FIRMs) based on the CWCB/CHAMP remapping efforts. The Preliminary FIRMs are expected to have several, but generally small differences from the already adopted draft CHAMP maps, largely due to clean-up and smoothing of boundaries. The Preliminary FIRMs are also likely to be very similar to the future effective final FIRMs; however, the final FIRMs are unlikely to be ready for another two years. Local adoption of the Preliminary FIRMs, as compared to waiting two or more years for release of the final FIRMs, will accelerate the ability for staff and residents to rely on floodplain risk mapping and associated zoning that will be most similar to the county’s and FEMA’s final floodplain mapping.
In addition to the CHAMP remapping process, FEMA periodically conducts new floodplain studies through its Risk Mapping, Assessment, and Planning (Risk MAP) process. One such study on Coal Creek and Rock Creek resulted in a recent (August 15, 2019) update to the FIRM and reflects many topographical and drainage changes from the previously effective flood studies conducted in the 1980s. The FIRM update was automatically incorporated into the Floodplain Overlay (FO) District, as required by section 4-403.A.1 of the Land Use Code. The Boulder County floodway in this reach is now superseded and should be considered for removal from the FO District.
On September 19, 2019, staff received BOCC authorization to analyze possible comprehensive zoning map amendments for the FO District, specifically the local Boulder County Floodplain and Floodway, based upon the CHAMP Preliminary FIRMs, as well as FEMA Risk MAP final FIRMs and other best available data. Staff has received authorization to pursue these possible zoning map amendments because the amended maps will align the Boulder County Floodplain with FEMA flood hazard zones and allow staff to more effectively and efficiently incorporate best available data into our regulatory scheme, thereby enabling county staff to better protect the health, safety, and welfare of the residents of and visitors to Boulder County.
These floodplain zoning map amendments will be accomplished through the process set forth in the floodplain regulations in the Code and include technical review, public notification, and hearings before the Planning Commission and Board of County Commissioners. Residents will have an opportunity to be part of the process through this zoning map amendment and to have certainty about the regulations and associated mapping that affects property in the county.