Tusayan moves forward with flood plain remapping for Ten X development site
TUSAYAN, Ariz. — After relinquishing floodplain management responsibilities and reaching an agreement with Coconino County regarding unpermitted work at the Ten X housing development site, Tusayan is ready to move forward with remapping the area’s designation by the Federal Emergency Management Agency (FEMA).
At the July 10 meeting, the Tusayan Town Council voted unanimously to request its engineering firm, Woodson Engineering, prepare and submit an application to FEMA that would make newly-obtained data available to FEMA for review and revision of the project site’s floodplain designation. The update would apply only to the Ten X site, with the designation for the rest of the town to be potentially reviewed at a later date.
Results from the town’s aerial LIDAR study, completed earlier this year, indicate the flow rate through the Ten X development site is about 2,100 cubic feet per second (cfs).
Tusayan Councilmember Robb Baldosky said in order for the data provided by the town to become effective, the town’s engineering firm needs to submit an application for a Conditional Letter of Map Revision (CLOMR). This would be the first step to resuming construction on the development. While a building permit cannot be granted based on a CLOMR, it is the first step in the process to revise the National Flood Insurance Program (NFIP) map. The CLOMR indicates whether the project — in this case, the Ten X housing development — if constructed as proposed is consistent with the requirements of the NFIP. After reviewing calculations, FEMA will issue a letter with a determination of compliance. This determination will establish whether or not a local floodplain permit may be issued after review by the Coconino County Flood Control District.
Baldosky said the CLOMR process could take up to 18 months to complete and could cost up to $30,000. Once the town receives a CLOMR and a building permit, construction of the housing development can be completed. The town can then apply for a Letter of Map Revision (LOMR) based on the actual build of the project. The LOMR constitutes an official floodplain map revision.
Mayor Craig Sanderson said the town had provided new data from an aerial LIDAR study to replace data last gathered in the late 1960s.
“Using the best technology gave us good data as opposed to the broad brush of where the floodplain is,” he said. “It not only gave us information on Ten X but assisted us … the town of Tusayan on where the floodplain is.”
That new data is important, Baldosky said, because the best available data is the standard by which every other project and flood insurance rates in town will be measured.
“Once we do this at Ten X, it becomes the calculator, the best available data for the entire town,” he said. “If this is approved, it’s substantially less than what was just assumed to be the numbers to use. This is a very valuable asset to the rest of the landowners because now that data is there.”