The city has challenged a 100-year floodplain map prepared by the Federal Emergency Management Agency that adversely affects Canyon Acres property owners.
FEMA's map is based on aerial photographs of areas that generate enough run-off to create a problem in a flood. City officials claim the map relied on outdated information and have submitted a hydrology study to make their case.
"The map was done on an extremely broad-brushed level," said City Engineer Steve May, director of the Public Works Department.
FEMA's new map increased the number of homes in Canyon Acres that are within its mapped 100-year floodplain. Letters have been sent to 37 property owners, as required by the agency.
Owners of Canyon Acres properties clustered in the FEMA-mapped floodplain are required to buy expensive flood insurance and are subject to development restrictions, which could also affect their neighbors, city officials said.
However, FEMA's map does not take into consideration the city's Canyon Acres drain installation, and the city has resubmitted a study authorized by the council in March showing the hydrology of the area since the installation in 2008.
"If the study is approved by FEMA, then all the homes in Canyon Acres could be removed from [its] mapped 100-year floodplain," City Manager John Pietig said.
The council authorized the $26,000 engineering study recommended by May in March. Harris & Associates, the engineering firm that prepared the original hydrology and hydraulic analysis for the Canyon Acres storm drain, prepared the study.
Public Works funds paid for the preparation of the hydraulic calculations and documentation for the Canyon Acres Floodplain Insurance Rate Maps.