Costello Inc. Lowers Premiums for Flood Insurance by Clarifying Actual Flood Levels
A recent update to the FEMA Flood Maps in Fort Bend County, TX resulted in significant increases in the 100 year flood levels near the City of Richmond. The updated FIRM resulted in undesirable increases in the required flood insurance rates for a planned development adjacent to the Brazos River.
Costello Inc. (CI) was hired by Planned Community Developments to work with the Fort Bend Drainage District to see if an alternative assessment of the 100 year floodplain was feasible. After reviewing the original HEC-RAS model used to obtain the revised floodplain map, it was clear that the assumptions and limitations of a one-dimensional (HEC-RAS) model were causing the 100 year floodplain elevations to be over-predicted.
CI successfully applied a two-dimensional modeling approach using DHI's FEMA approved MIKE FLOOD modeling software to produce a more realistic representation of the overbank flow and surface drainage during the 100 year flooding scenario. The use of 2D modeling for this project had significant economic and social impacts including:
- More realistic flood maps
- Lower flood insurance premiums
- Lower cost of flood mitigation measures