Based on the Flood Insurance Rate Maps (FIRM), Florida Floodzone Services is clustering neighborhoods together based on the FEMA flood zone boundaries to create a Flood Analysis Zone (FAZ).  These boundary limits are usually based on roadways and waterways determining the flow and direction of the floodwaters.  With an established FAZ area, our company creates a summary of  the FAZ area including: FEMA designated flood zone and elevation, type of flooding sources, number of affected structures,  insurance premium cost, local sources of mapping data.

Florida Floodzone Services field personnel consist of Florida licensed Professional Surveyors and Mappers.  Our team establishes a vertical control network, throughout the analysis zone using the National Geodetic Survey standards for a third order survey.  This network consists of establishing an elevation on a zone analysis control point every 400 feet along or near the centerline of the existing roadways.  This network is also derived from published governmental benchmarks having a known elevation.  To determine higher accuracy levels, our field procedures require 5 or more of these benchmarks.  These analysis points are used for individual structure evaluations for flood zone removal and/or flood insurance reduction services in this neighborhood.

Using aerial and satellite vertical data, our research division is simulating flooding models within these Flood Analysis Zones.  The first part of this phase is to correct and adjust the vertical data to the established vertical control network.  The original format of the aerial data has a error tolerance of 0.5 to 1.0 feet and can be adjusted in a localized area to 0.2'+/- error range.  Field inspections after a heavy rainfall has verified the absolute low areas in neighborhoods, as reflected in the flood simulations.  The second part of this phase is producing a series of flood maps for the overall analysis zone.

              Flood Level at 3.0 NGVD 1929           Flood Level at 3.5 NGVD 1929

               Flood Level at 4.0 NGVD 1929           Flood Level at 4.5 NGVD 1929

               Flood Level at 5.0 NGVD 1929            Flood Level at 5.5 NGVD 1929

               Flood Level at 6.0 NGVD 1929           Flood Level at 6.5 NGVD 1929

Using the flood simulation maps Florida Floodzone Services is overlaying the FEMA flood zone boundaries from the Flood Insurance Maps (FIRM).  In most cases it has been determined that the calculated/published floodzones are located correctly on the FIRM.

The flood simulation maps are also used to determine the high areas of the neighborhood.  Structures within these high areas should be candidates for obtaining an exempt status from the FEMA floodzone.

                    

 New - AE (elev 5.0 NAVD 88) flood zone                  Prior AE (Elev 6 NGVD 29) flood zone

A detail review of the comparison of the old and new flood zones for this area has determined that the Base flood elevation has increase one half of a foot.  This increase is probably due to the new maps being rounded up to the nearest whole number.   A review of all the Broward County has discovered this rounding issues on almost every panel.

This neighborhood was build on average at the elevation of 6.0' NGVD 29 = 4.5' NAVD 88. Houses with a floor elevation of 6.0' (4.5) or more the insurance rates will remain the same, but homes with a slightly lower floor elevation the insurance will double to $2,792 (pre-FIRM) or $5,380 (post-FIRM) at $1,526. Insurance estimates are based on maximum coverage amounts.

We have determined that the new flood maps could cause the homeowners remaining in the flood zone will probably expect insurance increases.   In AH / AO flood zones with this  the increase will be from $405 to $1,328, becuase the house is not incompliance to the new flood zone.  In AE flood zone areas the increase will be from $1,526 to $5,380 (Post-FIRM) or $2,792 (Pre-FIRM).  In the VE Flood zone are the insurance increase will be a $5,000 to $15,000 increase, depending on the building type. (high rise buildings the insurance increases could br in the $100,000 range.