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Energy Corridor - Residual Elevation and Flood Risk
- 1. BP Westlake Complex Shell Woodcreek Complex ConocoPhillips Main Campus Energy Center Complex Residual Elevation Surface West Houston I-10 / Energy Corridor – 1:10,000 Zoom (World Street Map, Terrain Residual, Multi-Directional Hillshade) Constructed by D Tolman, dntolman@gmail.com Relative Elevation High Low I-10 Buffalo Bayou Turkey Creek Langham Creek
- 2. BP Westlake Complex Shell Woodcreek Complex ConocoPhillips Main Campus Energy Center Complex Residual Elevation Surface & FEMA West Houston I-10 / Energy Corridor – 1:10,000 Zoom (World Street Map, Terrain Residual, Multi-Directional Hillshade) Constructed by D Tolman, dntolman@gmail.com Relative Elevation High Low I-10 FEMA Floodway FEMA 500 yr Floodplain FEMA 100 yr Floodplain
- 3. Discussion: • The first image is an enlargement of the Energy Corridor showing three layers: World Street Map, Multi-Directional Hillshade and the Residual Map of the LIDAR Elevation Surface. The colors clearly show the relative elevation highs and lows in the Energy Corridor area. The second image shows the FEMA flood designations superimposed on the map. I believe that the two are in close agreement, particularly along the drainage systems. • There are differences however, likely due to FEMA’s focus on localized flooding along streams and channels. Alternatively, the residual map shows all local low areas, even those not adjacent to streams. I have noted that many of the structures that flooded during the two major flood events of 2016 were not within a FEMA designated flood zone. I suggest that, due to the very low surface gradients in the area, water from extreme rainfall events will temporarily “pool” with local low areas, and cause short-lived flooding outside of FEMA designated areas. • These extreme rainfall events seem to be more and more common, in which case every foot of elevation matters. Perhaps an increased awareness of this topic would allow the public to make more informed decisions regarding flood insurance.