The roadway profile will be increased. As identified in the existing conditions modeling, the current roadway profile of SR 72 is insufficient for being usable during an emergency event. As a result, the roadway profile is proposed to be higher than the recorded stages from the modeling.
For the proposed PD&E model, the existing conditions model was updated to remove the overtopping weirs over the SR 72 roadway (i.e. flow condition was set to none). The cross-drain size for CD-1 was enlarged to an 8'x 8' concrete box culvert for resiliency to add flow capacity during extreme storm events that prevents the roadway from overtopping. The increased culvert size would also provide wildlife connectivity below the roadway. CD-2 was upsized from a single 30-inch cross drain to a double 30-inch cross drain. This sizing maintained the wetland stage upstream (Node 302) with no roadway overtopping. EX-3 was removed from the model (i.e. flow condition was set to none) as this runoff will be conveyed to CD-2 in the proposed condition within the proposed right-of-way and discharge from the right-of-way at the same location as in the existing condition. Table 3 shows a summary of the existing and proposed cross drains for the design storms and Table 4 shows the flows through the simulated hurricanes in the existing and proposed conditions.
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