Figure 3 - Proposed Typical Section of SR

SR 70 TYPICAL SECTION

b. Cross Drain Design Considerations

Table 1 provides the required storm events to be analyzed for each cross drain, per the FDOT Drainage Manual and Culvert Handbook requirements.

Table 1 – Storm Frequency Criteria

Storm Event FrequencyReason
10-yearGeneral Roadside Ditch Culverts
25-yearDesign Flood Event (20-year project of AADT < 1,500)
50-year*Design Flood Event (20-year projection of AADT > 1,500)
100-yearBase Flood Event
500-yearGreatest Flood Event

* This is the design storm for this project.

Per the FDOT Drainage Manual, the rainfall depths utilized for the modeling were based on the NOAA Atlas 14 Point Precipitation Frequency Estimates at Arcadia, Florida. For the purposes of the location hydraulic analysis, only the 24-hour duration was reviewed.

SR 72 from CR 661 to SR 70 & SR 70 from CR 661 to the Peace River Bridge FM #: 443123-1-22-01

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