One Build Alternative was developed for this PD&E Project. The Build Alternative proposes raising the profile of SR 72 and SR 70. A dry retention pond (wide swale) is proposed north of SR 70 between the roundabout and the Peace River relief bridge to provide stormwater management for SR 72 and portions of SR 70. Drainage for the SR 70 portion east of the bridge will remain existing open roadside ditches and existing inlets at the bridges. SR 70 runoff flowing to the north side of SR 70 will be conveyed to the pond via open swale, inlets, and pipes. The remainder of SR 70 will follow existing drainage patterns. Offsite water will utilize existing cross-drains and will bypass the proposed treatment swale.
Another improvement that was adopted from previous traffic studies was introducing a roundabout at the intersection of SR 72 and SR 70. This improvement addresses the safety needs of the project by reducing the overall severity of crashes as well as the overall number of crashes as compared to the current stop control. The roundabout design requires realigning the SR 72 alignment to the west in order to avoid the existing transmission pole.
As shown in Figure 2 & Figure 3, the main typical section for both SR 72 and SR 70 consists of two 12-foot lanes with 10-foot shoulders (5-foot paved) with various configurations of roadside ditches for the conveyance of runoff. The right-of-way varies from 200' to 250'.
Figure 2 – Proposed Typical Section of SR 72
SR 72 TYPICAL SECTION
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