This Permanent Restoration project is located along State Route (SR) 299 from postmiles (PM) R8.7 to R9.2 and R11.1 to R11.4. The project proposes to stabilize two failing slopes via retaining structures. During a federally declared storm event, a portion of the roadway prism at each location experienced significant movement, resulting in the need for restoration and permanent stabilization.
The proposed work at Location 1 (PM R8.7 to R9.2) will include slope repair and stabilization via removal of existing earth retaining elements (e.g. gabion baskets, concrete wall, ground anchors, etc.) and installation of a soldier pile ground anchor (SPGA) wall. In addition, the eastbound shoulder will be widened to 10-feet along the SPGA wall, two culverts will be replaced (at PM R8.8 and PM R11.3), and existing guardrail will be upgraded to Midwest Guardrail System (MGS).
The proposed work at Location 2 (PM R11.1 to R11.4) will include slope repair and stabilization via installation of a SPGA wall and replacement of a culvert at the north end of the wall. In addition, the eastbound shoulder will be widened to 10-feet along the SPGA wall and MGS will be installed along the top of the wall (see project layouts and typical cross sections). The work proposed by this project will decrease the risk of further movement of the roadway due to failure of the slopes supporting the roadway prism.