Yuma Proving Ground (YPG), Yuma, AZ
GCE was awarded a design/build contract for adding a left turn lane and providing roadway improvements for Imperial Dam Road. The purpose of this U.S. Army Corps of Engineers (USACE) project was to alleviate traffic concerns caused by the new visitor center built to serve as a central location to obtain badges for base access, as well as for tourists visiting the Wahner Brook Memorial Site. GCE was provided a basic sketch of the proposed new left turn lane. From the sketch, GCE performed a topographic survey of Imperial Dam Road to utilize as the basis for design. The topographic data identified the existing elevations, existing utilities, edges of existing pavement, existing driveways, current drainage patterns, and existing striping and signage. GCE designed the taper and storage lengths of the turn lane to comply with all Maricopa Association of Governments standards as required by the USACE. The road design also included a 2% cross slope and a drainage ditch to minimize ponding after rain events. The plans included a demolition plan, dimensioned site plan, grading plan, signage and striping plan, and pavement and cross-section details.