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To provide construction access to a dam site at a utility in the southeastern United States of America, a temporary access bridge was required to span a river to enable access for large earthwork equipment and concrete trucks. A timber piled load transfer platform (LTP) and geosynthetic reinforced soil (GRS) abutment with mechanically stabilized earth (MSE) approach embankment was designed for the left bank. Excavation of up to 3 m of very soft soils and backfilling with cyclopean concrete was performed for the GRS abutment on the right bank. The grid of timber piles was driven through alluvium up to 11 m in thickness, comprising very soft to soft clay, silt, and interbeds of silty sand. The cyclopean concrete for the ground improvement of the right abutment comprised rip rap boulders embedded in flowable fill. A modular steel panel bridge, of the “Bailey type,” was erected and lifted into place on the abutments. The bridge and its abutments were designed to carry fully loaded CAT 745 articulated dump trucks over the 45.7 m single span bridge. Subsurface exploration was performed with SPT borings and geotechnical index testing. Global stability of the left abutment was governed by undrained shear deformation in the clay (design value Su 28 kN/m2), and it was for this condition that a piled LTP was selected. A program of pre-production piling was performed, with high-strain dynamic testing using a pile driving analyzer to verify driving criteria. To mitigate risks to the abutments during flood events, the backfill was selected as a free draining coarse aggregate, and the walls were armored with rip rap. Results of the test piling and production piling are presented, illustrating the challenge of designing temporary works in a highly variable alluvial ground profile. During the six-month period of mass earthwork, approximately 170,000 m3 of earth was moved across the bridge in an estimated 8,000 truck movements (heaped), and the same number of crossings for the returning trucks (empty). The bridge and abutments performed without adverse deformation under these service loads. A severe flood occurred during construction, and the abutments performed as intended without damage. Constructability lessons learned are discussed, including clearance requirements for crane outrigger pads. The integration of a timber piled LTP with a free draining GRS abutment provided stability during rapid construction loading, and flood resilience and reliability during the mass earthwork phase of the project.