Tierra completed a cultural resources inventory for the Franklin County Public Works Department’s replacement of a structurally deficient timber bridge with a steel multi-plate arch structure. The Washington State Department of Transportation Local Programs Division assisted the County and acted on behalf of the Federal Highway Administration in processing Federal environmental compliance documentation. Tierra’s assessment consisted of archival research, archaeological fieldwork, built environment survey, and preparation of a technical report detailing the results of the work. The Hollingsworth Road Bridge was recommended Not Eligible for listing in the National Register of Historic Places (NRHP); however, the Wahluke Branch 10 Lateral Canal (over which the bridge spans) was recommended Eligible for the NRHP as a contributing resource in a potential Columbia Basin Project historic district. Tierra concluded that the bridge replacement work would have minimal impact on the integrity of the canal and not constitute an adverse effect.