The Las Deltas Safe Drinking Water Project proposes to replace about 10 miles of existing pipeline and replace aging storage tanks in the community of Las Deltas, an unincorporated community in the City of Firebaugh, Fresno County. The project is being funded by the Safe Drinking Water State Revolving Fund, which is administered by the State Water Resources Control Board and is partially financed by the U.S. EPA. Cultural resources studies for the project were completed by Horizon in partial fulfillment of CEQA requirements and in compliance with Section 106 of the National Historic Preservation Act.

Horizon archaeologists conducted a record search for the project, coordinated with tribes identified by the Native American Heritage Commission, and conducted a field study that involved survey of the approximately 10 miles of pipeline alignment within or adjacent to established roads, and survey of two storage tank locations. Two isolated prehistoric artifacts were identified during the field study. Due to their limited data potential, isolated artifacts are not considered eligible for the California Register of Historical Resources (CRHR) or National Register of Historic Places (NRHP). Because the replacement pipeline will be affixed to the Delta-Mendota Bridge in the same manner in which it is currently attached, it was determined that the project will have no effect on historical resources under CEQA or historic properties pursuant to 36 Code of Federal Regulations 800.4(d)(1).