South Hillsboro Reservoir Siting Geotechnical & Environmental Investigations

RH2 conducted geologic and environmental investigations to support the City of Hillsboro’s evaluation of a preferred site for the future South Hillsboro Reservoir. Geotechnical work included test pits and borings to depths of up to 75 feet, along with laboratory testing of representative soil samples to evaluate subsurface conditions, foundation feasibility, excavation considerations, and stormwater management. Findings were documented in a technical memorandum that integrated field data with prior screening-level studies to provide a clear understanding of site conditions.

In parallel, RH2 completed a Phase I Environmental Site Assessment to identify potential environmental constraints affecting site acquisition. The assessment included regulatory and historical record reviews, property research, site reconnaissance, and coordination with the property owner. The results confirmed the absence of recognized environmental conditions and supported the City’s decision-making for future reservoir development.