Dupont Wappoo Watershed Improvements Plan

The City of Charleston is soliciting an engineering firm to provide Phase One conceptual design and planning services for the Dupont Wappoo Watershed Improvements Project, a 1,600‑acre flood‑mitigation effort in West Ashley. The consultant will develop existing‑conditions assessments, hydrologic/hydraulic models, evaluate improvement alternatives, coordinate regulatory permitting, estimate costs, and produce a Phase One Design Package for handoff to the U.S. Army Corps of Engineers. The scope is limited to conceptual engineering; detailed design, permitting, and construction documents are reserved for Phase Two. • Develop preliminary site assessments, limited topographic survey, and field investigations. • Perform conceptual hydrologic & hydraulic modeling (StormWise) and evaluate flood‑reduction alternatives. • Review regulatory, permitting, property, easement, and environmental constraints; begin coordination with USACE, FEMA, SCDES, SCDOT, etc. • Produce cost‑estimate ranges, phasing recommendations, and a comprehensive Phase One Design Package (reports, models, GIS/CAD files, exhibits). • Participate in a handoff meeting with City and USACE; conduct bi‑weekly progress meetings and public outreach. • Must meet City Small Business Enterprise (SBE) goals; submission deadline 10 Sept 2026 – 9 Oct 2026.