Council hears citywide stormwater assessment with $1.7M East Rock Spring project among priorities

Gradient Engineering presented the City of Henderson with a planning‑level stormwater infrastructure assessment and a hydrologic/hydraulic model intended to guide prioritized repairs and future capital projects.

Consultant Alex Nice told the City Council the model covers roughly 16,000 acres across the city’s main drainage areas — Redbud, Sandy, Ruin and Nutbush creeks — and was calibrated using six qualifying rain events from January through July 2025. He said the team completed 216 inspections of city‑owned assets and used aerial imagery, mobile field tools, 360‑degree cameras and selective CCTV to gather data.

The consultants combined condition scores and a Business Risk Exposure (BRE) metric (1–25) to identify priorities. Most assets fell into the low‑risk category, the presentation said, but pipes and some manholes showed higher levels of deterioration that warrant attention.

Using the model and condition assessments, staff and consultants identified 13 preliminary projects and provided planning‑level cost estimates. Notable projects and estimates included East Rock Spring Street (replace failing corrugated metal pipe with reinforced concrete pipe; about $1.7 million), Woodland Road (culvert replacement; about $615,000), Coble Boulevard (replace a deteriorated 60‑inch pipe; about $237,000), a combined package addressing John Street, Hamilton Street and Whitten Avenue (about $652,000), Owen Street and Booth Street (about $496,000), and five failing inlets across the city (Oak, Cedar, Granite, Ridge and Park avenues; combined estimated $282,000).

City staff noted the assessment covered only city‑owned infrastructure (assets over 12 inches that can be assessed from above ground) and excluded North Carolina Department of Transportation and private systems. Councilmember Tami Walker asked about the inventory’s completeness; project consultant Sujit Ekka said the inventory is approximately 90 percent complete with ongoing corrections and additions.

Councilmember Geraldine Champion inquired about flooding at the entrance to a Food Lion parking lot and how the City would differentiate responsibility for NCDOT versus city assets; Mr. Nice reiterated that the current assessment excluded NCDOT assets and said further work would be needed to assign responsibility in mixed‑ownership locations.

The draft report remains under staff review, and consultants said they can provide more detailed project descriptions on request. Councilmembers and staff indicated the assessment will help prioritize projects for safety and for potential funding applications.

Next steps noted in the presentation include refining project scopes, confirming ownership and responsibilities for problem locations, and pursuing funding opportunities for high‑priority projects.