Purpose and Scope
Communities within the Tar-Pamlico River Basin, North Carolina have a long history of flooding during major rainfall and hurricane events. Many communities within the basin have experienced major recurring flood events over the past 25 years associated with Hurricanes Fran (1996), Floyd (1999), Matthew (2016)—each of which ranking among the most destructive storms in state history and representing among the top four floods of record for major population centers within the basin. Recurring flooding within the basin results in economic damages to homes, businesses, industry, and public infrastructure. Inundation of structures and roadways (i.e., reduced access to critical services and recovery aid, inundation of occupied vehicles) also results in increased life safety risks both during and following flood events.
In response to recent flooding that occurred as a result of Hurricanes Matthew (2016) and Florence (2019), the U.S. Army Corps of Engineers received funding through the 2019 Additional Supplemental Appropriations for Disaster Relief (H.R. 2157) for a feasibility study to assess and recommend actions that reduce flood risk and increase resiliency within the Tar-Pamlico River Basin. A series of flood risk management alternatives designed to reduce flood risks within the basin through various combinations of structural (e.g., floodwalls, levees, detention basins), non-structural (e.g., acquisition and relocation, home elevation), and natural and nature-based measures (e.g., wetland and floodplain storage) were developed and compared with the goal of identifying and recommending an alternative that reduces flood risk while protecting environmental resources.
Study Area
The study area is located within the Tar River Basin, North Carolina. The Tar River Basin begins in the piedmont of North Carolina and extends 215 miles southeast through the Coastal Plan and flows to the Pamlico Sound estuary. The basin covers about 6,100 square miles. The study area is comprised of river reaches located along the Tar River and its major tributaries. Major population centers within the study area include Louisburg, Rocky Mount, Greenville, Tarboro, and Princeville, NC. The Pamlico River, including the City of Washington, NC was excluded from the current feasibility study and is being recommended for a subsequent study that would focus on characterizing and evaluating solutions to address combined riverine and coastal flooding.
Study Update
The study team has finalized the development, evaluation, and comparison of potential alternative flood risk management plans and has identified a draft recommended plan—also called the tentatively selected plan (TSP)—for reducing flood risk within the study area. All analyses have been included in a draft report.
2023 Draft Integrated Feasibility Report and Environmental Assessment and Public Meeting
Summary
The Pittsburgh District has prepared the draft Integrated Feasibility Report and Environmental Assessment (IFR/EA) for the Tar Pamlico River Basin Flood Risk Management Study, dated October 2023. In addition to publishing the draft, the district hosted a comment opportunity wherein public comments about the draft will be collected and considered. The comment period closed on Friday, Dec. 1.
The draft IFR/EA addresses the development, evaluation, and comparison of alternative flood risk-management plans and describes the draft recommendation—or tentatively selected plan—for federal action to reduce flood risk and damages along the Tar River and its tributaries. The tentatively selected plan for the Tar Pamlico River Basin Flood Risk Management Study includes applying nonstructural-flood risk-reduction measures—or measures applied to a structure and/or its contents that prevent or reduce the damage from flooding—to 157 structures including:
- Structure elevation and/or flood venting – 61 structures
- Dry floodproofing – 96 structures
Only habitable structures would be eligible for inclusion in the nonstructural recommendation. The tentatively-selected plan includes elevating 2 structures, elevating and flood venting 7 structures, flood venting 4 structures, and dry floodproofing 22 structures along Stony Creek in the vicinity of Nashville and Rocky Mount, NC; elevating 1 structure, elevating and flood venting 5 structures, flood venting 4 structures, and dry floodproofing 10 structures along the main stem of the Tar River in the vicinity of Rocky Mount, NC; elevating and flood venting 1 structure and dry floodproofing 9 structures in in the vicinity of Tarboro, NC; and elevating 32 structures, elevating and flood venting 5 structures, and dry floodproofing 54 structures in the vicinity of Greenville, NC.
Structure elevation raises a house or building so that the lowest floor is above the 1% annual exceedance probability event (i.e., an event with a 1% change of occurring in any given year or that occurs on average once every 100 years) plus two feet. Flood vents protect houses and buildings during floods by preventing hydrostatic pressure buildup that can destroy walls and foundations. Structure elevation and flood venting can be used independently or in combination with one another, depending on the individual structure characteristics. Dry floodproofing involves sealing building walls and openings to prevent the entry of flood waters and is most applicable in areas of shallow, low-velocity flooding. Structures are dry floodproofed to the 1% annual exceedance probability event plus two feet, or a maximum height of four feet. Dry floodproofing is only applicable to non-residential structures.
The draft IFR/EA has been prepared in accordance with the Council on Environmental Quality and Corps of Engineers requirements for implementing the National Environmental Policy Act (NEPA) of 1969 (33 CFR 230), as amended, and addresses the relationship of the proposed action to other applicable federal and state laws and executive orders. The draft report addresses the impacts of the tentatively selected plan on environmental resources, including, but not limited to federally listed threatened and endangered species, archaeological and historical resources, wetlands, fish and wildlife habitat, soils, and water and air quality. This public notice is being distributed to notify all known interested persons of the availability of the draft IFR/EA for review. A Finding of No Significant Impact (FONSI) pursuant to NEPA would be completed by the corps if comments received during the review period indicate that a FONSI is appropriate.