C UMULATIVE I MPACTS

The Council on Environmental Quality (CEQ) regulations (40 CFR parts 1500-1508) for implementing the National Environmental Policy Act (NEPA) requires an assessment of the effects of a proposed action on the environment. Those effects are to include the following components:

“… ecological (such as the effects on natural resources and on the components, structures, and functioning of affected ecosystems), aesthetic, historic, cultural, economic, social, or health, whether direct, indirect, or cumulative. Effects may also include those resulting from actions which may have both beneficial and detrimental effects, even if on balance the agency believes that the effect will be beneficial.”

According to the CEQ, a cumulative effect:

“…is the impact on the environment which results from the incremental impact of the action when added to other past, present, and reasonably foreseeable future actions regardless of what agency (Federal or non-Federal) or person undertakes such other actions. Cumulative impacts can result from individually minor but collectively significant actions taking place over a period of time.”

An assessment of cumulative effects helps one identify the significance of an impact. The assessment sets the stage for determining the importance of the incremental effect produced by a proposed action. When considering significance, one should examine whether the action is related to other actions with individually insignificant, but cumulatively significant impacts. The CEQ regulations state that “significance exists if it is reasonable to anticipate a cumulatively significant impact on the environment”.

An analysis of cumulative effects does not need to be performed on every natural resource in the project area or potential avenue of environmental impact. Such an analysis is warranted only for those resources or issues that are likely to be affected by the proposed alternatives in a substantial manner.

8.14.1 IDENTIFICATION OF SIGNIFICANT RESOURCES

The State and Federal Agencies within the Princeville PDT reviewed a list of potential means by which the Princeville Flood Risk Project could adversely affect the human environment and agreed that the following were the major resources or issues of concern for this project:

• Wetlands

• Wildlife Habitat

• 1% Chance Event Floodplain

• Increased adjacent and downstream flooding

• Farmlands (i.e., Prime Farmland Soils)

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• Endangered and Threatened Species

• Cultural / Historic

• Tar River Riparian Buffer Area

• Socio-economic 8.14.2 PAST ACTIONS

Since the late 19^th century, the USACE has worked to reduce flood impacts by removing snags and other debris from the river channel and has protected the Towns of Princeville and Speed by constructing flood control levees. According to the USACE, Wilmington District, Project Maps FY-90, dated 30 September 1990, the following USACE projects have been completed within the Tar River basin:

• Act dated March 3, 1879, authorized the clearing of snags from the Tar River channel from Washington to Tarboro.

• Act dated September 19, 1890, authorized snagging debris from a 40-mile long reach of Fishing Creek, a tributary of the Tar River.

• Act dated June 22, 1936, authorized clearing of snags from the Tar River channel from Tarboro to Rocky Mount.

• Authorized under Section 2 of the Flood Control Act of August 28, 1937, clearing snags between Washington and Rocky Mount (mile 17 and 89, respectively) on the Tar River.

• Act dated September 3, 1954 (Section 208), authorized clearing snags from about 20-miles of Conetoe Creek, a tributary of the Tar River.

• Authorized February 6, 1964, under Section 205 of the 1948 Flood Control Act, as amended, construction of the 2.89-mile long earthen flood control levee to protect Princeville. Work was completed in September 1967.

• Authorized February 18, 1977 under Section 205, as amended, construction of a flood control levee around the Town of Speed, channel excavation and snagging of Deep Creek, a tributary of Fishing Creek, which is a tributary of the Tar River. Work was completed in 1983.

The following dams are located on the Tar River:

• Tar River Reservoir: In 1971, the City of Rocky Mount constructed the 1,860-acre Tar River Reservoir. The impoundment extends about 11 miles upstream of the dam.

Water supply was the primary purpose but it also provides recreational uses such as boating, fishing, hunting, and water skiing. Pursuant to the N.C. Dam Safety Act, the Tar River Reservoir Dam is required to provide a continuous downstream release of 80 cubic feet per second (cfs) in the Tar River (NCDENR 2004).

• Rocky Mount Mills Dam: This dam is also located in Rocky Mount and is the lowest dam on the Tar River (i.e., no other dam between it and Pamlico Sound). In 1909, Rocky Mount Mills constructed the 15-feet high stone dam, which is considered a “run of the river” impoundment. “Run of the river”, means that there is no flood pool and all waters reside within the existing river channel. Rocky Mount Mills Dam, an unlicensed hydropower facility, is required to provide, under the N.C. Dam Safety Act, a continuous, instantaneous minimum flow of 60 cfs in the natural channel directly below the dam, the bypassed reach. The dam is also required to have a calibrated staff gage on the dam crest or in the bypassed reach to monitor the flow requirement (NCDENR 2004).

Princeville, North Carolina Draft Report

8.14.3 PRESENT ACTIONS The Selected Plan consists of:

• Constructing flap gates on eight ungated culverts, and construction of several new culverts to address floodflow penetration and interior drainage issues, respectively;

• Modifying the intersection of N.C. Highway 33 and U.S. Highway 64, increasing elevations of the interchange of N.C. Hwy 33 and U.S. Hwy 64, by up to 4.5 feet;

• Installation of a “Shoulder Levee” parallel and adjacent to a low spot on Highway 64;

• Extension of the existing levee at the point of its current northern-most terminus along Highway 258, to the east, and then south, to its juncture with the approximate southern terminus of the project.

• Non-structural measures that consist of: Flood Warning and Evacuation Plan updates, Flood Risk Management Education and Communication Plans, and updating of Floodplain Management plans.

Evaluations by the USACE, along with discussions with representatives from the State and Federal agencies indicated that the proposed project would not have a significant impact on wetlands, wildlife habitat, 1% floodplain, farmlands (i.e., prime farmland soils), Threatened and Endangered species, cultural/historic, and socio-economic resources. These resource specific impacts are described in the preceding section of this report. The proposed action would affect 0.03 acre of wetlands and three tributary crossings, about 5.9 acres of cultivated field (within the proposed borrow area), 9.2 acres of prime farmland soils (3.3 acres of which is found underneath the raised paved road and grassed shoulders). No adverse impacts to endangered and threatened species, cultural resources, and socio-economic resources would occur.

The following information was taken from the N.C. Division of Water Resources, 2004 Tar-Pamlico River Basin-wide Water Quality Plan and the 1996 Land-sat Data for the Tar-Tar-Pamlico River Basin: Within the approximately 5,440-square mile (or 34,816,600 acres) Tar-Pamlico River Basin drainage area, currently about 470,460 acres of wetlands (Includes salt and freshwater marshes, and hardwood swamps) and 1,372,590 acres of vegetated upland riparian habitat. About 877,150 acres of the land area would be classified as 1% floodplain. Prime Farmland soils may be 18% of the land within the basin.

The proposed impacts of the Princeville, North Carolina Flood Risk Management Integrated Feasibility Reportare negligible when compared to the overall resources within the River Basin.

Additionally, the USACE Wilmington District ran the Hydrologic Engineering Center’s HEC-RAS model for the proposed action (Section 4.04). The results of the modeling show that the difference in water surface elevation (with and with-out the proposed Princeville Levee Extension Alignments) was less than 0.1 foot (i.e., less than 1.2 inches). Accordingly, this change in water surface elevation was not considered significant and would not increase flooding either in the City Tarboro or in any downstream communities.

8.14.4 REASONABLY FORESEEABLE FUTURE ACTIONS

Currently, discussions with USACE, Regulatory Division, the NCDOT, and NCDNR indicate that no major new future foreseeable projects are proposed within the Tar River Basin that would adversely impacts the following: Wetlands, Wildlife Habitat, 1% Floodplain, Farmlands (i.e., Prime Farmland Soils), Endangered and Threatened Species, and Tar River Riparian Buffer Area.

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To verify the fact that no major future foreseeable projects would take place within the Tar-Pamlico River Basin, the NCDWR, 2004 Tar-Tar-Pamlico River Basin-wide Water Quality Plan indicates that within the Tar River Basin only 1% of the land falls into the urban/built-up category (or 348,166 acres). Moreover, the following information in Table 8.1 reflects the current and estimated population in Edgecombe County.

Table 8.1: Current and estimated population in Edgecombe County (NC Office of State and Budget Management)

Population 2010

Population 2020

Estimated Population 2030

Population Change 2010 to 2020

Estimated

Population Change 2020 to 2030

Edgecombe

County 56,552 54,348 52,308 -2,204 -2,040

There does not appear to be any significant development pressure either within Edgecombe County or the Tar-Pamlico River basin that would adversely impact these important resources (i.e., wetlands, wildlife habitat, 1% floodplain, farmland (Prime Farmland Soils), Endangered and Threatened Species, Cultural Resources, Tar River Riparian Buffer area, and socio-economic resources).

Impacts of the “No Action” Alternative No adverse impacts are anticipated.

Impacts of the Proposed Action

Review of past, present or any possible future foreseeable projects in the Tar-Pamlico River Basin indicate that the proposed action would not produce a “cumulatively significant impact on the environment”.