USACE CWMS - Cape Fear Watershed

The Corps Water Management System (CWMS) includes four interrelated models to assist with water management for the basin:
- GeoHMS (Geospatial Hydrologic Modeling Extension)
- ResSIM (Reservoir System Simulation)
- RAS (River Analysis System)
- FIA (Flood Impact Analysis)

The Cape Fear watershed headwaters are in the Piedmont geographic region characterized by relatively low, rolling hills extending into the Upper Coastal and Lower Coastal plains characterized predominantly by wetlands in the middle to southeast portions of the watershed. Elevations range from 900 feet in the western hills to sea level at the mouth of the Cape Fear River in Wilmington. Average annual precipitation in the Cape Fear watershed ranges from 42 inches in Greensboro near the head waters to 57 inches in Wilmington on the coast. The Greensboro area average annual snowfall of 9 inches. However, runoff due to snowmelt is generally not a concern in this watershed.

Within the Cape Fear basin, there is one USACE reservoir project. The project is the B. Everett Jordan Dam and Lake on the Haw River approximately 4 miles upstream of the confluence of the Deep River which creates the Cape Fear River. The project purposes include flood control, water supply, recreation, fish and wildlife enhancement, and augmentation of low flows for the purposes of pollution abatement and water-quality control in the Cape Fear River Basin.

Other locks and dams on the Cape Fear River include Buckhorn Lake Dam, Huske Lock and Dam, Lock and Dam #1 and Lock and Dam #2. Buckhorn Lake Dam creates a backwater effect at the tailrace of the B. Everett Jordan Dam. The Shearon Harris Lake Dam is located on Buckhorn Creek and serves the Shearon Harris Nuclear Power Plant, Unit 1 located in New Hill, NC. The plant is operated by Carolina Power & Light Company.

A few of the notable tributaries to the Cape Fear River include Turnbull Creek, Harrisons Creek, Rockfish
Creek, Little River, Upper Little River, Buckhorn Creek, Deep River and Haw River. Tributaries to the Haw River upstream of the B. Everett Jordan Dam include New Hope River, Cane Creek, Big Alamance Creek, Back Creek, Stony Creek, and Reedy Fork.

The key inflow gages in the basin include Haw River at Haw River, Haw River near Bynum, Morgan
Creek near Chapel Hill and New Hope Creek near Blands. Key gages downstream of B. Everett Jordan Dam are Deep River at Moncure, Cape Fear River at Lillington and Cape Fear River at Fayetteville.

During flood control operations, the primary objective of B. Everett Jordan reservoir is to control floods along the Cape Fear River, particularly in the vicinity of Fayetteville. The basic plan of operation is to maintain a normal pool elevation of 216 feet, mean sea level (msl), by releasing inflows up to nondamage stages in the downstream reaches of the river. The non-damage stage at Fayetteville is 31 feet at the river gage. The effects of runoff from uncontrolled drainage areas on Fayetteville stages is forecast by monitoring flows at the Deep River at Moncure gage, the Cape Fear River at Lillington gage and the Cape Fear River at Fayetteville gage. Flows from the Deep River are particularly significant.

An objective of water quality control at B. Everett Jordan Lake is meeting the North Carolina and Environmental Protection Agency (EPA) standards for both the impounded water and the river water below the dam. For low flow regulation, 94,600 acre-feet (67%) of water quality storage is reserved in the conservation pool of Jordan Lake for release during critically dry periods. 45,800 acre-feet (33%) of the conservation pool storage is reserved for water quality. A required minimum instantaneous flow of 40 cfs is maintained immediately below the dam. Releases are made from the conservation pool storage allocated to water quality as necessary to maintain a minimum of 600 cfs as measured at the Lillington stream gage. Occasionally, the flow at Lillington may drop below 600 cfs because of variations in river flows induced by small hydroelectric plants located on the Deep River.

Corps 水资源管理系统（CWMS）包含四个相互关联的模型，旨在协助流域水资源管理：
- 地理水文模型扩展（GeoHMS）
- 水库系统模拟（ResSIM）
- 河流分析系统（RAS）
- 洪水影响分析（FIA）

卡普费尔流域的源头位于皮德蒙特地理区域，该区域以相对低矮、起伏的山丘为特征，延伸至上沿海平原和下沿海平原，流域中至东南部主要由湿地构成。海拔高度从西部山丘的900英尺到卡普费尔河在威尔明顿入海口的海平面不等。卡普费尔流域的平均年降水量从源头附近的格林斯伯勒的42英寸到沿海的威尔明顿的57英寸不等。格林斯伯勒地区的平均年降雪量为9英寸。然而，由于融雪引起的径流在此流域通常不是关注的重点。

在卡普费尔流域内，有一个美国陆军工程兵团（USACE）的水库项目。该项目是位于哈河上游约4英里处的B.埃弗雷特·乔丹大坝和湖泊。该项目的目标包括防洪、供水、休闲娱乐、鱼类和野生动物保护，以及为污染控制和水质管理而增加卡普费尔河流域的最低流量。

卡普费尔河上的其他船闸和大坝包括巴克霍恩湖大坝、胡斯克船闸和大坝、船闸和大坝#1以及船闸和大坝#2。巴克霍恩湖大坝在B.埃弗雷特·乔丹大坝下游尾水处产生回水效应。谢尔登·哈里斯湖大坝位于巴克霍恩溪上，为位于北卡罗来纳州纽希尔的新希尔谢尔登·哈里斯核电站（1号机组）提供服务。该电站由卡罗来纳电力与照明公司运营。

卡普费尔河的一些著名支流包括图尔本溪、哈里森溪、鲑鱼溪、小河、上游小河、巴克霍恩溪、深河和哈河。B.埃弗雷特·乔丹大坝上游的哈河支流包括新希望河、甘蔗溪、大阿拉姆西溪、后溪、斯托尼溪和里迪 Fork。

流域中的关键流量监测站包括哈河在哈河、哈河在比努姆附近、摩根溪在查珀希尔附近以及在新布兰兹附近的新希望溪。B.埃弗雷特·乔丹大坝下游的关键监测站包括在莫纳科尔附近的深河、在利林顿附近的卡普费尔河以及在费耶特维尔附近的卡普费尔河。

在防洪作业期间，B.埃弗雷特·乔丹水库的主要目标是控制卡普费尔河的洪水，特别是在费耶特维尔附近。基本操作计划是通过释放下游河段的非损害流量来维持216英尺的正常池水位，即平均海平面（msl）。在费耶特维尔的非损害水位是河流流量计处的31英尺。通过监测莫纳科尔深河流量计、利林顿卡普费尔河流量计和费耶特维尔卡普费尔河流量计的流量，预测未受控制排水区径流对费耶特维尔水位的影响。深河的流量尤其重要。

在B.埃弗雷特·乔丹湖的水质控制目标中，是满足北卡罗来纳州和环境保护署（EPA）对蓄水区和坝下河水的标准。对于低流量调节，乔丹湖的储备池中保留了94,600英亩英尺（67%）的水质储备，以在极度干旱期间释放。储备池储备的45,800英亩英尺（33%）用于水质。在坝下立即维持40立方英尺每秒的最低瞬时流量。根据利林顿河流流量计的测量值，在必要时从分配给水质的水质储备池中释放流量。偶尔，由于深河上的小型水电站引起的河流流量变化，利林顿的流量可能会降至600立方英尺每秒以下。