USACE CWMS - Delaware River 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 Delaware River is the longest un-dammed river east of the Mississippi River, extending 330 miles from the Catskill Mountains in New York to the mouth of the Delaware Bay where it flows into the Atlantic Ocean. The river is fed by 216 substantial tributaries, the largest of which are the Schuylkill and Lehigh Rivers in Pennsylvania. The watershed drains four-tenths of one percent of the total continental U.S. land area. In all, the basin contains 13,539 square miles draining the four states of New York, Pennsylvania, New Jersey, and Delaware.

Parts of five physiographic provinces lie within the Delaware River Basin. These are the Coastal Plain, Piedmont, New England, Valley and Ridge, and Appalachian Plateaus. Topography varies from the relatively flat Coastal Plain, which consists of unconsolidated sediments, to rolling lowlands and a series of broad uplands in the Piedmont. North of the Piedmont Province, the New England and the Valley and Ridge Provinces consist of rock layers that have been deformed into a series of steep ridges and parallel folds that trend northeast-southwest. The Appalachian Plateaus occupy the upper one-third of the basin and are characterized by rugged hills with intricately dissected plateaus and broad ridges. Altitude in the basin increases from sea level in the south to more than 4,000 feet in the north. During the last major glacial advance, the Appalachian Plateaus and parts of the Valley and Ridge and the New England Provinces were glaciated. North of the line of glaciation, valleys typically are underlain by thick layers of stratified drift and till.

Average annual precipitation ranges from 42 inches in southern New Jersey to about 50 inches in the Catskill Mountains of southern New York; annual snowfall ranges from 13 inches in southern New Jersey to about 80 inches in the Catskill Mountains. Generally, precipitation is evenly distributed throughout the year. Annual average temperatures range from 56 degrees Fahrenheit in Southern New Jersey to 45 degrees Fahrenheit in Southern New York.

Approximately five percent of the nation’s population (15 million people) relies on the waters of the Delaware River Basin for drinking and industrial use. The Catskill Mountain Region in the upper basin provides New York City (NYC) with a high quality source of water from three basin reservoirs, Cannonsville, Pepacton, and Neversink. Nearly half of its municipal water supply comes from these reservoirs that is diverted from the Delaware River Watershed. Within the basin, the river supplies drinking water to much of the Philadelphia metropolitan area and major portions of New Jersey, both within and outside of the basin.

From the Delaware River’s headwater in New York to the Delaware Estuary and Bay, the river also serves as an ecological and recreational resource. Over the past half century, as a result of the maintenance of minimum flow targets at Montague and Trenton, NJ, cold-water fisheries have been established in the East Branch Delaware, West Branch Delaware, Nerversink River and the upper main-stem Delaware River. Most of the main-stem upstream of Trenton, NJ has been designated by Congress as part of the Federal Wild and Scenic River System.

There are numerous economic benefits from the river. The Delaware River Port Complex (including docking facilities in Pennsylvania, New Jersey, and Delaware) is the largest freshwater port in the world. According to testimony submitted to a U.S. House of Representatives subcommittee in 2005, the port complex generates $19 billion in annual economic activity. It is one of only 14 strategic ports in the nation transporting military supplies and equipment by vessel to support troops overseas. The Delaware River and Bay is home to the third largest petrochemical port, as well as five of the largest east coast refineries. Nearly 42 million gallons of crude oil are moved on the Delaware River on a daily basis. There are approximately 3,000 deep draft vessel arrivals each year and it is the largest receiving port in the United States for Very Large Crude Carriers (tank ships greater than 125,000 deadweight tons). It is the largest North American port for steel, paper, and meat imports as well as the largest importer of cocoa beans and fruit on the east coast.

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：

- GeoHMS（地理空间水文建模扩展）（Geospatial Hydrologic Modeling Extension）
- ResSIM（水库系统模拟）（Reservoir System Simulation）
- RAS（河流分析系统）（River Analysis System）
- FIA（洪水影响分析）（Flood Impact Analysis）

特拉华河是密西西比河以东最长的未筑坝河流，全长330英里，从纽约州卡茨基尔山脉延伸至特拉华湾的河口，流入大西洋。该河流由216条主要支流滋养，其中最大的支流为宾夕法尼亚州的施尤尔克河和利希河。流域面积占总美国大陆陆地面积的百分之四十分之一。总的来说，该流域包含13,539平方英里，流经纽约、宾夕法尼亚、新泽西和特拉华四个州。

特拉华河流域内分布着五个地理景观区域的部分地区。这些地区包括海岸平原、皮德蒙特、新英格兰、山谷和脊地以及阿巴拉契亚高原。地形从相对平坦的海岸平原（由非固结沉积物组成）到皮德蒙特地区的起伏低地和一系列广阔的高地不等。皮德蒙特省以北，新英格兰和山谷与脊地区由岩石层构成，这些岩石层已变形为一系列东北-西南走向的陡峭山脊和平行褶皱。阿巴拉契亚高原占据流域的上三分之一，以其崎岖的山丘、错综复杂的分割高原和宽阔的山脊为特征。流域内的海拔从南部的海平面上升到北部的4,000多英尺。在上一次主要的冰川前进期间，阿巴拉契亚高原以及山谷与脊地区和新英格兰地区的一部分被冰川覆盖。冰川线以北，山谷通常由厚厚的层状漂积物和冰碛层构成。

年平均降水量从新泽西州南部的42英寸到纽约州南部卡茨基尔山脉的约50英寸不等；年降雪量从新泽西州南部的13英寸到卡茨基尔山脉的约80英寸不等。一般来说，降水量在全年均匀分布。年平均温度从新泽西州南部的56华氏度到纽约州南部的45华氏度不等。

大约有全国百分之五的人口（1500万人）依赖特拉华河流域的水源用于饮用和工业用途。上流域的卡茨基尔山脉地区为纽约市（NYC）提供了来自三个流域水库——坎农维尔、佩帕克顿和内弗辛克的高质量水源。其市政用水供应中近一半来自这些从特拉华河流域调水的 reservoirs。在流域内，河流为费城大都会地区以及新泽西州内外的广大地区提供了饮用水。

从特拉华河的源头（纽约州）到特拉华河三角洲和湾口，该河流还充当了生态和休闲资源。在过去半个世纪中，由于在蒙塔古和新泽西州特伦顿维持最低流量目标，东支特拉华河、西支特拉华河、内弗辛克河以及上游主河段的特拉华河都建立了冷水渔业。新泽西州特伦顿上游的大部分主河段已被国会指定为联邦荒野和风景河系统的一部分。

河流带来了众多的经济效益。特拉华河港口综合体（包括宾夕法尼亚州、新泽西州和特拉华州的码头设施）是世界上最大的淡水港口。根据2005年提交给美国众议院小组委员会的证词，该港口综合体每年产生190亿美元的经济活动。它是全国仅有的14个战略港口之一，通过船只运输军事供应和设备以支持海外部队。特拉华河和湾是第三大石油化学港口，以及东海岸最大的五家炼油厂的所在地。每天有近4200万加仑的原油在特拉华河上运输。每年约有3,000艘深水船抵达，它是美国最大的超大型原油运输船（吨位超过125,000吨的油轮）接收港口。它是北美最大的钢铁、纸张和肉类进口港口，以及东海岸最大的可可豆和水果进口商。