An Overview of New Jersey's Rivers and Lakes

Largest and Famous Water Features

New Jersey is home to several prominent rivers, lakes, and reservoirs. The Delaware River is the largest and most famous, forming the state’s western border. Lake Hopatcong is the state's largest lake, popular for recreation and tourism. The Raritan River is another major waterway, flowing through central New Jersey. Other notable water features include the Manasquan Reservoir and the Passaic River, both significant for local ecosystems and human use.

Sources of Water for Rivers and Lakes

The rivers, lakes, and streams of New Jersey primarily receive water from rainfall and groundwater, rather than snowmelt from distant mountains. The Delaware River, however, is partly fed by streams and rivers originating in New York and Pennsylvania. Local watersheds, including those in the Highlands and Pine Barrens, also contribute significantly to the state’s water supply. The state’s lakes and reservoirs often rely on local rainwater and regional water management systems. Seasonal rainfall patterns play a critical role in maintaining water levels throughout the year.

Types of Rivers and Inland Waterways

New Jersey features several types of rivers, including perennial rivers like the Delaware and Raritan, which flow year-round. There are no exotic or distributary rivers, but tributary rivers like the Hackensack feed larger water systems. Man-made waterways, such as the Delaware and Raritan Canal, were historically important for transport and remain significant for water supply. Inland waterways like the Great Egg Harbor River are popular for recreation, and winding rivers such as the Musconetcong showcase natural bends and curves. Rapids are rare but can be found on smaller rivers during high water events.

Lake Types in New Jersey

New Jersey is home to various lake types, including anthropogenic lakes like the Manasquan Reservoir, created for water storage and recreation. Glacial lakes, such as Lake Hopatcong, were formed during the last Ice Age, while fluvial lakes like Merrill Creek Reservoir result from river processes. The state also has smaller shoreline lakes, particularly along the coast, and natural ponds scattered throughout the Pine Barrens. Most of the lakes are used for a combination of recreation, water storage, and conservation.

Direction of River Flow

New Jersey's rivers predominantly flow in a north-south direction, with examples like the Delaware River running southward toward the Atlantic Ocean. The Raritan River flows east-west before turning southward, draining into Raritan Bay. Some rivers in the northern part of the state, like the Passaic, exhibit more varied flow patterns due to the hilly terrain. The Pine Barrens' rivers, such as the Mullica, typically flow southward, emptying into the Atlantic Ocean.

Natural and Manmade Lakes

Many of New Jersey’s lakes are man-made, such as the Round Valley Reservoir, constructed by the New Jersey Water Supply Authority for water storage. Lake Hopatcong, although natural, was expanded by damming in the 19th century. Man-made lakes were often created by state and federal agencies for flood control, water supply, or recreation. Other examples include the Spruce Run Reservoir, which supports water supply and recreation. While most lakes in the state serve human purposes, a few natural lakes still exist, formed by glacial activity or other geological processes.

Rivers Used for Transportation

New Jersey’s rivers, particularly the Delaware River, play a role in commercial transportation. While the Delaware River supports shipping from the Port of Camden and Trenton, most rivers are not major transportation routes. Smaller rivers like the Raritan and Passaic are used for limited local transport but are primarily for recreational boating. In terms of cargo, the Delaware River facilitates substantial trade, though exact figures vary by year. Overall, commercial river transportation is secondary to the state's extensive road and rail networks.

Dams and Their Purposes

New Jersey has many dams, primarily used for flood control, water supply, and recreation. The Round Valley and Spruce Run reservoirs, created by damming rivers, store water for the region's needs. Some dams, such as those on the Delaware River, also help regulate water flow and prevent flooding. Smaller dams are found on rivers like the Raritan and Musconetcong, creating reservoirs that support recreation and wildlife habitats. Hydroelectric power generation is less common but does exist on a few smaller rivers.

Recreational Uses of Water Features

New Jersey's rivers, lakes, and reservoirs are popular for various recreational activities. Lake Hopatcong is a favorite for boating, jet skiing, and fishing, while the Delaware River is known for kayaking, canoeing, and tubing. The Manasquan Reservoir is another hotspot for fishing, hiking, and paddleboarding. Rivers like the Mullica and the Great Egg Harbor attract kayakers and wildlife enthusiasts. These water features draw many visitors each year, contributing significantly to the state’s outdoor recreation economy.

Agricultural Support from Water Features

The rivers and reservoirs in New Jersey provide vital support for the state's agricultural industry. The Delaware River, in particular, supplies irrigation water for farms in the western part of the state. Smaller rivers like the Raritan also play a role in local agriculture, especially for crops like corn and vegetables. Reservoirs such as Round Valley provide a steady water supply during dry periods, ensuring that farms have adequate resources. This water infrastructure is critical for sustaining New Jersey’s farming communities.

Pollution Issues in Rivers and Lakes

Several of New Jersey’s rivers and lakes have faced pollution problems over the years, particularly due to industrial runoff and urbanization. The Passaic River, for example, has a long history of pollution from nearby factories, resulting in contamination by hazardous chemicals. Cleanup efforts have been ongoing, though challenges remain. The Delaware River also experienced pollution issues in the past, but water quality has improved in recent decades. Urban stormwater runoff remains a concern, particularly for rivers near densely populated areas.