Raritan River Fishing Guides and Conditions, New Jersey

About the Raritan River

The Raritan is the largest river contained entirely within New Jersey, formed at Branchburg where the North Branch and the South Branch come together. The USGS gauge at Manville sits just below that confluence and watches about seven hundred and eighty-five square miles. It carries a live water temperature series along with discharge and stage, which is useful on a river that straddles the line between trout water and warmwater and shifts across it seasonally.

Above the confluence the two branches are the trout fishery. The South Branch in particular, through Ken Lockwood Gorge and the Clinton reach, is among the better-known stocked and holdover trout water in the state and is managed with special regulations in places. Below the confluence the main stem broadens, warms and becomes a smallmouth bass river, and that is what the Manville gauge watches. Smallmouth are the primary sport fish through the main stem, with largemouth in the slower stretches, channel catfish throughout, and common carp abundant enough to support a dedicated following.

Migratory fish are part of the story again. Dam removals on the lower Raritan, including work at the Calco and Robert Street sites, have reopened passage from tidewater, and American shad and river herring have regained access to reaches they had been shut out of for well over a century. The lower river below Manville runs toward New Brunswick and becomes tidal before reaching Raritan Bay.

This is a densely settled valley and the river reflects it, running past towns, highways and old industrial sites, but it is genuinely fishable and heavily used. Flooding is a real feature here – Manville has a long history of it – and the gauge is watched as much for high water as for fishing conditions.

Access

Manville gauge and Duke Island Park - the flow and temperature reference with broad park frontage.
Confluence at Branchburg - where the North and South branches meet.
Ken Lockwood Gorge, South Branch - special-regulation trout water upstream.
Raritan River Greenway access points - walk-in bank fishing through the middle river.
Bound Brook and former Calco Dam site - restored passage water on the lower river.
Johnson Park, Piscataway - lower-river bank access near tidewater.
New Brunswick landing - the tidal reach at the bottom of the river.

Seasons

Spring: high and cold; trout stocking on the branches and shad moving into the lower river.
Summer: warm and low; smallmouth and catfish carry the main stem, best early and late.
Fall: steady flows and strong smallmouth fishing through October.
Winter: cold and high after storms, with limited fishing outside mild spells.