Round Valley Reservoir Fishing: Lake Trout and Brown Trout

Round Valley Reservoir in Hunterdon County is New Jersey’s best-known trophy trout water. It is a deep water-supply reservoir that holds lake trout, brown trout and rainbow trout, plus largemouth and smallmouth bass, and it is the only place in the state where lake trout are a regular target. It also changed its rules for 2026, so some of what older articles say is out of date. This guide covers the current rules we verified, the access and boating limits, how anglers fish it and where our sources are dated.

What the 2026 rules say

The rules snapshot above lists the figures from New Jersey’s trout and freshwater tables. In plain terms:

• Brown and rainbow trout: 15 inch minimum and two a day, combined.
• Lake trout: open all year. The limit is eight fish of 15 to under 24 inches plus one fish of 24 inches or longer, nine in total. For 2026 the total went up from seven, and the old catch-and-release closure from September 16 to November 30 was removed.
• Bass: Round Valley was added to the Lunker Bass Lakes for 2026. Largemouth and smallmouth together are limited to three fish of at least 15 inches.
• Trout stamp: the fee table lists a trout stamp for anglers 16 to 69. Check the license page for the stamp requirement before you fish for trout.

Older pages, including a 2007 state spotlight and some magazine pieces, give a 20 inch minimum and one lake trout, or a closed season in the fall. Those are obsolete. Because the reservoir’s rules change from year to year, we set this page to be rechecked in January and February.

The water

New Jersey Fish and Wildlife’s 2007 spotlight describes a 2,350-acre water supply reservoir in Hunterdon County managed as a trophy trout lake, with two boat ramps off Round Valley Access Road (Route 629) and a third launch for campers. The Fisherman describes depths near 200 feet, while other sources give about 180, so we do not state a maximum. The same magazine says the surface can reach 80 degrees in a hot spell while the bottom stays near 50, which is the reason lake trout hold deep in summer. The 2007 survey electrofished over 820 fish of 19 species in a night. Bluegill were the most common, followed by largemouth bass and smallmouth bass, and the sample also caught brown and rainbow trout. That is a survey from nearly twenty years ago, so use it for the mix of fish and not for numbers.

Boating and access

• Motors: the state spotlight and The Fisherman both say outboards are limited to 9.9 horsepower.
• Ramp permits: licensed anglers can launch free with a photocopy of their license. Others need a Boat Ramp Maintenance Permit, which the state’s fee table lists at $15. The state page that describes the process is from 2007, so confirm how to buy one.
• Wind lights: The Fisherman reports that when the flashing lights at the ramp, the dam tops and the south end are on, winds are above 35 mph and no craft may launch. The article is undated, so confirm the rule with the park.
• Shore fishing: a December 2022 Fisherman article said the reservoir was at its lowest level since it was filled in the 1960s because of dam work, and described fishing from the rip-rap near parking lot 2. Water levels and walkway closures change, so look at the park page before you go.
• Ramp closures: a recent notice said the lower ramp, kayak launch and lower gravel lot were closed October 9 to 24, 2025 for dock work. Ramp status can change.

How anglers fish it

The following comes from The Fisherman and from the older state spotlight. It is a description of what anglers do, not a guarantee.

• Lake trout: herring is the bait of choice, fished deep with an egg sinker, and some anglers troll with downriggers or lead-core line. The 2022 article said the fish bite best when the water is around 22 degrees or colder, which is winter.
• Brown and rainbow trout: slip floats and flat lines at 20 to 50 feet are the standard approach, and from shore a rig with a three-quarter-ounce egg sinker, a leader of three or four feet and a small hook baited with a mealworm or a bait paste is typical. The Fisherman says the state no longer stocks browns, and that the Round Valley Trout Association stocks them in spring and puts shiners in the reservoir each fall. The state spotlight mentions alewives being stocked as forage.
• Bass: the 2007 survey found largemouth up to 7.2 pounds and smallmouth to 3.4 pounds, so bass are worth a cast, and they are now under the Lunker rule.

Dock Tale: two state records, one reservoir

The Fisherman’s hot-spot page credits Round Valley with the state records for lake trout, listed at 32 pounds 8 ounces, and brown trout, listed at 21 pounds 6 ounces and credited to a 1995 catch. The magazine says the lake trout record was “in jeopardy.” A state eel record of 6 pounds 13 ounces also came from this reservoir in 2005, according to the 2007 spotlight. We have not checked whether any of these records has since changed, so look at the state record list before you quote them.

Gear that works

A medium-heavy spinning or conventional rod around seven feet works for trolling and for fishing a heavy bait deep. For the shoreline trout rig described above, a longer and lighter rod helps you cast a weight and keep a bite sensitive. Heavy sinkers and braid need a rod with real backbone. Tell us how you fish and we will build to it.

Safety

• Wind on this reservoir builds quickly. Obey the wind lights and do not launch a small boat when they are flashing.
• Cold water is dangerous in the shoulder seasons. Wear a life jacket.
• Fish advisories: we did not read New Jersey’s consumption advisory for Round Valley, so check it before you keep a fish.

For the other trout waters in the state, see the New Jersey trout guide, and for lakes best lakes for fishing in New Jersey. The rules guide covers licenses and stamps.