How Many Lakes Are in New Jersey? Over 1,200—From Ponds to Giants

How Many Lakes Are in New Jersey? Over 1,200—From Ponds to Giants

New Jersey boasts over 1,200 lakes and ponds, ranging from tiny farm ponds to large reservoirs and natural glacial lakes.

Notable Examples

• Lake Hopatcong (Morris/Sussex) — 2,500 acres, largest natural lake; boating, fishing, lake life.
• Round Valley Reservoir (Hunterdon) — 2,350 acres, deepest (180 ft), trophy trout, scuba.
• Greenwood Lake (Passaic, NY border) — 1,920 acres, bi-state, heavy recreation.
• Lake Wawayanda (Sussex) — 255 acres, pristine, within Wawayanda State Park.
• Merrill Creek Reservoir (Warren) — 650 acres, clear, deep, no motorboats.

Types & Origins

• Glacial lakes: Kettle holes (Hopatcong, Wawayanda) — Ice Age legacy.
• Reservoirs: Dammed rivers for water supply (Round Valley, Merrill Creek, Spruce Run).
• Impoundments: Small dams for mill power, irrigation, recreation.
• Coastal lagoons: Barrier island lagoons (not always counted as "lakes").

Management

NJDEP monitors water quality, harmful algal blooms (HABs), invasive species (hydrilla, water chestnut). Many have public access via state parks, county parks, or municipal beaches.

Fun Fact

Despite being the 4th smallest state, NJ's lake density is high—thanks to glacial geology and dense water-supply infrastructure. You're never far from water.