Harriman Reservoir

Harriman Reservoir — many maps and locals say Lake Whitingham — fills eight miles of the Deerfield River valley between Wilmington and Whitingham in southern Vermont. Created in 1923 by Harriman Dam, it remains the largest body of water lying entirely within the state: 2,040 acres, 28 miles of mostly forested shoreline, and depths to 180 feet near the dam. The surrounding Green Mountain country and a largely undeveloped shoreline give this working hydropower reservoir a surprisingly wild feel.

The fishery is genuinely two-story. Cold, deep water supports brook trout, brown trout, rainbows, and even lake trout and salmon, while the warmer coves and rocky shorelines hold one of southern Vermont's best smallmouth bass populations. For fly anglers the headline in recent years is the trophy trout program: under the 2026 Vermont F&W trophy stocking plan, Harriman receives 1,000 two-year-old brook trout — chunky, foot-plus fish that provide immediate, catchable quality in the reservoir's cool margins, especially in the weeks after spring stocking.

The fly season opens with ice-out in April, when trout cruise the shorelines and tributary mouths and a streamer or leech worked along the banks is deadly. As the water warms toward summer, trout slide deeper and attention turns to the smallmouth, which move shallow to spawn in late May and June and stay reachable on poppers and crayfish patterns all summer along the rocky western shore and the ledges near Mountain Mills. Fall cools the surface, brings trout back within reach, and paints the valley in color.

Harriman's water level fluctuates with hydropower operations — expect a drawn-down look by late season, with exposed shoreline and repositioned structure — and wind can funnel down the valley, but the reservoir's size and multiple launches (Mountain Mills near Wilmington, Ward's Cove, and the Whitingham end) let small boats find a lee most days. Anglers should note the reservoir's history and character: this is big, cold, serious water, and the same depth that grows its fish demands respect from paddlers.

For the traveling angler, Harriman pairs naturally with the Deerfield River itself: the tailwater sections below the reservoir's dam system offer some of New England's best river fishing, and a Wilmington-based trip can split mornings on the reservoir with evenings on the river. Between the trophy brookies, the smallmouth, and that pairing, Harriman anchors southern Vermont stillwater fishing.

Harriman is a long, deep, cold-water reservoir with a drowned-river-valley shape: steep, rocky western shorelines, broader coves and flats near the inlets, and a deep old river channel winding toward the dam. Water is clear to lightly stained. Levels fluctuate seasonally with power generation, exposing gravel and stump fields at low water.

Forage includes rainbow smelt, shiners, yellow perch, and abundant crayfish — the last driving the smallmouth fishery. Insect life is solid if not spectacular: chironomids throughout, damselflies and dragonflies in the weedy coves, Hexagenia over silty flats in early summer, and flying-ant falls in late summer that can bring every fish in the reservoir up at once.

A popular southern Vermont ice fishery for trout, salmon, and perch in season, with most effort near Mountain Mills and the Whitingham end. Fluctuating winter water levels can create shoreline ice hazards; approach with caution and local knowledge.