The Delaware River's two main branches — the West Branch below Cannonsville Reservoir and the East Branch below Pepacton Reservoir — are the best tailwater trout rivers in the Northeast, and by many measures the best dry fly rivers east of the Mississippi. They're within three hours of New York City, they hold wild trout of legitimate size, and the hatch diversity is as good as anything in the classic Catskill rivers downstream. Yet outside of the serious fly fishing world, they remain underknown and relatively lightly pressured compared to what their quality merits.
The System: Why Tailwaters Change Everything
Both branches of the Upper Delaware are dam-controlled tailwaters. The Cannonsville and Pepacton Reservoirs (part of New York City's water supply system) release cold water from depth year-round, maintaining trout temperatures through the summer when the natural watershed water would be too warm.
The practical implications:
No runoff season for trout fishing. While spring floods affect the river's color and wade-ability, the cold water is always there underneath. The tailwaters fish in conditions that push other Catskill streams out.
Year-round trout populations. Wild rainbow and brown trout survive the Catskill summer on the branches when the Beaverkill and Willowemoc below are too warm. The branches have become the primary wild trout fishery of the Catskill system.
Large fish. The cold, consistent water and excellent food supply — the tailwaters grow exceptional insect populations — produce wild trout that average substantially larger than the classic Catskill streams. Wild rainbows to 20 inches and wild browns to 24 are realistic expectations if not everyday catches.
Species: Wild rainbow trout (dominant on the West Branch particularly), wild brown trout (strong on the East Branch and the main stem), wild brook trout (in cold tributaries). All wild — no stocking on the upper branches. The wild rainbow population on the West Branch below Cannonsville is one of the best in the Northeast.
West Branch Delaware
The tailwater character
Cannonsville Dam to Hale Eddy
The West Branch immediately below Cannonsville Dam is the coldest and most productive tailwater reach. The river in this section runs cold, clear, and wide — 60 to 100 yards in most stretches — with classic riffle-run-pool structure and long, flat tailouts where rising fish are visible at distance. Wade fishing is excellent here; the flows are generally manageable except during high-release periods.
Wild rainbow trout are the dominant species on the upper West Branch, with fish that average in the 14–18 inch range and individuals consistently above 20 inches. These are not stocked fish on hatchery schedules — they're wild trout conditioned to a complex, hatch-driven food supply, and they're correspondingly selective when hatches are on.
Flow management
NYC DEP releases — check before you go
Delaware River water is managed by the Delaware River Basin Commission and New York City's Department of Environmental Protection. Both reservoirs release water according to downstream flow requirements, interstate agreements, and drought protocols. The releases can change day to day and affect wading conditions significantly.
The West Branch flows are tracked at the USGS gauge at Stilesville. A flow of 150–400 cfs is ideal for wade fishing the upper branch; above 600 cfs the wade fishing becomes challenging in the wider sections. The flows are published in real time — checking the gauge before a trip is essential.
Thermal refugia and summer low-flow periods. During drought years, NYC DEP may reduce reservoir releases to conserve water supply, and the Delaware branches can warm into the upper 60s°F in August. DRBC monitors temperatures and issues fishing advisories when thermal thresholds are exceeded. Check conditions before any summer trip.
East Branch Delaware
The East Branch below Pepacton Reservoir is narrower and more intimate than the West Branch — a wade fisher's river where long riffles give way to deep pools in a wooded valley. Brown trout dominate the East Branch, with rainbows less abundant than on the West Branch.
The East Branch fishes well from the dam downstream through Margaretville and beyond. Access is through public access sites and the road that follows the river (Route 28 parallels the lower East Branch). The river widens as it approaches the confluence with the West Branch at Hancock, where the two branches meet to form the main stem Delaware.
The main stem Delaware below Hancock is the confluence water — bigger, wider, and known for both exceptional dry fly fishing (particularly for rising wild brown and rainbow trout) and for the large smallmouth bass that share the water and take dry flies equally aggressively. The main stem below Hancock is one of the best and most accessible float fishing destinations in the Northeast.
Hatches on the Delaware Branches
The hatches on the Delaware branches are what draw serious fly fishers from across the region. The cold tailwater temperatures and rich macroinvertebrate communities produce hatches of quality and quantity that rival anything in the Catskill tradition.
Hendrickson: late April – May
the season opener
The Hendrickson (Ephemerella subvaria) hatch opens the major Catskill season. The branches typically run 1–2 weeks behind the Beaverkill downstream, meaning the Hendrickson can last longer at the tailwater temperatures. Afternoon emergences from 2–5 PM on warm days bring consistent rising fish.
Sulphurs: May – July
the workhorse hatch
Sulphurs run through May and into July on the branches — evening hatches that are the most sustained and reliable of the season. The tailwater temperatures extend the Sulphur window significantly beyond what the lower Catskill streams see. Spinner falls from both Sulphur and Pale Evening Dun species can be dense and produce excellent dry fly fishing into dark.
Green Drake and Brown Drake: late May – June
the major events
The Green Drake and Brown Drake emerge on the branches in late May and June, respectively — large, dramatic hatches that trigger the most aggressive surface feeding of the year. The Brown Drake emergence typically happens at dusk and into darkness, similar to the Hex hatch dynamic in Michigan. Carry large imitations (#10–#12) for both species and be prepared to fish low light.
Summer midges and Tricos: July – September
technical fishing
The tailwater summer is dominated by midges and Trico spinner falls — small (#20–#24), technical, and productive for patient anglers with fine tippet. The cold water keeps fish active and feeding through the heat of the summer when lower rivers are too warm to fish ethically.
Access and Regulations
The Upper Delaware branches are in New York State, and standard New York fishing licenses apply. Both branches have special regulations on specific sections — check New York DEC's current regulations for the Delaware watershed, as no-kill sections and artificial-only requirements apply to portions of both branches.
Public access on both branches is documented through NYDEC and the Delaware River Basin Commission. Canoe access sites, pull-outs, and marked public fishing sites are distributed throughout the upper branches. The Delaware branches are also within reach of the Catskill Fly Fishing Center and Museum in Livingston Manor, which makes a good base for anglers exploring both the classic Catskill rivers and the upper branches.
See the New York regulations guide for current license requirements, special regulation sections, and the Delaware watershed rules.