Susquehanna smallmouth on the fly

The Susquehanna River runs 444 miles from Cooperstown, New York to the Chesapeake Bay, draining 27,500 square miles through Pennsylvania and Maryland. Its smallmouth bass fishery is one of the largest in the eastern United States — not the most technically demanding, not the most remote, but for sheer fish density and accessible wading water within a few hours of the Mid-Atlantic population centers, nothing else competes.

The river's width ranges from 600 feet to over a mile in Pennsylvania. It sounds intimidating until you learn that smallmouth in large rivers use the same structure principles as trout in small streams — seams, edges, rock cover, current breaks — and the Susquehanna's braided channels, wading bars, and island complexes create the same kinds of holding water you'd find on any freestone trout stream, just wider.

Quick reference

Factor Detail
Location North-central PA through south-central PA into MD
Key access areas Harrisburg to Havre de Grace; Sunbury to Lock Haven in upper sections
Primary species Smallmouth bass; walleye in some sections; channel catfish
Average fish size 10-14 inches; 15-18 inch fish common; 20+ inch fish present
Best seasons Late May through October; peak July-August
Water type Large freestone river; moderate gradient; braided channels
Regulations PA Fish & Boat Commission (PA); MD DNR (MD); size/season rules vary by section
Crowds Heavy at known access points; light on midweek walks to mid-river structure

Why the Susquehanna for fly fishing

Fly gear is not the conventional choice on the Susquehanna — spin gear dominates — which makes it unusually productive for fly anglers during summer low water. The fish encounter far fewer flies than lures. A well-presented Clouser Minnow or crawfish pattern on a 6-weight moves fish that have seen 10,000 Mepps spinners.

The second advantage is the wading access. During summer flows (600-2,000 cfs at the Harrisburg gauge, depending on section), Susquehanna smallmouth concentrate on the shoals and gravel bars that become wade-able — vast stretches of cobble and rock that hold fish in inches to knee-deep water during low-water season. A spin angler in a boat has to anchor and cast to the same shoal. A wading fly angler can position at the fish's eye level and target structure that boat anglers can't reach from their angle.

Key sections

Upper Susquehanna — Sunbury to Harrisburg (PA)

The upper section runs through the broadest part of the river, with the most island and braid character. The West Branch and North Branch tributaries join the main stem above Sunbury, making the upper river the largest-volume section. Fish densities are high in summer; pressure is lower than the Harrisburg reach because access requires longer walks to mid-river structure.

Best access points: Northumberland (SR 147 south access to islands), Liverpool (Perry County side, island access at low flows), Clark's Ferry Bridge, Duncan's Island at the confluence.

Character: The island complexes throughout this section create seam-rich fishing. Islands create the classic large-river structure: fast water on the main channel side, slow backwater on the inside, and seam edges everywhere. Smallmouth hold on the upstream face of islands in heavy water, in the downstream tailout current seams, and in the island-adjacent riffles.

Central Susquehanna — Harrisburg to Safe Harbor Dam (PA)

The Harrisburg reach is the most-fished stretch and deservedly so — the combination of wading access, consistent summer flows, and dense smallmouth populations makes it the starting point for most new-to-the-Susquehanna fly anglers.

Best access points: Dock Street Dam area (below Harrisburg), Brunner Island (York County), Long Level (York County Marina), Highpoint Scenic Area (York County).

Character: Moderately wide (500-800 ft in most places) with extensive shoal systems at mid-river. Summer flows concentrate fish on shoal edges — look for the seam where the shoal gravel drops off into deeper run. That transition is where smallmouth stack, facing into the current to intercept crayfish, hellgrammites, and baitfish.

Wading approach: The Susquehanna's floor is slippery sandstone and cobble — algae-coated in summer. Felt soles or rubber with lugs, and a wading staff. The main channel is not wade-able and is frequently deep and fast; stay on the shoals and approach mid-river structure by reading the bottom color (pale tan = fishable shoal; dark = deeper run).

Lower Susquehanna — Safe Harbor to Havre de Grace (PA/MD)

Below Safe Harbor Dam, the character changes: deeper, slower, wider. The conowingo impoundment backs water through much of the lower PA section. Below Conowingo Dam, the river enters tidal influence and transitions to largemouth bass and striped bass territory — still excellent fishing, but a different species and technique.

Best smallmouth access (lower section): Peach Bottom, PA; Susquehanna State Park, Havre de Grace, MD (for dam tailwater fish below Conowingo).

Season and conditions

Smallmouth bass on the Susquehanna follow water temperature, not the calendar. The productive fly fishing window opens when water temperatures cross 58°F (late May most years) and closes when they drop back below 55°F in October.

Month Water temp Fish behavior Best approach
May 58-68°F Post-spawn; actively feeding Streamers and crayfish near structure
June 68-75°F Peak pre-heat activity; morning and evening best Poppers at dawn/dusk; nymphs mid-day
July-August 72-80°F Heat stress; fish move to oxygenated shallows pre-dawn and post-dusk Early morning topwater; weighted crayfish patterns in runs
September 65-72°F Cooling water; feeding intensity increases All techniques productive; streamers work all day
October 55-65°F Final pre-winter feed; big fish move shallow Streamer and crayfish prime; some topwater evening

Low-water bonus: July and August produce the lowest summer flows and the best wading access — the same conditions that concentrate fish on shoals. Heat-stressed fish are less active during midday but extremely aggressive in the 45-minute window before full sunrise and the first hour after sunset.

Flies and gear

Topwater: Poppers are the signature Susquehanna experience. Deer-hair poppers in yellow or chartreuse on size 2-4 hooks produce explosive strikes on low-light shoal fishing. Gurgler patterns in white or olive cover more water with less noise. Fish poppers on a 3-4 second pause between strips — the pause triggers strikes more reliably than constant motion.

Streamers (subsurface): The Clouser Minnow (size 2-6, chartreuse/white or olive/white) is the Susquehanna benchmark. Barr's Meat Whistle in olive or brown covers the deeper current edge presentations. Woolly Buggers in black and olive provide a sink-and-draw action that triggers reactionary strikes from larger fish.

Crayfish imitations: Crayfish are the dominant food source in the shoal habitat. Whitlock's Near Nuff Crayfish, Barry Beck's Crayfish, and the heavily-weighted Mercer's Craw work best dead-drifted along the bottom of shoal edges with short, drag-inducing mends.

Surface poppers and frogs: Elk hair poppers, Umpqua Swimming Frog, and Dahlberg Divers produce the most memorable strikes but require water temperatures above 65°F and calm surface conditions.

Gear

A 6-weight is the Susquehanna minimum — you need the line mass to punch through wind and turn over weighted streamers. A 7-weight is more comfortable for all-day popper fishing. Medium-fast action; tip-flex rods work here, not ultra-stiff. WF6F or WF7F floating line for poppers and shallow streamers; an intermediate sink-tip for deeper runs.

Leaders: 9 ft tapered to 10-15 lb (2-3X) for subsurface; 8 ft to 10 lb for topwater. Fluorocarbon tippet for subsurface; monofilament for poppers (fluoro sinks the popper leader).

Approach and wading strategy

Read the shoal, then work the edges. The shoal itself — the flat, shallow gravel bar — holds fish in early morning and low light. The edge of the shoal (where it drops into the adjacent run) holds fish throughout the day. Start on the shoal, strip a popper or Clouser across the flat before light, then transition to the edge as the sun rises.

Cast upstream and across, retrieve downstream. Smallmouth orient into current just like trout. A fly that swings from upstream to downstream across a seam edge triggers the same reactionary strike as a trout intercepting prey.

Work around rock structure. Individual boulders in the shoal create seams exactly like trout water. The cushion water on the upstream face of a boulder, the scour immediately behind it, and the lateral seam edges — all hold smallmouth in exactly the positions trout would occupy in trout water. The skill transfer is direct.

Access and logistics

Kayak shuttle option: For anglers who want to cover 4-8 miles rather than wade a single access point, a kayak float with a wade fishing stop at target structure is highly effective. Multiple outfitters offer shuttle service on the central section.

Parking and access: Most productive access points require a walk across gravel bars at low summer flows. Drive shuttle-style to find the starting point. PFBC river access areas are mapped on the PA Fish & Boat Commission website.

Regulations: Smallmouth bass season and size limits vary between PA and MD waters. Check current regulations before fishing.

Last updated: 2026-05-01.

Sources cited: PA Fish & Boat Commission — Susquehanna River smallmouth bass, Fly Fisherman Magazine — Susquehanna River smallmouth, Mid-Atlantic Fly Fishing Guide — Susquehanna smallmouth access points, [Bob Clouser — Clouser's Flies (Stackpole Books, 2007)].