Fly Fishing

What Stands Out

• A genuinely waterproof main compartment. The fully waterproof, self-healing TRU Zip closure is the defining feature, protecting the primary storage area against heavy rain, spray, and accidental immersion when properly closed.
• Heavy-duty 900D construction. The TPU-coated NewStream fabric creates a substantial, abrasion-resistant exterior suited to gravel bars, boat floors, wet vegetation, and frequent handling.
• 28L of practical fishing capacity. Enough space for spare insulation, a rain shell, lunch, fly boxes, electronics, and other essentials without moving into oversized expedition-pack territory.
• A more substantial carrying system. Foam shoulder straps, a molded back panel, hip belt, and adjustable, removable lumbar support strap make this more than a waterproof equipment sack with shoulder straps.
• Separate quick-access storage. The front pocket uses a water-resistant zipper, providing convenient storage for frequently used items that don’t require the protection of the waterproof main compartment.
• Fishing-specific attachment options. Hypalon shoulder-strap points, coated webbing daisy chains, a D-ring, and four-way back-panel attachments provide places to configure essential equipment.
• Rod-carrying flexibility out of the box. One set of Lariat Gear Straps is included, giving anglers a practical way to secure a rod tube without immediately purchasing another attachment.

In The Field

The reason I want a waterproof backpack isn’t that I enjoy fishing in terrible weather. It’s that some of the best fishing days in Washington involve conditions that would make an ordinary daypack a liability. A November steelhead float on the Olympic Peninsula, a cold morning on the Sauk, or an afternoon casting from a Puget Sound beach can involve persistent rain, spray, wet gravel, and very few opportunities to dry anything out. The Thunderhead Submersible Backpack is built for that environment — a substantial 28L fishing backpack designed around a waterproof main compartment, not a minimalist pack with a rain cover pretending to be waterproof.

On a Skagit or Sauk drift-boat day, I want a backpack I can set on the floor without thinking about every puddle beneath it. The Thunderhead’s 900D TPU-coated exterior feels appropriate for that job. The material is substantial rather than soft and floppy, which helps explain both the pack’s rugged character and its weight — the sort of construction I’d choose for repeated contact with wet boat surfaces, gravel, and brush.

The waterproof protection comes from the main compartment’s TRU Zip closure. When properly closed and maintained, it provides a level of protection that a rain cover or ordinary coated zipper doesn’t. That matters most when a pack takes spray in a rapid or slips into the river during a hurried landing. It doesn’t make the contents invincible — I’d still put irreplaceable electronics in secondary protection — but it changes how confidently I handle the pack around water.

The biggest adjustment for someone coming from a normal daypack is the zipper. A conventional zipper is designed primarily for convenience; the Thunderhead’s TRU Zip is different because the closure is also the waterproof seal. It requires deliberate operation, especially around the pack’s relatively stiff upper opening — not difficult, but less casual than opening a lightweight hiking backpack. The clamshell-style top is another trade-off. The heavy fabric and closure can feel stiff when you’re trying to reach inside quickly, so if I’m repeatedly changing flies or grabbing tippet, I treat the main compartment as protected storage rather than opening it every few minutes.

The self-healing feature is useful to understand. If the seal separates behind the slider, Fishpond’s guidance is to back the slider up and close it again. It doesn’t mean the zipper repairs physical damage, and it doesn’t eliminate the need for maintenance. Regular cleaning and lubrication are normal parts of TRU Zip ownership. Sand, grit, and river sediment aren’t things I’d want sitting in the sealing surfaces, particularly after fishing silty water or a windy beach. Before a long float, I’d inspect the zipper, clean the sealing surfaces, and verify that the closure is fully seated.

It’s easy to misunderstand what a waterproof backpack actually protects. The Thunderhead has a fully waterproof main compartment, but the front pocket uses a water-resistant zipper — different levels of protection. I’d use the front pocket for a leader wallet, gloves, or small accessories that can tolerate some moisture, not an unprotected phone, camera battery, or vehicle key fob before wading deep or leaving the bag in heavy spray. On the Yakima, where I’m often stopping to change leaders between runs, that quick-access pocket keeps me from opening the waterproof compartment unnecessarily.

At 3.05 lb empty, the Thunderhead is not a particularly light daypack. Add a camera, spare clothing, lunch, water, and fishing gear, and you’re carrying a meaningful load before reaching the river. The weight is the most obvious compromise against an ordinary 28L hiking pack. What makes it more practical than a basic waterproof dry bag is its harness: foam shoulder straps, a molded back panel, a hip belt, and an adjustable, removable lumbar support strap. Those features matter on Olympic Peninsula approaches with slippery cobbles and wet brush. I’d still choose a lighter pack for a long, dry summer hike; the Thunderhead earns its place in sustained rain, deep wading, or frequent water exposure.

One limitation of a large waterproof compartment is that it doesn’t automatically provide great organization. The Thunderhead includes a removable zippered interior pocket for separating smaller items; beyond that, I organize with my own packing system. Spare insulation and a rain shell go toward the bottom, lunch and less-used equipment above them, and fly boxes where I can retrieve them without emptying the bag. For a camera, I’d use a protective padded insert — waterproofing and cushioning are two different things. There’s also a practical reason not to overload the pack: a tightly packed compartment makes the stiff opening harder to manage and the zipper harder to seat. Fishpond lists the capacity as 28L, although its printed specification also says 1,648 cubic inches, which is closer to 27L. I would use the manufacturer’s 28L designation when comparing pack sizes.

The Thunderhead has several useful attachment options — Hypalon points on the shoulder straps, a coated webbing daisy chain, a D-ring, and four-way attachments on the back panel. A two-way radio or GPS unit can sit on the shoulder straps where it remains accessible, and other compatible accessories can mount externally without taking main storage. I’d still avoid turning the outside into a collection of dangling tools; loose equipment catches on branches, fly line, and boat hardware. For anglers who already use a Fishpond Thunderhead Submersible Chest Pack, the backpack is designed to work with that system — frequently used fishing gear in front, clothing, food, and valuables in the larger pack.

One welcome inclusion is the set of Lariat Gear Straps, useful when carrying a rod tube during an approach or between fishing locations. I’d secure the tube close to the pack rather than allowing it to swing outward in brush. The straps are included; the rod tube and other accessories are separate purchases. On a long Olympic Peninsula day, the Thunderhead works well as the main equipment bag: rod tube for the hike, dry layers and electronics inside, then the pack in the boat or on a gravel bar while fishing. The same arrangement makes sense for Puget Sound beaches, where sideways rain and salt spray can turn an otherwise pleasant outing into a test of every zipper and seam. After saltwater exposure, I’d rinse the exterior and clean the closure according to Fishpond’s care guidance rather than leave salt crystals or sand around the TRU Zip.

The Thunderhead isn’t the bag I’d choose for every fishing trip. On a dry summer evening at the Yakima, a lighter pack might be more pleasant. But for the kind of wet, unpredictable fishing that defines much of the Pacific Northwest, the added protection has a clear purpose.

Technical Specifications

Final Thoughts

The Fishpond Thunderhead Submersible Backpack is a specialized piece of fishing equipment, and I think it makes the most sense when evaluated that way.

If you’re comparing it strictly against conventional 28L daypacks, the numbers aren’t especially flattering. It’s heavier, more expensive, and less convenient to open. The TRU Zip needs regular attention, and the front pocket doesn’t provide the same waterproof protection as the main compartment.

But those comparisons miss the reason I’d carry it.

On a cold steelhead float, I want to be able to put my pack on the wet floor of a drift boat without worrying about the spare insulation or camera inside. When I’m wading a deep run on the Sauk, I want confidence that a brief dunking won’t automatically end my day. On a Puget Sound beach, I want a bag that can sit through hours of wind-driven rain while I concentrate on fishing.

The Thunderhead is built around those situations.

I particularly appreciate that Fishpond hasn’t treated the backpack as merely a sealed container. The molded back panel, shoulder straps, hip belt, attachment points, and included rod-carrying straps make it a more complete fishing system.

The Eco Yucca colorway is understated, the 28L capacity is useful for full-day outings, and the waterproof main compartment is the feature that ultimately justifies carrying the extra weight.

I’d recommend it most strongly to anglers who regularly fish from boats, wade substantial rivers, or spend long hours in exposed coastal conditions. For occasional fair-weather trips, the price and weight are harder to justify.

It’s not the lightest or most convenient backpack I’d take fishing. It’s the one I’d choose when keeping my equipment dry matters more than either of those things.