Quick Answer: Yes. BioThane® is fully waterproof, not water-resistant. A waterproof dog leash made from BioThane® doesn’t absorb water, so it won’t soak through, swell, rot, or hold odour the way treated nylon or leather can.

What “Waterproof” Actually Means in Dog Gear

The terms waterproof and water-resistant get used interchangeably in dog gear marketing, but they describe fundamentally different things. Water-resistant items will repel the effects of water to a point. After prolonged exposure or enough pressure, water will either soak the item or seep through. A water-resistant leash might handle a quick rain shower or a splash through a puddle, but leave it wet long enough or submerge it, and the material absorbs.

If a material is waterproof, it offers a full protective barrier, designed to handle prolonged and heavy exposure without letting water through. That’s the distinction that matters for working dog gear. A leash that performs in a light drizzle and a leash that performs in a river crossing are not the same thing, even when both are marketed as waterproof.

Most “waterproof” leashes on the market are treated or coated nylon. The treatment adds surface repellency, but the underlying fiber is still porous. Once the treatment degrades or exposure exceeds its threshold, the material performs like ordinary nylon.

How BioThane® Handles Water

BioThane® is not a surface treatment applied to an existing fabric. It’s a heavy-duty polyester webbing sealed inside a waterproof TPU or PVC protective coating that blocks water, dirt, and grease from reaching the internal fabric core, so the coated webbing will not rot, crack, or hold odours.

The key is that the coating is continuous, not a finish applied over an open weave. The tensile strength comes from the polyester webbing inside, but water never reaches it. There’s no pathway in. Water sits on the surface, beads, and wipes off.

This is why BioThane® behaves the same whether it’s dry or soaked. Its weight, flexibility, and grip don’t change. There’s no break-in period and no performance drop after repeated water exposure.

Why This Matters Beyond Rain

Rain is the obvious scenario, but it’s rarely the most demanding one. Real use conditions are more varied and more sustained than a passing shower.

Swimming puts gear in full submersion for extended periods. Mud attaches and dries into fabric, carrying bacteria with it. Snow melt sits in contact with the material for hours on a winter hike. A wet leash left in a vehicle or a gear bag overnight in warm temperatures gives bacteria exactly what it needs to grow.

Nylon can absorb water, which may cause the leash to become heavy, smelly, or prone to mildew if it isn’t properly dried. Damp nylon is more prone to mildew and odour when it’s stored in a warm, enclosed space like a car.

BioThane® doesn’t have that problem because there’s nowhere for moisture to go. The coating gives bacteria, mud, and odour molecules nothing to grip. A rinse after a hard day out is enough, because nothing penetrated in the first place.

Hardware Matters Just as Much as the Material

A fully waterproof strap paired with hardware that corrodes is still a gear failure. Hardware is where moisture damage shows up first, and it’s often where shoppers spend the least time reading the spec.

Common hardware in dog gear is brass, zinc alloy, and stainless steel. The catch with stainless is that the word on its own isn’t one thing. 304 is the general-purpose grade most gear ships with. 316 is the higher grade, distinguished by its molybdenum content, known for excellent corrosion resistance even in harsh marine environments. That molybdenum is what lets it resist pitting, tarnish, and salt-driven corrosion that lower grades and coated finishes don’t hold up to over time.

Zinc alloy and plated finishes develop surface oxidation with repeated wet exposure. That oxidation leaves dark residue that transfers to light-colored or white dog fur, and it pits, which roughens the surface and speeds up further degradation. The clasp may still function, but the finish is gone.

This is why the grade matters, not just the word “stainless.” On load-bearing hardware that sits under tension and takes direct water exposure, clasps and rings, 316 stainless is the standard to look for. Some parts call for a different material by design. Quick-release buckles, carabiners, and similar components are built from other metals because of how they function, not to cut corners. What matters is that the material is chosen for the job the part does, and that anything load-bearing and exposed is built to hold up wet.

Red Flags When Shopping for a Waterproof Dog Leash

Knowing what to ask before buying saves replacing gear that fails in the field.

Ask whether the coating is continuous or surface-applied. A treated finish over an open weave is not the same as a fully sealed coating. Ask what the hardware grade is, specifically. “Stainless” without a grade number is not a guarantee of corrosion resistance. Ask whether the material has a known history of odour retention after wet use. That answer tells you whether the waterproofing is genuine or marketing language.

Watch for vague terminology. Waterproof means completely impervious to water, while water-resistant denotes some level of protection against water. When a brand uses those terms interchangeably, that’s the clearest signal the distinction doesn’t hold in the product.

A leash that is genuinely waterproof will tell you exactly what the material is, exactly what the hardware grade is, and describe the construction rather than just the outcome.

Frequently Asked Questions

Is BioThane® actually waterproof or just water-resistant? BioThane® is fully waterproof. The waterproof TPU or PVC coating blocks water, dirt, and grease from reaching the internal polyester webbing core. There’s no absorption and no water pathway into the material.

Can BioThane® dog leashes be left outside or in the rain permanently? BioThane® won’t absorb water or develop mildew from rain exposure, and the coating itself doesn’t degrade from moisture. The factors to watch over the long term are UV exposure and hardware corrosion, not the strap material.

Does BioThane® get slippery or hard to hold when wet? BioThane® can get slightly slippery when wet, which is why most BioThane® is embossed with a leather-style texture that adds grip. The texture offsets it well, and because the material doesn’t absorb, it never gets waterlogged or heavy in the hand the way a soaked fabric leash does. For long lines or heavy water use, a looped handle gives you a secure hold if the leash gets wet.

Will a waterproof leash still smell after swimming or mud? A genuinely waterproof, non-porous material has nowhere for odour to live. Water and bacteria can’t penetrate the coating, so mud and swim water rinse off rather than soaking in. Odour retention after wet use is usually a sign the material is absorbing, not repelling.

What hardware should I look for on a waterproof dog leash? On load-bearing hardware like clasps and rings, look for 316 stainless steel specifically, since “stainless” on its own is often the lower 304 grade. The molybdenum in 316 gives it corrosion resistance that holds up in wet and salt conditions, where zinc alloy and plated finishes tend to pit, tarnish, and leave residue on light fur. Some parts, like quick-release buckles or carabiners, use other materials by design, so what matters is that each part suits its job and anything under tension is built to hold up wet.