Even a little backyard water feature benefits from a real pond liner. While it’s obviously a necessary feature for a million-gallon recreational pond at the heart of a subdivision, liners are also recommended for small ponds built by homeowners. Yet, actually selecting the right material and manufacturer isn’t always easy if you’re not familiar with the geomembrane industry. You don’t need to become an expert in pond design or liners just to make the right choices. BTL Liners is happy to help with expert advice backed by 40 years of industry experience. We’ll guide you to the right pond liner for every residential design, regardless of budget or design constraints.
Retention and Detention Pond Concerns
Liner selection is perhaps most complicated for stormwater ponds. These ponds are commonly found in subdivisions, planned housing developments, and existing neighborhoods that developed flooding issues. Designed to accumulate stormwater runoff from the surrounding area, these ponds are most commonly added in the lowest point of an entire neighborhood. Retention and detention ponds experience the heaviest loads of chemical contamination among other issues that can shorten the lifespan of the liner. It’s recommended that you choose a liner that is both chemical and UV-resistant when building these kinds of ponds. This will ensure the liner isn’t affected by the content of the runoff during changing storm conditions. Shifting cover material, that leaves a part of the liner exposed, is less likely to cause a leak if a UV-resistant liner is selected.
Fish-Safe Liners for Decorative and Recreational Ponds
Fish-safe liners are essential for any pond intended to hold fish, whether the eventual purpose is simply decorative or for recreation. Fish raised in a pond with the wrong liner may not be safe to eat, ruining the fun of a fishing pond. Fish-safe liners are easier to find than you might assume, rarely adding a significant cost to the project over the use of other geomembranes. These liners are also a good choice for recreational ponds designed for swimming and boating since they tend to attract fish populations within the first few years. Fish play a big role in keeping the water clean and healthy, so it’s better to err on the side of caution when choosing a liner material. Don’t just settle for claims of fish safety from the manufacturer or supplier. Check for third-party laboratory verification before risking the health of any fish.
Swimming Pond Design
The liners added to natural swimming ponds will need to be safe for fish and humans alike, meaning it should be free of plasticizing chemicals. It must also be durable enough to withstand the foot traffic of eager guests, ready to jump in. Since these ponds rely on half or more of the pond’s volume being set aside for a bio-filtration area to clean the water, it’s essential to line just certain parts of these water features. A highly flexible liner is essential to create the curves and organic shapes preferred by most homeowners and property designers building natural swimming ponds. Reinforced polyethylene is a great choice because it’s strong, yet thin at the same time for good conformation to a curved surface.
Flexible Liners vs Concrete
It’s a common mistake to assume that concrete or asphalt materials used in some pond designs are intended as impermeable liners. However, neither of these two materials are actually impermeable. Both suffer from porosity and slowly lose water over time to seepage. Coatings are available to make the surfaces impermeable, but they’re hard to apply, costly, and only last a few years before needing replacement. In contrast, flexible geomembranes can last decades before needing replacement. If concrete is recommended by a designer to protect the banks or create a boat dock area, it’s always easy to run flexible liners under the surface to form an impermeable barrier before the physical one.
Which Flexible Liner Material?
40 years ago, pond designers only had a few materials to choose from during the installation process. Today’s ponds benefit from a far wider range of liner materials, making it easier than ever to find just the right fit for the project. However, each material has its own benefits and limitations that make it appropriate for certain situations. Before rushing out to buy the first pond liner you find for a residential project, consider how the most common polymers stack up against each other.
- PVC: Polyvinyl chloride is one of the materials most widely used for pond lining. Unfortunately, it’s far from the best choice for most applications, including residential ponds. It’s usually not fish-safe because it relies on a wide range of chemicals for UV protection and flexibility. Fish kept in PVC ponds tend to grow slowly or succumb to illness. This material is also rarely available in the reinforced style that prevents tearing and cracking over time. Finally, PVC is a poor choice for retention and detention ponds because most liners made from it lack chemical resistance.
- EPDM: Ethylene propylene diene terpolymer is a rubber material that was originally used for roofing. While some companies now market it as a pond lining material, it’s not built with that purpose in mind. Few other materials cause as many leeching issues as this thick, rubber sheeting. It’s also heavy, hard to move, and too thick to conform to the shapes of organic ponds. Leave EPDM for roofing and choose a better liner, even for basic residential pond designs.
- HDPE and LDPE: High density polyethylene and low density polyethylene are both commonly made into durable pond liners. Yet, on their own, each suffers from a range of drawbacks. Both are sensitive to different types of chemicals, while HDPE is stiffer and can be hard to shape into curves and gentle shelves. LDPE is soft and easy to shape, but it can lack durability and longevity. For the best of both materials, try RPE.
- RPE: Reinforced polyethylene is the ideal material for all residential pond designs. It combines the best of both types of polyethylene into one highly flexible, yet durable package. The reinforced design not only extends the life of the liner by reducing wear damage, it also speeds up installation by preventing tearing from roots and sharp rocks in the soil. The material is lighter and thinner than other liners, reducing shipping costs and installation labor alike. Finally, RPE is available in fish-safe and even potable water approved formulations, to ensure there’s a liner safe for every residential use.
It’s true that homeowners aiming to complete very small, personal projects can turn almost anywhere for a pre-cut piece of pond liner. It’s developers and designers working on community scale ponds that generally have to look for custom fabrication for liner materials. However, even homeowners working on residential ponds can benefit from custom fabrication when they’re building a pond to hold a few thousand gallons or more. Custom fabrication involves cutting and sealing seams in the manufacturer’s warehouse, so the work doesn’t have to be done on-site by inexperienced team members. The other steps of installation are relatively easy to learn, but mistakes made during seam sealing often lead to long-term leaking. Custom pond liner fabrication means you receive a liner perfectly built to fit your particular pond design.
Liner selection for residential ponds can easily become overwhelming. With so many products on the market today, it’s no wonder homeowners and developers alike often skip their pond plans to avoid making a choice. Let us, here at BTL Liners, give you advice on the right liner product made from reliable RPE. We’ll collect all the details of the project to ensure we make an accurate recommendation for lining the pond.