Choosing a liner means considering more than just how well it will handle the initial installation. The liner has the last for decades, especially considering that today’s extra-large landfills are projected to continue producing leachate for up to 10 years. The pond can take another decade to evaporate or drain after that, significantly extending the needed liner lifespan. Using the wrong material, without a warranty to back up the installation, could result in both liner failure and high remediation costs to repair the damage to the surrounding soil and water. Understanding the factors that affect the lifespan of a flexible geomembrane liner will help you assess if a particular product can really live up to its warranty claims or not. In general, you can expect decades of service from reinforced polyethylene liners from BTL Liners with proper installation methods.
Exposed vs Covered Installation
Exposed liners generally do not last as long as those that are covered by thick layers of soil and gravel. Even when you choose a material explicitly designed to withstand exposed installation, the expected lifespan and warranty terms will be a little shorter. This is due to both UV exposure and wear and tear. Foot traffic is much higher on an exposed bank where the workers responsible for dredging the pond and cleaning the pipes are constantly walking. UV exposure slowly makes the flexible liner turn brittle, eventually causing it to crack after many decades of daily sun. For the longest terms of warranty and reliable performance, choose buried installation whenever possible.
Reinforced Material
Reinforced liner materials are much more likely to hold up for multiple decades than non-reinforced designs. The addition of a scrim core adds durability that remains over time, especially if the liner is buried underground rather than installed in an exposed way. Reinforced liners offer better crack and puncture resistance, won’t tear as roots grow under the leachate pond, and are easier to remove when they do finally need replacement or repair.
Slump and Slope
All basins and ponds feature some amount of slope to their embankments, which can make it seem impossible to keep a flexible material in place over them without sliding. Gravity loves to roll the material right down the edge of one bank while the other is being covered. Putting down sandbags can help until the material is covered by water, but the weight of the water alone may not keep the liner from slumping or shifting over time; especially if it’s slippery and the banks are steep. Reinforced liners have the stiffness to stay firmly adhered to a slope without punctures or anchoring equipment that could cause leaks in the material.
Total Weight
The amount of weight pressing down on the liner also affects how long it can last before it becomes deformed or splits under the pressure. This is particularly a problem if the ground under the leachate pond isn’t properly graded and prepared. Sandy pockets of soil or buried tree stumps can break down over time and create voids under the liner. As the weight of the water presses down, the liner can’t withstand the pressure and ruptures. The greater the volume of the pond and the deeper its depth, the tougher the liner needs to be to last 20 years or more.
Soil Preparation and Underlayment
Careful soil preparation goes a long way in extending the life of a liner. If you leave roots, rocks, and uneven surfaces over the area where you plan to install the liner, you’re not likely to get as good of results. Take the time to clear out and properly grade the soil and consider an underlayment to protect against rips and tears that shorten the lifespan of even the toughest liners.
Turn to BTL Liners for materials that can handle everything leachate ponds throw at them. Our tough RPE liners can be installed over steep slopes and won’t become ruined by some sun exposure. Choose our ArmorPro line for tough industrial pond liners that keep leachate right where you want it.
