Durable and flexible liners made from a high-quality polymer work best for groundwater storage lagoons and ponds of all kinds. No matter what exact mix of groundwater and salt, minerals, or processing chemicals you’re looking to store, you can find a geomembrane capable of withstanding its corrosive or acidic characteristics. Liner selection and installation is essential to any pond project, but it’s especially important when storing a potentially hazardous mix of chemicals. Make sure your new lagoons and ponds will protect the existing groundwater supply with these tips for liner selection.
Choosing a Material
There are dozens of specific polymer formulas and combinations available on the market today. Yet, not all flexible pond and lagoon liners offer the same benefits and features. While some materials may work well enough for backyard ponds, they’re not durable enough for commercial, groundwater storage. Other materials aren’t chemical resistant enough to handle wastewater.
The most common options for pond liner materials include:
- PVC (polyvinyl chloride)
- HDPE (high density polyethylene)
- RPE (reinforced polyethylene)
- LDPE (low density polyethylene)
- EPDM (ethylene propylene diene terpolymer)
When designing and building groundwater storage lagoons, multi-layered RPE is generally the best choice. PVC materials are widely available, but they lack the chemical and UV resistance of multi-layered RPE. EPDM is chemical resistant and durable, in addition to being heavy and relatively stiff for difficult installation. Multi-layered RPE is thinner than LDPE while offering the same tear resistance and durability. If necessary, it can handle exposed installation with a lifespan of 20 years or more. Choose a reinforced liner, since the embedded mesh reinforcement adds even more tear and leak resistance for essential lagoon installations.
Single and Double Liners
Many groundwater storage lagoons require a double liner system, with gravel or other porous materials holding a gap open between the two layers. This allows for leaks that form in the initial liner layer to become trapped by the second liner. The second layer of material is either the same liner as above, or a non-woven geomembrane. If the groundwater being stored in the lagoons is highly contaminated, double liners are generally required by local and federal level environmental agencies. Single liner systems are usually sufficient for ponds storing fresh groundwater with low or absent levels of contaminants. The seepage and leaks from these ponds are less impactful on the environment, but single layers of flexible liner material are still used to prevent major losses of useful water.
Sump pumps are usually installed on double liner lagoons to remove any water that leaks between the two liners. These pumps also act a warning system, to notify you of any leaks, since they shouldn’t run unless there’s a problem. The sump pumps are usually inserted through at least one layer of the liner, requiring thorough sealing around the intrusions, to prevent leaks that the pumps won’t detect. Make sure the flexible liner you choose is easy to seal around intrusions if you’re designing a double liner lagoon.
Flexible liners made from multi-layered RPE can provide decades of reliable lagoon performance, regardless of whether they’re installed in a single- or double-layer system. If you’re looking for a groundwater lagoon liner, that requires minimal maintenance while offering chemical and UV resistance, check out ArmorPro from BTL Liners.