With so many potential benefits for aquaculture projects from geomembrane liners alone, it’s surprising that so many new systems are still built without proper lining. Many entrepreneurs start out with raw in-ground ponds and plan to install liners later if the business takes off. Of course, there’s never enough time later to actually implement these desired upgrades. Starting off on the right foot, with geomembranes installed from the start, will give the project a much better chance of success. From reducing water costs to stabilizing water quality, you’ll find it much easier to maintain the system with the help of a liner. Here’s a whole list of the best uses of geomembranes in the aquaculture world.
Lining In-Ground Ponds
In-ground ponds of all sizes are the primary uses for geomembranes across the entire aquaculture industry. Without liners, these ponds are usually fairly to highly inefficient; even if lined with clay or concrete. Since ponds used for aquaculture tend to be relatively shallow and offer a large surface area instead. This translates into a lot of soil/water contact between the two surfaces. Without a liner, there’s a lot of potential for seepage and water loss. Lining in-ground ponds is the best way to stabilize water quality and quantity for reliable fish and plant production.
Improving Above-Ground Tanks
Don’t fall for the misconception that pre-formed fiberglass and plastic tanks are incompatible with flexible liners. These tanks are often improved with the addition of either a liner inside the vessel or installed underneath the exterior as a form of secondary containment. Custom built concrete and steel tanks definitely need a liner since these materials are not water impermeable on their own. If you have older tanks you want to reuse, a liner can help save them if they’re still stable and only lightly leaking. Finally, liners also protect metal aquaculture tanks from corrosion and chemical reactions to compounds in the water.
Creating Watertight Raceways
Raceways are some of the most popular ways to raise fish since they’re designed to keep water flowing and fresh at all times, even in recirculating systems. Long and narrow trenches or ponds are built that tap into a steady water source. The shape of the pond encourages a strong and uninterrupted flow, which is necessary for the healthy and rapid growth of many species like trout. The earliest raceways were simple trenches dug near a river so part of the flow could be diverted through them. This system is still widely used today for fish farms and hatcheries raising species that are too sensitive to use recirculated water on. However, raceways also work perfectly fine when used with recirculating systems since the reused water is easily pumped back to the beginning of the system.
Regardless of the use, raceways need to be lined and sealed. Their narrow and long shape doesn’t make this an easy task, especially in the tight corners. Flexible geomembranes are the best solution for lining any raceways and similarly shaped connecting channels and trenches. This material can bend and conform to the precise shape of your raceway, whatever that may be.
Sealing Concrete Basins and Structures
Concrete tanks, retaining walls, and basins are widely used in commercial aquaculture. Few other materials can compare to concrete when it comes to the combination of durability, strength, and flexibility in shaping and forming. However, there’s a common misconception in many industries that concrete itself is impermeable in some way. While concrete can create a basic barrier to prevent erosion or soil collapse, it’s actually porous when left raw and uncovered. Concrete has smaller pores than soil, so it will still seep out less water than bare soil. Yet, you’ll still lose too much valuable water to make concrete the only reasonable liner for an aquaculture system. Pairing a layer of impermeable geomembrane with your concrete is the best way to control leaks and water loss.
Protecting Channels and Trenches
When a large amount of water needs to be directed from one part of the aquaculture system to the next, designers often implement in-ground channels and trenches instead of pipes to carry it. Yet, the narrow width of the channel and the high velocity of water flowing through it increases the risk of erosion and destabilization that eventually leads to collapse. Many trenches and channels are only lined with concrete or gravel; two materials that aren’t impermeable. In order to ensure the needed water reaches its destination rather than seeping away, use the same geomembrane for the entire water holding system.
Containing Runoff from Processing Areas
In addition to the active growing areas used in aquaculture, processing areas for preparing fish and crops for purchase and shipping need appropriate lining too. These areas produce highly concentrated runoff that can have an even greater effect on the surrounding environment than the water in the tanks or ponds. A simple in-ground basin, with slightly raised edges, is often enough to capture wastewater generated during cleaning, processing, and packaging and will direct it to the appropriate drain or holding tank.
Holding Wastewater and Freshwater Supplies
There’s also the need to store both wastewater and freshwater for any large aquaculture systems. Most tanks and other above-ground structures simply can’t offer the same bulk volume provided by an in-ground pond. A fish farm or hydroponic greenhouse can generate hundreds of gallons of wastewater per day; especially in an open system that doesn’t recirculate. This wastewater is best processed to reduce ammonia and settle out particles before it’s released or reused anywhere else. Large ponds with plenty of surface area help this settling process go much more smoothly and quickly.
Mimicking Natural Habitats
Finally, many aquaculture enthusiasts are interested in increasing fish growth by building a natural habitat. This often includes some amount of soil or sand used at the bottom to grow a living ecosystem that stabilizes the water quality and provides a source of food for small fish. You can still use a liner and get water quality control and seepage protection while building natural ponds. Simply add the desired substrate on top of the liner to create your muddy or planted bottom. The roots of most aquaculture water plants won’t penetrate the liner, preventing leaks from occurring over time in these naturalized ponds.
There are so many more opportunities for putting geomembranes to good use in aquaculture that weren’t covered here. Wondering if your idea will work well with a professional geomembrane liner? Talk to our specialists here at BTL Liners and we’ll help you work out the details and explain the many benefits of installing a quality liner for your project.
