Clean vs Wastewater Cover Requirements

While there are dozens of potential, unique uses for floating covers made from geomembranes like RPE, most of them can be easily sorted into the categories of fresh and wastewater storage. While both types of liquid require some similar handling considerations, they also vary greatly in their demands from the cover materials. Using a cover designed for potable water use on a caustic mixture of wastewater products may result in disappointment if the material is not up to the challenge. Discover what makes clean and wastewater differ so much and how to match these differences to the right floating cover product.

Control of Incoming Water

The source of incoming water matters the most when it comes to clean water storage. Rainfall that lands directly in the pond or tank may not matter much unless there’s a risk of acid rain or similar pollution problems. Runoff that travels over the surface, even just over the banks of the pond, is another issue entirely. It tends to carry along bacteria, dirt, debris, chemical residues, and other problematic ingredients as it mixes in with the water supply. In a system designed for storing wastewater, this is less of an issue. However, other risks arise from flooding caused by too much rain overflowing the system. While both clean and wastewater require the control of incoming water, it’s for different reasons.

Flooding and Overflow Risks

Another component to controlling the addition of water, is the particular risk of flooding depending on the liquid. Wastewater is often thought of as posing a much higher risk than clean water, and that’s true when it comes to long-term health effects and environmental damage. Since potable water storage units are often built near residential or commercial areas, the risk of flooding from these structures is often structural instead. The cost of repairing or replacing lost homes and businesses often far outweighs the costs of remediation after a wastewater loss or spill. Proper covers prevent both flooding risks, especially when combined with emergency drainage equipment.

Contamination Issues and Discharge Options

Wastewater is already considered contaminated, so it’s rarely an issue if it receives runoff with more bacteria or chemical residue mixed in. Unless there’s a chance of a dangerous reaction, contamination isn’t a concern in those cases. The opposite is true for potable and freshwater storage. Municipalities often spend thousands of dollars per year on re-treatment of clean water that becomes contaminated before it reaches the final users. Covers are therefore more important for fresh water rather than waste products in this case. When considering discharge options, the accelerated speed of water treatment produced by insulated liners opens you up for faster and more affordable release of wastewater. Discharge is rarely an issue with fresh water supplies.

Chemical Resistance

Fresh water supplies are often considered easier to cover than wastewater ponds because they pose less of a chance of chemical reaction. The opposite can actually become true when large amounts of chlorine are needed to sanitize and stabilize potable water for long-term storage. Chlorine is particularly damaging to many materials chosen for rigid and floating covers. Yet, don’t underestimate the mixtures of chemicals found in wastewater products that can corrode or react with the cover material. Both fresh and wastewater projects require careful chemical resistance consideration due to the mixed risks of reactions.

UV Exposure

Both waste and freshwater ponds and tanks are exposed to damaging UV rays from the sun. The amount of sun exposure is determined by the shape, size, and height of the water storage structure. Taller tanks and ponds, with larger surface areas, expose the liner to more light than those located at ground level and with smaller surfaces. Regardless of the installation requirements, it’s possible to choose covers with higher UV resistance to ensure the material doesn’t break down prematurely just because it’s installed over the surface of the water.

Animal and Human Access Risk

Much like with chemical resistance, there’s also a misconception that fresh water supplies are inherently less risky to humans and animals than wastewater ponds. However, potable water ponds and tanks still pose a sizable drowning or fall risk to anyone wandering along their edges. Humans, in particular, may think that the drinking quality of water makes it an ideal place to swim. These activities put them at risk while contaminating the water supply. Animals drinking or swimming in the water also introduce bacteria and viruses. Floating covers protect the water from guests and guests from the water. The risk from wastewater is primarily to the human or animal and not to the water supply itself. This is still best mediated with a secure floating cover that precludes access to the surface from curious parties.

Does your particular pond or lagoon need a cover as soon as possible? Contact us today at BTL Liners to find the right floating cover that matches your current liner material.

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Using a two-color technology, ArmorCover maximizes your protection from the elements. Whether you're needing a greenhouse light deprivation cover, a sports field cover or a hay pile cover, ArmorCover is the best and most versatile solution on the market for all of your cover projects.

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