Custom designed to fit all shapes and sizes of lagoons, basins or tanks, LET's modular insulated covers are easy to install and adapt to environmental factors, ensuring consistent effluent results.

The high-quality, custom-engineered LemTec™ Modular Insulated Cover System from LET is a multifunctional solution that can be used for custom wastewater treatment processes. Providing maximum efficacy while also resolving a wide range of issues this stand-alone solution is great for specific wastewater treatment objectives. The proven LET technology is comprised of durable insulated geomembrane panels which maintain their rigidity and strength, requiring minimal maintenance over its long lifespan. 



The insulated cover system can be easily retrofit to an existing tank, added as an upgrade to an existing pond, or designed into an LET biological treatment process throughout North America. This innovative LET technology creates a floating protective layer that completely covers liquid in any basin or pond as a key process component of aerobic, anaerobic and partial mix facultative wastewater treatment lagoons. LET’s modular covers are also effective when tailored for use in a wide variety of applications across industries and niche markets including food processing, agriculture, airports, breweries, chemical plants and many more.  The system is pre-fabricated to each of our customer’s unique specifications, ensuring that their objectives are met efficiently and cost-effectively. 


""Lemna's cover and staff have provided performance as promised. Anytime we've had questions related to technical support, LET has been prompt in their response. I can safely state that maintenance on our cover has been virtually non-existent, and I highly recommend LET for anyone considering them for a cover or liner."

~ R. L. Minnesota

LET Client

Related Case Studies


LemTecTM Innovative Cover Solutions Broc

LemTech Innovative Cover Solutions  - Brochure

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Lemna Case Study

LemTec Modular Insulated Cover System.

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Each LET wastewater treatment process and technology, including our LemTec™ Modular Insulated Cover System, is custom designed with our Advanced Integrated Lagoon Technologies (AILT) approach. The AILT approach allows us to integrate cutting edge technologies, such as our modular insulated covers, in combination with over 30 years’ proven experience to deliver guaranteed results that meet each of our clients’ unique needs.

Premier Cover Technology Proven to Improve Process Performance

When LET modular cover technologies are integrated into the design of an LET biological wastewater treatment process, it plays a key role in helping to ensure proper nutrient removal takes place and effluent limits are met. The cover system results in an increased kinetic reaction rate, extending the detention time needed for BOD removal, which significantly expands the lagoon’s treatment capacity with increased efficiency. The LET modular cover is insulated to ensure that optimal treatment temperatures are maintained year-round, allowing for consistent, successful treatment in locales with extreme temperature fluctuations that would impede the process. 

Modular Cover System

Hazard Mitigation

Innovative Solutions for Municipal and Industrial Clients: LET Cover System

Modular covers from LET also deliver solutions in a wide range of other applications in addition to the biological treatment of wastewater. Protecting the ecosystem from toxic byproducts and waste, eliminating nuisance odors to avoid complaints, and containing water to avoid evaporation in areas where the vital resource is scarce are just a few examples of the varied objectives that LET cover system successfully addresses. With the innovative LemTec™ Modular Insulated Cover System, LET is able to meet the wide-ranging needs of our customers.


LET is committed to continuously advancing wastewater treatment processes and technologies, including the LemTec™ Modular Insulated Cover System. We do this by continuously improving and expanding upon our treatment designs and service offerings. Our “Circle of Innovation” philosophy ensures that the needs of our clients are met efficiently, effectively and cost-consciously as we work together with our municipal and industrial clients, protecting water resources now and for future generations.