Secure water for your crops.
Covex® is a hexagonal floating cover that seals the water-air interface. It cuts evaporation by up to 97%, blocks the sunlight that feeds algae, and removes the open water that attracts birds. The water you paid to pump, capture or buy stays in your reservoir until your crops need it.
It all starts at the water-air interface.
Wherever your stored irrigation water meets the air, the same three things happen, regardless of what you grow: water evaporates, light feeds algae, and the open surface draws in birds. In arid regions a reservoir can lose up to 3,200 mm of water column per year to evaporation alone.
Evaporation
Water you pumped, captured or were allocated disappears into the air: up to 3.2 m³ per m² of exposed surface per year. On a one-hectare reservoir that can exceed 30,000 m³ per season, water that never reaches a single plant.
Algae and clogged irrigation
Sunlight on the open surface fuels photosynthesis. Algae blooms clog drip emitters and filters, force backflushing and chemical treatment, and degrade the quality of fertigation water.
Birds and water quality
The open water surface attracts birds whose droppings introduce pathogens and nutrients into water destined for food crops, a recurring finding in food safety audits and a constant load on filtration.
How many m³ does your reservoir lose each irrigation season? Tell us where it is and its surface area and we run the calculation.
Calculate my seasonal lossA cover that self-installs and self-adjusts.
The hexagonal HDPE modules float, interlock, and settle on their own to the reservoir level. They require no structure, anchoring, or maintenance. Each unit carries water ballast that keeps it in place even in extreme wind.
Less evaporation
The physical barrier of the hexagons cuts the mass exchange between water and air. 98% coverage of the liquid surface.
Stops algae growth
By blocking light, it inhibits photosynthesis in the stored water, protecting drip emitters, filters and fertigation quality.
Virtually eliminates the open water surface
With no visible reflective surface, birds are far less likely to detect the reservoir, keeping droppings and pathogens out of irrigation water.
Delays freezing on frost nights
The air chamber inside each module acts as an insulating barrier. Water stays liquid and pumpable longer, exactly when frost-control sprinklers need it.
See a Covex® cover working on a real reservoir. One minute, then the numbers for yours.
The same cover, the value that matters to you.
The physics of the water-air interface is universal, but the priority changes with the crop and the climate. Find your operation below.
Vineyards & Orchards
- Water security through peak demand: the m³ you store in winter and spring is still there when the crop needs it most, instead of evaporating through summer.
- Algae control protects drip irrigation: blocking light inhibits photosynthesis, which means fewer clogged emitters, fewer filter backflushes and less chemical treatment.
- Shaded water: blocking 98% of solar radiation cuts the light that drives algae and limits solar heating of the water at peak hours.
- Bird exclusion keeps droppings and pathogens out of water headed for food crops, supporting food safety audits.
Irrigation Communities
- At scale, evaporation is an allocation problem: in arid climates a shared 5-hectare reservoir can lose over 150,000 m³ per year, water every member already paid for.
- Modular deployment with no civil works: no structure, no anchoring, no need to drain the reservoir. The cover is operational the day it is launched.
- Water-efficiency funding: floating covers can qualify under irrigation modernization and water-saving subsidy programs in several jurisdictions.
- Self-adjusting to level: the hexagons follow the water as the reservoir drains through the season, with no maintenance crew required.
Greenhouses & Intensive Horticulture
- Algae control at the source: stored rainwater and recirculated water stay dark, reducing the biofilm and algae load on fertigation systems.
- Less treatment cost: blocking light reduces the need for algaecides and filtration downstream, instead of fighting algae after they bloom.
- Frost protection readiness: on freezing nights the cover delays the freezing point by 60%, keeping water liquid and pumpable for sprinkler frost control at dawn.
- Bird and debris exclusion over water destined for high-value crops.
Cooler at peak sun, liquid water on frost nights.
Covex® slows heat exchange between the water and the air, by day and by night. Both effects work directly for agriculture.
It slows temperature changes in both directions.
The cover intercepts sunlight before it reaches the water and slows heat exchange with the air. Water warms up later in the day, so at peak sun it runs about 4°C cooler than uncovered water, and at night it loses heat more slowly. That slower cooling is exactly what keeps water liquid on frost nights.
By night, it retains heat and delays freezing.
On frost nights, frost-control sprinklers only work if the stored water is still liquid and pumpable when temperatures bottom out at dawn. Against a -5°C environment, Covex® keeps the water up to 5.2°C warmer than the uncovered surface during the first hours of the night.
The effect is decisive where there is freezing risk: uncovered water reaches 0°C at 7.5 hours, while under Covex® the freezing point is delayed to 12 hours, 60% more time. Intake pipes and pumps stay protected as well.
Cleaner irrigation water, by design.
Food safety standards increasingly look at the quality of irrigation water, and stored open water is the weakest link: sunlight feeds algae, and the open surface invites birds whose droppings carry pathogens and nutrients. Covex® provides a continuous physical barrier that removes both drivers at the source, an auditable measure that works 24 hours a day with no active devices.
No open water, no birds
By covering 98% of the surface, birds are unlikely to perceive a body of water to land on or drink from. The deterrence is structural and does not rely on cannons, nets or lasers.
Algae stopped before they bloom
Without light there is no photosynthesis. Blocking 98% of solar radiation inhibits algae growth by 95%, protecting drip emitters and filters and reducing the need for algaecides and chlorination downstream.
Independent technical validation
The system has evaporation and thermal-behavior validation through TRNSYS, ANSYS Fluent and CFD modeling, with academic institutions and water research centers.
Zero maintenance, automatic adjustment
The hexagons rearrange themselves as the level changes through the irrigation season. There is no structure to inspect and no anchors to fail.
Preparing a food safety audit? Ask for the technical documentation describing Covex® as a passive barrier against birds and algae.
Request the documentationData measured on site, not catalog promises.
From premium wine estates to commercial nurseries and orchards.
Want to hear it from a grower already using Covex®? Ask for a reference site with a comparable crop and climate.
Ask for a reference siteLet's do the numbers.
Tell us about your reservoir and we will provide an estimate of evaporation, recovered water, chemical and labor savings, and payback for your site.
Thank you for reaching out. A Covex® specialist will review your request and get back to you.
Why floating covers are becoming standard practice in irrigation storage.
A technical overview of evaporation losses, algae control, and water security in agricultural reservoirs: Floating covers for agricultural water protection