Mitigating evaporation

Chris EdwardsJanuary 22, 2024, 7:53 amDecember 15, 2023

Evaporation is a major cause of water loss from dams and reservoirs, but there is a cost-effective way to reduce these losses.

Australians are familiar with the challenges associated with evaporation. The hot climate sees our dams and reservoirs lose a significant amount of water quickly. The El Nino weather phenomenon worries water operators as states rely on their storage capacity for substantial amounts of potable water.

What can water operators and reservoir managers do to minimise the evaporative losses from the sun?

This is where Aquatain Products steps in. It represents a group of experts who develop liquids that spread across water’s surface, forming a thin film. Aquatain Products’ products are based on similar principles but have very different applications. Each is aimed at a specific problem facing the world today.

Evaporation control

Water shortages are looming as one of the world’s major problems in the 21^st Century, with many countries experiencing prolonged low rainfall or drought conditions.

Aquatain Products has developed a product called WaterGuard GOLD. It is an Australian-made, silicone-based liquid that spreads across the dam’s surface, effectively placing a ‘liquid lid’ on the surface.

“The principle of our products is simple, but the impact can be huge,” said Danny Bryan, Special Projects Consultant with Aquatain Products. “Trials have shown evaporation reductions of 50 per cent or more.”

The table shows a few examples of losses from dams of various sizes based on an average daily evaporation rate of 12 mm. This is a typical figure, but it can be much higher in many parts of Australia during summer.

Surface Area of Dam	Evaporation Losses (Litres)
Surface Area of Dam	Daily	Weekly
500 sq m	6,000	42,000
1,000 sq m	12,000	84,000
5,000 sq m	60,000	420,000
10,000 sq m (1 ha)	120,000	840,000

“A one-hectare dam can lose more than 800,000 litres of valuable water each week,” he said. “Evaporation is really a silent assassin, as you can stand beside a dam all day and not realise that the water is disappearing in front of you.”

WaterGuard GOLD is easy to apply. For most dams, it can be poured on from the edge, and it will self-spread to cover the surface. It can be used directly from a boat or barge for larger storage facilities.

The product is economical to use. For example, three litres will protect 1,000 square metres of water surface in a harsh environment for up to three weeks. A lower rate can be used in less severe conditions.

WaterGuard GOLD is produced from polymers that are highly impermeable to gases, including water vapour. These polymers repel each other strongly when they come in contact with the water, resulting in a robust spreading action across the surface.

Who are Aquatain Products?

Aquatain Products is an Australian company pioneering its unique liquid technologies since 2006. These technologies have focused on developing products that form a thin film on the water’s surface.

In addition to WaterGuard GOLD for evaporation control, the company has another flagship product called Aquatain AMF for mosquito control. It is effective in breaking the mosquito breeding cycle and is approved for sale in about 70 countries.

Aquatain AMF has been prequalified by the World Health Organization, which ensures users that it has been assessed for its efficacy, safety, and quality. Aquatain Products offers a range of Aquatain AMF products for different circumstances. This is not limited to liquid films, as it offers both blocks and drops for different applications.

Aquatain Products also has an oil spill collector, with a product called Gladiator. It is a unique silicone-based liquid that spreads across the water’s surface. Gladiator pushes the oil and consolidates it in one place on the surface. Its low surface tension translates to strong spreading pressure. Gladiator also features a stable viscosity across a wide temperature range.

For more information, visit www.aquatain.com.