Using Dam Covers to reduce Evaporation

Have you heard about safe water-covers also known as dam covers? They are used in areas where dams and other large storages of water are the main sources of clean drinking water. In South East Queensland, they are used to reduce the loss of water into the atmosphere (evaporation).

The amount lost in a single year is equal to a day’s consumption. Besides, the growing population of those living in Australia shows that there’s a need to find new ways of preventing such huge losses of water. Take a look!

Methods of Reducing Loss of Water into the Atmosphere

Here, we will talk about two ways of reducing the loss of water into the atmosphere. Their use has been tested and reviewed by different scholars. They are:

1.    Using Suspended Dam Covers

It’s easy to identify these sheets because of their weight and long-lasting nature. They are also made from either a shaded screen full of little holes or a thick plastic. When installing, place them from left to right on the water surface using steel wires or poles for support.

They are known for preventing sun rays from hitting the water surface. This causes a decrease in the thermal energy getting into the dam or pond. The end result is a reduction in water temperature and any chance of it changing to gas. They can even reduce water vapor pressure by controlling wind force.

2.    Use of Floating or Modular Dam Covers

To stop the changing of water from liquid to gas, the use of flat sheets or modular dam covers is another good method. They block sun rays and prevent the entry of vapor from all directions. Now, the difference between them and suspended sheets is that they are just supported by the water. However, for larger dams, you’ll need to use stronger supportive systems.

Another difference between the two is that floating dam covers cannot survive the effects of strong winds. That’s why they are used in small water storage systems. Tests on larger sources are still being carried out.

Are these dam covers good enough? We need to point out that floating covers don’t fully cover the surface of water. This allows vapor to escape through the few available spaces. It also means that there’s lesser use of energy, and winds can still blow away the moist air.

We’sve also discovered that these covers will only allow small amounts of oxygen to get into the water compared to suspended sheets. This is because of the open spaces in the floating structures. Other factors that affect their use include their design, construction materials, and shape.

Types of Dam Covers You Can Get in Today’s Market!

In Australia, there are four key types of floating and suspended covers that are easily available and simple to use. They include:

Brands of floating dam covers available in Australia include ‘E-VapCap’ and ‘AquaCap’. For suspended sheets, these are ‘SuperSpan’ and ‘NetPro’. All of them are dense and don’t allow entry of liquid or solid substances.

How to Reduce Release of Vapor in Dams

There are a lot of studies explaining the different ways of reducing the release of water into the atmosphere. Many of them show that using floating and suspended covers is the best way of preventing the escape of vapor. They explain how they decrease strong winds and reduce the effects of solar radiation.

These studies show that dam covers such as ‘AquaCap’, have a 60% usage rate. They not only reduce water temperature but also do an excellent job of killing different types of seaweeds. Other covers from the ‘E-VapCap’ company reduce the rate of evaporation by 95%.

While all available studies have focused and increased their efforts on the water-conservation efficiency, very few have talked about how they affect the surrounding conditions. Therefore, here, there’s a need for more improved research. This will help in approving their use, especially in large-scale holding tanks and ponds.

What Do Advanced Tests Say?

According to 2007 studies, an increase in surface area will makes it difficult to fix in these dam covers. Using the Wivenhoe Dam scholars also learned that:

With water surfaces above 67m, the dam recorded a 107.514km2 surface area and a water-holding level of 1,165,238ML

The same year, water surface level was between 50 and 53m above sea level

It also showed wind speeds of 10 m above sea level with vapor and air temperatures of 1.2m.

The Measuring Formula

People have used different calculations in measuring the loss of water into the atmosphere. In the above tests, the Penman-Monteith Equation proved to be quite effective. This formula puts into account changes in heat as well as other important things such as: Vapor pressure, Air temperature, and wind force or speed

How Do These Dam Covers Affect The Surrounding Environment?

We need to mention that these covers can cause serious problems to the surroundings. A good example is the Wivenhoe dam which supports a lot of animals and plants. Here, by blocking entry of sun-rays, plants will lack enough sunlight needed in making food. This will also affect the animals which rely on these vegetation for sustenance.

In almost the same way, low oxygen supply lowers water quality and kills other living creatures like the fish living in the pond. Besides, while preventing entry of sunlight has greatly reduced the levels of seaweed, other dangerous effects have been almost impossible to ignore.

For example, contaminating the water in the dam, which is located upstream, can seriously affect the lives of those living downstream. So, there’s a need for more improved studies on the use of these dam covers to make sure that they don’t destroy both plant and animal life.

Are They Affordable?

Did you know that floating and suspended dam covers can last for ten years? They require lower costs of installation and maintenance. Also, since they float freely on large and small-scale water surfaces, you won’t need to pay for more supportive systems

However, for larger areas of water, remember to put in place one or two supportive systems. Fencing is another extremely important step you will need to do. Although it’s something many forget to do, we have found it to be a brilliant way of keeping out humans and wild animals. Besides, it also protects the overall structure of the dam covers which makes them last for a long time.

Installation Problems

It’s important to maintain high levels of safety as you install either floating or suspended sheets as dam covers. Although water bodies will not look the same once you are through, understanding the importance of using them will help you to establish strong safety measures.

Here are other problems that come with the installation of floating and suspended dam covers.

Fear that these covers might detach and damage dam gates

The dam covers might be ineffective when piled up together

Some blocks are hardly operational and only destroy the structure of the covers

Differences in how they respond to changes in weather

Due to few information on the importance water covers, their application on large water surfaces is low

Some are expensive and unavailable

Areas Which Call for More Research

There’s still a lot to do in the study of floating and suspended dam covers. For instance, the physical side of these covers requires a long testing process. Here, some of the areas to keep in mind are:

The ability of gases and liquids to flow through

How much do they damage the quality of water?

Which supportive methods will you need?

Calculating wind reduction and solar radiation levels.

Remember that the installation location of these structures should be carefully studied. This will make sure the water quality and ocean life is not greatly affected. “So, are they easy to install?” This is another issue that continues to trouble many people.

Well, many believe that floating structures are easier to fix unlike the suspended sheets. “Just push them from the shoreline or throw them over the boat,” they say. Unfortunately, we’ve found that this is not always true. Both of them require a well-developed installation process if they are to function properly.

Wrapping Up!

You can now see the importance of using floating and suspended dam covers in reducing the release of water vapor into the atmosphere. Although they are sometimes quite expensive and some have high installation costs, they still have an extremely important role to play in evaporation reduction.

So, maintaining safe operation and the use of these covers should be looked at carefully before anything else. This will secure aquatic life and prevent unexpected damages in the dams or ponds.

Lastly, you can see that these are reliable and effective ways of conserving water. Furthermore, their use and availability will help us to avoid misusing this precious commodity not only in the region but in larger Australia. Good luck!