Saving Tank Water From Evaporating

I visited a colleague's home for the easter weekend. He has a lovely house in the Manly suburbs. We had a very long break for work. He was very kind to invite me. Otherwise it would've been really hard for me to spend the 4th day without doing anything. I took a ferry from the circular quay to Manly. Its a great experience to travel in these ferries.

My colleague's house (he is my CEO!) is well equipped with all the needs. While surveying the house I noticed their swimming pool was covered in a blue rubber sheet. When I asked him why they covered it, he mentioned they had limited supply of water. If they fill the pool and leave it for a couple of weeks, all the water would evaporate and they had to fill the water again. Then they found out this solution of covering the whole pool with a rubber sheet. The local water bodies gave them this solution. This rubber sheet would look like the waste left after making hawaii chappals. This solution solved their water evaporation problems completely apart from protecting the pool and water from dust and waste material. Whenever they need to use the pool they just remove the cover, use the pool and cover it back again.

• Minimise the cooling of the pool by stopping evaporation and convection heat loss. This occures mainly during the night when the ambient air temperature drops below the temperature of the water in the pool. By creating a barrier between the water surface and the outside air, these losses are virtually eliminated.

• By keeping evaporation to a minimum, you not only save water, (approx 1.5 metres per year in the Sydney Metropolitan Area), but you also save on the cost of chemicals as you dont have to re balance you pool after topping up. It also reduces the amount of chlorine lost to the Suns’ UV Rays.
  
  
• Blankets keep the pool cleaner - about 80% to 90% of debris is kept out of the pool. This reduces the work load of your pool cleaner. Most types of pool cleaners will work quite happily under the blanket.

• Reduces pool heating costs by up to 50%. Even the cost of running solar system pumps is saved by reducing the amount of heat loss from the pool. Effectively 90% of heat loss is from the surface of the pool. By using a blanket in conjuction with Gas, Electric or Solar heating systems, significant energy cost savings can be made.
  
  
• Extend the swimming season. Even without other forms of heating on the pool, the addition of a pool blanket can result in a temperature increase of from 6 to 8 degrees in a pool that has a sunny aspect.

All these benefits are pretty good to the swimming pool owner.

But covering a pool with these sheet is an expensive affair. It costs considerable maintenance costs as well along with the high initial setup costs.

At my village we have a borewell and my father pumps it into a storage tank so that he need not depend on electricity to water his crops. But what he hasn't realised is, he is loosing huge amounts of water to evaporation and ground percolation. There are other problems as well. Most of these problems are same as the swimming pool owners. However, they have a solution now.

How about making this an expensive solution, alter it suitably to suit Indian conditions and apply it to my father's farming storage tank? Well I am working on that will post as soon as I have a workable solution.