Tuesday, April 8, 2014

Rain Water Harvesting

Rainwater harvesting is the accumulating and storing, of rainwater. It has been used to provide drinking water, water for livestock, water for irrigation or to refill aquifers in a process called groundwater recharge. Rainwater collected from the roofs of houses, tents and local institutions, can make an important contribution to the availability of drinking water. Water
collected from the ground, sometimes from areas which are especially prepared for this purpose, is called Stormwater harvesting. In some cases, rainwater may be the only available, or economical, water source. Rainwater harvesting systems can be simple to construct from inexpensive local materials, and are potentially successful in most habitable locations. Roof rainwater can be of good quality and may not require treatment before consumption. Although some rooftop materials may produce rainwater that is harmful to human health, it can be useful in flushing toilets, washing clothes, watering the garden and washing cars; these uses alone halve the amount of water used by a typical home. Household rainfall catchment systems are appropriate in areas with an average rainfall greater than 200 mm (7.9 in) per year, and no other accessible water sources.

There are a number of types of systems to harvest rainwater ranging from very simple to the complex industrial systems. The rate at which water can be collected from either system is dependent on the plan area of the system, its efficiency, and the intensity of rainfall (i.e annual precipitation (mm per annum) x square meter of catchment area = litres per annum yield) ... a 200 square meter roof catchment catching 1,000mm PA yields 200 kLPA.

Rainwater harvesting systems channel rainwater that falls on to a roof into storage via a system of gutters and pipes. The first flush of rainwater after a dry season should be allowed to run to waste as it will be contaminated with dust, bird droppings etc. Roof gutters should have sufficient incline to avoid standing water. They must be strong enough, and large enough to carry peak flows. Storage tanks should be covered to prevent mosquito breeding and to reduce evaporation losses, contamination and algal growth. Rainwater harvesting systems require regular maintenance and cleaning to keep the system hygienic.

A subsurface dyke is built in an aquifer to obstruct the natural flow of groundwater, thereby raising the groundwater level and increasing the amount of water stored in the aquifer.

The subsurface dyke at Krishi Vigyan Kendra, Kannur under Kerala Agricultural University with the support of ICAR, has become an effective method for ground water conservation by means of rain water harvesting technologies. The sub-surface dyke has demonstrated that it is a feasible method for conserving and exploiting the groundwater resources of the Kerala state of India. The dyke is now the largest rainwater harvesting system in that region.

Kerala leads the way!
There are good opportunities for Rainwater harvesting in Kerala because Kerala is blessed with two rainy seasons. Kerala faces severe water scarcity between February and mid May every year. During summer, there are drinking water shortages. During this period drinking water and other water purposes become unavailable. This is expected in the coming years. In spite of 44 rivers and world's largest water well density, per capita surface water and groundwater availability of the State is lower than that of arid States of India. Moreover, Kerala has one of the lowest per capita rainwater availability in the Indian sub-continent and it is still decreasing over the time, even though it receives 3000 mm of rainfall, which is around 3 times the Indian national average. The high variations in spatial and temporal rainfall add to the complexity of problems associated with water management faced by the State.



:-from www.envirospectra.org

16 comments:

  1. This blog website is actually valuable. we provide post harvest handling technology online at affordable prices. for more info visit our website.

    ReplyDelete
  2. I agree with your point of view of this article. we provide Post Harvest Solutions Australia at affordable prices. to know more visit our website.

    ReplyDelete
  3. Hefty strong squanders materials will settle down the compartment shaping a layer know as slime. https://congtyhutbephot.com/thach-that-ha-noi/

    ReplyDelete
  4. Thusly, consistently sow what you want to harvest. You may disclose to me that you planted great seeds yet you are yet to get your harvest. Be totally guaranteed that it is as yet coming. undefined

    ReplyDelete
  5. I can recommend primarily decent and even responsible tips, as a result view it: Bubblers

    ReplyDelete
  6. Father quit cultivating twenty years prior and says he ought to have halted ten years before that. He was an honor winning farmer and a heavenly finance manager. He generally created as much on every section of land as normal farmers did on handfuls or even 100 sections of land. Europa-Road kombájn szállítás

    ReplyDelete
  7. Thanks for including me here amongst so many great content creators. So much inspiration, motivation, and gold nuggets to be found on this page – Love it! Share some for paramount wastewater solutions.

    ReplyDelete
  8. Proficient business and private window cleaners put resources into quality upkeep techniques.
    https://www.westseattlewindowcleaner.com/window-cleaning-seattle-low-cost-and-high-quality

    ReplyDelete
  9. Pretty good post. I just stumbled upon your blog and wanted to say that I have really enjoyed reading your blog posts. Any way I'll be subscribing to your feed and I hope you post again soon. Big thanks for the useful info. BioHazard Cleanup

    ReplyDelete
  10. This article gives the light in which we can observe the reality. This is very nice one and gives indepth information. Thanks for this nice article. Water Damage

    ReplyDelete
  11. This is very informative and interesting for me. Thank you for such a wonderful post about Flood damage restoration okc and for sharing. God bless you.

    ReplyDelete
  12. Mortgage holders avoid recruiting a waterproofing worker for hire since they are worried about the tremendous expense of the waterproofing project. https://ecfoundations.com/

    ReplyDelete
  13. Water restoration experts understand the complexities of water damage and implement appropriate restoration strategies. water damage restoration

    ReplyDelete
  14. Baseboard heaters are a great way to warm up drafty areas. replacing water heater raleigh

    ReplyDelete