Abstract

Rain water harvesting system, in its broadest sense, is a technology used for collecting and storing rain water for human use from roof tops, land surfaces or rock catchments using simple techniques such as pots and barrels. Though building permitting agencies require this system in place, it is still not effectively implemented. Rainwater harvesting has been practiced for thousands of years. It is an important water source.

Introduction

I had supervised a small township of 256 dwelling units there green technology is used, the centralized rwhs to collect water through storm water drainage system , the surface water and water from roof top can be collecting to a large reservoir, after treatment this is used for house hold requirement. This shall be adopted for big townships.

Body

Rain water is relatively clean and the quality is usually acceptable for many purposes with little or no treatment. The properties of rain water are usually better than ground water (which may be contaminated).

Rain water collecting system consists of different phases, the collecting phase, conveying phase, storage phases and Distributing phase.

Water safety, like food safety is a major

priority in today world. Rain water collecting from roof tops, parking lots, play ground etc. has very few negative impacts compared to other technologies for water resource development.

Advantages of rain water harvesting include but not limited to supplement to other water resources used as a buffer during emergency or breakdown of other sources, reduces storm drainage load and flood in cities, reduces water bill, reduces soil erosion, reduces demand/consumption of ground water.

Disadvantages include but not limited to unpredictability of rain, initial cost, regular maintenance, storage limits

RwHS is a system fast developing and is most beneficial to areas that receives very high rainfall.

Concrete and asphalt are covering our cities and this causes large reduction in rainwater permeating which in turn increase and speeds up the surface flow causing drains and sewage blocks, overflowing of rivers and streams that repeatedly causes flood.

Towns and cities instead of continually discussing this, should try to educate the public about the need and urgency to use these technique process, which is in short collect rain water when it rains stored and utilized later.

Rain water utilization, water conservation and waste water reclamation should be done in the government level by municipal ordinances and regulations. Standardization of materials, design of rainwater utilization system etc will ease the implementation process.

Various implementation policies should be established. Leadership is very important and local self governments must take the initiative to promote the concept of water resources independence and restoration of the natural hydrological cycle. Consideration should be given to subsidizing facilities for  rainwater utilization.

Training to support rainwater utilization is very important. It is also important to promote the development of efficient and affordable devices to conserve water. Some of which can be given free.

Conclusion

Through existing network of covered storm water damage, rainwater can be collecting to a large reservoir about 5 hectare and 10 m depth below ground level suitable for a township of medium population.