The Product Range of Our Company Previous Model

Rain water harvesting system for all of us.

The rain water that falls in your premises is wasted as it flows into the storm water drains. With the growing demand of water for various competing purposes it is the time for us to look at this natural resource that can be tapped with little effort.

Going back to our Traditions.

Rain water harvesting is an ancient technique that has been practiced in our country since ages. In a country where the annual rainfall is concentrated for just about 100 hours for an year, the only option in the absence of any "advanced technological" means, was to conserve and store the maximum possible portion of that rainfall. Our ancestors realized that if they do not make every raindrop count, then they would have to spend most of the year without water for their daily usage. Unfortunately under the British governance system the wisdom of the raindrop was neglected. The technological interventions which got water into our taps relied on large scale water impoundments in the upper reaches of rivers and pushed the wisdom of the raindrop into the background, today what we need is the wisdom of our ancestors, rediscover their concepts and adopt them to our place.

Potential of the Rain Water.

Whether it is a small house you are constructing or a country mansion or a multi-storied building, a simple system can help you harness the potential of the rain drops. The rain water harvesting system can be incorporated in layout plan at the initial building stage itself without much cost. With the rain water harvesting system, you can lower your water bills, prevent local flooding and also help recharge the declining water table. And contrary to local belief, it is simple and cheap. With growing urbanization, the percentage of hard areas in the city is increasing. Large tracks of open land are being brought into the urban areas for meeting the ever increasing demand for developed lands. In our own premises itself, most of the land is covered with hard surfaces like, the roof, the verandah, the driveway and the portico. Consequently, most of the rain that falls runs off the premises into the municipal storm water drainage system. The amount of water that can be harvested in our premises depends in the intensity of development and the annual rainfall pattern in the region. On an average, through a simple rain water harvesting system, about 40,000 liters of rain water can be harvested from a plot of 100 sq. meters in the area in a region receiving 60cm of rainfall annually.

Benefits of rain water harvesting.

Harvesting of the few centimeters of rain drops that fall within our premises not only reduces the chances of local water logging but also decreases our dependence on the ground water resource. This rain water that is harvested is pure with virtually no impurities and is suitable for all purposes. Use of rain water for seweage purposes, washing of vehicles, premises and other domestic purposes, landscaping and gardening which are the major component of water consumption reduces water bills considerably. Washing and swabbing of the floor with harvested rain water does not even leave any salt deposits in the floor that needs to be scrubbed away now and then. After filtration the harvested rain water can be put to many uses including drinking and cooking purposes.

Five components of rain water harvesting system:

  • Catchment area
  • Collection system
  • Filtration system
  • Storage/recharge system
  • Reuse system

How do you harvest the rain drop?

Rain water harvesting system can be as simple as an inverted umbrella that collects the rain water and directs it into a container. Alternatively, it can be a complex system that harvests every drop of rain that falls in your premises and then puts it back into your water supply system. The choice of the system depends on the size of the catchment area, the amount of rainfall received, the end use of the harvested water, and of course, your budget. The rain water harvesting system can not only be incorporated in a new construction but can also be added to any existing structure.

Catchment Area:

The area of your premises in which the rain water fall is known as the catchment area. The nature of the catchment area determines the amount and quality of the rain water that can be harvested. The various common surfaces have been assigned certain values of "runoff coefficients" depending on the amount of rainfall that runs off their surface. The rainwater runs off the hard and smooth surfaces faster than off the soft surfaces. Hence the run-off coefficient for harder surfaces is more than that of the soft surfaces. The annual rain water harvesting potential of your premises can be calculated by multiplying the respective area to the runoff factor and the amount of rainfall that is received annually. The ideal rain water harvesting system aims to harvest the maximum portion of this potential and achieve "zero-run-off" in your premises.

Collection System:

The collection system directs the rainwater falling in your premises into the filtration system through a system of drainage pipes and channels. The collecting pipes collect the rain water falling onto the roof, running off the driveway and flowing off the other open areas and deposit it into the filtration chamber. The design of the collection system is done in such a way as to collect the maximin of amount of run-off that is generated in the premises.

Pre-storage/Recharge Filtration:

The rain water dissolves the impurities that are present on the surface as it flows through the premises into the collection system. Therefore it is advisable to keep the catchment area free of any chemical or other harmful impurities. At times, it is also advised that the run-off of the first few minutes of the rain be allowed to flow out of the premises. This washes away most of the impurities that may be possibly present on the surfaces. However this call for certain design modifications and vigilant users. Therefore, it is always safer to make the rain water run-off pass through a simple filtration pit before it flows into the storage or the recharge structure. This way, most of the impurities that get dissolved in the rain water run-off get removed before storage/recharge.

Storage/Recharge System:

Depending on the amount of rainwater that needs to be harvested and the purposed end use of the harvested rain water, an appropriate storage or recharge system is designed. In areas with rainfall evenly spread over the year, a simple storage cistem can be designed on the basis of the daily water requirements. However in areas where the rainfall id restricted to a few months of the year, recharge systems are more appropriate. The design and the location of these recharge systems is site specific and needs to be evolved as per the requirements.

Reuse System:

The reuse system depends on the need of the individual owner and the amount of harvested rainwater. The harvested rain water that has been passed through the simple pre-storage filtration system can be utilized for all uses except drinking and bathing. After adequate filtration the same water can also be made fit for human consumption. A harvested water distribution system can be used in the premises for gardening the green areas or for use in the toilets. Again the re-use distribution system shall be site specific and the design shall be dictated be the site specifications.


Rain water harvesting system requires occasional maintenance, but this can be easily accomplished. Debris and leaves should be filtered before storing the water by placing screens over gutters. Debris screens over gutters should be cleaned periodically and storage tanks should be drained and cleaned regularly. Water kept in tanks should be covered to minimize algae growth and eliminate the potential for any mosquito breeding.


The effectiveness of a rain water harvesting system lies in its ability to meet the site specific requirements and end use preferences. Though simple, these systems are site specific and need to be detailed out before implementation. With the decreasing availability of water, rain water harvesting presents the best option for time to come.