Rainwater Harvesting
“Harvest the rain and reaps the gain” s
Rainwater Harvesting
Exiguity of water is an austere issue in many densely populated regions. Elaborate structures with purification tanks, and systems, ranging simply from rain barrels, is a technology called Rainwater Harvesting that amasses and stores water for further human use. Rainfall is the sporadic and very minimal proportion of global precipitation available for human use. In cities, the rain falling on buildings, roofs, roads, and any other hard landscaping does not percolate into the soil and contrary directed into storm sewers for disposal.
Urban flooding in many areas is caused by impermeable surfaces and generating contaminated unusable water that is directed away from the resources of potable water. Rainwater Harvesting thus aids in salvaging the demand and supply of potable freshwater in significantly larger cities.
Types of Rainwater Harvesting
- Surface Runoff Harvesting
Areas dwelling in urban cities, have rainwater flows away as surface runoff. This runoff can be caught and utilize for recharging the aquifers by adopting appropriate methods.
- Rooftop Rainwater Harvesting
It refers to the system of catching rainwater where ever it falls. In rooftop harvesting, the roof turns into a catchment, and the collection of rainwater from the roof is done via a house or a building.
Influencing factors for Rainwater Harvesting
- Quantity of Rainfall
Precipitation is the foremost unusual and unpredictable variable and thus, to decide the potential water supply for a given catchment, solid precipitation information is required, ideally for a period of at least 10 years. Moreover, it would be a distant way better to utilize rainfall data from the closest station with comparable conditions.
- Pattern of Rainfall
The number of yearly rainy days impacts the requirements and plan for water gathering. The less the annual rainy days or longer the dry period, the more is the requirement for water collection in a region. In any case, on the off chance that the dry period is as well long, huge storage tanks would be required to store water. Consequently, in such regions, it is more attainable to utilize water to recharge groundwater aquifers instead of for storage.
From where to harvest rain
- Housetops
In case buildings with impenetrable rooftops are already in the place, the catchment range is successfully accessible free of charge and they give a supply at the point of consumption.
- Paved and unpaved zones
These include scenes, open areas, parks, stormwater channels, streets and pavements, and other open regions that can be successfully utilized to harvest the runoff. The most advantage of utilizing ground as a collecting surface is that water can be collected from a bigger range. Usually especially invaluable in regions of low rainfall.
- Waterbodies
The potential of lakes, tanks, and lakes to store water is gigantic. The harvested water cannot only be utilized to meet water prerequisites of the city, it moreover revives groundwater aquifers.
- Stormwater channels
Most of the private colonies have an appropriate arrangement of stormwater channels. If maintained flawlessly, these offer a basic and fetched successful implies for collecting rainwater.
The need for Rainwater Harvesting
- To surmount the inadequacy of water to meet our stipulation.
- Utilizing rainwater for sustainable development and enhancing the availability of groundwater in a specific place and time.
- To escalate infiltration of rainwater in the subsoil which had abated drastically in urban areas because of the paving of open area.
- By dilution, improving the quality of groundwater.
- To apprehend a decline in groundwater levels.
Advantages of rainwater harvesting
- Curtail Soil Erosion
Amid the rainy season, water is collected in huge capacity tanks, which moreover makes a difference in diminishing floods in a few low-lying regions. Apart from this, it moreover makes a difference in decreasing soil disintegration and defilement of surface water with pesticides and fertilizers from rainwater run-off, which results in cleaner lakes and ponds.
- Supplemental in Drought
Numerous countries, particularly those with parched situations, utilize rainwater harvesting as a cheap and trusted source of clean water. When drought occurs, water gathered in past months can be used. In parched situations, ridges of soil are developed to trap and avoid water from running down slopes and slants and improve the water system. Indeed, in periods of low precipitation, sufficient water is collected for crops to irrigate.
- Reduces demand for Ground Water
With an increase in the populace, the water demand is additionally ceaselessly expanding. The result is that numerous private colonies and businesses are extricating groundwater to fulfill their everyday needs. This has driven to the consumption of groundwater which has gone to an altogether low level in some areas where there’s huge water scarcity. Rainwater harvesting enables groundwater levels to be encouraged and maintained instead of exhausted.
- Easy to Maintain
Utilizing the water harvesting system gives certain advantages to the community. To begin with, harvesting rainwater permits us to utilize a vitality asset and energy way better. It is essential to do so since drinking water isn’t effectively renewable, and it makes a difference in decreasing wastage. Systems for the collection of rainwater are based on basic technology. The overall toll of their establishment and operation is much lesser than that of water filtering or pumping systems.
Disadvantages of rainwater harvesting
- Unpredictable Rainfall
Precipitation is difficult to foresee, and in some cases, small, or no precipitation can restrain the supply of water. If rain is unpredictable, the usage of a rainwater harvesting system can be critical to capture the rain where it does not fall.
- Initial High Cost
Depending on the system’s estimate and innovation level, a rainwater harvesting system may be fetched anyplace between $200 to $2000 and an advantage from it cannot be inferred until it is prepared for utilization. Like solar panels, the cost can be recuperated in 10-15 years, which depends on the amount of precipitation and advancement of the system.
- Maintenance Cost
Rainwater harvesting system requires standard support as they may get inclined to rodents, mosquitoes, algae growth, creepy crawlies, and reptiles. They can become breeding grounds for numerous creatures if they are not maintained properly.
- Storage is Limited
The collection and capacity facilities may moreover force a few kinds of confinements as to how much water you’ll utilize. Amid the heavy downpour, the collection systems may not be able to hold all water, which ends in progressing to channels and rivers. Rainwater collected amid the first blustery season is not required by plants until the dry season although it can be utilized for other family purposes. In any case, once the catchment is full, it cannot take advantage of future downpours.
Conclusion
The top notch of rainwater harvesting is “save the water of rain and do not let it to drain”. Hence, to curb the water scarcity, rainwater harvesting is one of the most effective tools in curbing it.