As our freshwater sources are limited, dwindling, and inadequate for the ever-expanding population, rainwater can be used to bridge the gap between supply and demand.
Theoretically, rainwater is the purest form of water. When water evaporates by the heat of the sun from the earth’s surface, it leaves behind undissolved and dissolved impurities. When the clouds pour down as rain due to condensation, the rainwater droplets would be as pure as distilled water.
However, as the raindrops fall, it collects the impurities present in the atmosphere and gets contaminated. This means rainwater is not potable as such.
Read on to know how to make the best of the rainwater collected and the benefits and uses of rainwater harvesting. You will find here the benefits of drinking rainwater and some interesting rainwater harvesting ideas.
What is rainwater?
When the sun shines, it heats everything on the earth’s surface including the water in all its forms. Water in the water bodies like oceans, rivers, and lakes evaporates and turns into water vapor. Even the water stored in the leaves of the plants is not spared in this process.
As moisture present on the earth’s surface turns into the gaseous form, it rises in the atmosphere due to air currents as it is less dense than the other constituents of the air. As air is cooler in the higher altitudes of the atmosphere, the water vapor turns back into tiny water droplets, forming clouds.
When the cloud becomes heavier with the addition of more and more water droplets, precipitation happens and it falls as rain or snow. Then the process starts all over again. This is called the water cycle. The water drops coming down as rain forms rainwater.
What does rainwater contain?
When the water in oceans and rivers evaporates to form clouds, it leaves behind soluble and insoluble impurities present in it. However, when it precipitates and comes down as rain, it absorbs gasses present in the atmosphere like oxides of nitrogen, sulfur, and carbon. However, it will be devoid of dissolved solids.
As rainwater is formed as a result of natural distillation, there will be no minerals or ions present in it. In coastal areas, the rainwater may contain traces of sodium chloride from seaspray. Unpolluted rainwater has a ph value of 5.6, which is slightly acidic.
The first rain after a long dry spell will contain dust and dirt as the water droplets gather them from the atmosphere on the way down. Moreover, the condensation process that converts water vapor to rain droplets is centered around a nucleus, which is a speck of soot, dust, or flake of salt.
It is a myth that rainwater is the purest form of water and is equivalent to distilled water. Though the process is the same, rainwater gets contaminated at various stages from its formation to it reaching the earth’s surface.
This doesn’t mean it is not usable. On the contrary, it is cleaner than the freshwater available on the earth.
Why is rain beneficial to humans?
Water is one of the essential elements for our survival. Rain is part of the water cycle that brings back the precious resource to everyone on the planet, even to those who have no easy access to other water sources like rivers and lakes.
Rain provides the vital freshwater needed for plants to grow and for humans and animals for drinking and cooking food. The human body is made up of 60% water and without it, humans cannot survive.
Besides providing freshwater directly to us, rain also replenishes the water used up from rivers, lakes, and other aquifers. The excess rainwater that falls on the ground seeps in and raises the groundwater level. The groundwater is another source of freshwater for us both directly and indirectly.
Why collect rainwater?
Collecting rainwater offers multiple benefits for us. It can be used directly for non-potable needs like gardening, washing, and toilet flushing. It can be used for potable needs like drinking, cooking, and showering after filtering and purification.
Here are some ways collecting rainwater can help us.
- Rainwater can supplement the public water supply.
- It can meet our non-potable demand without much effort.
- It reduces the wastage of energy for treating and pumping water at the public water supply.
- It can prevent flooding and soil erosion.
- It can reduce water contamination from the contaminants present in the ground.
- It can bring down our reliance on public water supply and reduce water bills.
- Rainwater has more oxygen content, which is good for plants.
- It is a good source of soft water.
- In areas with no public water supply, it offers sufficient water during dry months.
- Collecting rainwater by individuals can reduce the strain on the public water supply, thereby bringing down the cost of constructing and maintaining the infrastructure.
What are the benefits of drinking rainwater?
Rainwater is safe to drink as long as it is clean. People in many places across the world depend on rainwater for their freshwater needs. In fact, rainwater is the only source of water for many.
However, in most places, rainwater is not safe to drink as such. Rainwater on the way down may collect many pollutants. Once it reaches the ground, again, it can get contaminated. As long as the rainwater is collected hygienically, filtered, and purified, it is safe for drinking and cooking.
Rainwater has no added chemicals or toxins like chloride and fluoride. These are usually added to the public water supply to kill germs and make the water safe for drinking. However, too many of these chemical additives can cause health problems. As rainwater is free from these chemicals, it is safer.
Rainwater is known to promote healthy digestion. It is believed to help improve the health of skin and hair.
Drinking clean rainwater is a good way to keep yourself hydrated.
Some ways to collect rainwater
Collecting rainwater can be done in simple ways as well as using more complicated techniques of rainwater harvesting.
Using pails and barrels. Just leave them out in the open when it rains. Rainwater will fill them up in time.
In balconies and window sills. You can use smaller jugs and bowls to collect the rainwater falling on your balcony and at your window.
Using the gutters. Keeping a barrel at the base of the downspout of the gutter system is a simple method to collect rainwater.
Using a rainwater harvesting system. This is an elaborate arrangement to collect the rainwater falling on your property using an elaborate gutter system, collection tanks, and arrangement for filtration and purification. You just need to make sure that the gutters that carry rainwater for harvesting are clean and devoid of debris to avoid bacteria build-up.
How to use rainwater?
Rainwater can be used after basic filtration for:
- Watering houseplants, garden, and lawn
- For water features in the garden and outdoor ponds
- Flushing toilets
- Washing vehicles and similar needs
- For pets and livestock
- For protection from fires
- To add to the compost
Rainwater can be used for potable needs after proper treatment. Treating rainwater includes filtration, chlorination, and purification using UV light. The uses are:
- Drinking and cooking
- Washing vegetables
- Bathing and laundry
- Cleaning the premises
Rainwater harvesting can help you collect the rainwater your property receives without wasting a drop of it. It can help you collect the run-off systematically and hygienically for later use. The benefits of rainwater harvesting are numerous – from offering you freedom from public water supply to reducing your water bills.
As mentioned above, rainwater harvesting ideas are vast and varied. By using pails to modern rainwater harvesting systems. Irrespective of the method chosen, care must be taken to keep rainwater clean.
Freshwater is a critical resource and we need to do everything to preserve every last drop of it.