Rainwater harvesting is not a new idea. People have been harvesting rainwater for thousands of years. Freshwater is a finite resource. Only 2.5% of the world’s total water supply is freshwater. Since freshwater only makes up such a small percentage means that we could run out one day, there is a limited amount. As the population increase and cities, we as gardeners and humans, in general, should do a better job with preservation. Rainwater harvesting is an easy way to get started.
By 2030, more than 60% of the world’s population will live in urban areas. One out of every three people will live in a metropolitan city. Imagine the stress that will be put on our water system. Now, imagine the impact we could have on the environment if we changed our urban hydrology and began to harvest rainwater.
The Benefits of Rainwater Harvesting
Did you know that 1″ of rain across a 1000sqft roof can produce over 6oo gallons of captured rainwater? Now ask yourself, how often does it rain where I live? How many gallons of water do you use in your garden daily, weekly, or yearly? What if you could save money and get a better product. Would you? I know I would, and that is what rainwater harvesting does. It can save you money, protect the environment, and is better for your plants than tap water.
A water cycle shows the continuous cycle of water from the atmosphere to the earth and back. Once we understand the water cycle, we will realize why capturing rainwater can positively affect our ecosystems.
- Evaporation. When exposed to heat, surface water turns into water vapors. The majority of evaporation comes from large bodies of water like oceans, seas, lakes, and rivers. So if we pollute these, then the entire water system is affected.
- Condensation. As the water vapors ascend in the atmosphere, they change into particles of ice/water.
- Precipitation. When the air cannot hold any more moisture, the moisture is precipitated and falls back to the earth. The condensed water vapors, and clouds, fall back to the ground in the form of precipitation. Precipitation can be snow, rain, hail, sleet, and drizzle.
- Runoff. As the precipitation falls, it causes runoff. Runoff occurs when the water runs over the surface of the earth. As water runs over the ground, it moves soil, minerals, and more into channels, rivers, bayous and eventually ends up in lakes, seas and oceans.
- Infiltration. The water that does not runoff is absorbed deep into the soil. This water works its way down through sand and rocks and refills the level of underground water tables.
More Benefits of Rainwater Harvesting
The benefits of rainwater are linked to the world’s water cycle in many ways.
- Avoiding runoff to reduce soil erosion and any pesticides, fertilizer, or pet waste entering the water stream. In urban areas, the largest source of pollution comes from landscapes. Collecting and utilizing rainwater to apply to the landscape is an efficient and environmentally friendly way to conserve water.
- Reduce our dependence on the limited freshwater supply.
- Save money
- Offset drought periods
How To Use Rainwater
- Irrigation. This is the most popular choice. If you install your rain barrel on stands higher than your garden, you can use science to do the work for you. This setup is known as gravity-fed irrigation. Every 2.5′ elevation above the water outlet creates one pound of pressure. If you cannot elevate your rain barrel, look into an external pump. This pump will help you move the water from the barrel to the garden.
- Uses the stored water to refill ponds, fountains, birdbaths, and even swimming pools.
- Use the stored water to wash vehicles.
Saving rainwater conserves water, decreases your water bill, helps clean up the water cycle by reducing the impact on groundwater, and minimizes susceptibility to drought.