What are the downsides of rainwater harvesting?. Rainwater harvesting (RWH) is the collection and storage of rain, rather than allowing it to run off. Rainwater is collected from a roof-like surface and redirected to a tank, cistern, deep pit (well, shaft, or borehole), aquifer, or a reservoir with percolation, so that it seeps down and restores the ground water. Dew and fog can also be collected with nets or other tools. Rainwater harvesting differs from stormwater harvesting as the runoff is typically collected from roofs and other surfaces for storage and subsequent reuse. Its uses include watering gardens, livestock, irrigation, domestic use with proper treatment, and domestic heating. The harvested water can also be committed to longer-term storage or groundwater recharge.
Rainwater harvesting is one of the simplest and oldest methods of self-supply of water for households, having been used in South Asia and other countries for many thousands of years. Installations can be designed for different scales including households, neighbourhoods and communities and can also be designed to serve institutions such as schools, hospitals and other public facilities
What are the downsides of rainwater harvesting?
While rainwater harvesting has many advantages, there are a few disadvantages to consider.
- Not legal everywhere. Some states or municipalities may limit the amount of rainwater you can collect or outlaw it altogether. There are currently no federal restrictions placed on rainwater harvesting, so contacting your local authorities is the best way to determine the rainwater collection regulations in your area.
- Unpredictable rainfall. One of the biggest disadvantages of rainwater harvesting is the inconsistency of rainfall. If you rely on rainwater for gardening, washing your cars, or other applications, you may find yourself running out during times of drought.
- Limited by tank size. Rainwater harvesting becomes more expensive when you wish to store large amounts of water at a time. For example, if you use a 50-gallon rain barrel and it becomes full, you will not be able to take advantage of the next rainfall. If you wish to opt for a larger tank, you will need to spend substantially more money.
- Initial cost. Over time, rainwater harvesting can save you money on your water bill. However, the initial cost of a rain barrel and its components can turn people away from setting up a collection system at their homes.