Water Harvesting & It’s Importance
Using harvested rainwater has become a viable option for supplying water for farms and even household use. Harvested water has many uses e.g to water plants, for livestock, fish farming (to fill ponds) etc. Besides this, you can use it in households for toilet flushing, laundry, bathing and many more.
A good time for farmers to harvest water is during the rainy seasons. This water will cater to the shortage or low rainfall that they may experience later.
Water harvesting is the collection and storage of rainwater for later use. The collection system mostly used in Kenya and other parts of Africa is the roof. The water flows from the roof to the gutter and eventually into storage tanks for onward use.
Advantages/ Benefits of Rainwater
- It is a relatively clean and free source of water. You save money when you use it.
- Water harvesting promotes self-sufficiency and helps conserve water.
- The water is better for farming and gardens because it is not chlorinated.
- It uses simple technologies that are inexpensive and easy to maintain.
- It can be used as a main source of water or as a backup source to municipal water and boreholes.
How to Harvest Rainwater (Methods)
- Rain Barrels
This method is the most common and one that many people are familiar with. The gutters and downspouts along the edges of your roof are the water transportation system. You put the barrel under and collect the water flowing from the roof. These barrels usually don’t take up much space so are convenient. Raise your barrel off the ground to get good water pressure especially when using a pipe/ hose.
- Water Pan
A water pan resembles a dug out pond lined with dam liners. It collects and stores runoff rainwater. During the rainy season, the pan fills up and water is used when the rains stop. You can pump the water from the water pan into a tank then to drip lines in your farm or greenhouse.
To prevent water loss in the pans through evaporation, sprinkle water-holding micro-fiber polymers. They are available in agrovet stores.
To read more on water pans and ponds, please see these Training Notes by Prof. Bancy Mati.
- Water Cisterns
The cistern is the single largest investment for most rainwater harvesting systems. Most cisterns are cylindrical. Cisterns use gutters and downspouts to collect the rainwater. Most experts recommend keeping the tank tightly closed. This will prevent evaporation and keep out sunlight, (which will support algae growth) and animals (insects, rodents, and amphibians).
Finally, as you can see, as a farmer, you can reduce your water scarcity challenges by investing and engaging in water harvesting practices.