What is Rainwater Harvesting. Advantages of Harvested Rainwater.

Simply speaking Rainwater Harvesting (RH) is collecting water from rain, storing it, and using it as a free resource. Rainwater harvesting promotes sustainable water management practices. Traditionally, rainwater harvesting has been practiced in arid or semi-arid areas of the world. However, today, with massive urban development, Rainwater Harvesting is proposed as a good sustainable environmental practice. It is a simple concept that can save much water from our planet and some money for you.

Reasons to Practice Rainwater Harvesting

a) RH is great for areas where there is inadequate groundwater supply or surface water resources are either insufficient or non existent. Rainwater harvesting is a good solution in these cases

b) Harvesting rainwater may help with preventing the rein runoff from going into sewer or storm drains and reduce reducing the water load on treatment plants on heavy rainy periods.

c) Urban flooding may be reduced by rainwater harvesting. Some cities face a two sided issue. They have little water but when it rains the city or town floods. RH can help reduce both issues.

Rainwater Harvesting Systems

Rainwater Harvesting Systems can be very simple. A water tank located under a down pipe from your roof gutter can be considered the simplest system. After all, you are collecting rain water from your roof and storing it for further use. On the other hand, there are huge industrial systems with large above or underground tanks, filters and pumps that do the same: collect water for

further use.

What are the uses for Harvested Rainwater?

Rainwater is untreated and as such it may be polluted. Rainwater harvested from roofs may contain animal and bird feces, dust, sand, pollutant particulates, pesticides (especially in rural areas), and many inorganic minerals (Ca, Na, K, SO4). All these make this water not drinkable if untreated. However, with proper treatment rainwater can be used for all purposes, including drinking. There are even low cost solar water disinfection systems available to treat water from rain.

Rainwater Harvesting is an interesting proposition for helping the environment and solves the problem of water scarcity in urban and rural areas. Many parts of the world have used since ancient times (India) and many urban new area are starting to implement systems to collect water form rain.


Frasier, G, and Lloyd, M. 1983. Handbook of Water Harvesting. U.S. Dept. of Agriculture, Washington DC US.