Turn the heavy rain into a valuable resource

You can use a gutter to harvest rainwater. Photo | File

What you need to know:

  • Rain is the main source of fresh water and we need it for crops and other plants including pasture to grow well. When there is no rain for long periods our crops die, and there is no pasture for our animals.

After a prolonged severe drought earlier in the year the country began receiving heavy rainfall resulting in big floods and the destruction of buildings and bridges in Kampala and other parts across the country.

Sometimes rain, which is so important for agriculture, turns into a curse when we see massive floods and entire crop gardens destroyed by rainwater runoff.

Source of life

However, rain is the main source of fresh water and we need it for crops and other plants including pasture to grow well. When there is no rain for long periods our crops die, and there is no pasture for our animals. Insufficient rainfall leads to rivers drying up and a reduction of water volumes in other water bodies.

As climate change continues to bite we are likely to experience more rain scarcity.

According to Africa.com, the Nile, which runs from Uganda to Egypt, is critical to the survival of millions of Africans. However, a combination of climate change and human overuse is drying up the river, worsening conditions for farmers who are concerned about low harvests and power outages. The Nile basin spans 11 countries, including Tanzania, Burundi, the Democratic Republic of the Congo, Rwanda, Uganda, South Sudan, Ethiopia, and Egypt, which hosted hundreds of heads of state gathered recently for the COP27 climate conference, in Sharm el-Sheikh.

The Africa.com report further states: “The flow of the world’s second-longest river has decreased from 3,000 cubic metres per second to 2,830 in the last 50 years. According to UN forecasts, a lack of rainfall and increased droughts in East Africa will cause river flow to drop by 70 per cent by 2100. The world body predicts a loss of 75 per cent of available water per local resident.”

Harvesting rainwater

The best approach to this sad situation is to invest more in rainwater harvesting which is the process of collecting rain and storing it for use in times of rain scarcity.

It can be collected from house roofs, and all well-paved areas such as concrete courtyards, or even rocks. Some people build water dams in the valleys and trap millions of litres of rainwater.

Many farmers harvest rainwater by digging holes in gardens and fitting them with plastic or polythene sheets and tarpaulins where ground runoff rainwater may be stored for several weeks. 

Rainwater harvesting should be the main focus of government spending since life is impossible without water and, as an agricultural country; our economy heavily depends on water.

Why harvest rainwater

The main purpose of rainwater harvesting is to save and conserve water for future use.

It is intended to meet the increasing demand for water as our population grows bigger. It is needed for such purposes as irrigation and watering livestock, especially during times of water scarcity. It reduces soil erosion and flooding of roads since some water is trapped and kept in tanks.

Eden Kamugisha who is both a crop and livestock farmer in Masaka City says, “Rainwater is a free gift from nature which all farmers must take advantage of. Of course, there is always some expense to undergo such as buying or constructing the water tank. But after the gadgets have been acquired the farmer keeps harvesting free water every rainy season.”

Irrigation purpose

Kamugisha believes that saved rainwater can be used to carry out irrigation for crops such as vegetables and to water some animals under zero-grazing.

“It is the best option for smallholder farmers,” he says.

We must, however, be mindful of the fact that it is often difficult to predict when the rains will start and whether they will be in sufficient amounts. Much as it is the best option for smallholder farmers working in rain-scarce conditions, rainwater harvesting is not always reliable and it is out of reach for many cash-trapped small-scale farmers. It requires some technical skills to install the gadgets including tanks which must be paid for.

Dangers of rainwater

Care must always be taken before using rainwater.

“It is not always clean or safe,” says Gertrude Namyalo, a prominent farmer vegetable farmer at Kyanukuzi Kisekka Sub-county Lwengo District.

“Some birds ease themselves on rooftops and some dead lizards and bats get caught up in the gutters and pipe systems where the water passes to get to the tank. The water could be a source of diseases for poultry and other livestock.” 

Her concerns are also reflected in the study report by David Baguma, Syed Alijunid, Jamal Hashim, Helmut Jung and Loiskandl Willibald titled: “Rainwater and Health in Developing Countries: A Case Study on Uganda.” (University of Natural Resources and Life Sciences, Vienna)

 It says: “In rainwater harvesting households, we found that usage instructions (including waterborne health risks) were not sufficiently supplied to rural households. Principally, water pathogens continue to cause household challenges such that water-related diseases are contributing to morbidity rates and economic burdens in Uganda and other similar countries in the developing world.

These problems are compounded by various mechanisms: the way water is distributed, via the droppings of rodents or birds that contaminate the catchment of rainwater harvesting systems, through pollution of the water during the collection process, as well as by weaknesses in the pipe systems where sewage leakages or environmental pollutants infiltrate the pipes, and lack of replacement of old water distribution systems affected by climate change over decades, coupled with poor drainage systems in cities, suburbs and slum areas.”


In their groups, farmers practising rainwater harvesting should seek guidance from the Ministry of Water and Sewerage or other experts to ensure that their stored water is safe for both human and livestock consumption. All water for drinking including rainwater should be boiled and kept in clean containers.