It has finally started raining; please buy a water tank

Tuk-tuk ferrying water tank at Bokoli area along Sikata- Kimilili road. [Benjamin Sakwa, Standard]

It's now official-that the much awaited long rains season between March and May may not be enough to wet the patched farms across the country.

According to the Kenya Meteorological Service Kenyans should only expect normal to below-average rainfall, this, after five dry seasons that sent millions of Kenyans to hunger.

However, all is not lost, but only if Kenyans heed the weatherman's advice for optimal utilization of the rains-however little-including investing in water harvesting tanks.

Like Noah of the Bible, the weatherman is telling Kenyans that, whether in low amounts or at optimal levels, the rains are here- buy water tanks.

Already, some parts of the country have reported rains, with the weatherman predicting that more rains are expected in the Lake Victoria Basin, the Highlands East and West of the Rift Valley as well as the South and Central Rift Valley.

But the gospel of rainwater harvesting is yet to sink in. Yet it has been preached over and over again as one of the best ways to confront perennial dry spells across the country. Sadly, few of Kenya's estimated 12.2 million households pay attention to the weatherman sermons from the dry plains.

Granted, sinking more dams is the long-term solution and the country spends billions of shillings on this cause. But every household must make it its mission to harvest as much water as possible.

Big or small, water tanks may not cost billions of shillings as dams do, but collectively, they can hold more water than all of Kenya's dams combined.

It is simple math that if each of Kenya's 12.2 million-plus households had a 1,000-litre water tank, the country would harvest at least 12 billion litres of water from one downpour. This, is equivalent to 136 Nairobi Dams, or three Nairobi Dams in each county.

Going with the price of Sh8,000 for a 1000 litre tank, it would cost Sh98 billion to ensure that each homestead in Kenya has 1,000-litre tank. This cost is just slightly more than the Sh82 billion budgeted for Thakwe Dam on the border of Makueni and Kitui.

The 688 billion litre-dam, which is still under construction, has been on the pipeline since 1953. Unlike dams, which take time construct and to fill (if they ever get filled at all), it takes only 250 ml of rain falling on a five-mabati roof to fill up a 1,000 litre-water tank.

Australia's leading water tank manufacturer, National Poly Industries gives a simple formula for calculating how much water can be harvested from various roofs.

According to the water tankards multiplying the rainfall received in millimeters by the area of your roof gives you a rough estimate of the number of litres to expect your roof. This means that a four metres area mabati roof-about the size of five mabatis- can collect 1,000 litres of water in arid and semi-arid areas that on average receive 250 millimeters of rainfall yearly.

Simply put, there is no reason to let a single drop of rain go to waste-not after Kenyans have survived the worst drought in the last 40 years.

-Mr Muchiri is a journalist