Listen to This Article Enhance your reading experience by listening to this article.

A recent media workshop on integrated water resource management revealed alarming trends threatening Nairobi’s underground water sources. As a vital resource supporting agriculture, industry and daily life, these water sources – known as aquifers – are bodies of rock and sediment holding groundwater from infiltrated precipitation.

Kenya’s highest-yielding aquifers are located in the Rift Valley, Athi, Tana, and Ewaso Ng’iro regions, though recharge rates remain low in arid and semi-arid zones. The situation in Nairobi has become particularly concerning, as I witnessed firsthand shortly after the workshop.

In an upmarket estate, I observed two boreholes being drilled merely two metres apart. Further investigation in Waithaka and Dagoretti Corner estates revealed similar scenarios, with one notable case where a deeper borehole had depleted the surrounding aquifer, forcing neighbours to collect water with jerricans for domestic use.

These observations raised crucial questions about permitting processes, impact assessments and water quality concerns. Experts’ warnings that “Nairobi is already in the red as far as groundwater is concerned” suddenly felt very real.

Research by Samson Oiro from the Water Resources Authority demonstrates the severity of the situation. Since the mid-1970s, Nairobi’s groundwater abstraction has increased tenfold, matching the city’s urban population growth. Groundwater levels have declined at a median rate of six metres per decade since 1950, with some areas experiencing drops of up to 46 metres. Meanwhile, built-up areas have expanded by 70 per cent since 2000. Current trends suggest these figures could increase sixfold by 2120.

The problem intensified during the Covid-19 pandemic, particularly in upmarket areas like Kilimani and Lavington, where highrise developments have increased water demand. The situation was further exacerbated by the now-defunct Nairobi Metropolitan Services’ initiative to supply informal settlements with water through numerous new boreholes.

While the outlook seems grim, there are potential solutions. Nakuru County offers a promising example through its efforts to protect the Kabatini aquifer using biodigester toilet innovation, providing a model Nairobi could follow.

As a water-scarce country, Kenya faces several critical challenges in water resource management. First, there’s an urgent need to strengthen water governance mechanisms to achieve UN Sustainable Development Goal 6, which encompasses not only drinking water, sanitation and hygiene but also water quality and sustainability.

Additionally, catchment management requires greater attention. Current priorities often focus on downstream investments like water abstraction for irrigation, but we must consider how to de-risk these investments and ensure a sustainable water supply. Public awareness is crucial – people need to understand that water originates from catchment areas, not simply from taps.

The decline in groundwater levels primarily occurs when extraction rates exceed natural replenishment. Multiple factors influence these levels, including geology, climate, and land use. The current situation in Nairobi demonstrates how rapid urbanisation and population growth can strain natural resources beyond their sustainable limits.

The case of the Ondiri wetlands in Kikuyu, Kiambu county, a renowned underground water source for Nairobi, serves as a stark reminder of the consequences of uncontrolled development and increased water demand. However, with proper management strategies, innovative solutions, and increased public awareness, there’s still hope for protecting and preserving these vital water resources for future generations.

— The writer is a Sub-Editor with People Daily-