How Karimenu II Dam, new partnerships are reshaping water security

Water connects us. In Gatundu North, Kiambu County, the Karimenu II Dam has become a lifeline for Nairobi and beyond, feeding taps, farms and even the national power grid

On September 11, 2025, it became the stage for a major environmental milestone with the launch of the Upper Tana and Mid-Galana Water Stewardship and Watershed Restoration Project, a multi-partner initiative to secure Kenya’s most critical water towers against mounting threats.

Commissioned in 2022, Karimenu II Dam supplies more than 70 million litres of water daily to Gatundu, Ruiru, Juja and parts of Nairobi.

It complements other reservoirs such as Ndakaini and Sasumua, but its role is outsized.

According to the Upper Tana Nairobi Water Fund, this watershed provides about 95 per cent of the capital’s water supply and over 80 per cent of the country’s hydropower capacity. Yet demand far outstrips supply.

Nairobi requires around 790,000 cubic metres of water daily against an available 525,000 cubic metres, leaving a shortfall of 265 million litres or a third of the city’s needs.

The new initiative launched at the dam’s banks seeks to close some of these gaps.

Backed by a 1.65 million US dollars investment from the Coca-Cola Company in Africa and Coca-Cola Beverages Africa, the project will replenish 562 million litres of water for drinking, sanitation and farming.

The project will also restore more than 10 kilometres of riparian zones with 20,000 indigenous trees and install 500 farm ponds to capture runoff for irrigation.

It will also plant 130,000 fruit trees expected to generate 600,000 US dollars annually by year four, directly linking conservation to livelihoods.

The restoration work will extend across six counties including Kiambu, Nairobi, Machakos, Kitui, Makueni, Kajiado and Taita Taveta.

For the government, the timing could not be more urgent. Representing the Water and Sanitation Principal Secretary Julius Korir, Athi Water Works Development Agency CEO Joseph Kamau said the initiative aligns with Kenya’s Vision 2030, the Bottom-Up Economic Transformation Agenda and the Sustainable Development Goals.

“This project is about more than just conservation, it is about securing our future,” Eng Kamau said.

“It is about nature-based solutions that empower communities and build resilience. It is about ensuring that water is life not just today, but for generations to come.”

Nature Conservancy Africa Regional Director, Ademola Ajagbe, echoed this call, saying that partnerships must be the backbone of Kenya’s water strategy.

“Nature based solutions are one of the keys to addressing the existential water crisis,” he said.

“We have seen how simple techniques like rainwater harvesting and inter cropping can transform a farmer’s income while improving water quality downstream. The question is how can we ensure many across Kenya can benefit from these interventions?”

Ajagbe referred to a farmer who, after joining the Upper Tana Water Fund, shifted from relying on rain fed cabbage harvests worth only five shillings each, to selling irrigated cabbages for seventy shillings in the dry season.

The higher earnings enabled her to educate her children and build a permanent home.

“This is not just about water,” he said. “It is about people, climate impact and meeting the needs of today.”

The importance of this watershed was underscored by Eddy Njoroge, President of the Upper Tana Nairobi Water Fund.

“The Upper Tana provides about 85 per cent of Nairobi’s water and over 80 per cent of Kenya’s hydro capacity,” he said. “It is not just important in terms of water supply, it is vital for power and for the country’s growth.”

Private sector partners are positioning themselves not as sponsors but as co-owners of the solution.

“Water is essential to life, to our beverages, as well as the communities that we serve,” said Floor Overbeeke, Coca-Cola’s Senior Director and Sustainability Lead for Africa.

“Together with partners, we invest in projects to improve watersheds that supply water for drinking, agriculture and manufacturing. Where possible, we use solutions within nature to help address local challenges.”

Coca-Cola Beverages Kenya Managing Director James Bowmaker emphasized that water stewardship is now central to the company’s operations.

“We have a responsibility to assist those who face water scarcity and to help protect local resources where we operate, especially in places with the biggest challenges,” he said.

Local voices are also shaping the conversation. Elizabeth Wathuti, founder of the Green Generation Initiative (GGI), highlighted the importance of community ownership, particularly by women and youth.

“Water does not come from taps, it comes from catchments,” she said.

“If we do not protect them, millions will go without. We are making sure communities are empowered to see value from conservation whether through fruit trees, clean cooking solutions or sustainable farming. Because if people’s basic needs are not met, conservation will not hold.”

The Ministry of Environment and Forestry placed the project within the broader climate policy framework.

Speaking on behalf of Principal Secretary Festus Ng’eno, Vicky Chepkorir said:

“Climate change has become a reality and a constant threat to our communities. Farmers bear the brunt through erratic weather that reduces yields, incomes and water access. Innovative partnerships like water funds are a much needed boost to support adaptation and conservation.”

The symbolism of the day was not lost on the community. Kikuyu elders planted a sacred Mugumo fig tree at the site, a ritual rarely performed and seen as a renewal of life.

“We are very happy today because we have planted a Mugumo tree,” said community leader Njoroge Mutugu.

“Normally, it is God who plants it. Planting one here is a sacred act. It means the community has been blessed to safeguard this land and its water.”

Beneath the celebration, challenges persist. Some residents remain dissatisfied with delays in compensation for land acquired during dam construction. Engineer Kamau acknowledged the concerns.

“The compensation process has been delayed, but evaluations are complete and reports have been submitted to the National Land Commission. We expect the process to move forward soon.”

What is clear is that the Upper Tana model has already proven replicable. From the Eldoret E10 Water Fund launched in 2022 to emerging initiatives in the Yala Nyando basin, Kenya is exporting lessons in public-private partnerships to other counties. Internationally, the Coca-Cola system has pledged nearly 25 million US dollars by 2030 to support similar efforts across 20 African countries.