Projects

Thwake Dam Project Delayed Again Amid Setbacks

The government has so far spent over Sh36 billion on the project.

Updated on

August 29, 2026

AfDB officials visit the Thwake dam site on March 4, 2025. (Photo: Courtesy)

Completion of phase one of Thwake Dam in Ukambani, originally set for February 2024, has been pushed to April 2027, extending years of delay on the multi-billion-shilling project.

According to President William Ruto, the project encountered delays after funding ran out, but the government has now secured the funds needed to finish it.

“We had planned to complete it by December. However, it encountered problems after we ran out of money. We have now secured Sh10.6 billion for completing the dam. The money was approved last month,” Ruto said during a recent tour of Kitui County.

He directed the Ministry of Water, Sanitation and Irrigation and the contractor to fast-track the remaining works to allow communities to start benefiting from the project.

“I have directed the Ministry of Water and the contractor that we need to commission Thwake Dam by April so that communities can start accessing water for domestic use, for watering their livestock and for growing crops through irrigation,” Ruto said.

The latest delay adds to setbacks facing one of the country’s largest dam projects, which began nearly a decade ago and was expected to boost Ukambani’s economy and support Konza Technopolis.

In May 2025, Water and Irrigation Cabinet Secretary Eric Muuga attributed the delay to several factors, including the Russia-Ukraine war and the Covid-19 pandemic.

Appearing before the Senate plenary, Muuga explained that the global crisis had led to a shortage of explosives in the country and a reduced labour force.

“I would like to inform the Senate that due to the war in Ukraine, access to explosives needed for blasting the rock bed foundation is limited, slowing construction,” he stated.

Muuga also added that the weak foundation of the riverbed required excessive excavation, with embankment settlement taking six to nine months.

“Without proper settlement, the concrete cracks, which results in a weak dam,” Muuga said.

In June 2024, then Water Cabinet Secretary Zachariah Njeru reported that civil works and related activities were 93.6% complete, slightly ahead of the 92.8% target.

“The dam is expected to be completed by early December [2024], after construction commenced on March 27, 2018. The Ministry expects the dam to be filled with water over approximately two normal rainy seasons,” Njeru said during a tour of the project.

The Cabinet Secretary oversaw the completion of the embankment fill at the meeting point of the Thwake and Athi Rivers, located at the border of Makueni and Kitui counties.

“The filling of the embankment will now pave the way for the settlement of the dam and implementation of the bridge over the embankment, concrete face, installation of the gates and other downstream activities,” he said.

The project was originally due for completion on February 6, 2024. The contractor, China Gezhouba Group Company (CGGC), later applied for an extension, citing technical challenges including the El Niño rains. This pushed the expected completion date to December 2024.

Over Sh36 billion has been spent on constructing the dam’s embankment.

On December 31, 2021, CGGC successfully diverted a section of the Athi River into two giant tunnels to facilitate on-site excavation.

The company said the tunnels, 700 metres long and 12 metres in diameter, would be used as substitute waterways where the Athi River would change course before later joining the original path to the Indian Ocean.

This would allow the construction of a rock-fill dam wall—87 metres high—and the installation of main and minor spillways for excess water flow.

“We have decided to alter the river course flow so that major excavation works can be allowed when the river base is dry,” CGGC general manager Frank Keeh said.

Thwake Dam, the second-largest in the country after the Masinga Dam, which sits on the border of Embu, Kitui and Machakos counties, is jointly funded by the African Development Bank (AfDB) and the Government of Kenya.

It will be implemented in four phases.

Phase one, which is underway, involves the construction of an 87-metre-high dam wall with a 688 million cubic metres storage capacity, and preliminary works for the implementation of the subsequent three phases.

The second phase of the Thwake Multi-Purpose Dam project will involve the installation of a hydropower generation plant, while phase three comprises the installation of water supply, sanitation, and wastewater infrastructure.

The fourth phase will involve the development of the irrigation component.

The project is being funded with Sh59.95 billion from the government through budgetary allocations and Sh21.94 billion from AfDB.

Thwake Dam will provide water for domestic, irrigation, hydropower and industrial use, mainly serving Makueni County and parts of Kitui County.