Thwake Dam Project Nears Completion at 94.2%

The Thwake Dam project has reached 94.2% completion, according to Principal Secretary for Water and Sanitation Julius Korir. The dam is being built at the confluence of the Athi and Thwake rivers along the Makueni-Kitui border. Once completed, it will provide water for domestic use, irrigation, and electricity generation. The project is expected to improve access to water for farming in the region, addressing the biggest impediment to agricultural potential.

Residents in the affected areas have expressed mixed feelings about the project. Martin Kimeu, a resident of Wote, defended the compensation process, saying he had followed the project since its inception and believed the exercise had been conducted properly. However, some households have complained that construction-related blasting damaged their homes, reporting cracks in walls, windows, and foundations, as well as dust, noise, and ground vibrations.

In August 2026, residents from villages in Mavindini Ward sought an independent review by the African Development Bank (AfDB) due to alleged construction-related damage. The residents claimed that some properties had been left out of assessments and compensation. The AfDB conducted a field mission to the project between September 21 and 25, publishing its report on October 21, 2026, which identified outstanding health, safety, environmental, and social issues.

The AfDB's report called for timely compensation and continued monitoring of the project's environmental and social performance. The bank's team, led by project task manager Nancy Ogal, met residents whose homes had been affected by blasting. The government has secured additional funding to complete the project after experiencing cash-flow constraints. Korir stated that the government engaged with development partners, who allocated additional funding to support the project's completion.

In June 2026, the AfDB approved additional financing of €68.39 million to support completion of the first phase, alongside funding from the Kenyan government. The financing will support engineering refinements and safety works, including strengthening foundations, raising the dam, and constructing two additional saddle dams. The project has four phases, covering hydropower generation, water supply and sanitation infrastructure, and irrigation.

The dam is approximately 80.5 meters high and has a planned storage capacity of 688 million cubic meters. Once the water supply component is operational, the project is expected to provide 150,000 cubic meters of treated water daily to an estimated 1.3 million people in Makueni and Kitui counties and Konza Technopolis in Machakos County. The irrigation scheme is designed to cover 40,000 hectares, equivalent to about 100,000 acres of agricultural land.

The project is also designed to generate 20 megawatts of hydropower. The water supply, irrigation, and hydropower components require infrastructure beyond the dam structure, including treatment and distribution networks and power generation facilities. The government targets April 2027 for water impoundment, marking a significant milestone in the project's completion.

Key points

• The Thwake Dam project is 94.2% complete, with the government targeting April 2027 for water impoundment.
• Residents have reported construction-related damage, prompting an independent review by the African Development Bank.
• The project will provide water for domestic use, irrigation, and electricity generation, benefiting an estimated 1.3 million people.