Thwake Dam project 94pc complete as residents seek review of blasting claims

Thwake Multipurpose Dam, which is 94.2 per cent complete, with the government targeting April 2027 for water impoundment.[File,Standard]

Thwake Dam is 94.2 per cent complete, with the government targeting April 2027 for water impoundment as residents seek a review of alleged construction-related damage claims.

Principal Secretary for Water and Sanitation Julius Korir told the National Assembly Departmental Committee on Blue Economy, Water and Irrigation that construction had reached 94.2 per cent.

The dam is being built at the confluence of the Athi and Thwake rivers along the Makueni-Kitui border. It is designed to provide water for domestic use, irrigation and electricity generation.

Martin Kimeu, a resident of Wote, said the project would improve access to water for farming in the region.

“Ukambani is fertile. Water has been the biggest impediment to the realization of our agricultural potential. Thwake Dam water is the clear solution to this,” he said.

Kimeu also defended the compensation process, saying he had followed the project since its inception and believed the exercise had been conducted properly.

Jacob Mwanzia, a resident of Madangi Village, said households in his area had been assessed and compensated. He argued that outstanding complaints should be addressed without delaying the project.

Mariam Mwikali, another resident, said assessments had been conducted on affected properties and residents given an opportunity to raise concerns.

However, some households have complained that construction-related blasting damaged their homes. Residents have reported cracks in walls, windows and foundations as well as dust, noise and ground vibrations.

In August 2026, residents from villages in Mavindini Ward, organised under the Thwake Dam Blasting-Affected Community Committee, sought an independent review by the African Development Bank (AfDB).

The residents alleged that some properties had been left out of assessments and compensation. They also sought access to assessment reports, photographs, measurements, valuation records and estimates for repairs or reconstruction.

A project official said the dam's safety department invited competitive bids for an independent assessment of properties potentially affected by blasting. Agile Consulting was selected to conduct the exercise.

The official said the consultant assessed 330 households within a two-kilometre radius of the construction site and submitted its report to the project implementation team. A large proportion of those assessed were satisfied with the exercise, the official added, without giving a breakdown.

Ben Mwongela, a director at Agile Consulting, said the assessment reviewed blasting records, vibration data and compliance with regulatory standards.

The exercise also involved documenting households, classifying structural defects and preparing bills of quantities and cost estimates for repairs or reconstruction, he said.

The AfDB conducted a field mission to the project between September 21 and 25, with its report published on October 21, 2026.

The bank's team, led by project task manager Nancy Ogal, met residents whose homes had been affected by blasting and identified outstanding health, safety, environmental and social issues, including homeowner grievances.

The bank called for timely compensation and continued monitoring of the project's environmental and social performance.

During a stakeholder engagement visit to Mavindini in October, Korir said the government had secured additional funding after the project experienced cash-flow constraints.

“When we ran short of cash, we engaged with our development partners, and they allocated additional funding, and this money will now go towards total completion of the project,” he said.

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 bank said the financing would support engineering refinements and safety works, including strengthening foundations, raising the dam and constructing two additional saddle dams.

The project has four phases. The first involves construction of the dam, while the subsequent phases cover hydropower generation, water supply and sanitation infrastructure, and irrigation.

The dam is approximately 80.5 metres high and has a planned storage capacity of 688 million cubic metres.

Once the water supply component is operational, the project is expected to provide 150,000 cubic metres 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.