Ministries & State Agencies / Ministry of Water – Athi Water Works Development Agency
Services Provided by Cadreatech Professionals
Cadreatech provided multidisciplinary engineering support across design review, site supervision, and contract administration. Our role focused on structural safety, construction quality, and technical compliance throughout the project lifecycle.
Construction supervision
Design review and technical compliance assessment
Contract administration
Measurements and preparation of interim and final payment certificates
Project Background and Strategic Importance
The Karimenu II Dam, water treatment, and bulk water supply project is a strategic national water infrastructure development implemented under the Ministry of Water through the Athi Water Works Development Agency. The project was developed to increase bulk water storage, expand treatment capacity, and improve reliable water supply.
As demand grows in Kiambu County and surrounding regions, reliable water infrastructure becomes critical. Therefore, this project plays a central role in supporting domestic supply, institutional demand, and regional economic growth. In addition, the dam improves long-term water security and strengthens flood management capacity.
Because of its scale and public importance, the project required strong structural oversight, strict quality control, and coordinated construction supervision across dam works, hydraulic structures, and water treatment facilities.
Dam Engineering and Structural System
The main project component is a 54-metre-high rock fill dam designed to safely retain large water volumes. The dam also accommodates geotechnical, hydraulic, and seismic considerations. Cadreatech supported engineering review and construction supervision to ensure stability and compliance with approved standards.
First, the team monitored embankment zoning to confirm that materials were placed in the correct zones. Next, engineers verified layer thickness and compaction levels. In addition, they checked material quality during placement.
Rock fill dam construction demands close control at all stages. Therefore, Cadreatech also reviewed the integration of reinforced concrete elements within the embankment system. This included interface behaviour between rock fill, filters, and concrete structures. As a result, the dam achieved reliable structural performance and long-term durability.
Reinforced Concrete Hydraulic Structures
The project includes several reinforced concrete hydraulic and control structures. These elements required precise detailing and careful execution on site. Cadreatech provided engineering oversight for the following:
A 46-metre-high reinforced concrete intake tower for controlled abstraction at different reservoir levels
Approximately 500 metres of 5-metre-high reinforced concrete diversion culverts for river diversion
A downstream valve chamber for controlled water release
A 300-metre-long reinforced concrete spillway for flood routing
Reinforced concrete box culvert bridge crossings to maintain access
Each structure was designed and supervised to resist hydrostatic pressure, uplift forces, and dynamic water loads. In addition, durability provisions addressed long-term exposure to water and environmental conditions. As a result, the hydraulic structures provide safe and reliable operational performance.
Water Treatment Plant and Bulk Supply Infrastructure
A major project component is the 70,000 cubic metres per day water treatment plant. The plant processes raw water from the reservoir into potable water for bulk distribution. Cadreatech provided structural engineering review and supervision for key treatment units, including:
Horizontal sedimentation tanks
V-type rapid gravity filtration units
Backwash pump house structures
A 5,000 cubic metre reinforced concrete clear water tank
A 1,000 cubic metre backwash lagoon
A 1,200 square metre sludge drying bed
Each unit required liquid-retaining concrete design. Therefore, engineers focused on crack control, watertightness, and durability. In addition, the team verified reinforcement detailing and construction sequencing. As a result, the structures achieved long-term serviceability and leakage control.
Auxiliary Buildings and Support Facilities
The project also included several reinforced concrete buildings that support dam and treatment plant operations. These facilities improve operational efficiency and site management. Cadreatech supervised structural works for:
Administration building
Workshop and maintenance facilities
Generator room
Switchgear room
Guard house
Each structure was designed for durability and functional performance. In addition, layouts were coordinated with plant operations and service routes. Therefore, the facilities integrate smoothly with the wider water infrastructure system.
Construction Supervision and Contract Administration
Cadreatech played an active role in construction supervision and contract administration throughout the project. The team ensured that all works followed approved designs and specifications.
Site engineers inspected formwork, reinforcement placement, and concrete quality before and after casting. In addition, the team verified construction sequencing and safety practices. Measurements of completed works supported interim and final payment certification.
Furthermore, Cadreatech coordinated technical queries between contractors, engineers, and the client. As a result, the project maintained technical compliance, quality standards, and steady construction progress.
Outcome and Long-Term Engineering Value
Cadreatech’s structural input ensured high hydraulic efficiency, structural safety, and durable concrete quality across the dam, spillway, intake structures, diversion culverts, and water treatment facilities. Finished levels were achieved accurately, and construction quality met project standards.
As a result, the completed project delivers reliable bulk water supply, improved flood management, and long-term operational resilience. The Karimenu II Dam project demonstrates Cadreatech’s expertise in dam engineering, reinforced concrete hydraulic structures, water treatment infrastructure, and professional construction supervision for state agencies in Kenya.
Our process includes detailed planning, material selection, precision machining, assembly, and multi-stage quality inspections. This structured approach allows us to complete projects on schedule while achieving outstanding accuracy, durability, and compliance with industry regulations.
Site Preparations – Excavations & Dam Axis Grouting Works
Construction phase showing site preparations at Karimenu II Dam, including foundation excavations and dam axis grouting works carried out to improve foundation stability and control seepage prior to embankment construction.
Geotechnical Investigations and Logging
Geotechnical investigation and soil logging activities carried out at Karimenu II Dam to determine subsurface conditions, bearing capacity, and suitability of foundation strata for dam and reinforced concrete hydraulic structures.
Spillway and Dam Embankment Construction
Progress photo showing the construction of the reinforced concrete spillway and the rock fill dam embankment at Karimenu II Dam, highlighting large-scale earthworks, concrete placement, and hydraulic structure integration.
Completed Works and Dam Filling Ongoing
Completed dam structures at Karimenu II Dam with reservoir impoundment underway, marking the transition from construction to operational phase and confirming structural stability and hydraulic performance.
Water Treatment Plant Facilities
Water treatment plant facilities constructed as part of the Karimenu II project, including reinforced concrete sedimentation tanks, filtration units, clear water tanks, and supporting infrastructure for bulk water supply.
Aerial View of Staff Residential Areas
Aerial view showing staff residential housing constructed within the Karimenu II Dam project area to accommodate operational and maintenance personnel, supporting continuous site management and long-term operation of the dam and water treatment facilities.
