Samba-Caju Water Retention (Earth Dam)

Angola, 2020

Water

Project story

The Sambu Lucala water retention project is meant to enable irrigation of 1295 hectares of field crops in the Samba Lucala farm. It includes a 12.5-meter-high earthen dam and a reservoir with a capacity of 3 million cubic meters of water. Seven diesel-powered pumps move the water through a treatment plant with coarse screen filtration and automatic back-flushing, then through an underground pipe network

that feeds 23 central-pivot irrigation systems, each covering an area of between 40 to 65 hectares, each with its own dedicated fertilizer tank.

The project includes its own independent power center and a wireless control system, enabling efficient operation by local staff.

The process

Challenge

This project required major earthworks to be carried out in a remote area, including the transport and installation of heavy-duty electromechanical systems.

Approach

The water retention project was designed for low-maintenance, long-life operation by local personnel.

Solution

Owini helped make adaptations to local crop planting patterns in order to achieve maximal benefit from the new center-pivot irrigation system.

Some numbers

SDGs we followed

3· 6· 10

Good health and well-being• Clean water and sanitation• Reduced inequalities

Earthen dam Hight

12.5 m

Water reservoir

3M CBM

Enabled irrigation of field crops

1.3K ha

Some numbers

SDGs we followed

3· 6· 10

Good health and well-being• Clean water and sanitation• Reduced inequalities

Earthen dam Hight

12.5 m

Water reservoir

3M CBM

Enabled irrigation of field crops

1.3K ha

In conversation
with Shaul Oren

Shaul Oren is Owini’s CTO.

Part of my job is to oversee the design and planning of Owini’s projects, and to provide engineering support during construction. In coordination with the designer and various consultants, we aim to define in detail the project’s desired outcome, supervising the entire process until a final planning folder is in place. It’s a very interesting and complex challenge, which sometimes includes resolving the contradictory agendas of the various parties involved. Effective communication among designers, consultants, suppliers and subcontractors is essential.

Sometimes, we have to re-think our approach. Initially, we designed the pumping station with large diesel engines that rotate generators which, in turn, feed electrical motors that rotate the pumps. But high cost estimates prompted us to revise the concept so that the diesel engines directly rotate the pumps. This simplified the system, saved significant capital expenditures and decreased projected operating expenses. Owini’s approach stresses on-time and on-budget delivery. The dam and irrigation system were designed to have a very long lifespan. Furthermore, this project will create many new employment opportunities for people in the area.