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PROJECT

ALA RIVER REHABILITATION PROJECT

The African Leadership Academy in Honeydew, Gauteng, is a pan-African educational

facility and leadership development institution. Its mission is to transform Africa by
educating young people to address the continent’s current and future challenges.

Project Team
Client: The African Leadership Academy (ALA)
Landscape Architect: Newtown Landscape
Architects (NLA)
Environmental Engineers: Chris Brooker &
Associates Specialist Engineers (cba)

The timber bridge designed by Chris Brooker is aesthetically pleasing as well as functional, providing easy access for students and staff.

he campus, originally an old printing school, is surrounded by residents) from flooding and delay storm water runoff into the river
spacious grounds, at the bottom of which is a stream which with four detention ponds on the site. In addition, no fauna species
Thad become degraded over time. Johan Barnard of Newtown were to be disturbed or harmed during the construction phase.
Landscape Architects was appointed to head up a team to:
• redesign the river course and surrounding landscape; Barnard says that although landscaping was undertaken, the
• develop the rehabilitation plan; emphasis was on the stream rehabilitation to increase biodiversity,
• conduct environmental and water use studies and applications; and as well as the construction of a timber bridge across it. These two
• monitor environmental concerns for flood control and stream features are the now the focal points of the green open space. “The
rehabilitation. aim was to make the stream more accessible, more aesthetically
pleasing and safer for the students, and to add to the overall
A stipulation of the brief was the assessment of the quality, quantity attractiveness of the campus,” he explains.
and flow direction of surface water to protect the water course and
existing stormwater facilities from undue flooding, damage and In the environmental assessment process undertaken by NLA,
erosion. Facilities upgrades and flood control measures also involved Barnard explained that the river’s flood lines had been incorrectly
the following: calculated and that any construction had to be at least 30 metres
• construction of vehicular river crossing for maintenance purposes; away from the river. “Rivers in general do move naturally, however,
• construction of a pedestrian bridge for student access; and as a result of our rehabilitation work, its position in relation to the
• construction of a system of weirs (11 in total) to limit erosion; campus building has been rectified. It was initially 19 metres away
• continuing with the upgrade of the of the stormwater management from the campus building and is now 32 metres away.”
system and the rehabilitation of the stream for flood control; and
• re-vegetation of the stream and riparian buffer zone. During the rehabilitation process, soil was removed to reduce flooding
and sluice gates were installed to handle the capacity of the river. This
The main reason for upgrading the storm water management system also ensures that the perimeter fence remains intact during normal rain
and stream rehabilitation was to control flooding. The site receives storms. (It previously needed major repairs after most downpours). The
storm water from adjacent properties and the previous stream and construction of stone walls and weirs has helped to reduce the gradient,
infrastructure were not sufficient to manage the amount and velocity and storm water ponds have slowed down the water flow.
of the storm water. The stream had been eroded over many years
and was overgrown with invasive alien species which contributed Specialist engineering
to the flooding. A stipulation of the brief, and an important aspect Chris Brooker & Associates provided specialist input on the following
of the rehabilitation work, was therefore that all alien and invasive aspects of the project:
vegetation was to be removed and replaced with indigenous material • flood modelling and floodline determination for the degraded and
only, in order to bring about an improved ecological environment. overgrown floodplain;
Indigenous wetland species have been planted to attract birds, • conceptual and detail design of the re-shaped and stepped stream to
insects and wildlife – all needed to sustain a small ecosystem. The meet NLA’s brief within the morphological requirements of the water
plan also had to help protect the extended infrastructure (and course and the client’s budget; n

Landscape SA • Issue 123 2023 15