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ENVIRONMENTAL ARTICLE

View downstream from foot bridge
in Fourways Gardens 2018. Sediment
accumulation can be attributed to poor
construction management practices
during the widening of William Nicol
Drive.

One of the weirs on the stream in
Fourways Gardens. Great care was
taken by Earthforce not to damage
existing trees along the watercourse
when reshaping the banks. Kikuyu
encroachment was unavoidable.

process relate to the topography and with Brooker on this project.
geology of a natural river or stream. In Bruma (Lake) Park, the renaturalisation
of the Jukskei involved demolition of
The renaturalisation of the stream on the dam wall and draining of the lake
the Fourways Gardens property initially which had become a cesspit, and the
involved the rehabilitation of an erosion rehabilitation of that portion of the Jukskei
donga with vertical sides. This comprised by civils contractor Basil Read in 2014/15.
reshaping, stone-lining and planting Landscape architect John Drummond
of marginal species in the riverbed and selected the plants, many of which were
channel edges. Vegetation of sandbanks provided by environmental consultant
was allowed to establish naturally. The Paul Farrell. The river course is protected
size of boulders used was determined with boulders to a depth of about 1.2m,
by the gradient and great care was taken from riverbanks into riverbed. A large area
to create a diversity of habitats through, covered with Cynodon lawn serves as a
voids between boulders to provide homes amongst other features, a series of small floodplain and provides a smooth flat area
for crabs and resting places for fish, and waterfalls and plunge pools, riffles and for recreational activities.
the substrate required for caddisfly and ‘stones in current’. Further upstream on the
other insect larvae. He says that another property, a series of weirs was created to Stones and boulders came from the
important habitat is known as ‘stones in trap sediment, guard against erosion and Gautrain construction rock dumps, and
current’ which is simply water running allow for flooding onto lawn areas. Johan sediment from the lake and a basement
over the surface of boulders. All of these Barnard of NLA and Earthforce landscape excavation was used to rebuild the
considerations in the renaturalisation contractor, Jiri Pechous, were involved

Landscape SA • Issue 91 2019 27