Page 7 - LandscapeSA_116v2

View of the iconic
switchbacks from
the top of the pass

deviations. This included widening the stained and applied to all the culvert The road design did not conform to
road, the re-alignment of sections where inlets and outlets, bridge structures and standard road specifications as it is
the existing road could not accommodate protection barrier walls. located in a World Heritage Site and
the design curves, new bridges, stormwater the EIA required that the existing route
culverts, the stabilisation of cut embankment Revegetation and rehabilitation had to alignment be followed as far as possible.
and slopes, and the rehabilitation of accommodate vegetation changes due to A very specific area was the construction
disturbed areas within the road reserve. altitude. This required that vegetation had of the road though Yellowwood Corner,
to be harvested from the same general which contained several protected plants
Issues directing the design solution area as the rehabilitation. To achieve this, including Yellowwood trees and smaller,
Initially the local community was against plants were rescued from the construction rare plants right at the edge of the original
the project, especially the tour guides, as area and housed in a nursery in Howick, gravel road. The new road was then
the attraction of the pass was largely due maintained until needed and then designed to be narrower at this point and
to its ruggedness. Right from the start, an replanted on site. Several species were the side drains were re-designed to fit
attempt was made to interact with and grown on in the nursery for later re-use. through the space without damaging the
include their specific requirements by Grass seed and sods were harvested from vegetation. A few of the rocks had to be cut
identifying spots along the route where areas adjacent to the works area. back to accommodate the new road. The
they would usually have stopped. Lay-bys exposed cut rock was then stained with a
were introduced, and the road slightly The success of the rehabilitation and product called Permeon to blend it into the
widened to accommodate their vehicles. revegetation was due to the combined untouched adjacent rocks.
advice of rehabilitation specialist Alex
The weather played a large part in the March of Nkosi Nursery, and renowned To compound matters, the existing narrow
design solutions as it could vary from botanist Elsa Pooley, an expert on the plants road had to remain open throughout the
freezing in winter with snow and ice, to and vegetation of the Natal Drakensberg. construction period to provide access to
high temperatures and high rainfall in traffic, mainly 4x4 Toyota taxis ferrying
summer. Initially the design of the concrete Slope stabilisation varied according passengers to and from Lesotho, tour
structures was to have been stone cladding to geology, which in turn varied from guides and general traffic.
to match the original stone walls. However, sandstone to mudstone, basalt and loose
due to the huge temperature variations, talus slopes. This dictated whether slopes Previously, the original road at the start of
the stone cladding would have popped off could be just topsoiled and vegetated, Section 1 cut through the historic Good
due to uneven expansion and contraction. first stabilised with geofabric, topsoiled Hope Trading Site, which for many years
The final design was to develop shuttering and vegetated, stabilised with gabions or was a place to wait for transport up and
with a stone finish mould which was then reinforced with anchored shotcrete. down the mountain. As part of the heritage

Landscape SA • Issue 116 2022 5