Page 17 - Landscape-Issue124

PROJECT

A historic stone retaining wall integrated into the design of the entrance court ramps and steps
Delicate Indigofra flowers and foliage provide a
submission. All of this, together with a design collaboration that respects delightful aspect to the canteen court
TKLA’s monthly tree reports which formed the landscape architectural lens. As a
part of the site meetings and minutes, landscape architectural, architectural, and
reinforced a commitment to protecting engineering intervention, the SOE project process; Topfell continued these treatments
the trees. As the trees form part of the is an example of how interdisciplinary and monitored the watering process
heritage landscape of the campus, collaboration, from the conceptual phase throughout.
approval of the building proposal and of the project through to the completion To help protect the trees during the
relationship to the trees was required of construction, can enable a sensitive building process and limit access to them,
from the City of Cape Town Heritage and considered working within existing the following steps were taken:
Branch. landscapes. • hoarding was installed around all the
As the building is located between the trees;
slopes of the UCT cricket oval and the Landscape installation • access to the tree protection zones was
retained trees, there was a concern that Stephen Steyn from Contours Group only permitted via gates with locks;
the ground water filtering down from says they were privileged to have been • signage and information regarding the
the oval into the root zone of the trees involved with the landscape installation protected areas was displayed.
would be obstructed by the building’s of this project. “In terms of the landscape The excavation of the basement and
footings. Trees have set soil heights architecture, it required in-depth analysis footings impacted on the tree roots, and
required around the base of their trunks, and working around the trees, which are Topfell was contracted to prune, protect,
as well as sensitive root systems that existing and non-movable assets that had seal and trim the roots, and stabilise
spread extensively below the surface. to be preserved and protected. The TKLA steep embankments with sandbags. They
On a sloped site where earth is to be team attended diligently to this, as always. covered exposed roots with heavy duty
cut into to provide large flat surfaces By the time we put spades into the ground, plastic sheeting to prevent contamination
for the building, TKLA’s job became they had already smoothed the way for our from limestone in the cement, which
particularly difficult. They observed the installation.” would have a negative effect on the trees
existing contours and drainage patterns as it changes the pH of the soil. A top
to improve the retention of surface water On site arborist grade soil/compost mix, rich in nutrients
in the landscape. Further design of the As the arborists, Topfell’s role was to prune, to regenerate the roots, was used to
stormwater pipes and cut-off drains lift and undertake tree surgery on all the backfill the excavations once the building
around the building facilitated subsurface trees located at the educational site to work was completed. Says Sean Maasch
irrigation of the entrance trees. accommodate the extensive building work. of Topfell: “The heritage trees are thriving,
Planting was made possible by the They built dams around the bases of all thanks in no small part to how well TKLA
spaces carved out through the design the trees as changes in earth levels would managed the entire operation.”
process and knitting the precinct re-direct the natural water source from the
together, providing entrance ways in upper slopes that these trees use to survive. Green Star Certification
some parts and escape routes in others. This enabled them to feed the trees with Francois Retief of Sow and Reap, the green
The mass beds include seasonal bulbs as fertiliser, slow-release pellets, compost and building consultant for the project, guided
a means of marking the changing seasons mulch. They also painted the trunks with the design team in alignment with the
within the landscape, while shade-loving tree paste and used ingredients, similar certification scheme operated by the GBCSA
groundcovers were used as a way of to a steroid, to feed the trees, build their (Green Building Council of South Africa).
introducing colour in the shadows of the immune systems and enrich the soil. The The project received a 4-Star Green Star
tree canopies. trees responded extremely well to these As-Built certification, which assessed the
The School of Education exemplified treatments during the two-year building building against criteria including energy

Landscape SA • Issue 124 2023 15