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RESTORATION AND REHABILITATION FEATURE

The goal with the riparian rehabilitation
initiative was to maximise the resilience
of the urban channel in response to
a rapidly changing upstream urban
environment. Some of the key objectives
were to:
• stabilise the embankments through a
bio-engineered approach;
• source and establish indigenous
and locally adapted plant species to
maximise stabilisation; and
• clear and remove alien invasive shrub
and tree species from the riparian zone.
The larger, regional vegetation type
associated with rivers in the Gauteng
region is Highveld alluvial vegetation.
Past agricultural impacts as well as rapid
urban expansion and development
has significantly altered Gauteng river
reaches from their historic condition.
It was therefore decided that the
Hartbeestspruit rehabilitation should Before and after views of a section of the Hartbeestspruit project
focus on representing the important
taxa commonly associated with Highveld
alluvial vegetation. In addition, the
Hartbeestspruit was identified as a highly
urbanised and/or artificial channel or
stream, and emphasis was placed on re-
establishing robust riparian vegetation
that could withstand the extremes
between high and low flows.

The work area stretches the entire length of
the Hartbeestspruit, running through the
UP campus from Jan-se-Gat to the outlet
at the N4. Bulk earthworks have removed
about 21 000m of invasive kikuyu grass
2
from the riparian embankment. Although
rehabilitation efforts in the form of seeding
and planting of historically local plant
species have started between Jan-se-Gat
and Farm Dam, recuperation is still in the
early phases and requires continuous
management. A challenge to an urban
waterway is the infestation of kikuyu, but
Servest has managed to successfully re-
establish veld grass.
Avi-faunal census
Prior to the original rehabilitation
process, the Sustainability Division at
UP started an avi-faunal census, having
noted an improvement in the number Life Northern Gauteng (BLNG). The will move in, indicating further that the
of bird species identified. The initial bird Department of Facilities Management rehabilitation of the Hartebeestspruit has
census was triggered by the proposed then approached this group just before been successful. New species observed
rehabilitation of the Hartebeestspruit. lockdown in March 2020, and it was include the Gabar Goshawk, the Goliath
agreed that whenever a bird census was Heron, Brown-hooded Kingfisher as well
With the re-establishment of the locally planned, BLNG would be advised. The as a Neddicky. New species not ever seen
indigenous vegetation, it was hoped that purpose of this event was to register as along the Hartebeestspruit have started
this would attract avi-faunal species to the many bird species as possible in order to return to the area and there has been
area (birds of a specific region or period). to create a data base for any bird census an increase in species associated with
Initially, the bird census events were held events planned for the future. Similarly, riverine biospheres, namely the Willow
to establish which species were available at the Hillcrest sports campus, birders Warbler and African Reed Warbler. This
prior to the rehabilitation, but it then record species and numbers to compare is very positive in terms of the success of
became a seasonal event where summer annual and seasonal changes. the rehabilitation of the urban riverine
and winter species were compared. ecosystem.
General comments and the census data
The original event at Hartebeestspruit indicate that the rehabilitation has been Information and photos supplied by servest
motivated some UP staff members very successful, and numbers will now Landscaping and the Department of Facilities
interested in birding to approach Bird slowly start to stabilise. Predator species Management, university of Pretoria. n

20 Landscape SA • Issue 112 2022