Contents
of August 2003
EDITORIAL
The issue of sustainability
UPFRONT
News
IDENTIFYING INVADERS
Indian Shot and Australian
Silky Oak
LETTERS
Trees and the city
TREE OF THE ISSUE
Geoff Nichols chooses the Marula
FEATURES
Expansion
of LignoTech SA reduces Sappi Saiccor's waste stream
Taking precautions to save trees
Demonstrating an alternative
building technology
Beyond the conventional
A sacred place under siege
Mitigating the ecological
impact of river works
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EDITORIAL
The issue of sustainability
Sustainability
is a complex issue. It can be very simply described as a state in which humankind is
living within the carrying capacity of the earth. But there is nothing simple about it.
The challenges are enormous.
The third
highly successful conference in the series on Sustainable Built Environments, entitled
‘Technology and Management for Sustainable Building’, was held at the CSIR in
May and at that conference Jeremy Gibberd of CSIR’s Division of Building and
Construction Technology gave a list of sustainable development objectives, looking at the
three legs of sustainability – environmental, economic and social. The first
objective he mentioned was the need to ensure that development conserves or increases the
size, biodiversity and productivity of the biophysical environment.
At the same
conference, in an admittedly delightful presentation largely about his ‘twin
thin-skin construction’ method, Gerald Gordon, a Research Fellow at Wits University,
asked why we use our precious fertile farmland for housing and ignore the infertile rocky
slopes which are in plentiful supply, explaining that because of temperature inversion
living on a hillside is also healthier than living in a valley. He added that sloping
sites with poor gardening soil generally offered superior foundation support and
stormwater dispersal was easier.
Gordon has
clearly not taken into consideration that rocky slopes and ridges support biodiversity.
Our quartzite ridges in Gauteng, for example, are a vitally important natural asset,
providing habitat for high numbers of plant and animal species. Gauteng’s Department
of Agriculture, Conservation, Environment and Land Affairs (DACEL) in their policy to
protect Gauteng’s ridges says that they are of vital import as future refuges for
biodiversity in an urbanised landscape (see UGF Sep/Oct 2002). They may be relatively
infertile but they are rich in natural diversity, form vital habitat for many threatened
species and serve as natural wildlife corridors which promote ecological processes. Many
streams originate on ridges and ridges control water input into wetlands. They provide
aesthetically pleasing environments for the surrounding inhabitants and serve as nature
reserves attracting tourists and recreational users.
Also, do we
necessarily want to disperse our stormwater? Architect Peter Rich told Leigh Darroll, when
she interviewed him about designing with dry-stacked, earth-cement blocks, considered to
be environmentally appropriate (page 26), that in Australia every site development plan
has to have, as an integral part, a rainwater management and conservation plan. Retaining
and utilising stormwater or ensuring, through soakaways, that the water is used to
recharge aquifers is surely of importance in our water scarce country? Rich says that
environmental consciousness needs to permeate through from the property developer to the
building inspector.
He warns
that we should, however, be careful of the ‘hype’ surrounding green architecture
which seems to make it something exceptional, because all architecture should respond to
climate and the context of its locality (see page 27). But then again there is something
exceptional about using seawater as a means of cooling a building, which is what has been
proposed for the new headquarters of bp Southern Africa (see page 30), and the brief
generally called for a “beyond the conventional” office environment aimed at
delivering sustainability.
Professor
John Smallwood of the Department of Construction Management at the University of Port
Elizabeth says that client associations and the institutes supporting those involved in
designing the built environment need to evolve environmental goals and accelerate the
implementation of interventions to protect the environment. He adds that the
construction/building industry needs “...to prepare for the changed nature of items
it will be required to design, construct and manage, new materials it might have to use
and the processes it will have to adopt”. He feels the industry needs, through its
boards and associations, to be proactive in its contribution towards environmentally
related efforts and issues.
Although UGF
concentrates largely on urban issues, every now and again there is a really special story
set in a rural area, and the possible demise of the relatively little known Lake Fundudzi
in Limpopo Province is, we believe, deserving of our attention (page 34). After all,
sustainable principles apply across the board. The environmental protection the lake has
been afforded in the past because of its cultural and mythical status is worth noting, as
is the attempt being made, currently, to spread environmental awareness in the area to try
to save the lake from silting up.
The story of
the white crocodile is a story that, according to local chieftain Ntsandeni Netshiavha, is
based on reality. He says these crocodiles do exist but that they are lazy creatures and
also not easy to see. They are the crocodiles that protect the shrine of Lake Fundudzi.
The lake is considered sacred because it is inhabited by ancestral spirits. He says that
these light-skinned crocodiles have never attacked a human being, although dogs have been
attached. It is easy to imagine that they would, however, have acted as a deterrent,
protecting the lake against over-fishing, particularly frightening away outsiders who were
unaware of their relative harmlessness. According to Professor Ben van der Waal of the
University of Venda, a light coloured crocodile was actually photographed in 1990. The
light colour is ascribed to the water quality and possibly to a limited form of albinism.
The
spiritual beliefs of the Vhavenda people who live in the vicinity of this exceptional
fresh¬water lake are gradually being eroded away and the respect previously shown the
lake is dwindling – exposing it to more and more careless treatment and consequent
environmental degradation.
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UPFRONT
Permaculture
project at youth correctional facility
The
objectives of Food & Trees for Africa (FTFA) are to contribute to greening,
sustainable natural re-source management and food security. FTFA’s recognition of the
need for sustainability is reflected in the growing number of permaculture projects that
it facilitates. Support from The Green Trust, a partnership between Nedbank and WWF-SA,
has allowed FTFA to employ a Green Trust Permaculture Officer for the past nine years and,
amongst numerous other community based projects, Joe Matimba’s expertise has helped
inmates of the Emthonjeni Youth Correctional Facility in Baviaanspoort outside Pretoria to
establish a highly productive vege¬table garden based on permaculture principles.
Permaculture
means ‘permanent agriculture’ and represents a method of food production which
integrates ecology, landscape and other environmental factors with organic gardening,
creating a sustainable method which produces more energy than it uses and recycles all
nutrients and waste.
Emthonjeni
is a state funded youth prison and school for about 700 juvenile offenders from the ages
of 15 to 21. The permaculture project was initiated in 2001 and the third mixed crop of
high quality vegetables is now ready for harvesting. Crops have included beetroot,
cabbage, spinach, cauliflower, tomatoes and carrots, with chillies growing in between the
other vegetables as a natural pest control.
The initial
team of inmates that produced the first crop under the facilitation of Matimba is now
teaching fellow inmates how to work the land according to permaculture principles. They
are learning about soil amelioration and that thorough mulching suppresses weed growth and
retains water, and that there is no need to use chemicals for pest control. The young men
are learning skills that will stand them in good stead when they leave the prison and the
permaculture project is now part of the prison’s rehabilitation programme, along with
skills such as arc welding, carpentry, spray painting, panel beating and brick laying.
The
vegetables are donated to needy members of the surrounding communities, such as old age
homes. The project is also intended to help develop a sense of self worth amongst the
inmates. The vegetable donations serve as a kind of apology to the community – the
action helps to heal the wounds of crime.
Contact Joe Matimba at FTFA. Tel: (011) 803 9750. Email: info@trees.org.za
The end of the
much-criticised Braamfontein bridge!
Henning
Rasmuss wrote a critical commentary for the third issue of Green File, as it was known in
its inaugural year – 1996, in which he called the ill-conceived steel footbridge at
the Jan Smuts Avenue entrance to the inner city, “Braamfontein’s Bridge of Sighs”.
With the
welcome demise of the footbridge, presumably as part of the Braamfontein public open space
renewal and the opening of the splendid Nelson Mandela bridge further down the road, we
thought it would interest readers to recall what Henning said at that time – and UGF
should, in fact, look again in a forthcoming issue at the ongoing billboard scourge which
continues to change the visual texture of Johannesburg. Nothing much has changed. He said:
“What this structure represents is the appropriation for commercial gain of one of
the few dramatic entry points into the city centre by outdoor advertisers.” And their
clients are just as guilty!
Henning went
on to say: “Let us disregard for a moment the shapelessness and sheer crudity of this
inelegantly constructed piece of backyard engineering that has been given pride of place
at one of the gateways to Johannesburg. My concern here is not with form but with the
spirit behind its appearance. Great cities are partly made so by the interaction of their
landscape with the buildings in it. The City of London has even gone so far as to register
its skyline as a trademark. Vistas in a city are important for orientation and for a sense
of identity. These vistas are fragments of the collective image of a city.
“The
Jan Smuts Avenue entrance to the inner city was just such a critical point in our built
and natural landscape. It has been irreversibly spoilt by the provocative insertion of an
advertising billboard camouflaged as a pedestrian bridge. And it is certain that this is
only the first of many such invasions to come: it would seem that the Metropolitan
Planning Department is quite willing to sell off the visual rights of our city to the
highest bidder....... Do we have a right not to have advertising forced on us at every
turn? A drive down any major road in Johannesburg would indicate that there is no such
thing as reasonable control.”
The City,
and/or the large corporates in Braamfontein, have been able to rid us of this blot on our
landscape and UGF looks forward with interest to the results of the Braamfontein corporate
precinct rejuvenation project. Fortunately, Henning, the damage was not irreversible!
Woollen
insulation product developed in UK
Christine
Armstrong, a sheep farmer’s daughter who knows the value of the natural fibre, has
developed an innovative use for wool during a period when the UK wool industry is
struggling. Manufactured in the UK from unwanted home¬produced wool, Thermafleece –
produced by Armstrong’s company, Second Nature – can be used for roof, wall and
flooring insulation. The wool is from hill sheep farmed throughout the UK which have
coarser fleece that is in less demand by garment manufactureres. The wool is used to
create a non-woven product with excellent insulating properties.
Malcolm
Campbell, commercial director for Woolmark, comments on the natural attributes of wool:
“It’s anti-bacterial, ultraviolet protective, naturally insulating and
fire-retardant. My cousin in Scotland got so little for his fleeces that he would burn
them: it wasn’t worth the fuel it took to take them to market. The wool industry has
got to rally and market itself. The key is that you’ve got to innovate.”
Armstrong
adds: “We have not developed Thermafleece as a cheap alternative to other insulation
materials such as glass fibre. It fact it costs significantly more – but its
advantages are its ecologically sound nature and the extra benefits wool brings to a
building’s environmental performance, including summer cooling, winter warming and
condensation control. Wool is hydroscopic: it is able to absorb and de-absorb moisture. It’s
fantastic in buildings with condensation or old timbers.”
Because
Thermafleece does not irritate the skin, eyes or respiratory tract, no protective clothing
is required during installation. The product is also totally recyclable and its useful
life is predicted to be in excess of 50 years.
Website: www.secondnatureuk.com
Health study for
South Durban Basin
The study,
which has been approved by the Executive Committee of the eThekwini Municipality, will
extend over a period of 18-24 months and will comprise an epidemiological study and a
health risk assessment. According to the Deputy Minister of Environmental Affairs and
Tourism, Ms Rejoice Mabudafhasi, the health study is part of the Multi Point Plan (MPP)
initiated by government in 2000 to find a sustainable solution to the poor air quality in
the South Durban Basin and for the implementation of which she bears responsibility.
Key project
areas of the MPP include the establishment of a modern air quality management system, the
undertaking of the health study to characterise exposure levels, setting air pollution
standards, phasing out of dirty fuels in an attempt to reduce sulphur dioxide pollution
and the managing of future emissions. The University of Natal was awarded the tender to
conduct the health studies.
Dr Mike
Sutcliffe, municipal manager of Durban Metro, said that it was intended that the study
would determine how industrial air pollution is affecting the communities in the basin and
surrounding areas, the severity of the exposure and, most importantly, what steps should
be taken to ensure that people living in the basin are guaranteed a safe and healthy
environment.
There has
already been much progress since the introduction of the MPP three years ago: the Vehicle
Emission Strategy is in its final stages; the National Standards for Priority Pollutants
will be launched within a year; The National Air Quality Management Bill is due to become
law at the end of the year; air pollution by-laws for the Durban Metro are in their final
stages of preparation; and leaded fuel will be phased out by 2006.
Mabudafhasi
emphasised the strategic importance of the South Basin health studies, the first on such a
large scale and context to be undertaken in South Africa. The results drawn from the
studies should provide insight into the health status of other communities in SA exposed
to elevated levels of industrial and vehicular pollution.
Contact Zodumo Mbuli of the Office of the Deputy Minister of DEAT. Cell: 084 680 7860.
Tel: (012) 310 3899.
Johannesburg NOW:
Sao Paulo International Biennale
Johannesburg
has been invited to participate in the Fifth Sao Paulo Biennale exhibition of Architecture
and Design, as one of seven world cities with different problems and different contexts,
under the theme Metropolis. This comparative exhibition will take place over a two month
period starting on 13 September 2003 at Sao Paulo’s Ibirapuera Park, designed by
world renowned architect Oscar Niemeyer. Johannesburg will represent the African continent
and is the youngest of the chosen cities, while New York and Sao Paulo will represent the
Americas, London and Berlin will depict Europe, and Tokyo and Beijing will serve as
examples of Asian cities.
Henning
Rasmuss of Paragon Architects who is one of the curators of the exhibition, along with
professional curator Meredith Randall, says that the brief is simple: “Show us
Johannesburg, is what we have been asked to do. We are going to be displaying the city
– the good, the bad and the ugly – in the context of how cities happen. We have
put together a team of people to tell the story of Jo’burg over the last ten years,
against the background of its history. This year’s Biennale is based on questions
about the quality of life of the urban dweller (consumers of architecture) in cities
across the world. We aim to present a complex and positive image of Johannesburg, based on
honesty about the past and commitment to the future.”
The Sao
Paulo Biennale is a big tourist event and over 300 000 visitors are expected. The event
has, over the years, gained critical acclaim in the international architectural press and
in academic circles and is supported by workshops and fora for public debate which cater
for city planners, administrators, developers, professional consultants and members of the
public.
Johannesburg
has been allocated 32m x 9m of exhibition space and this will be the setting for a series
of banners, wrapped in a time line showing how the landscape has changed over the past 115
years of Johannesburg’s history from veld to forest, illustrating the human and
architectural content of the city over the decades, with the last ten years of phenomenal
change in the new democracy predominating. Urban landscape photography, videos, plans and
maps and models of current and proposed developments will be presented through banner
technology. The exhibition will celebrate Johannesburg as a dynamic city responding to its
key challenges.
Government,
private sector and community initiatives will be covered: including Constitutional Hill,
the Alexandra Renewal Project, Newtown and other inner city market and housing projects,
the upgrading of taxi ranks and public space, the Gautrain, Melrose Arch, Montecasino, the
Gold Route, the proposed Freedom Route, the Art City project, Sophiatown community
activist projects, road closures, land grabs, informal settlements, the history of
hawkers, immigrants, the homeless and children in Johannes¬burg – and displays of
artefacts and products in the form of sculptures, crafts, recycled objects, books and
music, conveying the cultural and historical richness of the city.
A travelling
exhibition
It is hoped
that if funding is forthcoming, the Sao Paulo Biennale will trigger a travelling
exhibition and that after closure in Brazil in November, Johannesburg NOW will travel to
Berlin and from there to New York in March 2004 and then on to London where it will be
part of the Ten Years of Democracy celebrations hosted by the South Africa Embassy. It is
envisaged that Johannesburg NOW will return to SA in time for a number of showings to
celebrate a decade of democracy – this will possibly involve an extension of the
exhibition to include architectural projects from across the country. Partnerships are
being sought on a national basis.
Johannesburg’s
Municipal International Relations Policy adopted by the Council in August 2001 is an
example of how partnerships with other cities can allow for the exchange of knowledge,
promotion of tourism and furtherance of good governance – and it is hoped that
Johannesburg NOW will serve as a vehicle to cement these international partnerships.
The offices
of Paragon Architects are functioning as the vibrant production centre for the exhibition
and students from the Department of Architecture at Wits University are hard at work with
Professor Lindsay Bremner and Mpho Matsipa participating. Thorsten Deckler, who
co-authored (with Henning Rasmuss) the project on Johannesburg for the Venice Biennale
2000 (see UGF Jul/Aug 2000), along with Stephen Nasoo and Mudney Halim, who run a
community history and development organisation in Fordsburg, also form part of the dynamic
Johannesburg NOW team which is constantly growing and changing to include all those who
want to be identified with the future of the city.
Contact Henning Rasmuss. Tel: +27 11 482 3781. Email: paragonarc@icon.co.za
SALI Awards of
Excellence 2003
This year 85
projects countrywide were entered into the South African Landscapers Institute (SALI)
Awards – of these 29 entries received Gold Awards and 14 Silver Awards. Landscape
architect Peter Dayson once again served as the national co-ordinating judge. The regional
judges in the Cape were landscape architects Clare Burgess and Beyers Theron; in
KwaZulu-Natal landscape contractor Pam McGlone and Natal Technikon lecturer Ashleigh
Goodbrand did the adjudication; while in Gauteng, where a mammoth number of 51 entries was
received, the following panel of six judges did the honours: landscape designer and
lecturer Lynton Johnson, environmental journalist Carol Knoll, landscape designer Gordon
Smith, nurseryman Roy Trendler, landscape architect Johan Barnard and nurserywoman Andrea
Hepplewhite.
Dayson
commented that 54% of the potential gold and silver winners (excluding the projects
entered under maintenance or specialised turf) were either predominantly or totally
indigenous in their choice of plant material. He made particular mention of the Courtyards
of the Civic Centre in Cape Town which were designed by a botanist and installed by Eco
Creations, representing the different biomes found in the Cape and illustrating the
appropriate use of indigenous plant material. He said that he was particularly impressed
with the standard of construction work in a number of the winning projects: Garden of the
Senses at the Durban Botanic Gardens and all of Blok Designs other entries; Broadacres
Garden Centre and Heathway Shopping Centre by Greenacres Landscapes; and House Brink by
Eksklusiewe Tuine. He added that the following projects were worthy of mention for their
innovation, logistics and planning: Lejwe La Metsi Game Farm and Extreme 16 by Worth It
Landscaping, Indigo Bay and Pemba Beach by Emerald Landscapes and, once again, House Brink
and Garden of the Senses.
The joint
overall winners of the SALI Shield for Excellence in Landscaping were Blok Designs for the
design and construction of Garden of the Senses and Real Landscapes for the construction
of the landscape at the Mpumalanga Legislature in Nelspruit, which was designed by KWP/NLA
Landscape Architects. Dayson considered the former to be a groundbreaking design with
excellent construction and timeous completion within an extremely tight schedule (to be
ready on time for the Botanical Garden Congress held in Durban last year). The latter, he
said, was an exceptional undertaking in landscape construction following closely behind
the main contractor, with exceptional attention to topsoil conservation and management and
the protection of the natural environment. Garden of the Senses also won the Parks &
Grounds Trophy for the best in-house design and construction.
The Rand
Water Trophy for the Best Waterwise Project was won by the Top Turf Group for the
construction of the Classic 9 hole par 3 golf course, Inanda Greens in Johannesburg,
designed by Robert O’ Friel Golf Design (see Nov/Dec 2002 UGF). The Evergreen Gardens
Novice Trophy was won by first time entrant Capescapes for The Peninsula Phase 2 Parergon
which was designed by Waterfront Landscape Architects. Mention was made of the project’s
attention to detail, the excellent quality of the plant material and structures, and the
management of the project.
The
following were the other Gold Award winners.
Lejwe la
Metsi Game Farm in the Waterberg was constructed by Worth It Landscaping and designed by
Patrick Watson. Dayson commented that the contractor showed great initiative in the
interpretation of the designer’s vision. Two further Gold Awards were achieved by
Worth It for the Health Spa at Mount Grace in the Magaliesberg, a highly innovative design
by Patrick Watson where the contractor was commended for the excellent stonework and
general commitment to the project; and Extreme 16 (the Leadwood Tree) designed by
Eksklusiewe Tuine in Sandton. House Brink was designed and constructed by Eksklusiewe
Tuine and was appraised as being an outstanding example of close co-operation between the
architect and the landscape designer, achieving a completely integrated home and garden;
while House Mulder designed and constructed by the same company was considered to have
some very interesting detailing and a fabulous vegetable garden.
Blok Designs
won four further Gold Awards for the design and construction of House Matthys at Zimbali
Lodge, which Dayson considered to be an outstanding development in the new African ethos
in landscape design – completely in sympathy with the natural surrounds; 4 Royal
Palms, 525 Currie Road, and Willingdon Hall in Kloof.
In the
‘specialised turf’ category, Emerald Landscapes were commended for their
exceptional ability at the Gary Player Country Club in upgrading a working golf course
with minimal disturbance to the players, without compromsing standards and attention to
detail; while the Top Turf Group was commended for its excellent maintenance of the same
course. Dayson said that the mature appearance of the elements of the Morningside Golf
Course in which Emerald Landscapes were involved attested to their excellent preparatory
work and ground works; while Evergreen Gardens were commended for a quality product and
installation work on the same course near Koster in the North West Province.
Emerald
Landscapes won another two Gold Awards for their projects in Mocambique, Pemba Beach and
Indigo Bay – both designed by Patrick Watson. Although the judges were unable to
visit the actual sites, Dayson commented that it was clear from the contractor’s
computer/video presentation that an excellent standard had been achieved at these remote
sites.
Aside from
the SALI Shield, Real Landscapes won two further Gold Awards for a Private Residence in
Hyde Park, Johannesburg, designed by Environmental Design Consultants and Pearl Valley
Estate near Paarl designed by Planning Partners. In both projects the excellent growth of
the plant material attested to good soil preparation and plant selection. The latter
project utilised predominantly indigenous plant material and achieved marked success in
very exposed conditions.
Greenacres
Landscapes won Gold Awards for Broadacres Garden Centre in Fourways and Heathway Shopping
Centre in Blackheath both designed by Gouws Uys & White and House Ball designed by
Shirley Wallington. The latter project was considered to be an excellent interpretation of
the designer’s concept, while the two former were particularly noteworthy for quality
paving, water features and other built structures.
Further
winners were Grun Art Designs for the design and construction of Studio Courtyard in
Pretoria, considered by Dayson to be a very original concept; Countryline Landscapes for
Sasol Polymers in Bryanston designed by Christine Walker, which manifested excellent
attention to detail and good tree selection; Eco Creations for Cape Town City Civic Centre
designed by Eco Logic, where the sourcing of unusual plants was commended; Plantcare
Landscapes for the maintenance of the Holiday Inn Garden Court on the Marine Parade; and
Langverwacht Landscapes for the design and construction of Villa du Sud in Somerset West,
where the interesting juxtaposition of indigenous and exotic plant material was considered
noteworthy.
Contact Val Wamsteker of SALI. Email: val@sana.co.za
The burning
question of biofuels
The UK hopes
that one of the ways in which it will achieve its commitment, under the Kyoto Protocol, to
reduce its CO2 emissions by 12,5% below 1990 levels by 2010, is to make use of
biofuels. Biofuel is organic matter burned in energy stations to produce heat or used as
fuel to drive machinery. Heat production is used to warm rooms or converted into
electricity. Because biofuel only releases the CO2 it has absorbed as it grows,
no additional CO2 is released into the atmosphere when the fuel is burned
– unlike burning fossil fuels.
Fuel sources
are many and varied. Malcolm Chilton, commercial director of Energy Power Resources Ltd
which has five biofuel power stations with a total power output of 108MW, making it the
largest biofuel power generator in the UK, says: “At the moment we have targeted
waste. Very little effort has yet gone into growing biofuel crops in the UK.”
The use of
vegetable and animal oils to run diesel vehicles is increasing, with the government
reducing tax on vehicle biofuels. Most biodiesel in the UK is composed of used cooking
oil, following the pattern of using waste products as biofuel. Chilton says that
agricultural waste is still plentiful with straw being used as biofuel and woodchips from
forestry the next to be targeted.
Companies
such as Wood Energy can build systems capable of producing 15kW of heat (enough heat for a
three or four bedroomed house) through to systems generating 5MW (enough energy to heat a
small town). Dr Robin Cotton, managing director of Wood Energy, which designs and installs
heat-only systems says: “It is very modern, high-efficiency technology. It is using
CO2 neutral technology, displacing fossil fuels and creating woodland. Woodland
should ideally be grown near the heating plant. The advantages are the reduction of
greenhouse gases and self reliance. The job connection is local in nature so it is
advantageous to the local economy. If you are producing woodchips two miles down the road,
that’s less fossil fuel from the Middle East. This is a major industry in almost
every other European country. There are probably half-a-million automatic biofuel systems
in Europe. Wood Energy has installed about 20 in the UK.”
Hugh Loxley,
technical director of Bical, which is developing uses for miscanphus, a grass originally
from Asia and now a vital biofuel, says he believes future biofuel use will be based on
micro energy generation. “In reality, we are taking a step back about 80 years, when
everyone used to heat their homes with wood, but we are doing it in a modern, efficient
way.”
Text by Carl Appleby. Website: www.eprl.co.uk
The Green Trust
Awards Winners in 2003
The Green
Trust Awards which were launched in 1991 recognise organisations and projects that are
making a significant contribution to the environment. The Green Trust was founded in 1990
as a mutual benefit partnership between WWF-SA and Nedbank. This year the Department of
Environmental Affairs and Tourism (DEAT) has joined the Awards partnership. The Awards are
adjudicated by a panel of independent judges, representing a broad spectrum of
environmental fields.
Manager of
The Green Trust, Thérèsa Brinkcate, pointed out that the Awards specifically recognise
initiatives that are both innovative and sustainable. “Many of the finalists achieve
remarkable results with extremely limited resources,” said Brinkcate, in praise of
the numerous individual and community based projects that were submitted this year.
The honey
badger was chosen as the ‘motif’ for the 2003 Awards, as it exhibits the same
qualities of tenacity that are in evidence in the work of the finalists and winners. In an
effort to protect this threatened animal, The Green Trust has helped to promote badger
friendly practices through a national project.
Overall
winner: established project – Eastern Cape Estuaries Management Programme. This
project which works with local communities and contributes directly to the improved
conservation of six estuaries is run by the Institute of Natural Resources. It is involved
with the implementation of conservation-orientated management plans, land use planning,
the education of stakeholders and the provision of information through handbooks,
newsletters, articles and a website. Contact Duncan Hay. Email: hay@nu.ac.za
Overall
winner: emerging project – Bio-Experience. This project has created a successful
eco-tourism business while contributing to conservation projects by drawing on local and
international volunteer support to work with surrounding communities, assisting with a
wide variety of projects from erosion and invader plant control to the cleaning of cages
and oil-soaked seabirds and assisting with game counts. Most volunteers are international
tourists who pay for a working holiday through assisting with such projects.
Bio-experience – a travel agency with a difference – currently places 40
volunteers a month and aims to double this number by 2003. Contact Natanya Dreyer. Tel:
(021) 557 4942, Email: bioexperience@absamail.co.za
The Natural
Resources Conservation Award sponsored by Lafarge SA was won by the Afromontane Forest
Seed Collection Project under the auspices of Santam/Cape Argus Ukuvuka: Operation
Firestop. Through training residents from the informal settlement, Imizamo Yethu in Hout
Bay, in seed collection and off-site cultivation, the project is rehabilitating depleted
and threatened areas of the Afromontane Forest in the Cape Peninsula Park. (This
innovative project will be covered in detail in a forthcoming issue of UGF.)
The Business
in Action Award sponsored by DEAT was won by the Sandton Convention Centre in Gauteng
which has made a substantial effort to limit its environmental impact over and above legal
requirements, through the management of waste, air quality, water, energy and the use of
chemicals. Suppliers to the Convention Centre are required to conform to its environmental
standards laid down in a comprehensive Environmental Management System. (See background
article in UGF May/June 2001.)
The
Individuals in Action Award sponsored by SA Breweries was won by Jim Morel of Knysna
Estuarine Aquarium and Educational Centre. Morel, through his total dedication to the
cause, has been responsible for raising conservation awareness amongst local business and
the community in the Knysna estuary. The Community Projects Award sponsored by DEAT was
won by Badimong Wetland Rehabilitation Project in Limpopo Province. The school that runs
the project raised community awareness about water issues through the rehabilitation of a
local wetland. The project has also generated employment through the use of wetland reeds
for basket weaving and has supplemented nutrition through a vegetable garden.
The Energy
Savers Award sponsored by DEAT was won by SEED (Sustainable Energy for Environment and
Development). This programme aims to integrate sustainable energy practices into urban
living and implements such practices through partnerships with local and national
government and NGOs. The Environmental Education Award sponsored by an anonymous donor was
won by Learning for Sustainable Living – Birdlife SA. This is an environmental
education programme which is closely aligned with the school curriculum and has published
a resource booklet and organised workshops to encourage extensive teacher participation.
Contact Thérèse Brinkcate of the Green Trust. Tel: (021) 888 2836. Email:
lbrinkcate@wwfsa.org.za
Clean development
mechanism project in Kuyasa, Khayelitsha
A pilot
project, involving eight homes and two crèches, which is working towards global climate
change, has been instituted in Kuyasa, a low-income RDP development in Khayelitsha. The
project, launched by the City of Cape Town in partnership with the SouthSouth¬North
Trust, has involved the installation of solar water heaters, ceilings with ceiling
insulation and energy efficient light bulbs, in order to demonstrate how greenhouse gases
can be reduced through a mix of renewable energy and energy efficiency measures, at the
same time as providing economic and health benefits.
Says
70-year-old Kuyasa pensioner and participant Elsie Tabalaza: “Now things are much
better. Since the ceilings have been installed, it is much warmer than it was before. The
solar water heater is also making a big difference. I don’t have to put water on the
flame or use the electric kettle.”
Clean
Development Mechanism projects, provided for by the Kyoto Protocol on Climate Change, must
reduce global gas emissions and contribute to the sustainable development of developing
countries.
SouthSouthNorth
Project Manager Shirene Rosenberg comments: “This project will demonstrate the use of
simple technology that can reduce energy costs for low-income households by using more
efficient energy sources. The project also provides work in the community and is
increasing workers’ skills, enabling them to gain work experience that will help them
to find further employment.”
SouthSouthNorth
commissioned Cape Town-based Green Energy utility AGAMA Energy to retrofit the households
with the use of local labour. An ongoing study of the energy patterns of those occupying
the 10 retrofitted buildings is underway to document the full extent of savings, both
energy and financial.
The Kyoto
Protocol encourages monitoring of these savings in order to make use of foreign funding
which will enable the City of Cape Town to offset the costs of upgrading these houses
– provided that the project successfully reduces energy use. As a result of the
improvements, a decrease of about R438 per a household per a year, in reference to energy
costs, is expected, which is a huge saving for low-income households, and it is
anticipated that a decrease of about 1,24 tonnes of CO2 per household per year
will be released into the atmosphere.
Developed
countries which have ratified the Kyoto Protocol have undertaken to reduce their emissions
of greenhouse gases, through activities in their own and other developed countries or by
sponsoring activities in developing countries. SouthSouthNorth is a trust which builds
capacity among governments, local authorities and private companies who are in the best
position to reduce greenhouse gasses.
Contact Shirene Rosenberg of SouthSouthNorth.Tel: (021) 425-1465.
Glynn Morris of AGAMA Energy. Tel: (021) 701-7052.
Monwabisi Booi, Environmental Dept, City of Cape Town. Tel: (021) 360-1114.
Msinsi Reserve
celebrates a decade of conservation
The
University of Natal’s Msinsi Nature Reserve on the Durban campus celebrated its 10th
anniversary recently and simultaneously launched the Friends of the Conservancy group. The
establishment of this Friends group will be a major step in the fight to eradicate alien
invasive vegetation in the reserve. At least one tenth of the province of KwaZulu-Natal is
invaded by alien plants.
Through the
dedicated work of the Durban Campus Environment Committee, the eastern campus has become a
model for environmental land management in an urban setting. At the celebration, the City
Council’s environmental manager, Dr Debra Roberts, complimented the University on the
phenomenal resource that they had created in terms of the open space plan for the City of
Durban. She said that the creation of the Reserve was ahead of its time and showed what
could be achieved through partnerships.
The
chairperson of the Campus Environment Committee is Prof Julia Botha, head of pharmacology
at the Medical School, and author of the book ‘Bring Nature back to your Garden’
which has recently been translated into Zulu (see Jan/Feb 2003 UGF page 6). Over the past
10 years, the committee has been involved in rehabilitating the wetland and restoring
coastal forest on the eastern campus. Indigenous landscaping has been implemented on the
main campus, at the Killie Campbell Library and on the Medical School campus. The
committee has also been responsible for instituting environmentally sound planning and
building design, and for a recycling programme.
The
challenge of the western campus now awaits the committee. This project aims to restore the
grasslands and indigenous forest patches through the eradication of invasive vegetation
over the 100ha area. This programme will provide employment for members of the Cato Ridge
community who will assist in the removal of invasives.
-----
IDENTIFYING INVADERS
Indian Shot and Australian Silky Oak
UGF’s
regular column to help with the identification of invasive species that are listed in the
amended regulations of the Conservation of Agricultural Resources Act. Most of the
information is taken from Lesley Henderson’s book ‘Alien Weeds and Invasive
Plants’. For further information contact Working for Water’s Weedbuster Hotline:
0800 005 376.
Canna
indica
This canna
species is commonly called Indian Shot and is a declared category 1 weed (excluding hybrid
cultivars), meaning that it needs to be eradicated. These photographs of the canna, which
is a garden escape, were taken alongside a road through the Alexandria Forest – areas
of which are near-pristine – near the town of Alexandria (and the resort of
Kenton-on-Sea) in the Eastern Cape. The plant’s invasive tendencies were clearly in
evidence here, as it sprawled into the fringes of the indigenous forest. This ornamental
species comes from tropical America and as a result it is abundant and forms stands in the
more tropical areas of SA. Its invasive status is as a potential transformer in SA –
meaning that it is already invading natural or semi-natural habitat and has the potential
to dominate a vegetation layer. It invades riverbanks, moist sites and forest and
plantation edges. The flowers which are in evidence almost all year round are red or
orange with a yellow petal below and the petals are narrow. The green spiny three-valved
capsules split open to distribute the seeds. It needs to be controlled mechanically by
digging out the whole plant including the suckers and rhizomes.
Grevillea robusta
This large evergreen tree which originates in eastern Australia is commonly called the
Australian Silky Oak and is listed as a category 3 invader, meaning that it may no longer
be grown or planted, with its invasive status in SA being that of a potential transformer.
It invades forest margins, moist savannah and riverbanks. The leaves are dark green above,
greyish-white underneath and fern-like, while the flowers are in golden-orange
bottlebrush-like sprays. The tree has been planted extensively in the parks, gardens and
along the streets of many SA towns and cities because of its ornamental and shade value.
The sap of the Silky Oak can cause allergies in sensitive people.
-----
LETTERS
Trees and the city
In a recent
visit to Paris I was, like so many other visitors to the city, impressed by its beauty. It
was spring and the first flush of bright young leaves covered the trees, providing a fresh
green backdrop to buildings and city life. Trees were planted everywhere: lining streets,
distributed throughout parks, casting shade over cafes, and filling odd gaps between
buildings and streets.
Cape Town is
also rated as one of the world’s most beautiful cities. Here again, in its older
suburbs, there is a prevalence of trees. But what about other parts of the vast metropole,
further away from the mountain and the sea, where the immediate environment is dominated
by rows of houses, shielded by ugly vibrocrete, either side of busy roads, where residents
prefer to stay within the safety and comfort or their cars or homes.
Recently, I
was horrified to see what could have been an ideal pedestrian short cut to a local
shopping center, (via a school, a remnant of pine forest and farmland, a dam, and a park)
being cordoned off by a solid 3m high wall. The strip of land seems to be destined for
neglect, as it lies along a drainage line and is probably unsuitable for development.
Can NO-ONE
see the potential of having a beautiful walkway within this strip – where you can
walk the dog, go for a run, send the kids off to school by bike without traffic fears, pop
down to the shop or walk to a friend’s house for a chat? The park, the dam, the
school and forest already exist. By clearing a 3m wide strip along this section, planting
some trees, putting down gravel or grass and a couple of benches, a suburban asset would
be created.
To be fair,
there is a lot more public landscaping happening in greater Cape Town and some of the work
is fabulous. The center islands of most large roads in the Tygerberg area, for example,
are landscaped and look great. However, the attention is on the center island: nobody
walks there, nobody sits there. Why all the effort there? The sidewalk is a barren,
unfriendly space.
One
exception (I hope there are more that I am unaware of), is Brighton Road in Kraaifontein.
The municipality has planted a single row of Yellowwoods on either side of this quite busy
road. They should be commended on their investment. Yellowwoods are not the fastest
growing trees, but they are of South Africa’s most beautiful. They have already grown
into quite substantial trees, converting a rather ugly road into a space that people want
to use and the beginnings of a beautiful green belt.
Town
planners can learn a lot from cities like Paris. Pieces of land unsuitable for development
are transformed into green belts. I walked along a green belt on a narrow piece of land on
the side of a wide road leading into and out of an underpass at a busy intersection. One
or two rows of trees were planted along its length, with benches at intervals and
attractive paving. While I sat on my bench I saw strollers and rollerbladers and people
going to and from work. Many properties opened up onto the green belt.
In other
small ‘bits’ of the city and at the famous Metro entrances there are always one
or two trees. These fill the empty spaces between buildings, softening the urban landscape
as well as providing welcome shade: the trees create comfortable spaces in the city. In
Paris, trees are pruned up and clear underneath, meaning that there is no opportunity for
people to hide or sleep under them.
The parks
and gardens departments are putting together a list of indigenous trees that are suitable
for public open space in Cape Town. Existing spaces such as pavements, stormwater
reticulation zones and servitudes need to be seen as areas with potential for public use,
for pedestrian use.
Loni Drager,
indigenous garden designer and sculptor: timber and concrete outdoor sculpture, Cape Reed
Company.
Trees for Cape Town’s
open spaces
Keurboom (Virgilia oroboides) – small/medium size, colourful in spring,
fast growing, medium wind resistance, hardy.
Wild Peach (Kiggelaria africana) – small/medium size, fast growing, good shade tree,
attractive fruit, wind resistant, hardy.
White Stinkwood (Celtis africana) – medium size, yellow autumn leaves, medium growth
rate, dense shade in summer, medium wind resistance, hardy.
White Pear (Apodytes dimidiata) – medium/large size, medium growth rate, dense shade,
wind resistant, hardy.
Cape Ash (Ekebergia capensis) – medium/large size, medium growth rate, dense shade,
wind resistant, hardy.
Wild Olive (Olea europaea var. africana) – medium size, slow growing, good shade,
wind resistant, hardy.
Common Saffronwood (Cassine peragua) – small/medium size, attractive flowers, medium
growth rate, dense shade, needs pruning in beginning for suitable form.
-----
TREE OF THE ISSUE
Geoff Nichols chooses the Marula
Sclerocarya
Birrea
Durban
horticultural consultant Geoff Nichols, who says he likes to be called a gardener because
that is what he really is, has chosen the Marula as the Tree of the Issue. It is renowned
for its economic value and, as he says, is a wonderful tree for parks. The Marula is
considered by some African tribes to be a sacred tree because of its valuable fruit, used
for making jams, jellies and alcoholic drinks, and its medicinal properties. It is often
the last tree standing near a settlement where other trees have been destroyed for their
firewood or the land has been cleared for crops. Geoff finds it very evocative of the
Lowveld – there is nothing quite like seeing an elephant reaching for the fruit, he
says. He believes that wild figs and Marulas are trees one should always grow.
He
enumerates the values of the Marula in the parks of South Africa’s northern towns and
cities: it provides relatively light shade in summer because of its light foliage and
therefore does not kill the grass beneath it; it is an erect tree with a wide-spreading
rounded crown; it has a clean stem which, he says, appeals to parks managers; and it grows
quickly into a large tree over a period of 6-10 years (you can sit under it after five
years) depending on its locality – it needs to be protected from frost when it is
young. He says it is not a good street tree because it drops masses of large fruit.
He comments
on problems experienced in the greater Durban area with Marulas being stripped of their
bark, because bark decoctions are widely known for their curative properties in the
treatment of diarrhoea and other stomach ailments, and for malaria and diabetes. Geoff
says that during his time with the parks department, he painted the bark with a watered
down, grey-green PVA, that was hardly noticeable, lasted for years and discouraged
stripping.
He advocates
the planting of Marulas in groves or ‘economic woodlots’ in community parks for
the sake of their fruit. He says that the planting of trees which will provide fruit over
a 12 month period will encourage monkeys to live in cities and yet keep them out of
conflict with humans. The whole system benefits from the planting of fruit trees such as
the Marula – small mammals, birds, bats and insects – along the edges of nature
reserves and in bigger parks.
Geoff points
out the kind of life the tree supports. Its large fruit is eaten by big birds such as
Crowned and Trumpeter Hornbills. It provides nesting and roosting sites, while its bark
teems with insect life. He recommends that old, hollowed-out branches should be left on
the tree or tied back into the tree. The tree will support Woodpeckers, Red-billed
Wood¬hoepoes and Barbets and house the Woodland Kingfisher, Greyheaded and Yellowthroated
Sparrows and starlings, along with providing roosting and nesting sites for the bigger
raptors in the Lowveld.
Because the
sexes are separate on different trees, Geoff suggests that nurserymen wait for the first
flowering and then mark the trees so that one of each sex can be bought. Selections have
been made by nurserymen and big fruited trees are now available. The tree is a slow
erratic germinator but it will also grow from truncheons. The tree does best grown in open
ground.
-----
FEATURES
Expansion of
LignoTech SA reduces Sappi Saiccor's waste stream
LignoTech
South Africa originated out of the search for a solution to an environmental concern.
Visibility for divers on the Aliwal Shoal was being affected by effluent from Sappi
Saiccor’s mill, which is discharged into the sea through a marine pipeline. This
effluent comprises a suspension of natural binding agents found in wood and it had also
been affecting foam stabilisation on the beaches of the KwaZulu-Natal north coast.
According to
Sappi, the environmental impact of the effluent was purely aesthetic but the company was
sensitive to this and decided to undertake a comprehensive Environmental Impact Assessment
in 1997. Specialist technical studies were conducted by the CSIR, while the assessment was
co-ordinated by Crowther Campbell & Associates. Community representatives were also
involved in the process which resulted in two very effective solutions.
Firstly,
Sappi Saiccor extended its marine pipeline by 4km, effectively increasing dilution of the
effluent with a vast improvement to diving visibility. Secondly, LignoTech SA was
established to beneficiate lignins normally directed to effluent, which further improved
visibility and reduced foam stabilisation. The expansion at the plant which is on the
coast at Umkomaas further extends the reduction of Saiccor’s impact on the marine
environment.
LignoTech SA
generates significant revenue from a previously unused component of wood, normally part of
the waste stream. Lignins are natural binding agents found in wood which are released
during the pulping process. With the expansion, the plant is now the world’s largest
single producer of speciality lignin chemicals. LignoTech SA is a joint venture between
Sappi, the world’s largest producer of coated fine paper, and Borregaard of Norway,
an international chemicals company. The expansion will also create new jobs which will
benefit the local economy.
The range of
speciality lignin chemicals are the end products of advanced lignin beneficiation
processes, refined over many years by Borregaard LignoTech and these are fast becoming the
environmentally friendly product of choice, replacing more invasive alternatives.
Borresperse Ca SA serves as a very important additive to concrete, making it flow more
easily, keeping it workable for longer and reducing the water required for mixing.
Additive ZA is used in bricks, enhancing their quality and strength, reducing breakages
and shortening the drying cycle.
Dustex is
used for road stabilisation, reducing dust on untarred roads, particularly in mining
environments. Dustex provides an environmentally friendly alternative to traditional road
salt. Lignobond is a binder used in animal feeds, making pellets stronger and easier to
transport. Its inclusion in the manufacturing process can cut electricity consumption by
13%. Lignobond is used in Borregaard LignoTech’s proprietal brand of animal feed,
SoyPass. SoyPass is a soya bean meal feed and the specific speciality lignin chemicals
used in this product accelerate weight gain and increase milk yield in dairy herds.
Speciality
lignin chemicals are also used in tanning, ceramics production, water-treatment, high
performance batteries and as stabilisers in agricultural pesticides. The chemicals are
biodegradable and non-toxic to both humans and animals. About 90% of LignoTech SA’s
output is exported to countries in South East Asia, the Middle East, Australia, New
Zealand and the USA.
The
expansion of the plant will further reduce the suspended and dissolved solids component of
Sappi Saiccor’s effluent stream, while SO2 emissions from the plant are
being kept within the original permitted limitations, despite the 200% increase in
capacity as the plant’s new expansion goes into production. These emissions will
remain steady at 0, 72 tonnes per day. This achievement results from the company’s
additional investment in scrubbers which are designed to remove gas from the plant’s
emissions. The scrubbers capture gas emissions from the plant’s processing tanks
through custom designed vents. The emissions are then sprayed with water, which absorbs
the gas, releasing cleaned air into the atmosphere. The acid water produced in this
process is reused at both LignoTech and Sappi Saiccor.
Use is being
made of local entrepreneurs and one example of this policy is that a local farmer was
contracted to clean the site for the expansion, which had previously served as a ‘knot
dump’ where unusable timber from Sappi Saiccor had been dumped. The local farmer
cleared the knots which he then used to fertilise land for cultivation that had previously
not been arable. Past experience of using knots and bark waste had shown him that this
natural fertiliser improved his crop yield by about 30%. The farmer is now contracted to
remove knots and bark from Saiccor on a regular basis. Other entrepreneurs that have
benefitted from the development at LignoTech SA, have been suppliers of pallets, bulk
packaging and transport. It is estimated that about 380 new jobs will be created amongst
suppliers and buyers as a direct result of the expansion project.
Production
capacity at LignoTech South Africa , as a result of the expansion, has been increased from
55 000 tonnes to 155 000 tonnes per annum. Current annual turnover is expected to treble
once the expanded plant reaches full capacity. The project has received the support of the
Department of Trade and Industry because it is in line with their Strategic Industrial
Projects programme through its value-added components, job creation and inclusion of
SMMEs.
Working to make cars
from 100% recyclable material
A research team at Queen Mary, University of London, is working at turning the
unlikely concept of making cars from 100% recyclable materials into a reality. Led by Dr
Ton Peijs, the group has developed a way of producing a fully recyclable, environmentally
friendly material that could replace the non-recyclable plastics currently used in car
manufacture. Recent EU legislation stating
that new cars must be made of 95% recyclable materials by 2015 prompted the setting up of
the team at Queen Mary.
Dr Peijs
says: “Polypropylene is currently the material of choice for the automotive industry.
However, for many applications such as bumpers and car panels, this material needs to be
reinforced with glass fibres to meet performance requirements. Polypropylene and glass on
their own are both perfectly recyclable but once they have been combined they cannot be
separated, so cannot be recycled.
“Manufacturers
will need to start using ‘pure’ materials that are fully recyclable and low
cost, yet have the stiffness and strength to be effective in car making. Our research team has devised a way of creating a
strong and tough polypropylene that can compete with current glassfibre reinforced
plastic. The pure material is based on polypropylene tapes. The tapes are coated with a
specially formulated thin layer of polypropylene that plays the role of fusing the tapes
together in a compaction process using a hot press. Tapes are then woven into fabrics
which can be made into sturdy sheets by sealing layers of fabric together.”
A further
environmental advantage is that the new material is light in weight and that car parts
will weigh less, resulting in considerable fuel and emissions reductions. One of the team’s
commercial partners is commercialising the technology.
Website: www.qmul.ac.uk
Flexible plastic
furniture from old plastic bottles
The scrap material, high density polyurethane (HDPE), that results from plastic
bottles has been recycled into very usable raw material which has been used amongst other
basic products for the making of plastic block outdoor furniture. This furniture tends to
be limited in its design and the recycled material is generally mixed with an original
product, therefore only a low percentage of waste is incorporated.
Richard
Liddle, a master’s design graduate from Northumbria University in Newcastle, UK, has
undertaken considerable research and developed a technique of moulding and laminating the
material to create curves. He sees the project as being all about saving the planet by
turning what is generally classed as rubbish into something aesthetically pleasing and
valuable. He says this is more than just about furniture, it is about making a statement
about the planet and the way forward.
Thanks to
Newcastle City Council’s initiative to be the first UK producer of this recycled
waste, Liddle has had access to the material for furniture applications. He says that
through his investigation into the fundamental make-up of HDPE, he has been able to create
a process that uses HDPE to its fullest.
His plastic
furniture process takes waste HDPE and machines and extrudes it , enabling it to take on
flexible forms. This flexibility allows the material to be set in moulds to produce a
series of curved forms which can be reproduced continuously and fixed alongside one
another to create a furniture piece of any depth. The process currently uses a high
percentage of waste material and, with new research developments, this could soon be 100%.
This young
designer is now director of his own innovation house, Cohda Design, the aim of which is to
create well-designed niche products and processes that have a reduced environmental
impact. He is developing a range of indoor furniture comprising desk and furniture
products.
Text by Chris Mikami Email: info@cohdadesign.com
SPAR’s Eco-bags
benefit WESSA
On Monday 21 July, the Minister of Environmental Affairs and Tourism, Mohammed
Valli Moosa, presented a R50 000 cheque to the Wildlife and Environment Society of SA
(WESSA) in Durban. Since the promulgation of the plastic bag regulations, SPAR, like most
other supermarket groups, has been selling special long-life bags, known as Ecobags, for
the convenience of customers. When the legislation was introduced SPAR made the decision
to donate a portion of the proceeds from these bags to environmental organisations.
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Taking precautions to save trees
Carol Knoll
spoke to arborist Anton Moller of Arbor Africa about the all too common problem of damage
done to trees, either willfully or unintentionally, on construction sites. Moller was
mentored into arboriculture by the renowned Jeremy Fowler of Tree Care Services. He says
there is no formal qualification in arboriculture in the country but that Technikon SA is
planning over time to introduce a number of ad hoc short courses which will eventually be
developed into a formal course.
Roller says
that more often than not the damage done to existing trees on a construction site is
unintentional and stems from lack of knowledge. People do not know how to protect trees
– an earthworks contractor seldom knows what precautions to take and an arborist is
often called in when it is too late to save the situation. He says that if all necessary
precautions are taken on construction sites, the landscape’s most valuable assets
will have an excellent chance of survival.
Tree
preservation is largely about not damaging the underground portions of a tree. Moller
describes a site in Melrose, Johannesburg, where there were two 50-60 year old Pin Oaks
well worthy of preservation, but by the time he was asked to provide secifications for
their protection, an excavation had been done to within a metre of their trunks and a
metre in depth. With a mature tree this is invariably lethal, as trees have relatively
shallow root systems. In this case, almost the entire root system had been graded away and
the trees had to be felled as they were on the point of toppling. Moller says arborists
have a responsibility to prevent tree failure as part of their professional code of
safety. They are obliged to identify and point out dangerous situations and he deemed this
to be one of those.
Tree roots
need as much air as water. They are therefore concentrated in the top 800-900mm with
virtually no roots below this depth and the bulk of the root growth is in the top
200-300mm. This may vary slightly in certain soil conditions. A very shallow cut into the
soil around a tree removes a large percentage of the root system. Even sinker roots will
be on average only 1m in depth, tapering off fairly quickly – almost wedge shaped in
appearance. In certain soil conditions sinker roots could be deeper. Moller says that far
too often, the root ‘bole’ is perceived by building contractors to be only a
small portion of the actual root system. Under ideal conditions, the root system can
spread as far as twice the height of the tree.
Raising or
dropping the existing level of soil around mature trees is also often lethal. Dropping the
level of soil will remove valuable roots, whereas raising it can suffocate the roots.
Stacking soil up the stem of the tree or even just piling soil on top of portions of the
root system, away from the tree, can cause suffocation. Moller says raising the level by
as little as two inches can be enough to kill a tree. In clayey soil, half an inch is
enough to smother the roots. Raising the level of sandy soil is less injurious but also
often causes problems.
Moller makes
the point that the existing mature trees on site have to dictate soil levels. Roadways
must be designed with trees in mind. He says mature trees are more likely to suffer
because their capacity to adapt to new environments is lessened, whereas younger trees are
vigorous and have a greater capacity for adaptation.
Not all
trees on the site should be preserved. Moller says developers are often influenced by the
sheer size of exotics and that it should be borne in mind that some indigenous trees,
highly worthy of preservation, may be of a smaller size. He points out the beauty of a
Buddleja saligna with its craggy old growth that may be the result of only 15-16 years of
existence, and comments that these smaller trees can sometimes become literally too heavy
with growth and need to be thinned out to save them from toppling. Some trees can be a
liability on a site, either because they are damaged and dangerous or because they are
invasive species that will eventually have to be removed.
Moller
comments on the need for synergy between design and development professionals and
arborists on site. He says it works both ways and cites an example of a problem that could
have been avoided had he personally known how to read the plans correctly. It relates to
work that he was doing on the site of an office complex in Johannesburg where, according
to Moller’s interpretation of the plans, the building footprint was well away from a
particular tree and it looked to him as though the tree would be safe from construction
injury. The actual basement excavation, however, extended well beyond the footprint in a
technique called “batting back” to prevent the wall of the excavation from
collap¬sing onto the building. The tree was threatened by the excavation. Moller learnt
that the building footprint and the extent of the excavation were not the same thing.
In a wealthy
residential suburb of Sandton, he tells of a landscaping project with lovely lawned
terraces and well laid out ponds and an attractive constructed stream, where the levels
around existing trees had all either been raised or lowered. A Plane tree that was about
40 years old had had one half of its root system removed by these arbitrary level changes,
while the other half was being suffocated. The landscaper’s technical knowledge of
trees was clearly not good enough.
Moller says
sometimes one has to destroy trees on a natural site (or a previously landscaped site) to
allow a road to be constructed and then the decision needs to made by the environmental
consultant, well in advance of the construction team moving in, as to which indigenous
trees are worth saving and the road should be routed accordingly. There may be a choice
between destroying ten young trees or one mature tree. The choice is tree specific and
life expectancy needs to be taken into account here. If the mature tree has only 10 years
of life left and the 10 younger trees have 100 years life expectancy, then the choice
should favour the younger trees.
He says,
however, that it depends on the species and the specimen. The shape and general aesthetics
of an ancient Olea europaea may make it well worth saving but it may be misshapen and
singularly unattractive. It is often worth saving younger, better shaped trees. Trying to
save all the trees on a well treed site is often a recipe for disaster because many of
them may well be damaged during construction and protecting fewer would have ensured that
at least these would be healthy. He says we often need to sacrifice something or the
development can’t happen. The point is that tree preservation cannot wait until
construction has started, it needs to be planned and budgeted for.
Preservation
should focus on preventing injury, not fixing the tree after damage has been done.
Compaction problems are the most common unintentional cause of injury. Good shade trees
are at risk because construction vehicles often park under these, and large vehicles
continuously driving in and out of the parking area, over the roots of these trees, can
cause compaction which results in suffocation and crushed roots.
Even
increased pedestrian traffic can cause compaction. Moller tells of the trees in Pretoria’s
well known Burgers Park (winner of the Large Parks category in UGF’s Town¬scape
Millennium competition – see Jul/Aug 1999 issue), where several fabulous old Ficus
trees were threatened because of the increased popularity of the park. By the time Moller
was called in as a consultant, some had already died while others were in decline. He
advised that the compaction should be relieved through vertical mulching – drilling
holes through the compacted layer throughout the root zone and filling these with a porous
growing medium. Another way of relieving compaction is through digging trenches that
radiate away from the trunk and filling these with a porous growing medium. The latter
method, according to Moller, is more effective but more invasive to the existing
landscape.
SA Arborists
Association
The SA Arborists Association was established three years ago and has a
membership of 15 people in Gauteng who attend meetings regularly. The Association is
active and these meetings or seminars are held on a bi-monthly basis and include talks on
subjects such as tree biology, mulching, pruning methods, training of young trees and
safety issues. The Association is for anyone with an interest in trees. The members are
mainly arborists in private practice or street tree managers with municipalities but
growers of trees (nurserymen) and landscapers would benefit from becoming members. The
Association strives to build professionalism in the industry by improving knowledge and
standards in tree care and tree felling.
Arbor Week Events include tree climbing
A seminar will be held at the Education Centre at the Johannesburg Zoo on
Wednesday 3 September. The theme will be ‘Everything you did not know about tree
roots’. During Arbor Week, groups will be taken on tree tours around the Zoo and
problem trees will be identified. Arborists will take part in a tree climbing contest
which will be of good spectator value for the public and a fun climb will be held in which
members of the public can participate.
Contact Bob Carrington Cell: 082 771 7683 or Anton Moller Cell: 083 600
9786.
-----
Demonstrating an alternative
building technology
The new
extension to the Hydraform head office in Boksburg, designed by architect Peter Rich and
built by the owner using its dry-stacked, interlocking, earth-cement blocks, demonstrates
the kind of sophisticated, urban office building that can be created using this
technology. Leigh Darroll spoke to Peter Rich about the building and the Hydraform
building system.
The new
building at the Hydraform headquarters extends the company’s premises from an
existing double-storey house to accommodate a new reception, boardroom, and export sales
office as well as outdoor demonstration areas, and it changes the dynamics of the site.
For
Hydraform, the extension was required to demonstrate the possibilities of building with
its earth-cement blocks – and to answer the questions commonly asked by its clientele
– showing that yes, the dry-stacked bricks are load-bearing, they can be built to
double-storey height (and more), they can carry a second floor of reinforced concrete,
that conventional windows and doors can be easily accommodated and that the system suits
conventional roofing and flooring systems.
Being
owner-built, the new building also served as a testing ground for Hydraform’s
training team – the men who conduct training at sites where Hydraform equipment is
used, to demonstrate how the machines should be operated and how the building system
works.
Speaking of
the design, Rich says, “We needed to change the body language of the building so that
it assumes a commercial presence – instead of being a domestic dwelling masquerading
as offices – and to respond to the automobile scale of Rondebult Road, making a bold
statement and acting as a gateway to Boksburg.
“We
also introduced another material, using structural steel selectively, which adds a
high-tech dimension to the building, in a modest way, and complements the client’s
intention to demonstrate that Hydraform is as suitable to sophisticated urban buildings as
it is to remote rural construction.”
The
extension takes the form of three drums, powerful elements that maximise the building’s
visibility on its corner site near the intersection of the off-ramp from the freeway and
Rondebult Road. Along the business strip that parallels this road, one of the main routes
through Boksburg, most of the former houses have been converted to office premises,
although they remain residential in scale and presence. The Hydraform building is now
clearly distinguished from its residential surrounds.
The
principal central drum, which wraps around the northwest corner of the existing house,
rises to double-storey height and will serve as the new boardroom. The roof of this
element extends from that of the house, which was cut back, and from a new steel box
gutter that marks the break away from the original roofline. It now gestures upward at the
entrance to the building in an unexpected and inviting way. “This accentuates the
change in scale,” says Rich, “and it opens the directors’ offices on the
upper floor of the old house to the northern sunlight.” He makes the point that, in
his view, the roof is as much a generator of design and form as the plan. “The roof
expresses the personality of the architecture.”
The corner
drum, which takes a wider radius and is built to a height of five metres, unroofed,
provides an outdoor enclosure for machine demonstrations. At the approach to reception, a
lower-walled enclosure creates an entrance courtyard.
The
intention is to remove the existing boundary wall to the site, and the sidewalk Syringas,
so opening the property to the street in a generous public gesture but demarcating its
edge with built up planters, bollards and appropriate landscaping. The walls of the drums
and the steel gates between them then establish the security of the building.
The
reordering of the site and the placement of the new elements establish a clear distinction
between public spaces, staff and service spaces.
An
additional office wing extends the premises northward, with the new reception area
creating a link between the old and the new under an extension of the original roof
reaching down from double-story height to single-storey height. The roof bounces up again
over the new office wing, with a wide concrete box gutter defining the juncture between
the roofs. The rainwater runoff collected in this gutter spills into a sump in the paved
and planted entrance courtyard so that the water is returned to the ground table.
Rich says he
encouraged the client to plant indigenous species. “We’re demonstrating an
environmentally appropriate building material,” he says, “It’s important to
be consistent with that in the landscaping as much as in the design of the building.”
Ben Fine,
technical manager at Hydraform who took on the full-time responsibility of managing the
building project, is enthusiastic about the indigenous planting already in place and
additional planting planned on the site.
The standard
220mm wide Hydraform blocks (115mm high and 240mm long) have been used in construction.
The different colours of the blocks – grey and ochre red – derive from the soil
used in their manufacture. All the blocks were brought in from the company’s Midrand
block yard.
The drums
demonstrate how the blocks can be used to build at different radiuses and to a height of
nine metres in the principal drum, dry-stacked except for the foundation and roof-tie
courses. A super-strong adhesive has been used instead of mortar and brickforce in the
roof-tie courses. This adhesive is reportedly strong enough to produce a composite beam
using the Hydraform blocks. The walls are, in the main, not plastered or bagged, so that
the product can be seen from outside and inside. Window and door reveals are plastered, in
some instances, to create a cleaner finish, although the positive and negative interplay
of the interlocking blocks at window edges could be left exposed.
In the
cylindrical wall of the boardroom, pieces of 8mm Perspex have been inserted at random
intervals where small gaps have been made in the blockwork to take the radius of
construction. In the interior, these Perspex pieces, with polished ends, refract prismatic
bands of light. This is an idea Rich borrowed from American architect Wendell Burnette,
who has used Perspex to similar effect in buildings in Phoenix, Arizona.
Other
decorative effects have been created in the blockwork of the smaller courtyard wall where,
for example, blocks are shifted just out of the formal line of the cylinder to create a
play of shadow and light on the face of the wall, or rough faced blocks introduce a
different finish. Overall, however, the effect throughout the extension is one of unity
and homogeneity, in a coherent arrangement of forms.
To the back
of the building, parking is provided against the southern boundary wall and there is a
service yard along the eastern edge of the site, where gravels, sand and other materials
can be received for product testing and development. Hydraform is currently investigating
the potential of using materials like ash and sludge from water purification processes in
building blocks.
Rich sees
this project and this product as part of the broad process that is seeking “to change
the consciousness” – towards a heightened awareness of the environment and how
we can work with it rather than ignoring it.
At the time
of writing, the Hydraform head office was not yet complete; the roof colour was still to
be finalised and finishing touches, exhibition elements and furnishings were to be put in
place. But the building has established a new profile for the company and is a bold
demonstration of what can be done using its products.
About ‘green’
buildings
Although the Hydraform building system can be considered environmentally
appropriate, and the new head office building clearly responds to its environment, Peter
Rich is averse to the term ‘green building’ or even the qualification of
ecologically responsible design, saying that all architecture should respond to the
climate and the context of its locality. This point cannot be argued, except to say that
so much architecture doesn’t. But Rich sees the ‘hype’ surrounding green
architecture as luring practices into marketing themselves as green architects, or
ecological architects. He says he agrees with Australian architect Glenn Murcutt on this
issue and refers to the words spoken by Murcutt when he received the Pritzker Architecture
Prize last year.
Murcutt
warned about the trap of so-called ecological architecture, saying that to be appropriate,
architecture must respond to place. But for the design of a building to respond to
environmental concerns to the neglect of other social and aesthetic concerns, reduces the
design process to an engineering exercise. The result is not necessarily good
architecture. This is because architecture has to do with spirit – and this is the
point that Rich emphasises.
“Architecture
is a synergy of many things,” says Rich. “You cannot produce architecture by
elevating greenness above all other considerations. Architecture may be practical and
environmentally responsive in its design and use of materials and it may resolve
accommodation requirements, but if it is not serving the human spirit – it’s not
architecture.”
Rich goes on
to say that in vernacular architecture, the landscape, the climate, the seasonal movement
of the sun, the direction of the wind and the rain, local, natural materials, are all
generative factors. It was Kenneth Frampton who best articulated the concept of a Critical
Regionalism, which acknowledges the heritage of appropriate design response in the
vernacular and draws upon this tradition whilst contesting new ground, to make the same
thing differently. Rich cites the work of Finnish architect Alvar Aalto as offering
amongst the best examples of this concept made manifest.
He makes
another reference to Murcutt where the Australian architect draws an analogy between the
making of architecture and throwing a brick into the sea. The brick comes to a standstill
once it has reached its exact place in the flow of currents and fresh turbulence created
by its presence. In the same way, the introduction of a building as an extraneous object
into an existing environment, modifies the environment and creates a new order, at the
same time as the building itself is immediately altered by the existing order.
Rich
questions: “How can we as architects ignore the impact we make on the environments in
which we build, or the impacts that the existing environment will have on the bricks we
set down?”
The Hydraform building
system
Hydraform blocks are produced by hydraulically compressing a soil and cement
mixture in a Hydraform block-making machine. The machines are mobile and can be powered by
a diesel engine, an electric motor, or an independent power source. Blocks can thus be
produced on site using soil from the site or nearby. Blocks are produced in strengths of 7
to 8 MPa, with a 10% cement content, and 4 to 5 MPa, with a 5% cement content. Because the
building system is relatively simple, it has the advantage that it can be employed by
unskilled labour, with minimal training and site supervision provided by Hydraform. This
facilitates community involvement and the use of local labour in building.
Since it
began operating in 1988, Hydraform’s main market has been in the export domain. Now
there is growing local recognition of the products’ value. The Hydraform building
system complies with the National Building Regulations of South Africa and is certified by
Agrément South Africa. The blocks have been tested for strength, durability and stability
by both local and international standards authorities. (For more information on the
Hydraform building system, see UGF Mar/Apr 2001.)
-----
Beyond the conventional
The winning
concept amongst six invited submissions for the new headquarters of bp Southern Africa was
prepared by KrugerRoos Architects & Urban Designers working in collaboration with
Green by Design Architects, mechanical engineers Spoormaker & Partners, and space
planners Thinkspace. Eric Noir of Green by Design presented the winning submission at the
CSIR’s recent conference on Technology and Management for Sustainable Building. Leigh
Darroll spoke to him about the concept, which answers to the brief for an environmentally
sensitive office building and draws together a range of possibilities to meet the
specifics of the complementary brief that was prepared by Arup to address aspects of
sustainability.
Site and context
The site is within the V&A Waterfront in Cape Town, adjacent to the
Graduate School of Business and the Breakwater Lodge. Bordered by Portswood Road to the
west and Somerset Road to the south, it stands at a level above the buildings that cluster
around the water’s edge. The land falls eastward from the Portswood Ridge, towards
the waterfront, and there are a number of existing, historic buildings bordering the
Portswood Road boundary that are to be preserved. The site offers views to Signal Hill and
Lions Head, the city and Table Mountain, as well as over the docks.
From an
urban design perspective, it also offers the opportunity to create a soft link between the
Waterfront and the Green Point Common to the north-west. An existing vehicular route which
bisects the site was seen as presenting the potential to create a public thoroughfare
between Portswood Road and the upper basin. Rather than restricting this route to private
access to the buildings at the water’s edge, which would make it a ‘negative’
element on the site, the architects envisage that, as a public thoroughfare, it could
prompt the creation of a public square beside the planned marina in the upper basin.
The concept
proposes an urban green edge to the site – to create the soft link with the Green
Point Common – and dense planting across it, using locally indigenous species, with
the new and existing buildings in effect cut out of this landscape. As well as
ameliorating the bp site – as Noir says, “the planting will hold the topsoil,
absorb dust, reduce noise, and create a cooler micro-climate, among other benefits”
– it is also intended as a neighbourly gesture to enhance this node of the Waterfront
precinct.
Brief
The brief called for predominantly open plan office space of a total of 18 000m2
(12 000m2 and 6 000m2 to be provided separately), although it is not
yet certain that all of this would be taken up by bp. Support and common spaces were to be
limited to a maximum of 15% of the floor area. The parking provision in relation to this
floor area is substantial and would necessitate a basement structure. A further factor of
the brief was that the offices should respond to bp’s ‘beyond petroleum’
culture – calling for a “beyond the conventional” office environment. The
requirement was to create innovative, resource efficient space, that would be economically
sustainable and in line with the vision of the V&A Waterfront.
The
complementary brief, relating to environmental sustainability, specifies required outcomes
on concerns such as reduced energy consumption per square metre, water conservation,
proportionate use of local versus imported materials and fittings, and similar. Noir
points out that the sustainability brief was not prescriptive but opened up the
opportunity to explore how such specifications could be achieved.
Architectural response
The architectural response follows what Noir calls a framework approach to
design. The design principles are established to define the framework; the concept and the
building evolve in response to these principles. He also emphasises that the specific
environmental considerations are deeply integrated with the urban design and architecture.
A host of possible technologies are drawn together to answer to the specifics of the
sustainability brief. The actual implementation of particular options amongst the various
possible responses presented remains to be finalised, as the project progresses, in line
with budget constraints, technological feasibilities, and the client’s fixed or
flexible needs.
The building
is envisaged as a city, to engender the many attributes associated with such a system: a
dynamic organism, enabling structure, identity, social responsibility, interaction,
legibility, hierarchy, layering, public manners, generosity, resource efficiency, vision,
cross-pollination of ideas. Exploration and development of the plan resulted in a building
configured in the form of five fingers connecting to a ‘high street’.
There is a
height limit of three or four storeys within the Waterfront. “In order to accommodate
the required floor space,” Noir explains, “we had to look at a cluster of
buildings. Although a massive block can be considered more environmentally efficient, in
terms of the ratio between the building envelope and the enclosed space, block buildings
on such a scale are typically hostile and the depth of interior space opposes
opportunities for natural lighting and ventilation and excludes natural outlooks. We didn’t
want to go to a width of more than 22m.”
Each of the
buildings in the proposed concept is separated by planted courtyards but linked by the
high street, and would incorporate a central atrium of not more than 15m wide, to allow
for natural lighting and ventilation. Obviously there is a cost consideration here. The
atrium space has to be made to work, to justify its cost against what could otherwise be
office space. The atria introduce opportunities for energy savings, for example, on
lighting, ventilation, heating and cooling, and to create a more hospitable, user-friendly
interior environment.
Response to local
climatic conditions
Taking account of the winds to which the site is exposed, and using the
gradient of the land, the buildings are oriented longitudinally to face south-east and are
placed on the site so that they ‘duck’ to the wet winter north-westerly and
‘stand’ to the dry summer south-easter. This orientation, with transverse
sections that incorporate the courtyards and atria, will allow for the south-easter to be
used to augment the proposed natural ventilation systems. It also reduces the extent of
east and west facades (which would be exposed to the lower angles of the sun).
The
architects are currently working with engineers to evaluate potential heat gains and heat
losses per façade and to optimise ratios of glazing to solid construction.
Roof as dynamic skin
The roof is envisaged as a lattice structure, floating across the component
blocks, that may provide shade or open to sunlight, become watertight, allow for rainwater
collection, support photovoltaic solar panels, or open to ventilation stacks –
responding to the fixed or changing functional requirements of a given zone.
This kind of
multi-functionalism is something that Noir consistently emphasises – a demand to make
the building work in many various and complementary ways, through integral rather than
add-in systems.
Thermal layering
The building is spatially organised to layer different activities so that the
most stable climatic conditions are provided for the workstations, while pause areas,
vertical circulation, services facilities, lobbies and similar are accommodated in the
peripheral zones where temperature swings will be greater. In Noir’s view it makes
sense to use space in this way. “Instead of installing double-glazing only as a skin,
rather separate the panes of glass – to create an intermediate,
temperature-modulating zone – and use this intervening space to house those functions
for which a strict temperature range is not so critical. In addition, the inner glass wall
can be ‘insulated’ by filing cabinets, archives, or storerooms. In this way, the
internal workspaces are better protected from external temperature swings. It’s just
a different way of analysing how we can use space most effectively – how we can make
all elements of the building work to achieve our sustainability objectives.”
Seawater cooling
It is proposed that seawater could be used as a means of cooling the building.
One of the peculiarities of the Cape Town weather pattern is that the Atlantic coastal
water is about two degrees colder in summer (about 14°C) than in winter (about 16°C).
(This occurs, apparently, because the summer south-easter blows the surface water on the
Atlantic coast out to such a distance that where this water is caught again into the wave
cycle to return to the shoreline, it draws in cold water from the Benguela current.) This
will be advantageous to the proposed cooling system in which seawater would be used, in a
process incorporating heat exchangers, to transfer coolness to the interior –
potentially via chilled ceilings from which cool air would ‘drip’ into the
interior space. There are various ways in which such a system could work and these are
currently being investigated.
Rockstore cooling
A rockstore, using rock from on-site excavations for the parking basement,
could be built either within the basement or at the transfer level between the basement
and the superstructure. This concept, used successfully by Arup in its work at the
International School in Harare (UGF Nov/Dec 2000) and subsequently applied in other
projects as well, uses rocks to absorb and store cool night air (during summer months)
that can then be used the following day to flush hot air out of the building and cool down
internal temperatures. During winter, the rockstore accumulates daytime heat which can be
used to pre-heat the following day’s early morning supply air. This system works more
efficiently where there is a high diurnal temperature range of between 10°C and 20°C
– as is typically encountered at low latitude, high altitude locations –
although it has been put to work at the Lynedoch Community Centre at Spier outside
Stellenbosch (UGF Jan/Feb 2002).
Natural ventilation
The design also proposes incorporating thermal chimneys into the atria of the
building. Working with the natural stack effect of rising hot air, the chimneys would
serve as exhaust vents for hot air accumulated in the building and the atria through the
days. At the same time, it is suggested that the thrust of hot air upward could be used to
draw chilled air from the rockstores into the building.
The
mechanics of making such a system work within the overall design of the building still
need to be refined. It would also need to take account of parallel ventilation systems. If
users decide to open their windows, for example, outside air is drawn directly into the
building. (One of the challenges of the brief is that within the open plan office space
there should be provision for individual control over workstation space.) In addition,
there is a proposal that heat gains in the building from the winter sun should be used to
circulate warm air through the building.
Bioactive air filters
for indoor air quality
Another environmental consideration in the conceptual design relates to the use
of bioactive air filters. In this system, the air intake into the building is filtered
through the soil of planters, which removes pollutant particles. Bioactivity in the soil
transforms the pollutants into nutrients for the plants. Noir reports that this system,
developed by NASA, is currently in use in Denmark and its potential application for bp is
being researched.
Thermal desks
The novel idea of capturing the heat generated by computer equipment and either
releasing it to the exterior (on hot days) or using it to warm the interior (on cold days)
is also included in the design proposal.
Centre for the environment
Another suggestion is that, as part of the development, bp could establish a
centre for the environment. This would demonstrate and monitor the advantages of the
proposed building and make the learning curve encountered in its design and the results of
implementation, available to professionals so that they can replicate or improve on these
interventions in the interests of environmental sustainability. It could serve also as a
public information centre and a study centre for students.
Conclusion
Noir concedes that there is no clear route on decision-making to determine
which systems and technologies, or combinations thereof, will be most appropriate in this
building. Computer modelling is being used for design development on many aspects of the
project. However, modelling tends to address different aspects of design in isolation. The
requirement then will be to assess their respective and combined impacts in order to
decide on the best options.
The approach
in this project calls for an integration of the traditionally separate, compartmentalised
engineering and design disciplines. In Noir’s view, it is the responsibility of the
architects to resolve a coherent interaction, or multi-functionalism, that makes the
structural, mechanical and design elements of the building work together, in the most
cost-efficient manner.
“In
addition,” he says, “the building should express these workings, rather than
tucking them away in hidden service ducts and networks.” It is not yet clear whether
this intention of exposing the working systems of the building, in its structure or in
themselves, will be accepted within the design guidelines governing developments in the
V&A Waterfront, although there are arguments in its favour.
The project
is due to go on site by September this year with a scheduled completion date for November
2004. This programme does not allow much leeway for exploration of new technologies and
trial and error adjustments of experimental mechanical systems. Nonetheless, Noir is
confident that the sustainability targets set out in the brief will be met.
-----
A sacred place under siege
Last
December at the time of the total eclipse of the sun, the Mondi Wetlands Project took a
small group of journalists up to watch that singular event in the ‘path of totality’
at Lake Fundudzi in Limpopo Province – the land of the Vhavenda people – and to
visit the forests, wetlands and peatlands related to the lake’s catchment. Carol
Knoll was fortunate enough to be part of that group. The lake is reputed to be the only
true natural inland lake in South Africa – it is unique and sacred. The group stayed
in the royal kraal of Chief Ntsandeni Netshiavha of the People of the Pool, as they are
called, because this clan of the Vhatavhatsindi people are the traditional custodians of
the lake. The journalists were entertained royally by the chief and members of his family,
who were eager to explain the rituals and beliefs relating to their very special lake
– and to show the visitors their heritage.
The party
was led by, as he surely deserves to be called, a true wetlands enthusiast, Vhangani
Silima, the Mondi Wetlands Project (MWP) community wetlands co-ordinator, who is an
Honours graduate from the University of Venda. He specialised in wetlands in his Honours
year, looking at how the traditional beliefs of the Vhavenda had protected Lake Fundudzi.
It is the taboos, he says, and the respect for the spirits of ancestors that have allowed
the lake to survive in relatively good condition, this far. The traditional values are,
however, being eroded and communities can no longer withstand the onslaught of population
pressures on the land, nor the relentless desire to modernise and ‘develop’ in
ways that are seldom sustainable.
MWP
maintains that Lake Fundudzi holds huge natural resource and ecotourism benefits for local
communities, if it is managed sustainably. With this as MWP’s objective, Silima has
been an appropriate facilitator because of his knowledge of the local people and the
catchment area.
Lake
Fundudzi is referred to by many researchers as the only
natural freshwater inland lake in South Africa, which is a country not well
endowed with inland lakes, as Prof Ben van der Waal of the Department of Biological
Sciences at the University of Venda puts it. Fundudzi is believed by the scientific
community to have been formed by a landslide blocking the course of a river and is one of
very few lakes in the world that have been formed in this way. Studies indicate that the
lake could be 20 000 years old. The Vhavenda people believe that a mystical event caused
the formation of the lake – that the lake was formed by the Creator.
According to
Prof van der Waal, who has done extensive research on Fundudzi, the water quality seems
not to have deteriorated over the last 60 years. The lake is fed by three streams, the
Mutale, the Godoni and the Muiladi, draining a catchment of more than 6 000ha, and the
water level fluctuates considerably. Parts of the catchment, particularly that of the
Mutale River, are well vegetated with both indigenous forest and exotic plantations. Many
local people believe its abundant fish stocks to be the main value of the lake. The lake
and its exceptional environment does not enjoy any conservation status.
Threats to the future
of the lake
In a paper written by Van der Waal in 1997, he records that the total area of
the Godoni and Muiladi catchments that has been transformed by human activities is 42%
– grassland and forest have become settlements and maize fields; while the largest
part of the Mutale catchment, including both grassland and patches of forest, has been
converted to pine plantations. Pine plantations have been planted to within 10m of minor
and major streams and have been left to invade the unique Mutale peatbog. Only the upper
part of the Mutale River shows no serious impacts.
Van der Waal
notes that the Godoni River has been subject to water withdrawal and there are small
weirs, roads and bridges, bank erosion, deterioration of water quality, removal of
vegetation, serious invasion of alien vegetation into indigenous riverine vegetation and
the close proximity of agricultural fields to the streambed in evidence along its course.
Fields have been developed on the lower banks of the Godoni River near the inflow into the
lake and patches of forest and swamp burnt and cleared to plant crops and fruit trees.
Some of the maize fields are eroded and adding to the rapid siltation of the lake. The
Govha tributary of the Godoni is the most seriously affected, with three water diversions
for small private vegetable gardens and orchards in evidence. Firewood is being collected
from the slopes directly above the lake, fishing is unrestricted and there is littering
along the edges of the lake.
In spite of
the fact that access to the lake used to be restricted by Chief Netshiavha, in 1995 a road
was built right down to the lake giving access to the lake without any restrictions. Badly
planned and constructed roads in the area have added to the erosion problems in the
catchment which are responsible for the heavy siltation of the lake.
According to
Van der Waal’s research, the sedimentation rate of the lake over the last forty
years, since pine plantations were established in the catchment may be five times faster
than the general sedimentation rate over the previous 1 270 years. This means an annual
addition of 1cm of sediment to the lake bottom. One of the consequences of the inflow of
sediment is that the top part of the lake is already silted up and is usually dry. This
process is expected to continue and intensify with further water abstraction and habitat
degradation.
Van der Waal
has suggested, in the past, that although the rehabilitation of the entire Fundudzi
catchment is required, a start should be made on the Fundudzi wetland. The wetland is not
functioning to its full potential in terms of water supply to the lake, flow regulation,
erosion control, sediment removal and/or retention and nutrient removal and/or retention.
The connection of
spiritual and environmental values
Chief Netshiavha says that many of the stories about the spiritual significance
of the lake have been distorted over the years and some are so far-fetched that he cannot
conceive of their origin. He says the predominant ritual value of the lake to his people,
the Vhatavhatsindi, is as a graveyard or symbolic tombstone – the place of their
ancestors – a holy shrine. Looking after Lake Fundudzi can be equated to looking
after their forefathers. Members of the tribe are firstly buried in the graveyard near the
chief’s kraal and then after a number of years their bones are cremated and their
ashes scattered on the sacred lake.
He says that
in reverence to this sacred place outsiders are required on first viewing Fundudzi to bend
over and look at the lake upside down through their legs. Traditionally, they may not
visit the lake without prior permission from the chief and may not visit it unaccompanied.
It is, the chief believes, the erosion of such traditional values and respect for the
custodians, the Tshiavha clan – the People of the Pool, that has caused the
environmental problems now faced by Lake Fundudzi.
Relatively
recently, roads have given outsiders uncontrolled access to Lake Fundudzi and practices
that are unsound environmentally abound. “People can do what they feel like and this
is not acceptable to us,” says Netshiavha. “We need help, but we need to weigh
our traditional practices of conserving the lake against present practices. If
conservation management had remained in the hands of the Tshiavha people, then we could
punish someone for cutting down a tree. It is a question of ownership – you will look
after what is yours. Essentially, I have the right to take you to court for trespassing.
“We
discourage over-harvesting of the lake by not allowing boats and net fishing on the lake.
Line fishing is acceptable. The roads, however, make the lake accessible to boats and net
fishing. People no longer respect the custodians and do not ask permission from the
Tshiavha to fish in our lake, according to the traditional practice. In times past the
government also respected this. The fish from Fundudzi taste different, they are sweet
because of the soil.
“We
discourage the planting of mealies on peatlands as the practice will wash away the
valuable soil. The peatlands are being burnt. We are trying to prevent fires. We do have
the power to stop fishing on the lake but we can’t stop ploughing on another
chieftain’s land. We need co-operation – in the days of our forefathers there
was co-operation amongst the chieftains around Fundudzi.”
The chief is
in favour of tourism but a controlled tourism. He is against the idea of cars being
allowed to drive straight down to the lake and comments on the badly planned and
constructed roads that have added to the siltation problems. He favours hiking and
horse/donkey trails. He says visitors will need accommodation but that this should not be
located next to the lake. He likes the idea of visitors staying over in the traditional
villages. There should be no nets or boats allowed on the lake and no material collected
from around the lake – stones and dry timber should be left in place. The collection
of water (with a little bit of sand) from the lake as a medicinal or ritual resource has
always been done with discretion and he believes this should be allowed to continue.
“The
Department of Tourism has approached us and we have agreed to the idea of tourism to
create employment and alleviate poverty but the ritual value of the lake should not be
interfered with. The custodians of the lake must have their say – the Vhavenda
culture has a value in itself. Visitors can walk with Vendan guides who will explain the
value of the lake to them and tell them about the conserving of trees and traditional uses
of trees. We must try to keep our conservation standards and to improve the quality of the
environment around the lake when necessary. Maybe we need guards at the lake and a
signboard explaining what is acceptable and what is not. We need to get together with
different people and maybe together we can come up with better ideas.”
The chief
expressed himself as being in favour of a workshop to encourage co-operation amongst the
government bodies, NGOs and the traditional leaders. He felt that there could be
co-operation once again on the land around Fundudzi through proper understanding of ritual
and conservation values and through negotiation. He said the importance of the lake needed
to be explained.
Awareness raising and
capacity building
In April this year, after several meetings MWP held with Limpopo’s
Depart¬ment of Finance and Economic Development (DEFED) and Tshimangadzo Emmanuel
Tshabuse who is the co-ordinator of the LandCare programme which is being implemented by
the provincial Department of Agriculture, a decision was made to hold a workshop to help
build capacity and raise awareness amongst the communities surrounding the lake, with
DEFED spearheading the process. Wide ranging issues concerning Fundudzi and its catchment
were discussed over two full days and the workshop was attended by 68 individuals,
including all the chiefs of the area.
Forestry
issues such as the collection of firewood in the indigenous forests, invasion by alien
vegetation and the use of fire to smoke out bees were discussed by a representative from
DWAF’s regional offices. Chief Netshiavha, who has spent many years in the employ of
the regional forestry department, spoke about the history of the lake, while Christopher
Khorommbi from Water Affairs, who has studied Lake Fundudzi, spoke about conserving water,
encouraging the continued use of traditional methods of water collection. He said water
should be stored in a clay pot and collected from rivers using calabashes. He pointed out
how a rusty tin used for this purpose was a pollutant. Vhangani Silima emphasised the
importance of wetlands and peatlands, how they could be damaged and what could be done to
protect and rehabilitate them. Tshabuse, chief agricultural officer with the provincial
Department of Agriculture, spoke about soil erosion and the use of slope cultivation and
contour planting of vetiver grass to guard against it.
Victor
Netshiavha, the chief’s brother, of the Department of Education Arts and Culture, who
is currently doing his Masters on the spiritual significance of Fundudzi spoke on this
aspect, along with Penny Barnard of Rhodes University who is supporting Victor’s
studies. Prof van der Waal spoke about his extensive research on the current degraded
status of the lake and recommended methods for rehabilitation and protection of the
catchment. He spoke about problems related to erosion in the catchment and the siltation
of the lake, estimating its lifespan and saying that it was on its way to becoming a
marshland with no open water in evidence.
Each village
in the catchment has elected a committee and after the workshop these committees put
together a constitution in conjunction with LandCare and opened an account to hold funds
provided by the national LandCare programme, which are to serve for the further raising of
conservation awareness. LandCare’s extension officers are acting as facilitators and
the training of farmers is being done in all seven of the villages to encourage correct
cultivation methods. The farmers are visiting certain best practice projects in the area,
such as the Koring Koppies LandCare project near Nebo, which will serve as examples to
them, and conservation is always at the forefront. At Koring Koppies, gabions have been
used to restore a wetland and a sustainable irrigation system leads water from the wetland
to community gardens.
Funding has
also been obtained from Working for Wetlands through DEFED and consultants have been
appointed to devise a comprehensive rehabilitation plan. The work of interacting with the
communities is being done by social specialist Graham Engelbrecht of Information Decision
Systems, while wetland ecologist Anton Linstrom is surveying the wetlands that are crucial
to the well-being of the catchment. Silima is working with the consultants because of his
specialised local knowledge. DEFED has appointed Dakalo Mabuda as manager of the Lake
Fundudzi project with back-up being provided by DEFED’s environmental officer Steven
Mugivhi.
The district
manager (Capricorn District) of DEFED’s environmental affairs, Margaret Nemutamvuni,
sent the following email relating to Lake Fundudzi to MWP, saying: “Thank you for
giving this project its life again – we are happy.”
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Mitigating the ecological impact of
river works
What is the
function of a river? Are rivers merely conduits for excess water and for other waste
materials or are they natural features of value? The state of a river is said to reflect
whether a community has lost touch with its environment. These and other aspects of rivers
require careful thought.
The early
European inhabitants of South Africa settled near rivers because they obtained their water
from them and tilled the fertile soils in their floodplains. As the populations grew,
cities developed and the demand for water exceeded the local supply. Water was sourced
from farther afield and the central role of these early urban rivers changed. Instead of
being suppliers of water, the use of these rivers in removing unwanted water or wastewater
became more important. Towns tended to creep onto floodplains, with buildings being placed
on the actual riverbanks.
The
construction of roofs, paths, tarred roads and freeways, pavements and parking lots
greatly reduced the ability of soils to absorb water falling as rain and increased the
runoff from the surrounding land, and rivers were expected to carry more water than
before. In many cases, more water, moving more quickly along river channels, has
necessitated and continues to necessitate, river works such as the construction of
gabions, retaining walls and other bank protection measures to prevent bank and bed
erosion, and to convey water through urban areas more efficiently.
River works
aimed at the efficient transportation of floodwaters from urban areas usually concentrate
on increasing the capacity of the river channel and/or reducing the roughness (resistance)
offered by the channel. The latter is usually accomplished in one of two ways: by ‘smoothing’
of the river bed and banks through the removal of vegetation, bars and other obstacles to
the flow; or by straightening out the channel.
Experience
has shown that from an ecological perspective, there can be several negative consequences
to these sorts of river works, including:
*
faster flows and less
stable habitat, with fewer backwaters and drier river banks;
*
loss of habitat
diversity and less habitat available for colonisation by aquatic fauna;
*
reduced diversity and
resilience of riparian vegetation particularly if meanders are removed. Naturally
meandering rivers have areas of deposition on the inside of bends and scour on the outside
of bends where the flow is faster. The vegetation in the deposition area is different to
that in the eroding area;
*
loss of perenniality
through removal of riparian wetlands and other vegetation, which store water for release
during times of lowflow;
*
erosion of the
streambed that can lead to banks collapsing;
*
in urban areas the
newly exposed substrates (following erosion through faster flows and drying of the banks)
become colonised by exotic plants unless active control measures are instigated.
Thus, much
of the ecological mitigation of engineering measures needs to be directed at making or
keeping streams ‘messy’ by reintroducing structures, vegetation, bends,
meanders, in-channel variations in slope, pools and other variation, which create habitat
complexity and velocity variation in streams.
Many animals
have life cycles that involve exploiting a variety of river habitats during their life
stages. For instance, fish commonly spawn in one part of their habitat (riffles), use a
different part as a nursery area (backwaters) and then disperse into a third area for
adult growth (deep pools). Similarly, during its lifecycle a particular species of mayfly
will use the marginal vegetation and different areas of coarse sediment in fast flowing
sections of the river.
For an
organism to be present in a river, the requirements of all life stages must be met. If
just one part of the cycle is broken, the population will not be sustainable. To attempt
to support the life cycles of as diverse an array of stream organisms as possible, river
works should aim for:
•
habitat diversity in
the channel;
•
appropriate water
quality (such as, controlling of point and non-point source pollution);
•
an appropriate
riparian zone;
•
free passage between
different habitats;
•
connectivity with the
floodplain (floodplain habitats such as oxbows and their special flooded vegetation are
important habitats for some fish and frogs);
•
near-natural
temperature regimes (this can be achieved through maintenance of habitat features such as
pools and riffles, and overhanging riparian vegetation);
•
appropriate natural
variations in flow regimes.
The closer
the river works come to achieving the above aims, the better the resultant ecological
condition of the river. The entire food web is important and each part should be
considered when assessing the potential or actual impact of river works:
*
to have fish, frogs
and birds, you need to have invertebrates for them to eat;
*
to have invertebrates,
you need to have plant material for herbivores and detritivores.
In general,
the following principles are recommended to minimise the impacts of engineering works on
the ecological condition of rivers:
*
maintain the channel
plan form (particularly the lowflow meandering channel);
*
maintain the in-stream
morphology (riffle-pool sequences) and the approximate spacing (5-7 channel widths).
Spacing will not be exact as it is also dependent on resistant features in the river, such
as tree roots, bedrock intrusions and weirs;
*
design for multi-stage
channels;
*
maintain sinuosity by
concentrating major earthworks on outside bends;
*
maximise species
diversity through maintenance of habitat diversity by designing uneven river margins,
maintaining riffle-run-pool sequences and maintaining substratum;
*
where possible,
utilise off channel (floodplain) areas as flood detention areas;
*
ensure bank stability
by maintaining a slope of at least 1:2, and preferably 1:3 to 1:4;
*
revegetate with a
broad band of diverse indigenous riparian vegetation;
*
work from upstream to
downstream;
*
remove all fencing
across the river;
*
minimise the need for
future mechanical intervention.
Multi-stage
canals are common engineering practice. Usually lowflows are contained in a relatively
narrow channel, with higher flows carried by a wider, leveed floodplain. From an
ecological perspective, if river works are being contemplated on a fairly natural river,
it is better to disturb only one side of the channel and leave the other in its natural
state. Alternatively where space is limited, gabions or retaining walls on one side of a
river can be offset by a multistage design on the other. Engineering works should shape
the banks in shallow ‘steps’, which are graded to hold the different floodlines
(such as 1:2, 1:5). Since the banks will be terraced, they can easily be planted.
In general,
the stages should correspond to different components of a river’s flow regime since
these will determine the type of vegetation that will be able to survive at each point.
For instance, the lower stage might be defined by the upper limit of the wet season
lowflows, which would mean that small spate flows could wash over the first level. The
second stage might be defined by the water level during flood events (such as 1:2 year)
and so on. Obviously inundation levels will change in height relative to changes in
channel shape and channel capacity.
Minimising
the impacts of engineering on riverine ecosystems by definition increases the reliance on
‘soft engineering’ options. These have been shown to be extremely effective
options elsewhere in the world and in South Africa, in many cases providing a more
sustainable solution to stormwater problems. However, in order for soft engineering to be
successful it is essential that the ‘basics’ are done properly and are properly
budgeted for. Of these, by far the most important is the revegetation programme following
construction. To avoid subsequent bank stability and erosion problems, a detailed planting
plan should be produced, and adhered to, for each project and planting followed up with
appropriate maintenance and monitoring programmes. Contingency funds are usually included
to provide for re-planting should the initial planting effort not be successful in some
areas. People using, or living next to, rivers should understand the value of the
indigenous plants in maintaining a healthy fauna as well as their ability to restore the
health of the ecosystem.
The
ecological benefits of a buffer of appropriate indigenous vegetation alongside rivers
cannot be over-emphasised. These buffers:
*
absorb nutrients and
sediments contained in water running off the surrounding catchment, thereby buffering the
river systems from activities alongside them;
*
provide corridors and
shelters for semi-aquatic fauna (otters);
*
provide habitat and
food for birds;
*
serve as the base of
the food-chain for aquatic fauna;
*
protect against
erosion by slowing water in the immediate surrounds, by binding soil with roots and at the
same time facilitating deposition that cleans water;
*
reduce wind strength;
*
trees provide shade
and flowers provide variety;
*
soften the impact of
hard engineering constructions.
In places
where space is limited and the creation of a multi-stage channel is not possible, all is
not lost and with a little effort it is still possible to provide some habitat and
buffering through the establishment of appropriate vegetation in gabions, by providing
spaces between the rock fill for the insertion of plugs. The spaces are lined with a
geotextile for instance, to form ‘pots’ that are filled with a mixture of
organic material and soil. Coarse vegetative material covered with good soil can also be
used on top of the gabions and planted with appropriate plants to reduce the unnatural
outline of the gabion.
Once
construction actually starts, the subtleties are applied, such as the creation of
irregular channel margins to facilitate the formation of backwater areas, and the
necessary care is afforded to the works during construction, such as minimising the
footprint of disturbance by heavy machinery. The result will have a marked affect not only
on the overall impact of the river and its appearance, but also on the rate and degree of
its recovery. A little extra effort in rehabilitation will have a longer-lasting positive
effect on the stability and health of the river as a whole.
Finally,
after construction is complete and the desired landscape forms have been created and the
plants have all been planted, the community should take ownership of the river to see that
the plants survive, that the fauna are allowed to live unhampered by man and his
activities, and to ensure that the river and its banks are kept free of pollution.
Ultimately, a river is there for the community to cherish and nurture. A healthy river
will reflect a healthy community and will be a joy to all who use it.
Lourens River flood
alleviation measures study
The main objective of the Lourens River Flood Alleviation Measures Project was
to identify, and progressively implement, engineering measures to reduce the flood risk to
the towns of Somerset West and Strand. A secondary goal was to minimise the ecological
impact of the required river works and preferably improve the existing (rather poor)
condition of the middle and lower reaches of the Lourens River.
To this end,
the proposed engineering solutions for flood alleviation were evaluated in the light of
the following criteria:
*
physical structure of
the river canal (specifically with regard to flood alleviation);
*
ecological functioning
of the Lourens River and associated ecosystems;
*
recreation and other
social opportunities provided by the Lourens River and environs;
*
on-going maintenance
of the Lourens River and environs (specifically to minimise the need for extensive
maintenance).
The final
design of the river works was accomplished through an iterative process of evaluation and
adjustment of river cross-sections provided by the engineers. Ecologists examined each
cross-section along the length of the river in the field and outlined ecological concerns
and suggestions for softening the impacts at each river reach. The engineers responded to
the ecological recommendations by outlining constraints or acceptance of these, where
appropriate. Thereafter new cross-sections were produced and the heights of terraces on
the multi-stage channels were set according to ecological flow zones, which represent the
frequency of inundation and velocity of water extending from the centre of the river
outward up the banks.
Species
lists and planting densities for post-construction rehabilitation of the riparian
vegetation were supplied according to lateral vegetation zones based on the designated
“flow zone”. On the basis of this, the cost of rehabilitation of the vegetation,
using plants indigenous to the area, was integrated into the overall costs for the flood
alleviation river works.
Throughout,
the envisaged designs of the proposed river works were discussed with stakeholders,
primarily through a series of public meetings and house calls in areas directly affected
by the proposals.
The eventual
designs incorporated many of the suggestions proposed by the ecologists to soften the
blow, including:
*
multi-stage channels
where appropriate;
*
a policy of ‘non-disturbance’
of the river bed and lowflow channel form (including in-stream morphology, that is:
riffle-pool sequences);
*
uneven river margins;
*
establishing slopes of
at least 1:2, where possible;
*
revegetation with
indigenous riparian plant species;
*
major earthworks
focused on outside bends, thereby maintaining sinuosity;
*
establishment of a
nursery to propagate plants for the rehabilitation process;
*
establishment of a
2-year maintenance period for newly planted vegetation.
Not all of
the ecological recommendations could be incorporated, mainly because of space constraints
imposed by the urban setting of the river. For instance:
*
Gabions and retaining
walls were necessary where houses or other infrastructure (such as an electricity
substation) were situated close to the river.
*
The first phase of
construction had to start either at the bottom of the river or in an area that represented
a bottleneck during flooding. Although this is in contravention of ecological principles,
it could not be avoided because the municipality could not increase the flood risk in any
downstream areas by changing the carrying capacity of the river upstream of these. The
first phase of the project focussed on the section of the Lourens River between Sergeant
Street Bridge and the N2.
*
Requests from the
public led to the retention of some large alien trees, such as oaks and willows, where
they were not deemed to be a hindrance to the passage of flood waters.
In
conclusion, the project illustrated that it is possible to incorporate ecological
principles into major urban river works, even where engineering considerations must take
preference, to the benefit of the final product. The first phase of construction is almost
complete and revegetation has taken place. Because only indigenous plants were used, it
meant that only small plants were available and thus the recovery of the reach will take
several seasons. However, the combined engineering, town planning and ecological input,
including input from local residents, that went into the final design should ensure that
the final product is far better than would have been achieved without the comprehensive
multi-disciplinary approach.
The team
Client:
City of Cape Town: Helderberg District
Consultants:
Stewart Scott Consulting Engineers (Design)
Southern Waters Ecological Research and Consulting cc (River ecology)
University of Stellenbosch (River ecology)
IWR Environmental (River ecology)
Megan Anderson Landscape Architects (Landscaping)
Crowther Campbell and Associates (Public participation)
Sigma Beta (Design) |
