Everyone has a landmark day or event that defines a breakthrough moment or turning point in their professional or personal lives. Interestingly, I have never learned the distinction between professional time and personal time; as though the transition between the two was triggered by the flick of a switch - when living becomes a resolute pursuit of purpose, then behaviour and time can only be personal.
Afrisam's new specialist road stabilisation product, Roadstab Cement, delivered outstanding results in tests conducted on the higher clay-containing soils found in the Free State - during stabilisation projects on the N8 in Tweespruit in the Free State, the N1 from Fonteintjie to Wurasoord, the N6 at Smithfield and the N5 from Bethlehem to Kestell.
I attended the SAICE Civil Talk on 25 June where the Gauteng e-tolling issue was discussed. I applaud the panel presenting well-balanced for-and-against arguments, as well as much needed history and context. Leaving the venue, it dawned on me just how divided opinion is.
General Hendrik Schoeman carved his place in history through the role he played in the First Anglo Boer War, but more so because of the controversy surrounding his actions during the Second Anglo Boer War. His violent death in May 1902, caused by the explosion of a lyddite bomb in an ashtray in his house in Pretoria, sparked speculation that his death was not an accident.
Since the late 1960s the Hartbeespoort Dam (HBPD) has become increasingly eutrophic. In the mid-1970s the dam reached a hypertrophic state due to severe algae growth in summer months. These blue-green algae blooms pose a high risk to human health, and have a detrimental impact on recreational activities and the socioeconomic potential in the area. Secondary to the algae blooms has been the prolonged growth of hyacinths in the dam and upper catchment over the last 30 years. Rapid urbanisation, associated with increased runoff, erosion, sedimentation and solid waste entering the dam annually is a growing threat. If this problem is not addressed appropriately, it will result in a further decline in the local tourism industry, as well as negatively impact economic growth and development in the North West Province with regard to agriculture, mining, industry, recreation and entire aquatic ecosystems.
The effect of eutrophication in the Hartbeespoort Dam manifests itself through vast and excessive algae blooms, as well as prolific growth of water hyacinths in all areas of the dam, although concentrations occur along the shoreline and in funnelled areas because of wind action. Furthermore, the seeds of the hyacinths also germinate from mid-July along the shallow areas. Calculated from the total incoming (external PO4 load >420 tons/annum) and available nutrients from the dam (internal PO4 load >2 000 tons), the growth potential of the photosynthesising biomass is much more than the estimated 10 000 to 20 000 tons of biomass which are produced over one year from the 2 000 hectare full-level surface area of the dam that is exposed to the sun. Variably the Microcystis blue-green algae and the exotic hyacinths (category 1 aquatic weed) make up most of the biomass. Biomass is managed by harvesting and removing both algae and hyacinths from the surface of the dam. This does not only curb the immediate growth, but also removes nutrients already trapped in the biomass. This approach results in an immediate improvement of the visible and noxious conditions in the dam.
The food web manipulation programme currently in operation in the Hartbeespoort Dam aims to improve the overall aquatic health of the dam by facilitating improved aquatic ecosystem diversity and services. An integrated biomonitoring protocol to manage aquatic ecosystems for impoundments became evident early in the programme and serves as a comprehensive pilot initiative which will guide similar future implementations in other dams.
This programme was developed to quantify the collective improvements in the Hartbeespoort Dam's ecological functioning after the implementation of the Harties metse a me remediation programme. Of particular interest, in this instance, is the ecological response to the food web restructuring initiative. The integrated monitoring programme consists of two components, namely (1) Biomonitoring (monitoring of biotic components) and (2) Integrated Water Quality Monitoring. Monitoring is conducted on a monthly basis at six representative localities in the Hartbeespoort Dam.
Development of criteria for habitat reconstruction and rehabilitation aims to deliver design criteria for habitat reconstruction and rehabilitation in the littoral and riparian zones for the following components:
Floating wetlands (littoral zone and in open water in quiet bays)
Lake bank vegetation (including terrestrial shrubs and trees) (riparian zone)
Placement of gravel and rubble beds (littoral zone)
Placement of additional structure in the littoral zone, such as large rocks.
Habitat reconstruction and rehabilitation in the context of the Hartbeespoort Dam refers to the placement and replacement of cover for aquatic biota. Cover in terms of rocks and plants, etc, will provide habitat for biota to feed from and to utilise as habitat and protection.
The Sediment Removal and Management Project deals with nutrient-rich sediments that contribute to severe eutrophication in the Hartbeespoort Dam (HBPD), as well as with sediments that should be retained and removed in future to protect the dam from sediment influx and associated build-up of nutrients.
In South Africa the Hartbeespoort Dam (HBPD) is among the water bodies most severely affected by eutrophication. It is positioned downstream of large industrial and densely populated commercial centres (i.e. the Johannesburg and Tshwane Metros) which discharge treated wastewater from sewage treatment works (STW) and urban stormwater.
At the onset of the Hartbeespoort Dam Remediation Programme, the need for a Communication and Knowledge Centre was identified as a vehicle to create awareness and provide information, as well as for capacity building and knowledge transfer. With this in mind, the Information and Communication Centre (ICC) first opened to the public in 2008 at the historic Tan' Malie se winkel. Late in 2010, the first Information Tent, situated at the dam wall, was upgraded to a 310 m2 structure and opened its doors as an extension to the Communication Centre.
The positive changes (more and longer periods of clear water experienced since 2009, absence of bad odour, etc) recorded within 18 months after the implementation of the Hartbeespoort Dam Integrated Biological Remediation Programme, are a clear indication of the powerful potential available within an integrated approach towards unlocking nature's ability to restore healthy ecosystems through biodiversity. This principle to conserve, protect and manage towards optimum biodiversity is not only a requirement in the National Environmental Management Act (Act 107 of 1998), but is echoed in the National Water Act (Act 73 of 1998) through the requirements of the Reserve to manage towards aquatic ecosystem diversity.
The age-old adage, where having to undertake an environmental assessment process in order to receive environmental approval for a development was considered a strain on the project, appears to have been diluted in recent years. In many instances, environmental management is now being seen by organisations as a valuable tool in ensuring that a development or operation is both environmentally sustainable and 'green' in nature.
The eThekwini Municipality is busy constructing a 1 200 tonnes/day Waste Transfer Station to serve the Durban area. This new waste management facility will provide a modern and mechanised means of transferring municipal general solid wastes to landfill sites efficiently and cost-effectively.
Jeffares & Green (engineering and environmental consultants) were appointed to design a modern, mechanised Waste Transfer Station (WTS) at Electron Road in Springfield Park, an industrial and commercial area north of Durban, near the banks of the Umgeni River.
A guideline document and software system for the measurement of carbon emissions by all operations associated with the manufacture and application of bituminous products in South Africa's roads industry is now available for implementation.