To all SAICE members who support the cause of civil engineering through volunteerism, and who faithfully pay their subscriptions - thank you for your commitment to the Institution. The profession is moving forward because of your contribution.
Africa has seen a number of revolutions in the period between 2000 and 2013, such as the Libyan, Tunisian, Sudanese and many others. The latest that still rings bells in most of our minds is the Egyptian revolution that ushered in the government of President Mohammed Morsi on 30 June 2011.
Johannesburg Water, a leading South African water and sanitation utility, has over the last few years embarked on a multibillion-rand capital investment programme to upgrade, expand and modernise each of its six wastewater treatment facilities. The upgrading of the sludge digestion facilities forms an integral part of this programme.
As we try to understand the challenges that face us we should always try to learn from the experience of others - especially from their mistakes, but also from their successes. I am fortunate to be involved in a review of water policy in the Netherlands, which has given me some new perspectives about the challenges of water management in South Africa.
South Africa faces the challenge of operating and maintaining world class-infrastructure, while at the same time experiencing a backlog in services for those living in informal settlements. On-going planning for future growth and development must be performed to ensure acceptable future service levels. As existing infrastructure ages and deteriorates, maintenance and the prioritisation of infrastructure refurbishment become critical. Planning for the future includes planning for infrastructure provision, planning for maintenance and pipe replacements, as well as sound financial planning. Water and sewer master planning has traditionally taken the form of establishing a model of existing infrastructure, followed by compiling the master plan defining future improvements to the system to meet the requirements for expected developments. Infrastructure refurbishment programmes and proactive component replacement actions should be designed to be integrated with the master planning process. With the extensive GIS-based information from the Wadiso and Sewsan data models available as part of the master planning process, GLS has implemented a pipe replacement prioritisation methodology specifically suited for South African conditions, also taking account of the available information and reliability thereof.
The South African Plastic Pipe Manufacturers Association (SAPPMA) warns that the replacement of old water pipes around the country is long overdue. According to Jan Venter, SAPPMA chairman, the existing steel and asbestos cement pipe infrastructure in South Africa has undoubtedly corroded during the last 50 years.
Reducing the operating costs of water infrastructure projects demands improved efficiencies in operating treatment plants (water and wastewater). To eliminate or reduce contaminants in raw water in order to render it safe for drinking, or to reduce pollutants in wastewater to render it acceptable for disposal into our environment, costs money. These operating costs include the following:
Wastewater discharge fee/Water resource fee
Maintenance and replacement cost
Sludge disposal cost
Operating costs need to be recorded and analysed in the course of operating and maintaining the plant, thereby allowing Management to identify areas for conservation and to determine where costs are being expended inefficiently so that appropriate measures can be taken to reduce costs.
The eThekwini municipality is throwing Durban two urgently needed water lifelines - the second phase of the Western Aqueduct (WA) which begins at Inchanga Station and ends at Ntuzuma with spur pipelines to Mount Moriah and Tshelimnyama, and the urgently needed Northern Aqueduct Augmentation (NAA) project, which will carry much needed water to the eastern and northern regions of eThekwini as far as Umhlanga, Phoenix and Waterloo.
Neil Macleod, head of eThekwini Water and Sanitation (EWS), has confirmed that the two long-term projects, which are expected to span at least seven years, are now officially under way, although at different stages of roll-out.
He says the initial studies carried out by EWS indicated that the optimal solution to address imminent capacity problems would be the installation of a new bulk supply pipeline from Umlaas Road through the outer and inner west areas, and terminating in Ntuzuma.
This became known as the Western Aqueduct.
What constitutes a wetland is often not fully understood. Common misconceptions are that wetlands must be wet, have a river running through them, or are always situated in low-lying areas. The definition of a wetland is much broader and more textured: they are characterised more by soil properties and flora than by an abundance of water. Wetlands can be seasonal, staying dry for up to several years, or they can be permanently wet. A pan, for example, is a wetland which forms in a depression. This may even occur at the top of a hill, nowhere near a river, and dry out completely during the dry season. Wetlands also come in many sizes - they can be as small as a few square metres (e.g. at a low point along the side of a road) or cover a significant portion of a country (e.g. the Okavango Delta).
Construction of a new bitumen-surfaced road or airport pavement in an arid area usually requires the use of several thousand cubic metres of water per day for compaction.
The use of salt water - or even only brack water - for compaction in the past has had mixed success and often resulted in surface disintegration of the primed base course and/or blistering of the surfacing. This experience led to fresh water usually being specified - particularly in the granular base course - in order to avoid such salt damage.
The Nacala Dam, located on the Muecula River approximately 30 km southwest of the city of Nacala, in the Nampula Province of Mozambique, was designed and constructed between 1968 and 1975 to serve as the main water source to the city and port of Nacala. However, the lack of capacity of the original spillway gates caused the dam to overtop twice in its history. Due to the risk of dam failure, water levels at the dam were therefore kept low, reducing the water supply to Nacala significantly.
WITH RCC (roller compacted concrete) placement ongoing at the 1.6 million m3, 173 m high Ayvali Dam, and construction recently started at the 70 m high Kotanli Dam, both in northeastern Turkey, ARQ's dam activities for 2013 will also encompass a number of smaller dams, including the 23 m high Umti and the 18 m high Wadi Kalboh dams in Oman, the 30 m high Mndwaka and the 24 m high Port St Johns dams in South Africa, the 24 m high Mukurumudzi Dam in Kenya and the 16 m high Arnaud Dam in Mauritius. In addition, ARQ is assisting with repair works and a new spillway at the 20 m high "My Own Dam" in Mpumalanga.
The availability of adequate water of acceptable quality is essential for South Africa's social and economic development. South Africa has an arid climate and consequently the storage of water is essential, in both dams and groundwater aquifers. The importance of water infrastructure, including its development, maintenance and rehabilitation, is accorded a high priority, as reflected in recent Parliamentary discussions and in the National Development Plan. SANCOLD is one of the key role-players in the water sector and over the years has made important inputs.
The popular Aqualibrium Schools Water Competition has come a long way since its introduction ten years ago. SAICE and Rand Water celebrated their centenaries in 2003, and decided that a new school outreach initiative with water as theme should be developed to form part of these celebrations. A search for ideas was started, culminating in the Aqualibrium competition concept when a group of third-year civil engineering students at the University of Johannesburg came up with the concept as part of a class challenge put to them by Prof Kobus van Zyl.
Tara Schwulst, at the time a pupil from Stirling Primary School in the Eastern Cape, has received a number of awards for an interactive educational water game that she developed in 2012, named Every Drop Counts. Tara's board game is not just about having fun, but teaches players of the game important facts about water - our most precious resource.
For the past two decades SRK Consulting partner Murray Sim has watched millions of rand being spent on controlling pollution in South African cities and towns. Now, he says, we need to stop wasting money.
The decision to invest in good quality water meters that are specifically designed and optimised for South African water conditions, can significantly reduce non-revenue water and enhance and maximise an authority's revenue.
Engineers, operators and owners face many problems in the maintenance and refurbishment of pipe joints. Barry van Jaarsveld, Regional Manager of Victaulic, discusses the types of joining solutions commonly offered in the market, their advantages and disadvantages, and explains how the right choice of pipe joining method can significantly cut operating costs.