Exclusive interview with Steve Gillham, General Manager: Engineering & Scientific Services, Umgeni Water – he will address African Utility Week in May 2016 in Cape Town on “Assessing large scale seawater desalination as a regional water supply option”.
About Steve Gillham
Steve Gillham is a registered professional engineer, who has spent his entire working career in the water sector in South Africa. He was initially employed by the Department of Water Affairs and then moved to Umgeni Water where he has been for the past eighteen years. He currently holds the position of General Manager: Engineering & Scientific Services at Umgeni Water, responsible for the planning, design and implementation of the organisation’s infrastructure programme, as well as its water resource management, treatment processes, and water quality monitoring and analysis.
What is the current state of water availability in South Africa and who are our biggest consumers?
South Africa is a water scarce country defined by the low level of annual rainfall received compared to the global average, coupled with high variability of this rainfall and a high level of evaporation as a result of the hot climate. The country is classified as being water stressed where collectively the available resources are insufficient to meet the needs. Water availability varies spatial across the country, so some areas have sufficient resources at present whilst other areas do not. The current lack of surface water availability and limited further development potential will strain the country’s ability to fully support its growing economical requirements.
The agricultural sector is the largest consumer (approximately 60%) of water in South Africa, followed by the municipal/domestic sector at around 27%. Other large consumers of water are the industrial, power generation and mining sectors.
What is the link between access to clean water and the healthy functioning of the economy?
For economies to grow and prosper requires a productive and healthy population which is itself improving, growing and prospering. The lack of access to clean water has a direct impact on those in the population who are affected which in turn impacts on the economy. With unclean water sources often large distances from communities, many of the able bodied members of a community, especially woman, are forced to spend hours each day finding and transporting water. This water often contains water-borne diseases that cause health complications, which is usually further exacerbated by poor sanitation conditions and the inability to sanitise with water. Hence, it remains difficult for these communities to break out of the cycle of poverty.
Can you tell us more about the importance of access to clean water specifically? How does it compare to access to untreated water and are there uses for untreated water in an industrial context?
The importance of access to clean water for human consumption is discussed in the answer to question 3 above. As the availability of clean water in the natural water courses is diminishing as a result of interference and exploitation by human, the need to treat this water to a potable standard and then make it readily available becomes more critical.
There are many uses for untreated water, particularly in the agricultural sector for irrigation and stock watering. The water quality requirement for industrial purposes depends on the type of industrial process that it is used for and can range from untreated to a treatment level higher than that required for human consumption. In most instances, industrial water can be supplied at a quality slightly less than that required for human consumption. However, it is more practical to supply industry with the same potable water that is supplied to domestic users.
Who are our biggest polluters and what is being done to curb this?
Pollution of our water resources emanate from a large number of different sources, including agricultural, industrial, mining and municipal wastewater. The situation varies by region depending upon the predominant sector in that region or catchment.
The issues relating to resolving acid mine drainage are well known and are being tackled by both the private and public sectors. The Department of Water & Sanitation plays a regulatory and oversight role in monitoring, limiting and preventing pollution instances.
Catchment Management Agencies are in the processes of being established throughout the country with one of their roles being to safeguard the water quality within the country’s catchments. Municipalities also have a role to play with ensuring that industrial polluters are addressed and that their sewer systems and wastewater treatment plants are operated and maintained at an acceptable standard.
Tell us more about the importance of natural water catchment areas in the supply of clean water. How well are they being managed at the moment?
Catchments are the source of the water supply chain. The amount of runoff that is produced and the quality of this water are governed by how well a catchment is being managed. Here again, the quality of management varies tremendously across the country from excellent to very poor.
People often fail to recognise the link between healthy catchments and water supply and thus allow land use practices to occur which are counterproductive. The term Ecological infrastructure has been recently adopted to refer to naturally functioning ecosystems that deliver valuable services such as fresh water to people.
There are an increasing number of initiatives being launched to promote the safeguarding of our ecological infrastructure, particularly in key water supply catchments such as the uMngeni. A proposal has been submitted to include Ecological Infrastructure for Water Security as SIP 19.
Do catchment areas only channel water to residential areas or are they of importance to industrial South Africa too?
Catchments serve all water user sectors. Water that is abstracted from a river, dam or borehole for domestic and industrial use is usually first treated at a water treatment plant before being conveyed in bulk to a number of water use nodes where it is then reticulated to the numerous domestic and industrial users.
What are the most sought after skills in terms of water treatment and management at the moment?
Operators of water treatment plants are required to obtain certain registrations depending upon the size plant that they are operating to demonstrate their competence. There are still many treatment plants in the country that do not have the correctly qualified operators running their plants. Process technicians and engineers also play an important role in ensuring the efficient operation of a water treatment plant.
With the extent of water losses being experience throughout the country, there is a dire need to train plumbers at a reticulation/household level of expertise to assist in addressing this problem.
Water management at a strategic and regional scale requires a comprehensive and in-depth knowledge of how the water sector functions throughout the entire water cycle, whilst understanding its challenges and constraints. This type of knowledge cannot be gained through academic study alone and requires people that have been exposed to the sector for a number of years. Engineers with experience in regional water resource and supply infrastructure planning at a strategic and detailed level appear to be in short supply.
How can desalinising of our oceans assist in alleviating the strain on our water supply? Is it economically viable and is this a possible entry point for private sector investment?
Seawater desalination provides an alternate source of potable water to the conventional surface and groundwater options, with the major advantage that it is drought proof. There are a number of constraints to the widespread application of seawater desalination in South Africa, including: high energy requirements; and it only has application for consumers situated close to the coast.
At this point in time the cost to produce and supply desalinated seawater is far higher than the cost of supplying treated water from a conventional source. However, as technologies and efficiencies relating to desalination improve and thereby reduce the costs, whilst the cost of water from conventional sources continues to grow, there will be a point where desalination will become a competitive option to supply cities and towns situated along the coast. In some areas of the country, this point is not far off.
When the implementation of seawater desalination plants becomes an economically viable reality, private sector expertise will need to be brought in in one form or another. There are various institutional models which can be applied to the design, build, financing, ownership, operation, maintenance and hand-over components, structured in a variety of combinations. There are numerous examples of each throughout the world. Selecting the appropriate model will be based on each individual projects characteristics and who the project sponsors are.
What are some of the latest technologies being used in water treatment?
There has been a move towards utilising membrane technology as a filter media in more instances. South Africa lags the developed world in this regard. As the costs relating to this technology reduce, confidence and knowledge of the application increases, and the quality of the water requiring treatment deteriorates, there will be a greater momentum shift in this direction.
Conventional treatment methodologies are still effective. There is continual research and innovation in terms of finding ways to improve the efficiencies, reduce production costs and reduce the footprint size of these processes. The new technologies range from silt removal mechanisms throughout the process to disinfection.