Dealing with water and sewerage may not be sexy, but the past few decades have seen considerable evolution with regard to hydraulic engineering in buildings and building services as challenges have opened up in areas such as environmentally sustainable engineering, black water mining, grey water recycling, and blue roof storage attenuation.
With this in mind, it is timely to pause and consider some of the ways in which the sector might change going forward and where some of the opportunities may lie.
First, building codes and standards are likely to have to change in order to adapt to advances in technology and changes in types of buildings under construction. As the volume of high rise construction grows, for example, issues emerge with regard to fluctuation of air pressures and resulting cross-contamination in terms of high rise drainage stacks. In Dubai, for example – which has more than 73 completed buildings now standing at over 200 metres in height – GHD senior hydraulic engineer Les Wilson says current building codes do not adequately address these issues.
Locally, the AS3500 standard used by engineers to estimate pipe design flows to determine necessary pipe size and upon which water utilities base estimates for water demand and use has hardly kept up with modern times. It was first introduced in 1979 and last revised in 2003, Victoria University senior engineer in water engineering Dr Anne Ng says. This means it does not account for recent improvements such as such as half flush toilets and efficient fixtures and fittings. Thus, it leads to a considerable degree of overstatement of requirements. There is also no current Australian standard covering the installation of rainwater harvesting systems and tanks despite their growing prevalence.
Going forward, standards in areas like this will have to change in order to reflect the reality of modern buildings and building systems.
Australia will also be impacted by much of the current research being done on plumbing and drainage overseas, Wilson says. In the United Kingdom, for example, researchers at the Heriot Watt University has made strides into the study of pressure surge analysis in large scale engineering fluid flow systems and have developed a modelling and simulation tool. Dr Michael Gormley from the school has developed a PAPA (positive air pressure attenuation) fixture which, when matched with appropriately placed AAVs, has allowed sealed systems to outperform traditional naturally aspirated drainage stacks, he says. Countries such as Japan, Hong Kong and Taipei are refining plumbing systems, while in Brazil, research being done on real time water usage data could well reshape water loading units around the world.
Another interesting area is maintenance and the avoidance of contamination in pipework. In Hong Kong, at least 1,500 local households were impacted in July by a drinking water scandal which saw the discovery of lead at levels three times those of World Health Organisation recommendations. Back home in Australia, a study in April found that lead levels in water pipes which service as many as 26 towns in the north-east of Tasmania exceeded national guidelines by up to 22 times. Going forward, Ng says greater consideration will be needed as to how pipes are going to be maintained and cleaned and how biofilm will be handled.
“In civil engineering, we look at the bigger scale like stormwater pipes and pipes which are deteriorating and getting very old,” Ng said. “Now the same goes for the water supply system in the hydraulics for buildings, where they will deteriorate and not only leak but have all this biofilm material that has been building up for years.”
“I think it’s (the key to avoiding contamination) mainly in the maintenance side of things. You design and you install something, but you’ve got to look into the long-term maintenance of these things. Nobody is talking about how we actually clean the pipes. With the ducted heating and air-conditioning, you see all these ads about having to clean them every year, but you don’t really hear about the water supply pipes.”
Last, there is a looming shortage of skilled professionals in this area, a phenomenon Wilson says is being exacerbated by the lack of appeal with regard to water and sewerage as an area of engineering along with the aging of the skilled construction workforce generally.
He says in places like Europe, a movement throughout the 1990s to prioritise academic over technical skills as the preferred route to follow in engineering led to an oversupply of graduates who were computer literate but who lacked sufficient technical expertise with regard to engineering and hydraulics to be of any practical value in the workplace.
Ng, meanwhile, talks of a skill vacuum in terms of pipe design. She says many of those now designing the system for building blocks come from trade backgrounds such as plumbing. While these people bring valuable hands-on experience to the role, she says there is a shortage of those who can look throughout at the design requirements for delivering better pipe works services.
One concern revolves around the lack of emphasis in terms of hydraulics as a field of engineering within much of the university environment. Wilson would like to see the introduction of a degree course on the back of a hydraulic diploma, similar to one offered by the University of Greenwich in London. He says there is considerable demand for hydraulic and public health engineering and a variety of opportunities for those who wish to pursue careers within that field.
The environment within hydraulic engineering is changing. For those who embrace this, interesting opportunities lie ahead.