Roger van Gelder, an independent water conservation consultant, has done some investigation on no-water urinals at the University of Washington (N.W. USA) and found that a ‘sludge’ builds up in both the horizontal and vertical legs of the drain pipe behind the urinal.

At the time of printing the sludge had yet to be analyzed to determine exactly what it contains but van Gelder believed it to contain hair, proprietary fluid from the trap, bacterial growth, urine crystals, etc.

Industry experts John Koeller and Bill Gauley witnessed the research and reported that apart from the sludge being “pretty disgusting!”, the drain pipes were between 1/3 and 2/3 blocked after six months (new drain pipes were originally installed).”

Clark says the industry, in conjunction with the NPRF technical advisory committee, has been conducting long-term trials in the performance of waterless urinals.

“Without water flushing the drain, the discharge pipe waste line will eventually block up. So we need to review the Standards to address the need for better overall design consideration. This could mean running fixtures past the urinal first, instead of having them on dead legs or dead branches.”

Some of the long-term effects of problem drains are being experienced, with home-owners calling plumbers out to rectify drainage system blockages that cause odors inside buildings.

Plumbing regulators are dedicated to conserving water. However, Clark and other regulators also want to ensure that plumbing systems are not causing blockages that can lead to overflows and adversely affect public health and the environment.

Trials are taking place in Perth, Western Australia, and Canberra, the national capital. The continuation of such trials is essential to the overall outcome of the project.

Caroma, Australia’s main supplier of plumbing fixtures, “fully supports the project because it believes that fixtures should be fully compatible with the drain line i.e. fully matched in performance.”

The technical advisory committee aims to have all trials completed in the next 18 months.

Caroma’s research and design manager Dr Steve Cummings has been researching other overseas models to compare overseas practices with Australian practices. He found that other countries were facing similar problems.

Germany in particular has reduced its flow rates and water consumption to almost half the level of a typical Australian dwelling.

There is concern among the general community in the United Kingdom regarding government water containment initiatives.

Waterwise UK head of research Joanne Zygmunt says sewers in many places have to be flushed with substantial amounts of water because flows from dwellings are insufficient.

“The average per capita consumption of water in the UK is about 150L (40 gallons) a day. If this goes down to as low as 100L (26 gallons), problems may be experienced. The government vision for new homes is about 110L (29 gallons) per person per day.”

Question: are the sewers in the UK typically combined (i.e. is the same sewer used for sanitary as well as storm water)? Based on the following few sentences, should you say, “In the past the UK could rely on the generally dependable rainfall to allay any such concerns.”

However, Waterwise director Jacob Tomkins concedes that water scarcity is a real concern.

“In reality the UK has less available water per person than most other European countries, and the Thames Valley is technically classified as semi-arid,” he says.

“Climate change is making this worse as rainfall becomes less regular and more intense, leading to floods and droughts.