A market review
May 11th 2009

Mike Norton , chairman of the UK Rainwater Harvesting Association looks at the market development of this technology and the impact that it can have

Thanks to the introduction of piped mains water directly into our homes, Victorians soon dispensed with harvesting rainwater from the roofs of their buildings. And yet, here I am sitting in my office at Kingspan, 100 years on, happily reflecting on the huge growth in rainwater harvesting in the UK over the last couple of years.

What goes around…as they say. The concept of capturing rainwater for non-potable uses is now firmly back on the agenda, and is expected to become a major part of new-build projects in the UK going forward – credit crunch permitting. Indeed, sales of rainwater harvesting systems have gone up by 300 per cent in the last two years alone and are continuing to rise. There are a number of drivers that, over the last 12-18 months or so, have been pushing the use of this cost-effective and simple technology.

Legislation

Conservation of water stocks has now become a priority for architects, builders and developers to achieve an excellence rating against criteria set by BREEAM and The Code for Sustainable Homes. To achieve ratings at the higher end of the Code, developers have to install more water-friendly appliances and rainwater harvesting, to reduce water consumption in the property from an average of 160 litres per person per day, to as little as 80 litres.

Code level 3 became mandatory mid-2007 for the public sector and will be mandatory in 2010 for the private sector. The higher levels are phasing in over the next few years. However, many developers are already achieving level 3/4 and a number are aiming for level 6. Developers can achieve level 6 with rainwater harvesting alone, but only if the roof area allows sufficient collection; for some eco-town/small homes there is a need to supplement this simple technology. Twelve months ago, there was little else on the market to help reduce domestic water consumption down to the amount required for a level 6 rating. However, I believe this changed in 2008 with the launch of a new viable, affordable “greywater recycling”filter, which I’ll talk about in the next section.

But it’s not all about saving water: rainwater harvesting also has a part to play in flood prevention. This time last year, much of the talk in the industry and government was around removing the threat of flooding following the devastating events of that summer. Although the weather was less inclement this year, flooding remains an ever-present, unwelcome side-effect of global warming.

The new planning policy statement PPS25, which came into force in 2008, now requires planning authorities to undertake strategic flood risk assessments as part of their development planning. Rainwater recycling systems reduce surface run-off during heavy rainfall and pass the recycled water indirectly via reuse applications to the foul system rather than the storm drains, so that it poses slightly reduced flood risk.

Greywater recycling

Unfortunately, as I’ve already alluded, there is often a limit to the amount of water that can be collected through rainwater harvesting. Modern high density housing means the average roof area is around 90m2, which represents a significant restraining factor on the capacity of the system. Although it wouldn’t be beyond the wit of man to harvest water from other hard surface areas (patios and driveways, say), there are understandable concerns about contaminants in the water gathered from these two sources.

We need to support rainwater harvesting from roofs with additional supplies if we are to achieve the levels required by the Code, and for this we need to consider water reuse or “greywater recycling systems” that filter and collect bath and shower water for loo flushing and garden irrigation.

A big step forward for water conservation in 2008, in my opinion, was the launch of a small, effective greywater filter aimed at the domestic market, called Ezy-Filter. This little gadget, about the size of a champagne bottle, connects to a dedicated downpipe on an outside wall. Ittreats soap, detergents and other impurities from bath, shower or basin water giving clear water.

The water can then be stored in a water butt, or passed into a rainwater harvesting tank, and used on flower beds, for flushing loos, or for washing clothes and vehicles – in fact a range of tasks, with the exception, of course, of drinking. Used with rainwater harvesting, greywater recycling can double the water savings for an average household, reducing the per capita usage of mains water down to just 80 litres, on average - the target for code level 6.

The next 12 months

There is no doubt that the market has taken a hit in the domestic housing sector thanks to the credit crunch. However, there remain opportunities in both the commercial and public sector applications. Growth depends on a number of factors, and the two I want to focus on here are education and consumer confidence.

Education

In my view, there is still a great deal that needs to be done around educating developers, the construction industry, and the public at large, about the requirement for rainwater harvesting and greywater recycling systems. I would like to see far greater awareness generally about how wasteful we are in our uses of drinking quality water. Consider that the average person is allocated around 200 litres per day by the water companies. We actually only drink around one/two of those litres,per day (or just 1% of that daily allocation). The remainder is used in washing machines (40 litres), dishwashers (40 litres), baths (120 litres) and up to 40% of the water we use during the summer may simply be poured on the garden.

None of this water needs to be drinking quality and to continue to treat it as such is, I believe, a huge waste of valuable energy and resources. Rainwater harvesting and greywater recycling systems, however, provide good quality non-potable water, without great investment.

Standards/consumer confidence

As more and more systems come onto the market, there is a pressing need to instil early consumer confidence in the sector, both around the technology and the quality of the resulting water. Achieving this requires the application of British Standards, and I have devoted considerable time over the last 12 months to contributing to writing one for rainwater harvesting.The result, BS8515 for Rainwater Harvesting, is due for publication in January.

Its aim is to ensure comfort to specifiers and consumers, and compliance by suppliers, to minimum standards. It also addresses any concerns about the possibility of cross-contamination of mains drinking water with rainwater. Concerns about the size of greywater filtration plants and the quality and purity of greywater captured from such systems must also be alleviated – the new British Standard BS8525 for Greywater will be introduced later in 2009.

I am also calling for a national training programme that will ensure standards of installation are meeting minimum criteria. It is disturbing to me that anecdotal evidence suggests many of the complaints that suppliers are fielding are not down to issues with design, but, instead, poor or incomplete installation. That represents a major cost to the industry in terms of warranty payments, and needs to be addressed – the last thing we want is for a few ‘cowboys’ to undermine trust in the sector before it is fully established. If we achieve all this, it’s my belief that in four years time, perhaps 75% of new builds could have some form of water reuse system installed. I’ll drink to that!

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