Water reduction project takes off
London Stansted Airport has carried out a programme of leak detection and pipe repair that has reduced water consumption on the site by nearly a third and water use in 2011 fell by 205m litres compared with the year before. Sustainable Business finds out more.
Dr Andy Jefferson, Stansted's head of planning and sustainability, says the project was funded out of an ongoing operational budget of £500,000 per year for management of the 957-hectare airport site, with the cost around £100,000.
Jefferson says: "We're delighted to have achieved such a significant reduction in water use, thanks largely to the work we've undertaken to identify and repair failures in our very extensive pipe network.
"Recently announced restrictions on water use in the region are a timely reminder it's never been more important to conserve scarce resources, stop avoidable waste and limit energy use. We are very aware the airport sits within one of the driest areas of the UK, so it's vital we do all we can to help reduce water consumption and protect availability.
"Working with the Environment Agency and Veolia Central and with the help of specialist contractor Aquatech Engineering, we have committed over £500,000 this year alone to continue monitoring, maintaining and improving our water network at the airport.
"Additionally, last year's investment to reduce water leaks will in turn drive operational cost savings and reductions in energy use due to the lower volumes of water pumped around the site."
Stansted's overall water system is managed in three segments - surface water, sewage and the pipework system, which runs to some ten miles of pipe, ranging in diameter from 30cm to around 2cm.
"The water infrastructure ranges in age going back to World War II for some for some of the earliest areas of the distribution system, with just over half of the site's water pipe network going back that far."
The £500,000 budget for maintenance and upgrades is a permanent fixture, according to Jefferson. He explains that the investment goes towards managing all of the water infrastructure, operation, maintenance and all the performance monitoring and adds that it is very much an ongoing commitment to manage all the aspects of the water systems - some ten miles in total.
The site was divided into three zones, and leakage surveying work was carried out by Aquatech Engineering using an acoustic technology in each of the three areas, in order to pinpoint leak locations.
Jefferson says: "The contractor used specialised survey equipment that works using sound - essentially utilising microphones on key nodes in the water distribution system. The pipes are underground of course, so this helped us detect areas of leakage that would otherwise not be visible. The instrument is able to listen for noise produced as water bleeds through a leak and is sensitive to within a couple of metres."
The accuracy of the instrumentation allowed the project team to minimise the amount of excavation necessary in order to reach and repair leaks, and helped them avoid nearby structures and other buried services.
While Jefferson says the financial savings on Stansted's water bill have been significant - particularly when associated reductions in energy use are considered too - it is the environmental outcome that is perhaps more important.
He says: "We've managed to save 205 million litres of water as a result of this work - about 33% of the water brought into the airport site. It's a tremendous achievement for us, and we're very pleased with the figure.
"We're very active in the management of surface water for instance, which is a key area of activity for us. We have spent in excess of £1m to improve performance. And the leak detection and repair project cost over £100,000, and while there is a significant amount of financial savings - on top of reduced water costs there is an associated energy saving through not needing to operate pumps, pumping systems and pumping plants to move water around the airport site. "But it's all part of reducing our impact on the environment."
While Jefferson's expertise is in the arena of water management, he says the airport has a number of other areas where there are opportunities for cost savings and reduced environmental impacts - for example in energy management and the reduction of carbon emissions.
He says: "We have a utilities and environment team whose current aim is to look at these other areas and how we can achieve improvements in performance. We look very carefully at where we can get the best return on investment and maximise the benefits to our performance and the environment."
And the Stansted team hopes further action can be taken on water management. Jefferson says: "This project was funded by operational rather than capital spend, and our approach is that we're reviewing and improving the whole process by which we manage all parts of our water system through our water strategy.
"We know there is still more we can do, that is why we are currently reviewing our water strategy in advance of publishing a five year plan later in 2012 as part of our overall drive to deliver the sustainable and responsible growth of air travel at the airport. I'm confident this project's success will help drive further initiatives to identify and deliver further water use reductions by both passengers and airport staff."
"So we're looking at all the different components of our water systems, the available sources of funding, and as well as commercial performance how we achieve compliance with the various legislation on water."