Irrigation system to save 80% water

Bart Rehbein at the pilot plot on Yas Island where a new irrigation system is being tried out with Aldar.

Dubai: An irrigation system of gravel and pipes that run 60cm below the surface of the ground is showing positive results for growing lush grass with just 2.5 litres of water per square metre — compared to the usual requirement of ten to 12 litres.

At a pilot plot on Yas Island, even more water savings have been recorded when growing indigenous drought-tolerant shrubs such as halophytes.

The plot, loaned by Aldar, is the testing ground for seeing how little water can be used to grow various plants, from grass to bougainvillea to salt-water tolerant shrubs, that are widely used to green residential areas as well as the island itself.

The technology developed by Epic Green Solutions starts underground. Before anything is planted a plot is excavated and lined with a waterproof tarpaulin. Layers of gravel and dirt follow placed around a "passive integrated chamber", or a large half pipe. The pipe is mined with holes in strategic places to allow water to flow through but soil and sand to stay out.

The chamber which runs the length of the desired plot is connected to a water reservoir filled with treated sewage effluent for irrigation.

It can double up as a water catchment tank in rare but heavy seasonal rains. The waterproof tarpaulin collects water — instead of it being lost below ground — and sends it back to the water reservoir.

"It's all about gravity," said Bart Rehbein, managing director, Epic Green Solutions, which devised the system in the US where it is used to irrigate football fields. "Evaporation is the biggest problem in the region. This system saves about 80 per cent of water traditionally used with drip surface irrigation. The chamber disperses water underground straight to the plant roots."

"We are trying to show that you can do typical landscaping and do it with 80 per cent less water," said Rehbein.

The project has been two years in the making said Geoff Turnbull, landscape architect at Aldar Properties.

Source: http://gulfnews.com