Al Sammaleah Island

A 2007 demonstration on Al Sammaleah Island, Abu Dhabi, with two aims. The first was to measure how much water a conventional landscape uses compared with a sub-surface system. The second was to run EPIC on water nobody else wants: Gulf seawater, air-conditioning condensate and unfiltered grey water.

Two plots of Bermuda grass made up the water-saving comparison: Plot 1 on EPIC, 126 m², and Plot 2 on traditional pop-up spray sprinklers, 138.75 m². Both were metered from 1 August to 9 September 2007. Plot 1 averaged 0.686 US gallons per m² per day and Plot 2 averaged 3.250, which is 2.60 and 12.30 litres. Measured per square metre, that is a saving of 78.91%.

The seawater plot was planted with Sesuvium portulacastrum and irrigated straight from the Arabian Gulf, where salt runs from 45,000 ppm to over 50,000 ppm. It was built like any other EPIC system with one addition: a drain line back to the Gulf to stop salt building up in the soil. After a short hardening period the Sesuvium grew well. Its pump ran on a small solar panel, where a high-pressure system would need a far larger solar supply.

Two more small plots tested other water sources. One ran on air-conditioning condensate and the other on grey water from an office building. The EPIC System does not clog, so the grey water went straight into the system with no pre-filtering. On an island, power for a pressurised irrigation system cannot be taken for granted.