A 360,000 litre underground rainwater harvesting tank from Ausdrain was recently installed at the newly constructed Salvation Army care facility in Chapel Hill, Queensland.
The tank had originally been designed as two pre-cast concrete tanks, but as site access was difficult an alternative system was required. As the tanks were located at the rear of the building the only access to crane large concrete tanks in was from street level located above a high bank obstructed by trees and vegetation.
The Ausdrain rainwater harvesting system was considered as the most practical alternative for this project, and was also cost effective.
The rainwater harvesting tank measures from Ausdrain measures 11.4m x 18.0m x 1.35m and consists of 4388 Ausdrain EnviroModules. The outside of the rainwater harvesting tank is surrounded by a 1mm re-enforced polypropylene liner and there are 2 precast pits at either end of the tank that measure 900mm x 900mm each. The first pit is connected to a 375mm inlet pipe and has a removable maximesh screen over the inlet to the water storage tank. The second pit houses a submersible pump that connects to a 50mm suction line and a 375mm overflow pipe connects to the street stormwater drainage.
The EnviroModules were delivered to site in flat pack form and a fork lift was used to move them to the rear of the building.
The modules were then assembled in close proximity to the excavated pit. The rainwater harvesting tank was constructed in just 3 days with all components of the tank installed by hand, avoiding the need for costly crane equipment.