The Valetta Irrigation Scheme – now part of the MHV Ltd Scheme after an amalgamation with neighbouring Mayfield Hinds Scheme. This was the first major scheme for Aquaduct NZ Ltd. Together with sister company Bosch Irrigation, Aquaduct took on the design, supply and construction for the project. This included 84 km of large bore PE pipe of which 16km is massive 1600mm diameter.
The Valetta Irrigation Scheme is supplied by the open channel from the Rangitata Diversion Race (RDR) to the Valetta district irrigation area of 13,000 hectares at a flow rate of up to 4.5 cumecs.
The pipe system replaced an open race system. This resulted in significant savings by recouping the evaporation and seepage loss of channeled water and allowed 37% percent more area to be irrigated using the same amount of water. It also saved on-farm pumping costs and provides the possibility of electricity generation.
In total Aquaduct supplied pipe to the project in sizes from 1.6 metres diameter down to 200mm. 5,800 tonnes of polyethylene material were used to complete this project which was mostly supplied in pipe lengths of between 100 and 250 metres.