The basin (middle) surrounded by ridgelines (foreground and rear) will be flooded with water from the Adelaide River during the wet season, and used to augment Darwin’s water supply. Photo: NT Government.
An ambitious project to increase water storage and supply for Darwin has taken a big step forward after the awarding of a $6 million contract to NT-based company SMEC Australia to deliver the final concept.
The Adelaide River Off-Stream Water Storage project (AROWS) will see a depression in the landscape adjacent to the Adelaide River used to hold and store water, without the need to dam the river itself.
AROWS is part of the Darwin Region Water Supply Program, which also includes the Manton Dam Return to Service.
The Menton Dam was built on a tributary of the Adelaide River in 1942 and was superseded by the larger Darwin River Dam in 1972. But with Darwin’s growth, the Darwin River Dam’s capacity now needs to be augmented, so the Menton Dam will be upgraded and recommissioned.
A Territory Government release says the AROWS project will secure Greater Darwin’s water supply for the next 50 years, and will be a critical enabler for agricultural and industrial growth. It says AROWS will provide a long-term water supply for the Lambells Lagoon Agribusiness and Middle Arm Sustainable Development precincts.
The AROWS site is located north of Lake Bennett and east of Menton Dam and will take advantage of a naturally occurring basin inside a ridge formation that can hold water next to the Adelaide River.
Two containment barriers will be constructed at low points of the basin so that water can be stored, and the Adelaide River will supply AROWS with water via a controlled pump system during the Territory’s wet season. Water will then be stored in the AROWS basin, and can be pumped via a new pipeline to the proposed Strauss Water Treatment Plant for distribution.
An information page says current modelling shows AROWS can hold around 250 gigalitres (GL) of water at full supply level, and will supply 60.2 GL per year to the Darwin region. By comparison, Darwin River Dam holds 303 GL of water at full supply level, but can only supply 32 GL per year.
The design is expected to be completed by mid-2025, with construction starting in 2026.
A satellite pic and graphic of the location of the AROWS basin relative to the Adelaide River, Menton Dam and Darwin River Dam. Image: NT Government.
Minister for Territory Development Eva Lawler said the AROWS project is one-of-a-kind.
“No other state or territory is securing long-term water supply through infrastructure with this degree of innovation and sustainability,” she said.
“Water is a key enabler for urban, economic and agricultural growth, and this investment will play a large role in reaching our goal of becoming a $40 billion economy by 2030.”
“It is very exciting to have SMEC Australia on board, a highly skilled company that has been operating in the Territory for over a decade.”
SMEC Australia Area Manager Jocelyn Ellero added, “AROWS will become an iconic project in the NT. I am not only looking forward to delivering a project of such high technical calibre, but the impact we will have on the community and future growth of Greater Darwin.”
