Water treatment plant

Nebo Road Water Treatment Plant

The Nebo Road Water Treatment Plant is located approximately 3 km to the south-west of the Mackay CBD on land adjoining the Lagoons Reserve, which is part of the Mackay Botanical Gardens.  It currently provides water to a connected population of around 72000 people. 

Raw water is sourced from the Dumbleton Weir on the Pioneer River or from groundwater bores located in close proximity to the WTP.  Approximately 90% of the water is sourced from the weir, which is controlled by Sunwater, with the remaining 10% sourced from the bores, controlled by Mackay Water.

Raw water from Dumbleton Weir is pumped from the pumping station to the WTP where it is firstly dosed with liquid Alum and undergoes primary settling in one of two clarifiers.  The water from the clarifier is then dosed with a polyelectrolyte in the delay tanks before being filtered in one of the twelve river water sand filters.  The filtered water is stored in the filtered water tank where it is dosed with chlorine before entering one of three balance tanks.  Water from the balance tanks is distributed within the Mackay water reticulation system via the high lift pumping station.

Raw water from the bores is pumped to the WTP where is dosed with chlorine, aerated and dosed with potassium permanganate and lime to oxidise and manganese.  A polyelectrolyte is added in the delay tanks before the water is filtered in one of the four bore water sand filters.  The filtered sand is stored in the filtered water tank where it is dosed with chlorine before entering the balance tanks.

Backwash water and sludge from the clarifier and sand filters is pumped to one of the four earthen sludge lagoons located to the west of the treatment plant in the Lagoons Reserve.  The resulting supernatant is discharged to the lagoons while the sludge dries naturally.  This discharge is a licensed discharge under Integrated Authority No. NM0250 (C1).  A contractor transports the dried sludge from the lagoons to Mackay Regional Council’s solid waste disposal facility at Bayersville.