Newcastle Fresh Water Supply
The Newcastle fresh water supply is made up of a range of water sources located within the Hunter/ Newcastle area including dams and sandbeds. The key components of the Newcastle water supply includes dams such as the Chichester and Grahamstown Dams. Water drawn from sandbeds at Tomago and Anna Bay also form part of the Newcastle fresh water supply.
High standards of health and the provision of suitable conveniences for modern life in Newcastle and the Greater Newcastle area demands an adequate supply of wholesome water.
Newcastle has a reasonable annual rainfall as a source of water, but as in all areas, a proportion of this supply is lost due to a number of factors.
Rainwater loss in Newcastle
- Evaporation causes the loss of some free flowing rainfall due to Newcastle’s relatively warm climate.
- The abundant vegetation present throughout the Greater Newcastle catchment area also causes loss of rainfall.
- Run-off over water over the ground is another source of loss of rainwater.
- Absorption in areas which readily absorb water causes some rainwater loss until it reaches ground water.
Dams and Catchment areas- Newcastle Water Supply
Water supply in Newcastle includes the following major sources of fresh water.
Newcastle Water Supply : Dams
Grahamstown Dam. Constructed between 1955 and 1965 this dam is the largest drinking water supply dam in the Hunter/ Newcastle area. The dam is an off-river storage facility collecting water from the Williams River and also rainwater from its own catchment.
There are key components to the Grahamstown Dam supply scheme.
- Seaham Weir, which limits the upstream movement of tidal saltwater
- Balickera Canal and pumping station which transfers water from the Williams River to Grahamstown Dam.
- Campvale Pumping Station.
- George Schroder Pumping Station and delivery mains deliver water from the dam to the water treatment plant.
- Grahamstown Water Treatment Plant.
Chichester Dam. Constructed 1917-1926. Currently the Chichester Dam contributes about 35% of the Newcastle/ Hunter area’s potable water supply. This dam is one of Newcastle’s key freshwater supply facilities. The dam wall is 254m long and 43m high.
Newcastle Fresh Water Supply : Sandbeds
Tomago Sandbeds. The Tomago sandbeds are a natural geological feature which contributes about 20% of the Lower Hunter/ Newcastle’s drinking water. The sandbeds run parallel to the coast and extend for about 25 kilometres between Newcastle and Port Stephens. Sandbeds can reach depths of up to 50 metres and average 20 metres in depth.
The Tomago Sandbeds are important for both day-to-day water supply and backup supply and storage because of the high capacity storage provided.
Anna Bay Sandbeds. The Anna Bay sandbeds is made up of a series of water bores. It has been estimated that the sustainable yield is 7 megalitres per day, however, the aquifer can be used to supply much higher flow rates in the short term because provided that the average extraction is kept at no more than the sustainable yield of 7 megalitres per day.