Water Kit - Hunter Water

1.2 the importance of catchments
Natural catchments direct runoff water to creeks, rivers, lakes, aquifiers and the ocean
What is a catchment?
A catchment is the area of land that
supplies surface water to a common
collection point - usually a creek, river,
dam, ocean or aquifier. Typically,
catchments are bordered by high
points like hills or ridges that direct the
flow of water.
Catchments can vary in scale from
the suburb you live in through to entire
regions covering thousands of
square kilometres. Many smaller
catchments can be located within one
large catchment.
Catchments may be completely
natural, or a combination of bushland,
agricultural, industrial and urban areas.
Typical coastal urban catchment land use zones
The types of land use and surfaces
found in a catchment will have a major
effect on the quality and quantity of
water found in the catchment zone.
The quality of our fresh water supplies
depends on the health of our catchments.
HUNTER WATER’S AREA OF
OPERATIONS
Hunter Water provides water and
wastewater services to towns and cities
across the Lower Hunter, Lake Macquarie
and Port Stephens catchments. This area
of operations includes the five local
government areas of Newcastle, Lake
Macquarie, Port Stephens, Maitland
and Cessnock.
Hunter Water’s collection, storage and
treatment of water is centred around
the Williams River and adjacent Port
Stephens catchments. The three main
water storages are Chichester Dam,
Grahamstown Dam and the Tomago
Sandbeds.
Chichester Dam is located north of
Dungog. The catchment for Chicester
Dam is within the Barrington Tops
National Park and is a declared
wilderness area. It is one of the most
pristine catchments in Australia, with
large areas unaffected by human
activity. This is reflected in the quality
of the water drawn from the dam.
Water released from Chichester Dam
flows into the Chichester River and the
Williams River. The Williams River
catchment is relatively undeveloped
but supports a range of activities and
land uses including agriculture,
residential and urban developments,
recreation and tourism.
Further downstream, near Seaham,
water from the Williams River can be
transferred to Grahamstown Dam via the
Balickera Canal. The Williams River
Grahamstown Dam system is an
important component of the Lower
Hunter’s water supply.
Grahamstown Dam is the region’s major
urban water supply. It is an off-river
storage with water supplied from its own
catchment and the Williams River.
The third source is underground water
from the Tomago Sandbeds in the
Port Stephens catchment. Water from
the sandbeds is extracted by pumps
and sent for treatment at the
Grahamstown/Tomago Water Treatment
Plant. Smaller treatment plants at Lemon
Tree Passage, Glovers Hill and Anna Bay
extract water from nearby aquifiers.
The first map shows Hunter Water’s
area of operations. While the Williams
River catchment is not part of Hunter
Water’s area of operations in terms of its
service to customers, it is of great
importance due to the location of
Chichester Dam.
The following three maps on the
opposite page show the Port Stephens,
Hunter and Lake Macquarie
catchments. The dashed lines in the top
and middle maps show the boundary of
Hunter Water’s area of operations.
Water kit . ssS . 001 . april 2010
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