FORSTER OUTFALL

Click the photograph for a enlarged view

Physical Environment

Landscape

Shark Point appears to be a seaward extension of Conger formation rocks which consist mainly of sandstone and conglomerate (Newcastle Geological Series Sheet SI 56 – 2). To the south are Janies Corner and Seven Mile Beach. To the north is a small pocket beach (Shark Beach) and then the rocky headlands of Cape Hawke.

Bathymetry & Substrate

The pipeline is encased in concrete ornamented with small boulders with the flat horizontal surface of the encased pipeline providing physically different habitat to that of the surrounding rocks. Water depth in the vicinity of the outfall was 3 to 6 m with a small area of reef consisting of submerged boulders

Currents, Winds and Waves

Oceanographic investigations (PWD 1979, MHL618 1992) indicate:

• a seaward flowing current running along the northern side of Shark Point and extending out to the tip of the point

• a second current flowing north parallel to the shoreline and away from the existing outfall site

• an anti-clockwise recirculation pattern within the surf zone at the southern end of Shark Beach.

• during low wave activity and on a rising tide, currents flow predominantly in a north-east direction

• in periods of high wave activity the surf zone extends further offshore

• a strong correlation between local currents and local wind data - effluent is transported to the end of the point 60% of the time and currents flowing from the outfall toward Seven Mile Beach would occur approximately 25% of the time (TEL 1993).

Outfall Site

Outfall Site

Forster

(Fost_5) Last updated May 2000