The Project Environment

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Shavonne Floyd
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1 Section 6 The Project Environment Section 6.1 Marine Environment Located at latitude 35 S on the south coast of WA, the marine flora and fauna of the Albany area are primarily temperate species with a small proportion of endemic species. There are also some tropical species (Wells et al., 1990). The King and Kalgan Rivers, Oyster Harbour, Princess Royal Harbour and King George Sound present a full range of salinities as well as a range of exposures providing habitat diversity. As a result of this habitat diversity, the Albany area displays a similarly diverse array of marine flora and fauna (Wells et al., 1990). Despite marine influences Oyster Harbour and Princess Royal Harbour display characteristics typical of estuarine ecosystems. The salinity of both harbours is close to that of marine waters (35 ppt), but Oyster Harbour in particular can change seasonally with fluctuation of inflowing freshwater leading to stratification in both salinity and temperature (Waterways Commission, 1995). Princess Royal Harbour is generally well mixed vertically and displays weak stratification. Shallow areas in estuarine ecosystems provide a variety of diverse and abundant habitats. Shallow subtidal ecosystems allow light to penetrate the water column and provide for the presence of perennial primary producing plants. The presence of perennial primary producers provides key habitat for a range of obligate and associated aquatic communities. Sheltered inter- and sub-tidal habitats provide important reproductive and nursery areas for a variety of estuarine and marine organisms. The shallow inter-tidal sandbanks and mudflats off the western and southern shores of Princess Royal Harbour are rich feeding areas for water birds. The Albany Port expansions are restricted to the northern shore of Princess Royal Harbour and a channel section within King George Sound. Plumes may occasionally be visible in Oyster Harbour during the proposed dredging, however, their intensity and duration will be such that no detectible effects on benthic biota or their habitats are predicted. The Project is therefore not anticipated to impact the sensitive suband inter-tidal communities in Oyster Harbour, or on the western and southern shores of Princess Royal Harbour. The marine flora related to the dredging and offshore disposal of excess dredge material are outlined in Section 6.5 and Section

2 Section 6.2 Geology, Landform and Bathymetry The Port of Albany was established through dredging and reclamation programmes in the vicinity of the Port Jetty. Most of the northern shore of Princess Royal Harbour has been reclaimed to facilitate industrial land for the City of Albany (Figure 6.1). Much of this area is now utilised for industrial and recreational purposes. Dredging commenced in 1893 and subsequent development dredging occurred in and The dredging areas were further extended in , 1967 and and a small maintenance programme in 1985 to clear silt from a large storm event in Surplus dredge material from the dredging was stockpiled on land for the purpose of reclamation and Port expansion. Recent capital and maintenance dredging occurred from November 2000 to May 2001 for the construction of berths 5 and 6. The Albany Port basin and entrance channel is currently dredged to a depth of m CD. Water depth within Princess Royal Harbour becomes progressively shallower in the southern and western areas of the Harbour due to the presence of a wide sandy inter-tidal shelf of less than two metres depth. The bathymetry of King George Sound is highly variable and relatively shallow (5-40 m). There has been some indication of occasional fragmented, unconsolidated limestone material belying the sandy sediments in some small localised areas in a previous study (ATA Environmental, 2000). In February 2005, the channel extending from the proposed berth 7 to the 20 m contour was probed up to 7 m into the seabed (JFA Consultants, 2005a) in order to define a channel with a low risk of encountering belying bedrock. Probe refusal occurred in the proposed berth 7 location and south of Gio Batta Patch, however subsequent seismic reflection surveys did not identify any limestone or granitic bedrock within the dredge profile. Dive observations (JFA Consultants, 2005a) described the material from the existing harbour and channel as a dark grey, fine to medium grained sand with minimal organic material and the material offshore as clean white sand. Bathymetric data sets of King George Sound and Princess Royal Harbour derived from several sources including Geoscience Australia and oil company surveys were updated with bathymetry data provided by JFA and used during ocean circulation modelling (GEMS, 2007). The bathymetry of King George Sound and the Port area in Princess Royal Harbour is provided in Figure

3 N Figure C 3.1 Geomorphological Overview of the Northern Shore of Princess Royal Harbour.

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5 Figure 6.2 Bathymetry of King George Sound and Port Area in Princess Royal Harbour.

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RECALLING Paragraph b of Article 13 of the Convention on the Protection of the Marine Environment of the Baltic Sea Area, 1974 (Helsinki Convention),

RECALLING Paragraph b of Article 13 of the Convention on the Protection of the Marine Environment of the Baltic Sea Area, 1974 (Helsinki Convention), CONVENTION ON THE PROTECTION OF THE MARINE ENVIRONMENT OF THE BALTIC SEA AREA HELSINKI COMMISSION - Baltic Marine HELCOM 19/98 Environment Protection Commission 15/1 Annex 3 19th Meeting Helsinki, 23-27