State of the Bay Report 2011-Final.pdf - Anchor Environmental

State of Saldanha Bay & Langebaan Lagoon 2011
Activities & discharges
facilities for the proposed Sunrise Energy LPG in Saldanha and these will be outlined in the scoping
report for the study due for release at the end of July 2012 (Claire Alborough, ERM, pers. comm.).
Potential impacts to the marine environment, that need to be considered, include changes in water
quality, change in sediment dynamics, impacts to benthic fauna, visual and landscape impacts, noise,
socio-economic impacts and cumulative impacts (ERM 2010). Impacts to the marine environment
may also be incurred as a result of storm water effluents from the on-shore storage facility.
3.3.4 Development of the Salamander Bay Boat yard
The Special Forces Regiment of the South African National Defence Force (SANDF) commenced the
construction of a boat park in Salamander Bay at the entrance to Langebaan Lagoon in 2009,
designed to house boats belonging to the regiment (Figure 3.10). The shores within Salamander Bay
are dominated by sandy beaches and are considered sheltered. Soft bottom habitat dominates the
subtidal benthos, which attains depths of no greater than 5 m. In order to increase the size of the
boat house an area of 550 m 2 within the rocky intertidal zone was excavated and an area of 275 m 2
of subtidal soft bottom habitat was dredged to allow for the placement of two column footings and
25 wet column bases.
Figure 3.10. The Salamander Bay boatpark in Saldanha (central strip of the picture).
The construction activities commenced before an Environmental Impact Assessment (EIA)
had been conducted. An EIA was commissioned retrospectively in terms of section 24G of the
National Environmental Management Act (Act no 107 of 1998). A marine ecology report was
compiled as part of the EIA to assess the impacts which had already occurred through the
development of the boat yard, and the potential impacts which may result through the long-term
use of the facility. The excavation of the intertidal and subtidal areas involved the mechanical
removal of large boulders and the dredging of sediments. It was indicated that the impact of this
excavation was of a high consequence as it resulted in a permanent loss of habitat and organisms in
both the intertidal and subtidal zones. However, the affected area was acknowledged to be small,
and the habitat common to the Saldanha Bay system.
The dredging of the subtidal zone, which took place between May 2009 and May 2010, led
to the release of a grey coloured sediment plume. Chemical analyses of the water and the dredged
sediment indicated that there had been no contamination of cadmium or arsenic and only slightly
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