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

State of Saldanha Bay & Langebaan Lagoon 2011
List of Figures
Figure 4.26.
Figure 4.27.
Figure 4.28.
Figure 4.29.
Figure 4.30.
Figure 4.31.
Figure 4.32.
Figure 4.33.
Monthly trends in the concentration of Ammonia Nitrate in effluent from
Langebaan WWTW, June 2009 - December 2011. Allowable limits as specified in
terms of a General Authorisation under the National Water Act 1998 are
represented by the red line. ..................................................................................... 45
Monthly trends in the concentration of Nitrate Nitrogen in effluent from
Langebaan WWTW, June 2009 - December 2011. Allowable limits as specified in
terms of a General Authorisation under the National Water Act 1998 are
represented by the red line. ..................................................................................... 45
Monthly trends in the concentration of Orthophosphate in effluent from
Langebaan WWTW, June 2009 - December 2011. Allowable limits as specified in
terms of a General Authorisation under the National Water Act 1998 are
represented by the red line. ..................................................................................... 46
Monthly trends in the concentration of Free Active Chlorine in effluent from
Langebaan WWTW, June 2009 - December 2011. Allowable limits as specified in
terms of a General Authorisation under the National Water Act 1998 are
represented by the red line. ..................................................................................... 46
Spatial extent of residential and industrial areas surrounding Saldanha Bay and
Langebaan Lagoon from which storm water runoff is likely to enter the sea (areas
outlined in white). Note that runoff from the Port of Saldanha and ore terminal
have been excluded as it is now reportedly all diverted to storm water evaporation
ponds. ....................................................................................................................... 48
Location of seawater intakes and discharges for seafood processing in Saldanha
Bay together with location of current and proposed mariculture operations ......... 50
Total monthly discharge of fresh fish processing effluent (FFP) disposed to sea by
Sea Harvest from January 2001 to March 2007. ...................................................... 53
Monthly trends in the numbers of Faecal coliforms in effluent from the Sea Harvest
fresh fish processing effluent (FFP) discharged into Small Bay in the period Feb 201
to Dec 2011. .............................................................................................................. 54
Figure 4.34. Allocated mariculture concession areas in Saldanha Bay 2010. .............................. 56
Figure 4.35. Overall annual mussel productivity (tons) in Saldanha Bay between 2000 and 2010
(source: DAFF 2011) .................................................................................................. 56
Figure 5.1.
Figure 5.2.
Figure 5.3.
Figure 5.4.
Schematic representation of the surface currents and circulation of Saldanha Bay
(A) prior to the harbour development (Pre-1973) and (B) after construction of the
causeway and iron-ore terminal (Present). (Adapted from Shannon and Stander
1977 and Weeks et al. 1991a) .................................................................................. 58
Faecal coliform and E. coli counts at 4 of the 10 sampling stations within Small Bay
(Feb 1999-Feb 2012). A downward slope of the regression (solid red and blue
lines) is indicative of improving water quality, while an upward slope in these lines
in indicative of decreasing water quality. ................................................................. 66
Faecal coliform and E. coli logarithmic counts at 3 of the 10 sampling stations
within Small Bay (Feb 1999-Feb 2012). A downward slope of the regression (solid
red and blue lines) is indicative of improving water quality, while an upward slope
in these lines in indicative of decreasing water quality............................................ 67
Faecal coliform and E. coli logarithmic counts at 4 of the 10 sampling stations
within Big Bay (Feb 1999-Feb 2012). A downward slope of the regression (solid red
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