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

State of Saldanha Bay & Langebaan Lagoon 2011
Activities & discharges
26% of the time (Figure 3.17). Chemical Oxygen Demand is commonly used to indirectly measure
the amount of organic compounds in water.
Figure 3.16. Monthly trends in the numbers of Total Suspended Solids in effluent released from the
Saldanha WWTW, April 2003 - December 2011. Allowable limits as specified in terms of a
General Authorisation under the National Water Act 1998 are represented by the dashed red
line.
Figure 3.17.
Monthly trends in the numbers of Chemical Oxygen Demand in effluent released from the
Saldanha WWTW, April 2003 - December 2011. Allowable limits as specified in terms of a
General Authorisation under the National Water Act 1998 are represented by the red line.
A worrying sign is the levels of Ammonia Nitrogen discharged which are consistently above
the allowable margin of 3 mg/l; allowable limits being exceeded 94% of the time (Figure 3.18).
Nitrate Nitrogen limits were exceeded on 17% of the occasions (Figure 3.19).
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