coaltech upper olifants river catchment wetland inventory ...

• Dwars-in-die-wegspruit at the low water bridge before the confluence with
Trichardtspruit;
• Olifants River at Control Point B1H018;
• Upper reaches of the Olifants River;
• Tributary of the Klein Olifants River at the bridge on the road between Hendrina and
Middelburg;
• Klein Olifants River at Control Point B1H012; and
• Arendsfonteinspruit 2km upstream of the Middelburg Dam.
While the instream habitat significantly decreased at:
• Trichardspruit downstream of the Syferfontein Colliery; and
• Tributary upstream of the Klein Olifants River, upstream of the Hendrina Power
Station and the Boschmanskop Dam (ECOSUN 2006).
Comparison to the previous year’s results (2005) showed few significant changes in the
habitat integrity. The IHAS showed that the modifications to habitat integrity are mostly large
to critical in the catchment (Classes D to F). In some areas basic ecosystem functions have
been destroyed (ECOSUN 2006).
The Ecological State Classes obtained from the SASS results indicated both significant
spatial and temporal variation in the catchment. The significant variation can be attributed to
the complexity of the variety of impacts in the catchment, including: effluent, channel
modification, exotic vegetation, competition from exotic fish species and veld fires (ECOSUN
2006).
The Sediment Contaminant Analysis showed significant decreases in analytes in the
sediments, due to the high flows experienced before the 2006 analysis in the catchment. The
Olifants River upstream of the Koringspruit confluence had the highest concentration of
analytes in the Witbank Dam catchment and a tributary of the Klein Olifants River, as well as
a section of the Klein Olifants River which had the highest analyte concentration in
Middelburg Dam (ECOSUN 2006).
The study only reflects the biotic integrity of the study area at the time of the survey. The
possible impact of the biotic integrity on the rivers and streams were not analysed and will
form part of a later phase of the study (ECOSUN 2006).
Wetland Database for UORC - 47 -