APPENDIX 9 POSSIBLE INTERCHANGES ALONG THE DE BEERS PASS ROUTE AVIFAUNAL ASSESSMENT

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1 APPENDIX 9 POSSIBLE INTERCHANGES ALONG THE DE BEERS PASS ROUTE AVIFAUNAL ASSESSMENT 1 EXECUTIVE SUMMARY This appendix assesses, from an avifaunal perspective, the expected impacts of seven possible interchanges along the proposed De Beers Pass Route. This analysis suggests that of the seven possible interchanges, only the Lincoln Interchange presents a potentially problematic situation relevant to avifauna. This is due to its immediate proximity to Lincoln Dam and its associated and abundant waterbird population. Consideration should be given to locating the interchange further to the north-east. Such a repositioning, of course, would also require a deviation to the proposed route. This interchange re-location and associated route deviation, however, would be congruent with the proposed extension of the existing possible Lincoln Pan Deviation (see Appendix 8). As a further positive improvement, the interchange re-location and associated route deviation would shift the road and intersection further away from the known Secretarybird nest (a formally threatened species). A dam, however, in the final analysis, is an artificial structure. It can have some biodiversity value, as in the case here, but likely at the cost of proper wetland functioning along the original watercourse. Farm dams are also not rare features in this landscape. 2 INTRODUCTION This appendix assesses, from an avifaunal perspective, the expected impacts of seven possible interchanges along the proposed De Beers Pass Route option of the National Road 3 Keeversfontein to Warden Toll Concession (N3TC). These seven deviation sections are named, from south to north: Ingula on Dev 2 Option 3, Ingula on Dev 4 option 3, Ingula Access Road, Tandjiesberg/Afgunst, Schreiners Claim/Collings Pass Road, Lincoln Interchange and Steyn/Susanna. This report comprises an addendum ( Appendix 9 ) to the final avifaunal specialist report of the environmental impact assessment for the proposed National Road 3: Keeversfontein to Warden (De Beers Pass Section) (DEA ref. no. 12/12/20/1992). Table 1. Details of the seven possible interchanges on the potential De Beers Pass Route. De Beer's Pass route : Possible Interchanges Interchange Name Road No. Farm Name Position Lat. Long.

2 Ingula Access Road Ingula access road Strathmorn Ingula (on Dev 4 Option 3) D48 Strathmorn Ingula (on Dev 2 Option 3) D48 Strathmorn Tandjiesberg/Afgunst S922 Afgunst Schreiners Claim/Collings Pass Road S692 Schreiners Claim Lincoln Interchange S18 (R722) Lincoln Steyn/Susanna S788 Susanna The typical configuration of an interchange is shown in Figure 1, i.e. the size and shape of the structure to be assessed. Figure 1. The typical configuration of an interchange.

3 The locations of the possible seven interchanges are shown in Figure 2 (see also Figure 1 of the main report). Figure 2. The locations of the seven possible interchanges. This assessment is based on field inspections of six of the seven possible interchanges (Steyn/Susanna was not visited). These were made in May 2013, although the sites, including Steyn/Susanna, were also familiar from previous work in the area during this project. The overall aim of this assessment is to identify any areas of avifaunal concern relevant to these interchanges. 3 DETAILS OF THE SEVEN POSSIBLE INTERCHANGES 3.1 Ingula Dev2 Option 3 & Ingula Dev4 Option 3 These two possible interchanges are essentially located directly adjacent to one another and can be assessed simultaneously. The general area comprises natural grassland, patches of alien wattle trees and the existing De Beers Pass road and Ingula access road (Figure 3).

4 Figure 3. General view, from the north, of the possible Ingula Dev2 Option 3 & Ingula Dev4 Option 3 interchange area/s. The immediate area of the interchange is not considered of any particular local avifaunal significance. 3.2 Ingula Access road The general area comprises natural grassland, patches of alien trees and two small dams (Figure 4). Figure 4. General view, from the north, of the possible Ingula Access Road interchange area. The immediate area of the interchange is not considered of any particular local avifaunal significance. 3.3 Tandjiesberg/Afgunst The general area comprises crop fields on the north side of the existing road (S922) and natural grassland on the south side (Figures 5 and 6). A fairly major watercourse occurs at the extreme eastern edge of the interchange area and care should be taken that the interchange does not impinge directly into the area of this watercourse.

5 Figure 5. General view, from the west, of the possible Tandjiesberg/Afgunst interchange area (Nelson s Kop visible in the background in the right of the photo). Figure 6. Satellite image of the possible Tandjiesberg/Afgunst interchange area. Note the incorporation of the large watercourse within the orange line in the north. The immediate area of the interchange is not considered of any particular local avifaunal significance. 3.4 Schreiners Claim/Collings Pass Road The general area comprises natural grasslands on the north and south side of the existing road (S692) (Figures 7 and 8). There is also a large dam just south of (170 m away from) the existing road that would likely fall within the interchange footprint (Figures 8 and 9). Without access to a detailed configuration of the interchange layout, it is difficult to assess how the interchange will accommodate this feature. There is also a small pan to the north of the existing road, and situated just west of the proposed De Beers Pass route (Figure 8), but this likely lies just outside the potential footprint of

6 the interchange. In addition, neither the dam not the pan can be considered of particular avifaunal importance. Figure 7. General view, from the east, of the possible Schreiners Claim/Collings Pass Road interchange area. Figure 8. Satellite image of the possible Tandjiesberg/Afgunst interchange area showing the proposed route, existing S18 (R722) and both the dam and pan mentioned in the text.

7 Figure 9. View of the large dam situated south of the existing road, at the possible Schreiners Claim/Collings Pass Road interchange area. The immediate area of the interchange is not considered of any particular local avifaunal significance. 3.5 Lincoln Interchange Unlike the other deviations considered in this appendix, the Lincoln Interchange (Figures 10 and 11) is considered of avifaunal concern. This is due to a fairly large farm dam (Figure 12) that is particularly well vegetated and which supports a fairly rich assemblage of waterbirds. This dam would be situated virtually within the configuration of the interchange (Figure 11). Indeed, the construction of the interchange would likely require the destruction of the dam. Should it be left intact, its proximity to the interchange and the road would result is severe disturbance to the waterbird population and likely a high level of bird mortality through collisions with motor vehicles and fences/overhead lines along the road route. Figure 10. General view, from the east, of the possible Lincoln Interchange area. Lincoln Dam is visible in the background of the photo just to the right of the road in the distance.

8 Figure 11. Satellite image of the possible Lincoln Interchange area showing the proposed route, the existing S18 (R722), Lincoln Dam, Lincoln Pan and the Secretarybird nest. Figure 12. View, from the south, of Lincoln Dam, showing its well-vegetated nature. Consideration therefore should be given to locating the interchange further to the north-east. Such a re-positioning, of course, would also require a deviation to the proposed route. An obvious problem with such a re-routing would be that it would move the road closer to the watercourse situated east of the existing route, perhaps unacceptably so (Figure 11). There are, however, several possible advantages to such a re-routing. This interchange re-location and associated route deviation would be congruent with the proposed extension of the existing possible Lincoln Pan Deviation (Figure 11 and see Appendix 8). As a further positive improvement, the interchange re-location and associated route deviation would shift the road and intersection further away from the known Secretarybird nest, a formally threatened species (already discussed in the main report) (Figure 11).

9 The immediate area of the Lincoln Interchange is considered of avifaunal concern. This is due to its immediate proximity to Lincoln Dam and its associated and abundant waterbird population. Consideration should be given to locating the interchange further to the north-east. Such a re-positioning, of course, would also require a deviation to the proposed route. This interchange re-location and associated route deviation, however, would be congruent with the proposed extension of the existing possible Lincoln Pan Deviation (see Appendix 8). As a further positive improvement, the interchange relocation and associated route deviation would shift the road and intersection further away from the known Secretarybird nest (a formally threatened species). 3.6 Steyn/Susanna Although the Steyn/Susanna possible interchange was not investigated in the field, the area had been visited earlier in the broader project investigation and an examination using Google Earth does not suggest that the interchange area can be expected to be of any particular avifauna concern. The area north and south of the existing road (S788) in this area, however, does appear to comprise natural grassland. There are also two small farm dams situated about 300 m east of the proposed De Beers Pass Route at the interchange site. There will likely be an opportunity to examine this site in the field in the near future and hopefully in time to incorporate the results before the final report on the project is completed. 4 CONCLUSION This analysis suggests that of the seven possible interchanges, only the Lincoln Interchange presents a potentially problematic situation relevant to avifauna. Re-location of the interchange to the north-east, and an associated re-routing of the road option, are suggested as possible solutions to this problem (that also carry some additional potential advantages from an avifaunal perspective). A dam, however, in the final analysis, is an artificial structure. It can have some biodiversity value, as in the case here, but likely at the cost of proper wetland functioning along the original watercourse. Farm dams are also not rare features in this landscape. David Allan c/o Curator of Ornithology Durban Natural Science Museum Tel Cell davidallan@telkomsa.net