David Hoare Consulting cc Biodiversity Assessments, Vegetation Description and Mapping & Species Surveys

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1 PROPOSED N2 WILD COAST TOLL HIGHWAY: ADDENDUM TO SPECIALIST SCREENING STUDY ON POTENTIAL IMPACTS OF ALTERNATIVE ALIGNMENTS ON FLORA AND VEGETATION: ADDITIONAL PROPOSED ALIGNMENTS Prepared for CCA Environmental PO Box CALEDON SQUARE 7905 Prepared by: David Hoare Draft version 4 21 February 2007 David Hoare Consulting cc Biodiversity Assessments, Vegetation Description and Mapping & Species Surveys

2 i EXECUTIVE SUMMARY This report serves as an addendum to an earlier screening report, dated 27 February 2006, and presents the findings of an ecological screening study that was undertaken of additional alternatives for the proposed N2 Wild Coast Toll Highway for the section of road from Mthatha to Port Shepstone. Three additional s are considered, and are analysed here using the same approach as in the original study. The three s are as follows: 1. Coastal Mzamba, which is a variation of SANRAL s preferred between Lusikisiki and the Mthamvuna River, 2. WESSA, a proposal made by Dr Keith Cooper of WESSA, 3. Gallagher, a proposal made by Mr Mark Gallagher. This report analyses the potential risk to the botanical receiving environment of these three s. The Coastal Mzamba and the WESSA are analysed as greenfields s from Lusikisiki to the Mthamvuna River and compared to SANRAL s preferred greenfields alignment as presented in the earlier report. The Mark Gallagher is analysed from Mthatha to Port Shepstone and is compared to SANRAL s preferred as well as to the alternative of upgrading the existing N2 between these two centres. With regard to the greenfields alignments between Lusikisiki and the Mthamvuna River, the WESSA contains a lower proportion of sensitive habitats within the greenfields section than the Coastal Mzamba and the SANRAL preferred alignment. A 2 km wide (1 km on each side of the proposed road) was used for illustration purposes to demonstrate the amount of sensitive habitat within a short distance of the alternative s. There is less area of high sensitivity within 1 km of the WESSA within the greenfields section than either the SANRAL preferred or the Coastal Mzamba. The SANRAL preferred alignment affects less habitat of high sensitivity within the greenfields section than the Coastal Mzamba. Within the greenfields section the overall sensitivity rating for the WESSA is MEDIUM, whereas the sensitivity rating for the SANRAL preferred and the Coastal Mzamba is MEDIUM-HIGH. Similarly, the overall rating of risk to the botanical receiving environment for the WESSA is MEDIUM, whereas for the SANRAL preferred and the Coastal Mzamba it is MEDIUM-HIGH.

3 ii For the entire from Mthatha to Port Shepstone, the Mark Gallagher has approximately the same proportion of habitats classified as having high sensitivity as the existing N2. Both these s have lower proportions of high sensitivity habitats than the SANRAL preferred. The Mark Gallagher and the existing N2 are also relatively similar in the proportions of sensitive habitats that could potentially be affected up to 1 km from the proposed road, whereas the SANRAL preferred would affect a moderately higher proportion of sensitive ecosystems. For the entire from Mthatha to Port Shepstone the overall sensitivity of the Mark Gallagher, the existing N2 and the SANRAL preferred is rated as MEDIUM. The risk to the botanical receiving environment is rated as MEDIUM for the Mark Gallagher and the existing N2, whereas for the SANRAL preferred it is rated as MEDIUM-HIGH.

4 iii TABLE OF CONTENTS EXECUTIVE SUMMARY... i 1. INTRODUCTION Methods Calculation of overall sensitivity score ANALYSIS OF THE COASTAL MZAMBA AND WESSA ROUTES Impact of entire distance from Mthatha to Port Shepstone Impact within greenfields section Risk assessment for entire distance (Mthatha to Port Shepstone) Risk assessment within greenfields section ANALYSIS OF THE MARK GALLAGHER ROUTE Potential impact of Risk assessment of CONCLUSION Summary of assessment within greenfields section Summary of assessment for entire distance... 14

5 1 1. INTRODUCTION The South African National Roads Agency Limited (SANRAL) intends to develop a toll road on the N2 between the Gonubie Interchange near East London and the Isipingo Interchange south of Durban. This report serves as an addendum to an earlier screening report on the potential botanical impacts of alternatives for the proposed N2 Wild Coast Toll Highway for the section of road from Mthatha to Port Shepstone. The earlier screening report was dated 27 February 2006 and was submitted as part of the scoping phase of the environmental impact assessment (EIA) of the project. Three additional greenfields s are now being considered. The first is a variation of SANRAL s proposed greenfields alignment between Lusikisiki and the Mthamvuna River while the remaining two s were proposed by other parties in an attempt, primarily, to minimise the potential environmental impact of the new road on the Pondoland Centre of Endemism. The additional s being considered are as follows (see Figure 1 for map of s): 4. Coastal Mzamba, 5. WESSA, a proposal made by Dr Keith Cooper of WESSA, 6. Gallagher, a proposal made by Mr Mark Gallagher. This report analyses the potential risk to the botanical receiving environment of these three s and compares them to SANRAL s preferred as presented in the earlier report. The Coastal Mzamba and the WESSA are analysed as greenfields s from Lusikisiki to the Mthamvuna River and compared to SANRAL s preferred greenfields alignment as presented in the earlier report. The Gallagher is analysed from Mthatha to Port Shepstone and is compared to SANRAL s preferred as well as the alternative of upgrading the existing N2 between these two centres. 1.1 Methods The analysis of these alignments follows the same methodology as described in the main botanical screening report (see section 6.4 of the original botanical screening report). In the original botanical screening report an ecological sensitivity map of the vegetation of

6 2 the study area was produced. The different alignments could then be assessed according to the proportions of different vegetation sensitivity classes would be affected by a particular. The same approach was used here based on the same vegetation sensitivity map. In each case for the current assessment, the entire distance along the greenfields section between Lusikisiki and the Mthamvuna River is assessed followed by an assessment of the total distance from Mthatha to Port Shepstone. A third analysis considers a 1 km potential affected zone on each side of the proposed s to assess the potential effect of secondary impacts on the conservation status of affected vegetation types. For this a 2 km wide (1 km on each side of the proposed road) is used for illustration purposes to demonstrate the amount of sensitive habitat within a short distance of the alternative s, although secondary impacts may act on a greater distance than this. The s were examined on a field trip undertaken between the 15 th and 19 th of October Calculation of overall sensitivity score It was necessary to classify each as being low, low-medium, medium, medium-high or high sensitivity. This was in order to facilitate comparisons between different s in terms of the potential impact on the botanical receiving environment. This sensitivity assessment is intended to be a summary of the vegetation sensitivity. Depictions of vegetation sensitivity are given in map form in Figures 1 and 2 in this report and Figure 3 within the original botanical screening report. The relative proportions of habitat within different sensitivity classes within a particular is therefore classified, objectively, into a single value or qualitative expression, e.g. 30% = medium, in order to facilitate comparisons between different s in terms of the potential impact on the botanical receiving environment. In the original botanical screening report the overall sensitivity score for each was not formalised. This was found to be unsatisfactory and a more objective and formalised approach was required. A quantitative summary of the vegetation sensitivity of the different s was devised in order to compare the different alternatives. The s therefore had to be ranked according to overall sensitivity. The rankings given is expressed in a relative form and is based on the proportion of each in different vegetation sensitivity classes. If

7 3 vegetation sensitivity can be expressed as a percentage rather than a qualitative value then the following scale may apply to different areas of vegetation: Vegetation sensitivity class (from vegetation sensitivity map) Percentage sensitivity Average percentage value for sensitivity class LOW 0 20% 10% MEDIUM 20 80% 50% HIGH % 90% In this scale MEDIUM vegetation sensitivity is centred around 50% and the HIGH and LOW vegetation sensitivity classes are allocated the same proportions on opposite ends of the scale. In order to reduce the entire to a single expression of sensitivity then it is necessary to add the average vegetation sensitivity percentage of the different sections of the. This can be done by multiplying the vegetation sensitivity of the different sections of the by the average vegetation sensitivity percentage given above and then adding the results. Since the sensitivity in the tables for the different sections is given as proportions, the result of adding the sensitivity percentages can also be expressed as a percentage. The scale takes into account that if all of the were to occur within habitats with a high sensitivity then the overall sensitivity of the would be close to 100%. Similarly, if the had no habitat within high or medium sensitivity habitats then it would have an overall sensitivity close to 0%. These overall scores can, in turn, be reduced to a single expression of sensitivity, as follows: Overall sensitivity score Overall rating 0 10% LOW 10 25% LOW-MEDIUM 25 45% MEDIUM 45 70% MEDIUM-HIGH % HIGH In order to compensate for the fact that small areas of sensitive habitat may indicate high overall sensitivity, the scale is not linear but is skewed in a precautionary manner towards higher vegetation sensitivity by increasing class interval increments towards the upper end of the scale.

8 4 For the risk assessment, an evaluation of the potential risk to sensitive habitats within the botanical receiving environment, a similar approach is taken with the assumption that increased area of sensitive habitat potentially affected by the results in increased likelihood of damage to sensitive ecological habitats. It is important to note that all s assessed within the greenfields section of the study area WILL have an impact on some sensitive habitats within the botanical receiving environment. However, some s will only affect small areas of sensitive habitat and others will affect larger areas of sensitive habitat. The approach here is to rate the s according to the EXTENT of potential impact on sensitive habitats within the botanical receiving environment, thus taking into account both the probability and consequences of potential impacts (see Box below). BOX 1: SOME DEFINITIONS OF RISK Risk, definition of: The possibility, expectation or quantifiable likelihood of loss. Exposure to a chance of loss or damage. It is a function of the probability and the consequences of harm. Risk assessment, definition of: Within the context of an environmental study, a report that shows natural assets, vulnerabilities, likelihood of damage, summaries of possible defensive measures and estimated probable savings from better protection. A "risk analysis" is the process of arriving at a risk assessment, which is also called a "threat and risk assessment." A "threat" is, from the point of view of the natural environment, a harmful act such as the construction of infrastructure or degradation from over-utilization. A "risk" is the expectation that a threat may succeed and the potential damage that can occur.

9 5 2. ANALYSIS OF THE COASTAL MZAMBA AND WESSA ROUTES This section of the report compares the Coastal Mzamba and the WESSA to SANRAL s preferred greenfields between Lusikisiki and the Mthamvuna River. These s are shown in Figure 1 along with vegetation sensitivity in the study area. Each is assessed according to the proportions of sensitive habitats that they would traverse. In Figure 1 the darker colours equate to more sensitive vegetation. The Coastal Mzamba in Figure 1 continues along the SANRAL preferred alignment for the remainder of its distance (Figure 1). Figure 1: Proposed s between Lusikisiki and Port Edward showing vegetation sensitivity.

10 6 2.1 Impact of entire distance from Mthatha to Port Shepstone Table 1 shows the proportions of each of these s in different sensitivity classes for the entire distance from Mthatha to Port Shepstone, including existing sections of road. The WESSA alignment includes 91.3 km of greenfields section, whereas the Coastal Mzamba and SANRAL preferred alignment include 78.3 km and 78.0 km of greenfields sections, respectively (Table 1). There are, however, existing roads (parts of the R61), gravel tracks, etc. within the greenfields area for which there is an existing impact. If these are taken into account then the three options are relatively similar with respect to the distances across entirely untransformed habitats within the greenfields section (see Table 1, brackets in second to last column for distances without such existing disturbances). This includes only formal roads, as shown in the 1: topocadastral maps supplied by the Surveyor General. The total distance of sensitive features for these three alignments is similar across the entire distance from Mthatha to Port Shepstone, the Coastal Mzamba having slightly more distance of sensitive features at 88.8 km versus km for the other two alignments (Table 1). For all three alignments, the outside the greenfields section northwards from the Mthamvuna River to Port Shepstone and southwards from Lusikisiki to Mthatha is identical. The differences in proportions of sensitive features between the three s is therefore entirely due to the differences in alignment along the greenfields section. These are examined in more detail in the following sub-section of this report. Table 1: Lengths and proportions of alternative s in different sensitivity classes for ENTIRE DISTANCE from Mthatha to Port Shepstone. Route Proportion of sensitive vegetation crossed by over entire distance Total distance (Mthatha to Port Shepstone) (km) Total distance of sensitive features (km) Portion in greenfields section (Lusikisiki to Mthamvuna River) (km)* High Medium WESSA (54.5) Coastal (57.1) Mzamba SANRAL preferred (51.5) *distance in brackets refers to sections without any existing roads, tracks, etc. Low

11 7 2.2 Impact within greenfields section Table 2 shows the sensitivity, i.e. the proportions of each of these s in different vegetation sensitivity classes for the greenfields section of these three s from Lusikisiki to the Mthamvuna River. The WESSA would traverse less proportion of habitats classified as having medium or high sensitivity within the greenfields section (Table 2). Approximately 51.7% of the WESSA would traverse areas with combined medium and high sensitivity (Table 2). However, only 13.9 km of the 25.6 km of the WESSA within areas classified as having high sensitivity (mostly within the PCE) would be situated in areas that contain no existing roads (as defined in the section of this report above). In comparison, 64.4% of the Coastal Mzamba and 62.5% of the SANRAL preferred occur in combined medium and high sensitivity areas (Table 2). The SANRAL preferred would have lower proportions of its alignment in areas with no existing roads, vehicle tracks, etc within sensitive areas compared to the Coastal Mzamba i.e km versus 41.7 km (Table 2) and both of these have more distance within sensitive areas than the WESSA (13.9 km). Relative to one another, the WESSA alignment therefore potentially has a MEDIUM impact on the greenfields botanical receiving environment whereas the other two have a MEDIUM- HIGH impact on the greenfields botanical receiving environment. Table 2: Route sensitivity for GREENFIELDS section between Lusikisiki and the Mthamvuna River. Route Proportion of sensitive vegetation crossed by Rating Total distance of sensitive features in greenfields section (km)* High Medium Low Overall sensitivity score WESSA 25.6 (13.9) MEDIUM Coastal Mzamba 43.5 (41.7) MEDIUM- HIGH SANRAL preferred 33.9 (24.4) MEDIUM- HIGH *distance in brackets refers to sections without any existing roads, tracks, etc. within sensitive environments within the greenfields section

12 8 2.3 Risk assessment for entire distance (Mthatha to Port Shepstone) The three s were assessed with respect to the potential impact on features classified as having high sensitivity that they may have up to a distance of 1 km from the proposed. The evaluation of impacts up to 1 km from the proposed gives an indication of the potential effect of secondary impacts on sensitive ecosystems. The three s are relatively similar in the proportions of sensitive features that could potentially be affected up to 1 km from the proposed road for the entire from Mthatha to Port Shepstone (Table 3), but the WESSA would affect a lower proportion of ecosystems in the high sensitivity class and a higher proportion in the low sensitivity class. The Coastal Mzamba and the SANRAL preferred are almost identical, with the SANRAL preferred affecting a marginally lower proportion of high sensitivity habitats (Table 3). For all three alignments, as indicated previously, the northwards from the Mthamvuna River to Port Shepstone and the southwards from Lusikisiki to Mthatha is identical. The differences in proportions of sensitive features between the three s within 1 km of the proposed s is therefore entirely due to the differences in alignment along the greenfields section. As before, these are examined in more detail in the following sub-section of this report. Table 3: Route sensitivity for ENTIRE ROUTE including a 1 km potential affected zone on each side to demonstrate the potential effect of secondary impacts for ENTIRE DISTANCE from Mthatha to Port Shepstone. Route Total distance of sensitive features in entire including 1km zone (km)* High Medium Low Total area of including 1km zone (ha) WESSA Coastal Mzamba SANRAL preferred

13 9 2.4 Risk assessment within greenfields section The WESSA would affect significantly less proportions of sensitive habitats up to 1 km from the proposed road (2 490 ha) than either the SANRAL preferred (8 816 ha) or the Coastal Mzamba (7 897 ha) within the greenfields section (Table 4). The WESSA would be marginally better than the other two alignments across the entire from Mthatha to Port Shepstone, but would be less likely to lead to secondary impacts within the greenfields section than either the SANRAL preferred or the Coastal Mzamba. The SANRAL preferred would be marginally less likely to lead to secondary impacts within the greenfields section than the Coastal Mzamba. Relative to one another, the WESSA alignment therefore potentially has a MEDIUM risk of having an impact on sensitive habitats within the greenfields botanical receiving environment whereas the other two have a MEDIUM-HIGH risk of having an impact on the greenfields botanical receiving environment. Table 4: Route sensitivity for GREENFIELDS between Lusikisiki and the Mthamvuna River, including a 1 km potential affected zone on each side to demonstrate the potential effect of secondary impacts. Route Total distance of sensitive features in greenfields section including 1km zone (km)* High Medium Low Total area of including 1km zone (ha) Overall sensitivity score Rating WESSA Coastal Mzamba SANRAL preferred MEDIUM MEDIUM- HIGH MEDIUM- HIGH

14 10 3. ANALYSIS OF THE MARK GALLAGHER ROUTE This section compares the Gallagher to two other s for the entire from Mthatha to Port Shepstone. The other two s are the proposed N2 Wild Coast Toll Highway (which incorporates SANRAL s preferred alignment for the greenfields between Lusikisiki and the Mthamvuna River) and the upgrading of the existing N2 from Mthatha to Port Shepstone. These s are shown in Figure 2 along with vegetation sensitivity in the study area, the boundaries of Pondoland Centre of Endemism and the boundaries of the Wild Coast National Park planning domain. Each is assessed according to the proportions of sensitive habitats that they would traverse. Figure 2: Proposed s between Mthatha and Port Shepstone showing vegetation sensitivity, boundaries of the Pondoland Centre of Endemism and the Wild Coast National Park planning domain.

15 Potential impact of The Gallagher would traverse approximately the same proportion of high sensitivity habitats as upgrading of the existing N2, and a marginally higher proportion of habitats of low sensitivity class (Table 5) and thus less distance of sensitive features. Both these s would affect lower proportions of high sensitivity habitats than the SANRAL preferred (Table 5). Relative to one another, the Gallagher alignment, the existing N2 alignment and the SANRAL preferred alignment therefore all potentially have a MEDIUM impact on the botanical receiving environment between Mthatha and Port Shepstone. Table 5: Lengths and proportions of alternative s in different sensitivity classes for ENTIRE DISTANCE from Mthatha to Port Shepstone. Route High Medium Low Rating Gallagher Existing N2 SANRAL preferred Total distance (Mthatha to Port Shepstone) (km) Portion in greenfields section (Lusikisiki to Mthamvuna River) (km) Total distance of sensitive features (km) Overall sensitivity score MEDIUM MEDIUM MEDIUM 3.2 Risk assessment of The Gallagher and the existing N2 are relatively similar in the proportions of sensitive features that could potentially be affected up to 1 km from the proposed road for the entire from Mthatha to Port Shepstone (Table 6), whereas the SANRAL preferred would affect a higher proportion of ecosystems of high sensitivity within the 1 km affected zone. Relative to one another, the potential risk to the botanical receiving environment between Mthatha and Port Shepstone is therefore rated as being MEDIUM for the Gallagher and the N2 upgrade, whereas it is rated MEDIUM-HIGH for the SANRAL preferred.

16 12 Table 6: Proportions of s in different sensitivity classes for ENTIRE DISTANCE from Mthatha to Port Shepstone for a including a 1 km potential affected zone on each side to demonstrate the potential effect of secondary impacts. Route High Medium Low Area (ha) Overall sensitivity score Rating Gallagher MEDIUM Upgrading existing N MEDIUM SANRAL preferred MEDIUM- HIGH

17 13 4. CONCLUSION The sensitivity assessment undertaken in this study provides an evaluation of the relative impact of the different proposed alignments. A qualitative summary of the sensitivity of the different s is given in Table 7 for the greenfields section and in Table 8 for the entire alignment from Mthatha to Port Shepstone. The rankings given in these tables is expressed in a relative form and is based on the proportion of each within medium to high sensitivity classes, as described in Section 1.2, above. 4.1 Summary of assessment within greenfields section A summary of sensitivity and risk to the botanical receiving environment within the greenfields section is presented in Table 7 using the comparative rankings given in the Methods section above (Section 1.2). With regard to the additional greenfields alignments between Lusikisiki and the Mthamvuna River the WESSA traverses less proportion of habitats with a high sensitivity compared to the SANRAL preferred and the Coastal Mzamba. The overall sensitivity rating for the WESSA is therefore MEDIUM, whereas the overall sensitivity rating for the SANRAL preferred and the Coastal Mzamba is MEDIUM-HIGH (Table 7). If potential secondary impacts from the proposed road are taken into account then the WESSA potentially affects less areas of sensitive habitat than the SANRAL preferred or the Coastal Mzamba. The overall rating of risk to the botanical receiving environment for the WESSA is therefore MEDIUM, whereas for the SANRAL preferred and the Coastal Mzamba it is MEDIUM-HIGH (Table 7). Table 7: Summary of sensitivity and rating of risk to receiving botanical environment for the s within the GREENFIELDS section (Lusikisiki to Port Edward. The sensitivity is based on a narrow corridor (100 m wide) and risk on a wide corridor (2 km wide). Route Sensitivity Risk WESSA Medium Medium Coastal Mzamba Medium-High Medium-High SANRAL preferred alignment Medium-High Medium-High

18 Summary of assessment for entire distance A qualitative summary of sensitivity and risk to the botanical receiving environment for the entire from Mthatha to Port Shepstone is presented in Table 8 using the comparative rankings given in the Methods section above (Section 1.2). For the from Mthatha to Port Shepstone, the Gallagher would have an impact on a similar proportion of habitats with a high sensitivity rating as upgrading the existing N2. The overall sensitivity of both these alignments is rated as MEDIUM (Table 8). Both these s affect a lower proportion of sensitive habitats than the SANRAL preferred alignment, which is, however, also given an overall sensitivity rating of MEDIUM (Table 8). If secondary impacts from the proposed road are taken into account, then the Gallagher and the N2 upgrade affect less area of sensitive habitats than the SANRAL preferred. The risk to the botanical receiving environment is rated as MEDIUM for these two alignments, whereas for the SANRAL preferred it is rated as MEDIUM-HIGH (Table 8). Table 8: Summary of sensitivity and rating of risk to receiving botanical environment for the ENTIRE from Mthatha to Port Shepstone. The sensitivity is based on a narrow corridor (100 m wide) and risk on a wide corridor (2 km wide). Route Sensitivity Risk Gallagher Medium Medium Upgrading existing N2 Medium Medium SANRAL preferred Medium Medium-High