2010

Sani Pass Road Upgrade: Baseline Biodiversity Assessment of the Aquatic Ecosystems of the Sani Pass Region, Southern Drakensberg, KwaZulu-Natal

GroundTruth Biomonitoring Services and Environmental Consultants January 2010

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Executive Summary

A joint venture between the Department of Transport (DoT) and the KwaZulu-Natal Department of Transport (KZN DoT) plans to upgrade the current Sani Pass road between the old Good Hope Trading Post and its summit at the Lesotho border. The proposed road upgrade plans to re-surface the existing gravel road to a hardened- surface, all-weather road. The road passes through the uKhahlamba Drakensberg Park World Heritage Site and thus has significant importance in terms of its conservation and biodiversity value. This report provides a description of the current ecological condition of the aquatic environment associated with the Sani Pass project, and reports on the results obtained from a wet season biological survey conducted during 2008/2009. The primary focus was on establishing a biodiversity baseline against which to reference the impacts that may occur as a result of construction and operation of the proposed road upgrade, as well as identifying the key impacts and issues which are likely to arise for the biodiversity assets of the area.

As part of the baseline investigations, various aquatic biomonitoring methods were used to determine the current condition of the aquatic environment within the Sani Pass area. These methods were used to give an indication of the current ecological status using indices based on water clarity, benthic diatoms and aquatic macroinvertebrates. Preliminary findings from the biomonitoring indicators showed that the aquatic ecosystems within the area are in a good condition. However, observations have shown that these systems have, for some time, been heavily impacted upon due to large quantities of sediments (largely generated from the current road condition), entering the aquatic ecosystems. This has serious long-term implications in terms of the future sustainability of these systems. Ultimately there is the risk of a loss in valuable ecological goods and services.

To highlight the importance of aquatic habitats within the context of the Sani Pass area, efforts were made to determine the species composition of important taxonomical groups, i.e. amphibians and ichthyofauna, and to establish whether there are any species that occur or potentially occur in the area which have a high ecological significance. This was achieved through desktop studies and field surveys. The results of this exercise highlighted that the Sani Pass, and its immediate surrounds, support a wide array of important species that are dependent on the ongoing protection of aquatic habitats. For the Mkhomazana River system, these include several important frog species, some protected based on their conservation status, as well as the Maloti Minnow whose Mkhomazana River population is apparently now extinct.

Beyond the extent of the Sani Pass project, and extending into Lesotho, is a small population of the endangered Maloti Minnow, along with high-altitude endemic frog species. This emphasises the importance of managing the broader area (beyond the immediate extent of the Sani Pass project) and its surroundings to ensure

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environmentally sensitive developments follow the Sani Pass road upgrade, and once accessibility to the summit of the pass and beyond into Lesotho is undoubtedly made easier.

To facilitate the protection of the aquatic environment, the various aquatic habitats occurring within the Sani Pass area were assessed through an identification and mapping process to determine the location of these systems in relation to the Sani Pass road. Particular emphasis was given to identify which of these areas are considered important and/or sensitive within the context of the proposed road upgrade. Within the complex network of aquatic systems occurring within the area, several rivers and wetlands were noted as being particularly important.

Key issues associated with the aquatic environments for this project include impacts related to:  sedimentation (from road runoff) – an existing problem in this system due to poor management and design of the current Sani Pass road,  chemical contamination,  modified hydrology,  habitat degradation and loss, and  loss of biodiversity  road crossings which may impact on wetlands within the project area. Of these, sedimentation was determined as the most significant issue with the potential to negatively impact on the aquatic ecosystems in the Sani Pass area. Driving the problems associated with sedimentation, modified hydrology was also considered to be an important impact that requires consideration during the proposed road upgrade. Chemical contamination, habitat degradation and loss, and loss of biodiversity were found to have a low impact rating. However, consideration of such issues throughout the construction and operation of the road is still important.

Recommendations are given for the mitigation of the aforementioned issues. Should these be incorporated into the management interventions of the road upgrade, impacts may be considerably reduced, and improvements over the current state of the aquatic ecosystems realised in the road upgrade. Therefore the upgrading of the Sani Pass road has potential to reduce current impacts, particularly from the outset of the operational phase, and allow for ecosystem restoration to take place. Most notable improvements relate to significant reductions to impacts associated with sedimentation and modified hydrology. However, the potential for cumulative impacts arising in the long term are probable given the increased development opportunities that will evolve through improved road access. Such issues, although beyond the scope of this project, would need to be considered in terms of their potential impacts on the aquatic environment.

The conclusions drawn from this report are a reflection of the results available during this stage of the project and cover a single season of fieldwork and sampling. The findings that will be documented in the final report will include both wet and dry season surveys and the recommendations adapted to reflect the findings from the final assessment. ii

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Table of Contents

Executive Summary ...... i Table of Contents ...... iii List of Tables and Figures ...... v Tables ...... v Figures ...... vi Abbreviations ...... vii Definitions ...... viii 1. Indemnity and Conditions Relating to this Report...... 1 2. Introduction ...... 2 2.1 Project description ...... 3 2.2 Legislation for the protection of the aquatic environment ...... 3 2.2.1 The National Environmental Management Act (NEMA) ...... 3 2.2.2 The National Water Act (NWA) ...... 4 2.3 Objectives ...... 4 3. Methods ...... 5 3.1 Study area ...... 5 3.2 Desktop studies ...... 6 3.2.1 Conservation status ...... 6 3.3 Appropriate aquatic biomonitoring indicators ...... 7 3.3.1 Water quality indicators...... 7 3.3.2 Benthic diatoms ...... 8 3.3.3 Aquatic macroinvertebrates ...... 8 3.4 Data analysis and interpretation of data ...... 9 3.5 Establishing aquatic biodiversity assets ...... 11 3.5.1 Herpetofauna – frogs ...... 11 3.5.2 Ichthyofauna – fish ...... 11 3.5.3 Aquatic ecosystems ...... 12 3.6 Impact assessment ...... 12 4. Results ...... 14 4.1 Survey of aquatic systems ...... 14 4.1.1 Water clarity ...... 14 4.1.2 Benthic diatoms ...... 14 4.1.3 Aquatic macroinvertebrates ...... 15 4.2 Aquatic biodiversity assets ...... 16 4.2.1 Frog diversity ...... 16 4.2.1.1 Red Data species ...... 16 4.2.1.2 Other notable species ...... 17 4.2.4 Frog habitat types and distribution ...... 20 4.3.3 Reptiles associated with aquatic environments ...... 20 4.3.2 Ichthyofauna – fish ...... 21 4.3.2.1 Historical fish records ...... 21 4.3.2.2 Current status of fish ...... 22 4.3.3 Representation of aquatic ecosystems ...... 23 4.3.3.1 Classification of aquatic systems ...... 23 4.3.3.2 Mapping of aquatic systems ...... 25 iii

Sani Aquatic Baseline Biodiversity Assessment 2010

5. Discussion ...... 32 5.1 Assets, constraints and opportunities ...... 32 5.1.1 Aquatic ecosystems ...... 32 5.1.2 Aquatic biodiversity ...... 32 5.2 Potential aquatic biodiversity issues...... 36 5.2.1 Issue: Degradation/loss of aquatic ecosystems ...... 36 5.2.1.1 Sedimentation ...... 36 5.2.1.2 Modified water chemistry ...... 38 5.2.1.3 Modified hydrology ...... 40 5.2.1.4 Physical destruction of habitat ...... 41 5.2.2 Issue: Loss of important species ...... 41 5.2.3 Issue: Cumulative impacts of the road upgrade ...... 42 5.3 Impact assessment ...... 43 5.3.1 Rating of impacts ...... 44 5.3.2 Environmental significance of the impacts ...... 44 5.4 Consideration of road alternatives ...... 43 5.5 Recommendations for mitigation of impacts ...... 47 6. Conclusion ...... 49 7. Acknowledgements ...... 50 8. References ...... 51 9. Appendices ...... 54 APPENDIX 1. Benthic diatom flora data ...... 55 APPENDIX 2. Macroinvertebrate data ...... 57 APPENDIX 3. Freshwater ecosystem localities ...... 58

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List of Tables and Figures

Tables

Table 1: Summary of aquatic biomonitoring sites sampled during the wet season (December 2008) (site co-ordinates in decimal degrees, WGS84)...... 5 Table 2: Aquatic macroinvertebrate SASS5 index and benthic diatom scores used to define river health class boundaries...... 10 Table 3: River Health Classes and their attendant Ecological and Management perspectives...... 11 Table 4: Ranking scales used for the different impact factors describing each impact on the aquatic environment ...... 13 Table 5: Determination of impact rating using the significance points calculated for each impact...... 13 Table 6: Water clarity measurements taken during the wet season biomonitoring survey (December 2008)...... 14 Table 7: Summary of results from the routine water clarity monitoring conducted on the Mkhomazana River at Site 04. Results are based on a total of 13 samples, and are differentiated according to whether rainfall had occurred...... 14 Table 8: Summarised benthic diatom indices and river health classification (based on Table 2) for sites monitored during the wet season survey (December 2008)...... 15 Table 9: Summary of aquatic macroinvertebrate health metrics (scores) established for the Mkhomazana River at site 03, near to the South African border, during December 2008. River health classification is determined and interpreted based on Table 2 and Table 3 respectively ...... 15 Table 10: List of frog species recorded from surrounding areas (May occur), recorded historically (Present), or recorded during the survey (Present – recorded during survey). Species whose taxonomic classification has recently been revised (Frost et al., 2006; van Dijk, 2008; Tarrant et al., In Press) have previous genus names shown in brackets...... 19 Table 11: Assets, constraints and opportunities for the Sani Pass area...... 33 Table 12: Rating of impacts (1 – low; 5 – high) associated with the proposed Sani Pass road upgrade during construction. Ratings accounting for mitigation are shown in parenthesis...... 44 Table 13: Rating of impacts associated with the proposed Sani Pass road upgrade during operation...... 44 Table 14: Environmental significance of the impacts relating to construction of the Sani Pass road with and without mitigation. Impact categories are assigned for each impact...... 45 Table 15: Environmental significance of the impacts relating to the Sani Pass road upgrade during operation with mitigation...... 45 Table 16: Environmental significance of the impacts relating to the current Sani Pass situation and the potential improvement that can be expected post construction (i.e. operational phase) assuming sufficient mitigation is implemented...... 46

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Figures

Figure 1: Spatial distribution of biomonitoring sites and river sections sampled during the biomonitoring survey with reference to the Sani Pass project study area ...... 6 Figure 2: Spatial distribution of sites where rivers (perennial and non-perennial) and wetlands intercept the Sani Pass road along the upper section...... 26 Figure 3: Spatial distribution of sites where rivers (perennial and non-perennial) and wetlands intercept the Sani Pass road along the middle section...... 26 Figure 4: Spatial distribution of sites where rivers (perennial and non-perennial) and wetlands intercept the Sani Pass road along the lower section...... 27 Figure 5: Spatial distribution of hillslope seepage wetland site 1 sites in relation to the Sani Pass...... 28 Figure 6: Spatial distribution of hillslope seepage wetland site 2 sites in relation to the Sani Pass...... 29 Figure 7: Spatial distribution of hillslope seepage wetland site 3 sites in relation to the Sani Pass...... 30

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Abbreviations

Abbreviation Explanation ASPT Average Score per Taxon DoT Department of Transport EIA Environmental Impact Assessment EMP Environmental Management Plan HGM Hydrogeomorphic units IUCN International Union for Conservation of Nature KZN DoT KwaZulu-Natal Department of Transport NAEBP National Aquatic Ecosystem Biomonitoring Programme NWA National Water Act NEMA National Environmental Management Act NEMBA National Environmental Management: Biodiversity Act NEMPA National Environmental Management: Protected Areas Act PTV Pollution Tolerant Valves SASS5 South African Scoring System version 5 SPI Specific Pollution sensitivity Index UDP WHS uKhahlamba Drakensberg Park World Heritage Site WRC Water Research Commission

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Definitions

Term Definition Amphibians The taxonomical group of animals that refers to frogs Average Score Per Taxon SASS index determined by dividing the SASS Score by the Number of Taxa (families) Benthic diatoms Microscopic algae found in almost all aquatic habitats that are useful indicators of ecological health Biomonitoring Refers to biological monitoring, a tool in assessing the condition of aquatic ecosystems based on biological data Herpetofauna The taxonomical group of animals that refers to all amphibians and reptiles Hydrocarbons Organic compounds composed only of carbon and hydrogen, such as fuels for vehicles Hydrogeomorphic units System used to classify wetlands based on their landform setting and dominant wetland characteristics Ichthyofauna The taxonomical group of animals that refers to fish Instream habitat Typically the areas restricted to the river channel Pollution tolerant valves Benthic diatoms that are tolerant to reasonable amounts of pollution Red List List of taxa from a specific taxonomical group which have been assessed according to their risk of extinction and/or conservation status Riparian habitat Includes both instream habitats and those vegetated areas along a river channel, which consist of plant species specific to riparian areas SASS Score SASS Scores are calculated by summing the „quality‟ scores specific to each taxon (family) for all taxa recorded Specific Pollution sensitivity Index Index used to define the ecological health of a water resource based on the abundance of diatom species and their respective indicator values and pollution sensitivities Stormflow runoff That water which is generated as a result of a rainfall event Suspended sediments Soil particulates that are suspended in a water column Taxa Refers to a number of organisms which are collectively referred to as a single group Water clarity Method of determining the amount of suspended sediments in a water body

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1. Indemnity and Conditions Relating to this Report

The findings, results, observations, conclusions and recommendations given in this report are based on the author‟s best scientific and professional knowledge as well as available information. The report is based on survey and assessment techniques which are limited by time and budgetary constraints relevant to the type and level of investigation undertaken and GroundTruth and its staff reserve the right to modify aspects of the report including the recommendations if and when new information may become available from ongoing research or further work in this field, or pertaining to this investigation.

Although GroundTruth exercises due care and diligence in rendering services and preparing documents, GroundTruth accepts no liability, and the client, by receiving this document, indemnifies GroundTruth and its directors, managers, agents and employees against all actions, claims, demands, losses, liabilities, costs, damages and expenses arising from or in connection with services rendered, directly or indirectly by GroundTruth and by the use of the information contained in this document.

This report must not be altered or added to without the prior written consent of the author. This also refers to electronic copies of this report which are supplied for the purposes of inclusion as part of other reports, including main reports. Similarly, any recommendations, statements or conclusions drawn from or based on this report must make reference to this report. If these form part of a main report relating to this investigation or report, this report must be included in its entirety as an appendix or separate section to the main report.

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2. Introduction

GroundTruth consulting was appointed by Arcus GIBB (Pty) Ltd to undertake a baseline assessment of the aquatic biodiversity resources around the Sani Pass area for their client, the KwaZulu-Natal (KZN) Department of Transport (DoT), with reference to the proposed Phase 2 road upgrade of the Sani Pass road (P318).

The aquatic biodiversity assessment was done in accordance with and supported the following regulations and regulatory procedures:  National Environmental Management Act (NEMA) (Act 107 of 1998); and the  National Water Act (NWA) (Act 36 of 1998).

DoT plans to continue with Phase 2 of the proposed upgrade to the Sani Pass road, which extends from the old Good Hope Trading Post to the summit of the Sani Pass at the Lesotho Border post. The road as a result bisects the uKhahlamba Drakensberg Park World Heritage Site (UDP WHS). The Phase 2 upgrade will involve a complete re-grading and resurfacing of the current gravel road to a hardened-surface, all-weather road. To achieve this, the following will be required:  Road widening;  Re-alignment of road sections;  New bridge crossings;  Stormwater control and attenuation systems;  Bank and slope stabilisation; and  Road servitude rehabilitation.

These features of the road upgrade, and the necessary modifications that they may have on the natural environment of the area, may impact negatively on the aquatic biodiversity assets of the Sani Pass area of the UDP WHS. As such the aquatic biodiversity assets of the area need to be determined as part of the baseline assessment serving the Environmental Impact Assessment (EIA) for the Sani Pass project and to ensure adequate measures are taken to limit potential impacts. At the same time there are also potential positive consequences of the project, principally:  An alternative means of livelihood for local inhabitants; alternative income may relieve pressure on the surrounding resource base and help to preserve biodiversity assets;  Establishing the biodiversity baseline for the study area will assist in a broader understanding of the ecology of this area as well as providing an inventory of biodiversity assets (e.g. aquatic fauna and flora).  Preservation of representative biodiversity elements and sustained environmental development through the proposed development strategy provided the prevention and mitigation principles relating to the road upgrade be correctly adhered to.  Likely improvements to the receiving aquatic environments through a properly designed, engineered and maintained road upgrade, as opposed to the apparently ad hoc approach to the road in its current state.

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2.1 Project description

The Sani Pass project involves an upgrade to the current road, which will involve a re- grading and re-surfacing of the Sani Pass road (P318) (Figure 1).

The following key points are relevant to this study:  The Mkhomazana River is the dominant river system that drains the Sani Pass area. Its source is located at the summit of the Sani Pass; however, the river receives a substantial amount of water from the large number of tributaries that characterise the Sani Pass area.  The Mkhomazana River and its tributaries are generally fast flowing, owing to their steep gradients. River sections tend to consist of a series of riffles and pools which are underlain by a bolder and bedrock substrate.  Beyond the Sani Pass area, the Mkhomazana River runs in an easterly direction before joining the larger, more northerly Mkomazi River. The Mkomazi River eventually enters the Indian Ocean.  The Mkhomazana river system is a significant water resource to the Mkomazi Catchment and thus supplies a valuable supply of water to the water management area extending between the Mvoti and Umzimkulu Rivers.  The aquatic biodiversity and water resources associated with the Mkhomazana river system may become affected by the road upgrade, both during the construction and operation phases.  The upgrading of the Sani Pass road is unlikely to result in a significant loss of aquatic biodiversity assets except under circumstances where re-alignment will replace areas of aquatic habitat.

2.2 Legislation for the protection of the aquatic environment

Within South Africa, there are several legal acts that govern the protection of aquatic systems and aquatic biodiversity. These statutes are discussed in more detail in the following sections with reference to the proposed Sani Pass road upgrade:

2.2.1 The National Environmental Management Act (NEMA) The National Environmental Management Act (NEMA) (Act 107 of 1998) was promulgated to ensure protection to the environment, which includes all aquatic environments. NEMA provides a legal framework that allows for sustainable development through the integration of environmental factors in decision making and good environmental management with all development activities. In order to achieve sustainable development in accordance with NEMA, a development activity must limit the impacts to the environment that otherwise result in ecosystem disturbance and loss of biodiversity.

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2.2.2 The National Water Act (NWA) The National Water Act (NWA) (Act 36 of 1998) provides the necessary legislation that regulates the management of the use and protection of water resources. The primary aim therefore is to ensure water resources are used, protected, developed, conserved, managed and controlled in a sustainable and equitable manner while promoting environmental values. According to the NWA the following sections from Chapter 3 (“Protection of Water Resources”) of the act apply:  Part 3: The Reserve – Protection of water resources is required in order to protect the Reserve, which includes both the basic human needs reserve and the ecological reserve, and refers to both quantity and quality of water. Both the human and ecological reserves require a certain amount of water, of a certain quality, in order to supply individuals with water for essential needs and to protect the aquatic ecosystems of the water resource.  Part 4: Pollution prevention – Water resources also require protection from pollution resulting from activities on land. Therefore, in accordance to Section 19 of the NWA, the person who owns, controls, occupies or uses the land in question is responsible for taking measures to prevent pollution of water resources.  Part 5: Emergency incidents – in the situation where an accident occurs where the spilling of a harmful substance enter into a water resource, the onus is on the person responsible to remedy the situation.

2.3 Objectives

The primary aim of this aquatic biodiversity study is to establish the condition of the aquatic ecosystems occurring within the study area, including, but not limited to, the length of the Mkhomazana River, its tributaries and associated wetland systems situated in relation to the Sani Pass road. In light of this aim, and with reference to the project description above, the following were defined as the key objectives for establishing the important aquatic biodiversity features associated with the Sani Pass project:  Establish the presence of important species of aquatic biodiversity within the area of interest based on existing and historical data sources.  Provide detailed descriptions of the baseline condition of the aquatic systems, accounting for effects of seasonality, which could be used in future to monitor construction performance and if necessary provide objective evidence to determine the impact of the road upgrade operation on these ecosystems.  Consider the possible effects of the proposed road upgrade on the aquatic resources in the area.  Identify sensitive areas that are prone to impacts anticipated both during and after construction.  Offer ecologically pertinent recommendations in terms of best practice and mitigation procedures that will reduce expected impacts on the aquatic environment due to the road upgrade. And finally  Assess the level of impacts using the relevant impact assessment methodology.

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3. Methods

3.1 Study area

The area defining the aquatic biodiversity study corresponds with that of Phase 2 of the proposed Sani Pass road upgrade, which in terms of aquatic systems, includes the catchment area of the Mkhomazana River situated above the Good Hope Trading Post (Figure 1). The area therefore falls within the UDP WHS and thus carries significant importance in terms of its global biodiversity status, recognition and value.

Several sampling sites were located within the study area with the placement of these sites determined according to accessibility and availability of suitable sampling habitat. These sites were assessed using appropriate aquatic biomonitoring techniques to determine the aquatic biodiversity that will then form an integral part of the baseline pre-development scenario for the Sani Pass project. The sites therefore provide prospects for both before and after surveys, and thus serve to monitor and control any possible impacts arising from future developments. Table 1 provides a description of the sites in terms of the aquatic biomonitoring survey, whilst Figure 1 shows how these sites are spatially distributed throughout the study area.

Table 1: Summary of aquatic biomonitoring sites sampled during the wet season (December 2008) (site co-ordinates in decimal degrees, WGS84).

Site Biodiversity surveys Site descriptions River Latitude Longitude number conducted

Upper Sani River site 1 Sani Fish/Diatoms/WQ -29.58130 29.28871

Source of the Mkhomazana 2 Mkhomazana Diatoms/WQ -29.58639 29.29123 River Mkhomazana River at the 3 Mkhomazana SASS/Fish/Diatoms/WQ -29.60265 29.34246 South African border Mkhomazana River at 4 Mkhomazana SASS/Fish/Diatoms/WQ -29.63476 29.42009 Mkhomazana Lodge

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Figure 1: Spatial distribution of biomonitoring sites and river sections sampled during the biomonitoring survey with reference to the Sani Pass project study area.

3.2 Desktop studies

Desktop studies were performed to determine regional information pertaining to biodiversity assets relating to the Sani Pass project. Within the context of aquatic biodiversity, these included amphibians and fish. For species recorded during the field assessments, as well as species expected to occur in the region based on desktop assessments, information relating to their national importance (i.e. conservation status) was obtained through searching relevant databases.

3.2.1 Conservation status The conservation status of species for all taxa groups was determined using the IUCN categories (IUCN, 2008). This system is designed to determine the relative risk of extinction, with the main purpose of the IUCN Red List to catalogue and highlight those taxa that are facing a higher risk of global extinction with those listed as Critically Endangered, Endangered and Vulnerable collectively considered as Threatened. The IUCN Red List also includes information on taxa that cannot be evaluated because of insufficient information (i.e.

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Data Deficient) as well as on taxa that are close to meeting the threatened thresholds (i.e. Near Threatened).

Where Red List data is not available for a particular species regarded as important in the context of this study, its conservation status was evaluated through the species‟ threat category (i.e. Critically Endangered, Endangered or Vulnerable) as determined by the IUCN. This process involves any of the following assessments:  Population reductions (declines measured over the longer of 10 years or 3 generations)  Geographic range using either the extent of occurrence or area of occupancy  Population size and decline for a small population  Population size for very small and restricted populations  Quantitative analysis

3.3 Appropriate aquatic biomonitoring indicators

It is appropriate that most of the key elements of the aquatic food chain be examined as possible points of potential impact from the road upgrade, but also to highlight the present situation and its corresponding impacts. Consequently the following aquatic trophic levels were examined in this project:  the base of the food chain, primary producers (in this study represented by benthic diatoms)  primary and secondary consumers (aquatic macroinvertebrates and to a lesser degree fish)

In order to gain an understanding of the possible water related impacts that affect the aquatic food chain it is important, firstly, to define the aquatic environment in terms of its physical properties.

3.3.1 Water quality indicators Given the nature of this particular project and its associated environmental risks and impacts, water clarity monitoring was incorporated into the baseline monitoring programme. Water clarity, as measured using a metre-long transparent tube, is an effective method for quantifying the amount of suspended sediments in a water column. Hence this approach is particularly useful for monitoring the sediments entering the Mkhomazana river system as a result of the current road situation. This method establishes the baseline water clarity condition. Sediment related impacts that may arise during the construction and operation phases may be compared against the established benchmark.

Water clarity measurements were taken from several sampling sites during the wet season biomonitoring survey (9th to 12th December 2008). These sites, as defined in Table 1, are shown spatially in Figure 1. Subsequent to the field survey, a routine water clarity monitoring programme was established for the Mkhomazana River at the site near Mkhomazana Lodge where measurements are taken on a weekly basis, as well as after any significant rainfall events. Data from the routine water clarity measurements will provide a

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key indication of the baseline suspended sediments characteristic of the current situation, which includes seasonal variations and responses to individual stormflow runoff events.

3.3.2 Benthic diatoms Diatoms have been shown to be reliable indicators of specific water quality problems such as organic pollution, eutrophication, acidification and metal pollution (Tilman et al., 1982; Rott, 1991; Dixit et al., 1992; Cattaneo et al., 2004), as well as for general water quality (AFNOR, 2000). Round (1993) lists why diatoms are useful tools for biomonitoring:  diatoms have a universal occurrence throughout all rivers;  field sampling is rapid and easy;  the cell cycle is rapid and they react quickly to perturbation;  diatoms are relatively insensitive to physical features in the environment (although sensitive to chemical water quality parameters);  cell counting by microscopic techniques is relatively rapid and accurate (although requires the unique skills of a diatom specialist);  cell numbers per unit area of substratum are enormous, making random counts excellent assessments of diatoms;  the ecological requirements of diatoms are in many cases better known than those of any other group of riverine organisms;  permanent records can be made from every sample;  diatoms do not have specific food requirements, specialised habitat niches, and are not governed to a major extent by stream flow.

Diatoms (as primary producers) are also a key element of the base of the aquatic food web and disruption to their “natural” functioning has the potential to cascade up the food chain to all other trophic levels - hence their importance at the fundamental level of assessment.

The sampling protocol for diatom collection is relatively straight-forward and in this study the collection, preparation and analysis methodologies of Taylor et al. (2007) were employed. In summary, this involves a random collection of five sub-samples, taken mainly from submerged aquatic medium (e.g. stones and vegetation). Diatoms were then scraped or brushed off these sub-samples, and combined into one sample, to represent the sampled site. Using this approach, several sites were sampled for benthic diatoms along the Mkhomazana River during the wet season (December 2008), as described in Table 1 with spatial representation in Figure 1.

3.3.3 Aquatic macroinvertebrates Although an assessment of aquatic invertebrates is not the perfect tool for aquatic biomonitoring, they still illustrate a number of very useful characteristics, with the result that they are extensively used in aquatic ecosystem assessments. Bonada, Rieradevall, Prat, and Resh (2006) neatly summarise their distinct advantages, which include:  their ubiquitous occurrence;  their huge species richness, which offers a spectrum of environmental responses;  their basic sedentary nature, which facilitates spatial analysis of pollution effects;

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 the propensity of certain species to enter the water column (i.e., drift), which may indicate the presence of a pollutant;  the long life cycles of some species, which can be used to trace pollution effects over longer periods;  their compatibility with inexpensive sampling equipment;  the well described taxonomy for genera and families;  the sensitivities of many common species, which have been established for different types of pollution; and  the suitability of many species for experimental studies of pollution effects.

The South African Scoring System, Version 5 (SASS5) of Dickens and Graham (2002) is a biotic index designed for assessing the condition of South African streams and rivers based on aquatic macroinvertebrate assemblages. The SASS5 approach is therefore suitable in order to determine the river health of the river systems within the Sani Pass area.

In terms of the SASS5 sampling protocol, a sampling site was located to allow sampling of the full spectrum of available biotopes (sampling habitats); namely stones (rocky riffle sections), marginal vegetation within the main stream, and sediments (gravel/sand/mud). This site was located on the Mkhomazana River near the South African border post (Table1).

3.4 Data analysis and interpretation of data

Data obtained during the aquatic biomonitoring survey were analysed using:  index scores specific to each biomonitoring technique, and  univariate summary statistics.

The benthic diatoms were interpreted according to the Specific Pollution sensitivity Index (SPI) (WRC, 2004), whilst the macroinvertebrates were interpreted by the classification of “health” classes (similar to the diatom index). In addition to SPI, the percentage of Pollution Tolerant Valves (PTV) was determined due to the usefulness of this parameter in indicating the presence of diatoms that are tolerant to reasonable amounts of pollution.

Depending on the occurrence of different aquatic taxa, which have different pollution tolerance ratings, each bio-indicator assessment provides an indication of the state of health of the river. For example, two different but complimentary measures (or indices) are obtained from each aquatic macroinvertebrate sample, viz., the SASS score and the average score per taxon (ASPT) (Dickens and Graham, 2002). The SASS score is most useful in interpreting the health of a site in polluted rivers, whilst the ASPT is most useful in cleaner rivers (Chutter, 1998). Generally the higher the index (e.g. SASS score, ASPT, or SPI) the better the health, or condition, of a river. Reference Sites for respective Ecoregions as well as other monitoring site data from within the GroundTruth database of monitored sites, and those data available from the University of the North West and the South African Diatom Collection, were used to establish the benchmark against which to measure the current “state” or “river health” of monitored sites. Based on actual data collected during this

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work, and available reference sites, respective indices were used to define the class boundaries (Table 2) (de La Rey et al., 2004; Taylor pers. comm., 2009).

Classification of ASPT values into their respective river health classes is based on data available from reference sites defined specifically for various ecoregions in South Africa; this is according to work done by Dallas (2007). Typically, the Drakensberg Mountains (and therefore the Sani Pass area) fall within the upper zone of Eastern Escarpment Mountains ecoregion. Hence, ASPT classes are defined with reference to this ecoregion (Table 2). The SPI classification typically has five classes, but, for the purposes of comparison with the SASS index, has been kept to the four indicated in Table 2. The ecological and management interpretations of these classes (modified from the South African National Aquatic Ecosystem Biomonitoring Programme NAEBP) are presented in Table 3.

Table 2: Aquatic macroinvertebrate SASS5 index and benthic diatom scores used to define river health class boundaries. River Health Macroinvertebrate SASS5 ASPT Benthic diatom Specific Pollution Class/ health condition class boundaries Sensitivity Index (SPI) health USEPA EPT condition class boundaries Index > Natural or 7.0 > 17 =

Good > 6.0 13 – 17

Fair > 5.6 9 – 13

< Poor or 5.6 < 9 =

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Table 3: River Health Classes and their attendant Ecological and Management perspectives. River Health Ecological perspective Management perspective Classes No or negligible modification of in- Protected rivers; relatively untouched Natural stream and riparian habitats and by human hands; no discharges or biota. impoundments allowed Ecosystems essentially in good state; Some human-related disturbance but Good biodiversity largely intact mostly of low impact potential

A few sensitive species may be lost; Zones of competing uses; Fair lower abundances of biological developmental pressures are populations may occur. dominant feature. Habitat diversity and availability have Often characterised by high human declined; mostly only tolerant species densities or extensive resource present; species present are often exploitation. Management intervention Poor & Bad diseased; population dynamics have is needed to improve river health – been disrupted (e.g. biota can no e.g. to restore flow patterns, river longer breed or alien species have habitats or water quality. invaded the ecosystem).

3.5 Establishing aquatic biodiversity assets

3.5.1 Herpetofauna – frogs Surveys were carried out to determine the species composition of frogs for the Sani Pass area, as well as to ascertain the habitats present that support various frog species. These site surveys took place on the 26th to 27th September 2008 and 9th to 12th December 2008. Frog species present were detected using various methods; these included sweepnet collection of tadpoles, nocturnal and diurnal audio surveys of calling males, and electrofishing. Frogs sampled were then identified to species level.

A review of available literature was conducted to supplement fieldwork findings; this was achieved primarily using Minter et al. (2004). For the purposes of this survey and given that frog distributions are incompletely known, historical species records were obtained for the quarter degree grid within which the study area is located (i.e. 2929CB), together with those records from adjacent grids.

From the basis of the field and desktop surveys, all rare and threatened species occurring or potentially occurring were identified.

3.5.2 Ichthyofauna – fish A detailed fish survey was conducted from the 9th to 12th December 2008 to assess the fish species composition within the Mkhomazana River system, although, the Photo 1: Electro-narcosis fishing 11

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primary objective of the survey was to determine the presence of the Maloti Minnow. Sampling of the Mkhomazana River was restricted to the length of Mkhomazana River, and its major tributaries, occurring within the extent of Phase 2 of the proposed Sani Pass road upgrade. Fish sampling was carried out using electro-narcosis via a portable electro-fishing apparatus (see Photograph 1). The procedures employed for electro-fishing were to move up and downstream and across the channel at the chosen area netting any fish that fall within the electric field of the apparatus. Efforts were made to ensure the sampling of a variety of available micro habitats, for example pools, riffles/runs, vegetated sections, rocky substrates, etc. A sein net was also utilised where sections of river were suitable for this technique (i.e. deep, slow flowing reaches). The sections of the Mkhomazana River sampled are illustrated in Figure 1. A small section of the Sani River situated in close proximity to the Sani Pass road at the Summit was also sampled as it is known to support a population of Maloti Minnows.

3.5.3 Aquatic ecosystems River and wetland systems situated in areas adjacent to the current Sani Pass road were identified, classified (according to their dominant characteristics), and mapped to determine the spatial distribution and extent of these sensitive systems in the context of the proposed road upgrade. Given the linear nature of the road, which as a result bisects areas containing aquatic habitats, the area that was investigated for the presence of aquatic ecosystems was restricted to a 25 meter buffer area on either side of the current Sani Pass road. Adopting this approach, the entire length of the proposed Phase 2 was surveyed. Although the main task was to map the presence of aquatic ecosystems in relation to the Sani Pass road, basic assessments were carried out for the more sensitive systems to briefly determine their importance and value to the Sani Pass area, as well as to highlight any issues that have arisen as a result of the current road, or which are likely to arise from the road upgrade. Observations were recorded aid the investigation of how these systems may be restored to a more natural state of functionality.

The aquatic ecosystem survey took place from 15th to 16th April 2008 ?? during which the entire length of Phase 2 was assessed.

3.6 Impact assessment

Impacts identified during the scoping and assessment phases of the aquatic biodiversity study were assessed using a ranking scale approach of different impact factors; these include probability of occurrence, duration of occurrence, extent, and magnitude of the impacts. The ranking scales used in this approach are described in Table 4.

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Table 4: Ranking scales used for the different impact factors describing each impact on the aquatic environment Probability Duration 1 – Very improbable (probably will not happen) 1 – Of a very short duration (0-1 years) 2 – Improbable (some possibility, but low 2 – Of a short duration (2-5 years) likelihood) 3 – Medium term (5-15 years) 3 – Probable (distinct possibility) 4 – Long term (> 15 years) 4 – Highly probable (most likely) 5 – Permanent 5 – Definite (impact will occur regardless of any prevention measures) Extent Magnitude 1 – Limited to the site 0 – Small and will have no effect on the 2 – Limited to the local area environment 3 – Limited to the region 2 – Minor and will not result in an impact on 4 – National scale processes 5 – International scale 4 – Low and will cause a slight impact on processes 6 – Moderate and will result in processes continuing but in a modified way 8 – High (processes are altered to the extent that they temporarily cease) 10 – Very high and result in complete destruction of patterns and permanent cessation of processes

The environmental significance of each of the potential impacts was then assessed by calculating significance points for each impact. This was done using the following formula: Significance Points = (Magnitude + Duration + Extent) x Probability where a maximum of 100 is possible. Potential environmental impacts were then determined on the basis of Table 5 below.

Table 5: Determination of impact rating using the significance points calculated for each impact. Significance points Impact rating < 30 Low 30 – 60 Moderate > 60 High

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4. Results

4.1 Survey of aquatic systems

4.1.1 Water clarity Water clarity was measured at the respective biomonitoring sites. These results are presented in Table 6 and Table 7 as captured during the wet season biomonitoring and routine water clarity programme respectively.

Table 6: Water clarity measurements taken during the wet season biomonitoring survey (December 2008).

Site Water clarity (cm) Sani River – Site 01 100 Mkhomazana River – Site 02 100 Mkhomazana River – Site 03 96

Table 7: Summary of results from the routine water clarity monitoring conducted on the Mkhomazana River at Site 04. Results are based on a total of 13 samples, and are differentiated according to whether rainfall had occurred. Water clarity (cm) Parameter Without rainfall With rainfall (n=8) (n=5) Average 80 23 Minimum 58 7 Maximum 92 49

Based on the water clarity results obtained for the Mkhomazana River, suspended sediments respond strongly to stormflow runoff due to the occurrence of rainfall. During periods of no or little rainfall, the water clarity of the Mkhomazana River is predominantly clear with clarity averaging around 80cm. However, following rainfall events the water clarity, on average, decreases to around 23cm and in more extreme circumstances may decrease to 7cm. Although it is a natural phenomenon for a river system to experience a decrease in water clarity in response to rainfall, it appears that the more extreme levels of suspended sediments are as a result of excessive surface runoff and erosion derived from the present road situation. This presents a concern in terms of the affects that high levels of sedimentation and siltation have on aquatic biodiversity.

4.1.2 Benthic diatoms Diatoms were sampled at two sites along the Mkhomazana River as well as from the Sani River (Table 1). The results taken during the wet season have been summarised following microscopic examination and analysis; these summary results are presented in Table 8. Interpretation of the diatom data is made based on Table 3.

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Table 8: Summarised benthic diatom indices and river health classification (based on Table 2) for sites monitored during the wet season survey (December 2008). Specific % Pollution No. of Pollution Tolerant River Health Site species Sensitivity Valves (% Classification Index (SPI) PTV)1 Sani River – Site 1 18 17.8 0.8 Natural Mkhomazana River – Site 10 19.6 0.8 Natural 2 Mkhomazana River – Site 21 14.9 0.0 Good 3 1 PTV is a measure of the proportion of sampled diatoms that are tolerant to reasonable amounts of pollution

A full list of all diatom species encountered at each site is presented in tables in Appendix 1.

As mentioned, the diatoms provide two important elements to the aquatic biomonitoring results, namely, they form part of the baseline for the biodiversity assessment but also form an integrated indictor of overall water quality or river health (based on Table 2). Results from the assessments indicate that there is no obvious degradation of the water quality/river health in the Mkhomazana and Sani river systems, despite signs of potentially harmful nutrient inputs at the Mkhomazana River source due to a damaged sewerage system at the Sani Top (see Photograph 13). Consequently, all sites were found to be in a “natural” condition except for Site 03, near the South African border, which was in a “good” condition.

4.1.3 Aquatic macroinvertebrates A single site on the Mkhomazana River (i.e. near the South African border) was sampled for aquatic macroinvertebrates during both the wet and dry season. In principle, and according to SASS5 methodology, only a single macroinvertebrate sampling site was required in order to assess the ecological health of the Mkhomazana River within the study area. Information on the macroinvertebrates from this site provides an indication of the overall catchment condition, i.e. impacts derived from upstream catchment areas are reflected by the SASS5 indices. Identification of the macroinvertebrate taxa was done to family level, as per the SASS5 method. Results of the macroinvertebrate family composition are summarised below in Table 9.

Table 9: Summary of aquatic macroinvertebrate health metrics (scores) established for the Mkhomazana River at site 03, near to the South African border, during December 2008. River health classification is determined and interpreted based on Table 2 and Table 3 respectively Health metrics (scores) Wet season (December 2008) Dry season (September 2009) SASS5 Score 148 144 Average Score per Taxon (ASPT) 6.43 7.20 Number of Families 23 20 SASS River Health Good Natural Classification

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Indications from the SASS5 assessment (comparing these results with Table 2) shows that the ecological condition of the Mkhomazana River is “good/natural” as reflected by the aquatic macroinvertebrates present, the families and their respective tolerances to water quality. This is congruent with the diatom results reported earlier for the site.

A list of the macroinvertebrate taxa collected during the SASS survey are shown in Appendix 2.

4.2 Aquatic biodiversity assets

4.2.1 Frog diversity At least fifteen species of frog have been recorded in the Sani Pass area, with a further five species potentially occurring based on literature sources of historical data (Minter et al., 2004). A list of these species is shown in Table 10. Eight species were recorded during the field surveys (September and December 2008) (Table 10). Two high-altitude endemics (i.e. Amietia dracomontana and A. umbraculata (formerly A. vertebralis)), known from the quarter of a degree grids database, were not detected during the survey and appear to be confined to Lesotho above the pass. Generally, species richness decreases with increasing elevation, with about a third of the species listed in Table 10 occurring above 2000 m.a.s.l.

4.2.1.1 Red Data species One Red Data species, the Plain Stream Frog Strongylopus wageri, is known to occur in the area, according to Minter et al. (2004), and was recorded during the field surveys. Two additional Red Data species (i.e. Long-toed Tree Frog Leptopelis xenodactylus and Natal Leaf-folding Frog Afrixalus spinifrons) have been recorded from areas adjacent to the Sani Pass area. There is no appropriate habitat for A. spinifrons and therefore it is not expected to occur in the Sani Pass area, however, there is one location where L. xenodactylus could occur. More detailed information pertaining to Red Data species occurring in the Sani Pass area is as follows:

Plain Stream Frog Strongylopus wageri Strongylopus wageri (see photograph 2) is endemic to South Africa, occurring primarily along the escarpment and foothills of the Drakensberg Mountains from southern KZN to Mont-aux- sources, with isolated populations in northern KZN and southern Mpumalanga (Bates, 2004b). It is found in forest and montane grassland where it is confined to clear, medium- to fast- flowing streams and their associated pools. S. wageri is listed as Near Photo 2: Plain Stream Frog Strongylopus wageri Threatened because of its small extent of occurrence, fragmented distribution and an existing and projected decline in the extent

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and quality of its habitat over a large portion of its distribution (Bates, 2004b). Habitat loss, as a result of afforestation alone, is estimated to have been more than 20% in the last 50 years. Other threats include chemical pollution associated with sylviculture, alien plant invasions and the introduction of trout into streams (Harrison et al., 2001).

S. wageri tadpoles were observed in streams above two road crossings (see Photograph 7) suggesting that S. wageri is likely to occur in several of the tributary streams which feed the Mkhomazana River. S. wageri is not expected to occur in the Mkhomazana River itself.

Long-toed Tree Frog Leptopelis xenodactylus L. xenodactylus has a very localised distribution, being endemic to an area extending from Weza in the south to Giants Castle in the north, and within this range it is known to occur in very few locations within an altitude range of 1000 to 1850 m.a.s.l. (Burger, 2004). The closest records for this species in the Sani Pass area are from the Underberg region. L. xenodactylus occurs in shallowly inundated wetlands within grassland. It is listed as Endangered, given its small area of occupancy, severely fragmented distribution and continuing decline in area of occupancy, extent and quality of habitat, and number of locations.

Within the study area, a single site appeared as being possibly suitable habitat for this species – a large grassy wetland (29°36′ 50′′ S; 29°22′ 30′′ E), which appears to be a unique feature for the Sani Pass region. Although not recorded here during the survey, L. xenodactylus is a cryptic species that may have been overlooked, and its presence cannot be ruled out.

4.2.1.2 Other notable species In addition to Red Data species, a number of other species that have been recorded from the area are considered notable, on the basis that they are habitat specialists, localised endemics and / or under threat in parts of their range:

Natal Ghost Frog Hadromophryne natalensis Hadromophryne natalensis is a South African endemic, occurring in the eastern escarpment mountains from Limpopo Province down to southern KZN. It has recently been placed in its own genus, separate from the Cape Ghost Frogs Heleophryne spp. (van Dijk, 2008). Hadromophryne is a habitat specialist, requiring clear, swift-flowing, rocky streams. The tadpole life stage lasts at least two breeding seasons, so the tadpoles are dependent on perennial stream flow. Although not currently Redlisted, H. Photo 3: Natal Ghost Frog Hadromophryne natalensis has suffered from loss of habitat, natalensis metamorph, collected from Mkhomazana River including the drying of perennial streams as

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a result of afforestation, which can eliminate entire breeding populations. It is also threatened through the introduction of alien fish, and general degradation of stream water quality as a result of surrounding land uses (Boycott, 2004).

Hadromophryne tadpoles, metamorphs and subadults were collected widely in the Mkhomazana River during the field surveys.

Maluti River Frog Amietia vertebralis Amietia vertebralis is a high-altitude endemic, with a very restricted range in Lesotho and adjoining South African Drakensberg. It has suffered from a very confused taxonomic history with recent research resulting in its movement from the genus Strongylopus to Ametia (Tarrant et al., In Press). Many of the museum specimens that were previously used to describe its distribution have recently been found to be incorrectly identified (Berkeljon, 2007; Tarrant et al., In Press). Currently, the southernmost confirmed records are from near Thabana Ntlenyana in Lesotho, north of Sani Pass (Dr M. Cunningham pers comm., 2009). Although it was not recorded in the Mkhomazana River, its presence in some of the tributaries cannot be ruled out. A. vertebralis is highly aquatic and is found in and nearby streams and associated pools with rocky and sandy substrates. Tadpole development is poorly known, but may take longer than a year (Dr M. Cunningham pers comm., 2009). Although not currently Redlisted, A. vertebralis has a highly localised distribution (more so than is indicated in current literature) and has been the subject of die-offs related to a fungal disease (Channing, 2004; Harvey, 2009) and may warrant conservation concern in future (Channing, 2004; Berkeljon, 2007).

Karoo Toad (Drakensberg population) Vandjikophrynus gariepensis nubicolus Vandijkophrynus g. nubicolus is currently treated as a subspecies of Karoo Toad, which occurs widely in southern South Africa. This montane toad is genetically distinct from V. g. gariepensis (Cunningham and Vences, 2006) and may represent a distinct species. It has a localised distribution, being confined to the high Drakensberg Mountains and occurring between Mont-aux-Sources and Sani Pass, extending to Naude‟s Nek in the south-west (Bates, 2004a). It occurs in grassland at altitudes of between 2000 and 3400 m.a.s.l. and utilises marshy areas and temporary pools for breeding.

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Table 10: List of frog species recorded from surrounding areas (May occur), recorded historically (Present), or recorded during the survey (Present – recorded during survey). Species whose taxonomic classification has recently been revised (Frost et al., 2006; van Dijk, 2008; Tarrant et al., In Press) have previous genus names shown in brackets.

Species Status in Sani Pass  Long-toed Tree Frog May occur Leptopelis xenodactylus  Karoo Toad (Drakensberg subspecies) Vandijkophrynus (Bufo) gariepensis nubicolus  Natal Moss Frog Anhydrophryne (Arthroleptella) hewitti  Mountain Caco Cacosternum parvum  Rattling Frog Present Semnodactylus wealii  Plaintive Rain Frog Breviceps verrucosus  Boettger‟s Caco Cacosternum boettgeri  Common Platanna Xenopus laevis  Cape River Frog Amietia (Afrana) fuscigula  Striped Grass Frog Ptychadena porosissima  Natal Sand Frog Tomopterna natalensis  Raucous Toad Present – recorded Amietophrynus (Bufo) rangeri during survey  Natal Ghost Frog Hadromophryne (Heleophryne) natalensis  Bubbling Kassina Kassina senegalensis  Bronze Caco Cacosternum nanum  Common River Frog Amietia (Afrana) angolensis  Maluti River Frog Amietia vertebralis (Strongylopus hymenopus)  Striped Stream Frog Strongylopus fasciatus  Clicking Stream Frog Strongylopus grayii  Plain Stream Frog Strongylopus wageri

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4.2.1.3 Frog habitat types and distribution Within the Sani Pass study area, all frog species (with the exception of Breviceps verrucosus) utilise aquatic habitats for breeding. Different species utilise different breeding habitats. For the purposes of this assessment, the aquatic habitats can be divided into three main types, each of which will support breeding populations of different species:

Mkhomazana River and lower tributaries These areas consist of large, strong-flowing rivers (see Photograph 4). Few (ca. 5) species of frog utilise this habitat type. Intensive electrofishing of the Mkhomazana River and its lower tributaries suggests that it primarily supports two species, Amietia angolensis and Hadromophryne natalensis, with A. angolensis confined to calmer sidewaters and H. natalensis occurring widely in rocky areas across the river profile.

Upper tributaries These are streams that are medium to fast-flowing and Photo 4: Mkhomazana River typically less than 1.5m wide, a number of which are crossed by the Sani Pass Road. The substrate consists of a combination of gravel and rocks. These support a greater species richness (ca. 9 spp) than the larger rivers. Notably, Strongylopus wageri only occurs in these habitats, as would Amietia vertebralis, if it is present.

Wetlands and seasonal / temporary Waterbodies Wetlands consisting of well vegetated areas of shallow inundation are relatively rare in the study area, primarily because of the scarcity of low gradient landscapes. There is one large grassy wetland (29°36′ 50′′ S; 29°22′ 30′′ E) within the study area (as shown in Figure 7) and a number of smaller wetland areas, some adjacent to the road. These wetland patches may support up to 12 of the species occurring, including Vandijkophrynus g. nubicolus and Leptopelis xenodactylus, if they are present.

4.2.2 Reptiles associated with aquatic environments One species of reptile that utilises aquatic habitats, the Cream-spotted Mountain Snake Montaspis gilvomaculata, is considered a sensitive species. This is a poorly known species, with only four individuals found so far, one of which is from Sani Pass (South African Reptile Red Data Book, In Prep.). It occurs from Sani Pass in the south up to Royal Natal National Park in the north, at altitudes of 1870 to 2870 m.a.s.l. M. gilvomaculata is found in grassland around wetlands and streams and limited knowledge of its ecology suggests that frogs form an important part of its diet (Bourquin, 1991; Branch et al., 1993). It is currently not Redlisted, as it was only discovered after the publication of the current evaluation (Branch, 1988), but will be listed as Data Deficient in the upcoming Red Data evaluation (South African Reptile Red Data Book, In Prep.).

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4.2.3 Ichthyofauna – fish The Mkhomazana River is considered significant from an icthyological perspective in that it is the river from which the Maloti Minnow (Pseudobarbus quathlambae) type specimens1 originated (Darwall et al., 2009), despite deficient fish surveys and/or the presence of trout suggesting that the Mkhomazana River has a reasonably poor diversity of fish species. The Maloti Minnow is classified as Endangered due to its severely fragmented populations with only a few known locations. They continue to experience a decline in their area of occupancy, the extent and/or quality of their habitat, and/or the number of mature individuals (Swartz, 2007). According to Skelton (2001), the Maloti Minnow has become threatened by the building of dams and roads, siltation of rivers and the introduction of alien fish species, most notably trout. Examples from rivers in Lesotho have attributed overgrazing and Photo 5: Maloti Minnow, collected from poor cultivation methods as additional the Sani River causes to heavy siltation of rivers and the subsequent pressure on this species.

4.2.3.1 Historical fish records The first Maloti Minnow specimens were collected in 1938 by trout fisherman, these were then sent to Grahamstown museum for identification. This resulted in them being discovered as a new, unidentified species; they were later named the Maloti Minnow (Pseudobarbus quathlambae) (Barnard, 1938). No further records of these minnows were made subsequent to this original collection from the Mkomozana River. It was only 32 years later that the Maloti Minnow was once again recorded, this time from the Tsoelikana River in the Sehlabathebe National Park, Lesotho. These specimens were collected during a rivers survey conducted by Messrs. A. Tedder, of Lesotho Fisheries, and T. Pike, a fisheries biologist from the then Natal Parks Board. This led to further investigations of the rivers in Lesotho which revealed the presence of these minnows in approximately 17 other rivers, all situated in the Maluti Mountains of Lesotho (i.e. the highland mountains of Lesotho). However, no further records of Maloti Minnows were reported from their “species type locality” (i.e. the Mkhomazana River) despite efforts from a very brief investigation carried out in 1991 on a small section (approximately 1km) of the Mkhomazana River, in the vicinity of the described locality where the original specimens were collected. This investigation was done by Messrs. T. Pike and R. Karssing (Natal Parks Board). According to best available knowledge, no thorough investigation of the presence of fish, particularly Maloti Minnows, has been carried out in the Mkhomazana River (Pike, 2008). Despite failing attempts to

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verify the type locality, and hence the existence of Maloti Minnows in the Mkhomazana River, correspondence from a Mr R.S.P. Vaughan in 1966 further supports evidence that these minnows resided in the Mkhomazana. The correspondence mentions that as members of the local River Conservancy, Mr Vaughan and several others collected minnows and sent samples to Pietermaritzburg for identification. He mentions that since the introduction of trout, the minnows have disappeared altogether. The Mkhomazana River nevertheless remains a well known trout angling river.

There is anecdotal evidence that the demise in the Maloti Minnow populations, in the Mkhomazana River on the South African side of the Drakensberg Mountains, may be attributed to the poor construction, alignment and maintenance of the Sani Pass road over the years. Arguably, the elevated sediment loads and habitat loss that have arisen as a result are probable candidates responsible for the loss of this fish species. However, Darwall et al. (2009) indicate that the introduction of trout to the Mkhomazana river system was the main causative factor resulting in the Mkhomazana population of the Maloti Minnow becoming extinct. It is particularly interesting that there are no other records of this species occurring in other river systems in South Africa. A possible explanation for the Maloti Minnow existing exclusively in the Mkhomazana River, and thus the only known population in South Africa, is due to headwater river capture followed by geographic separation resulting from landmass movements (Swartz pers.comm).

4.2.3.2 Current status of fish Given the limited attempts in the past to ascertain the presence of the Maloti Minnow within the Mkhomazana river system, a comprehensive fish survey was carried out to determine if they do occur in the Mkhomazana River. During this survey a significant portion of the Mkhomazana River that corresponds to Phase 2 of the proposed Sani Pass road upgrade was sampled (Figure 1). Despite efforts being concentrated along the sampled sections of river, no Maloti Photo 6: Brown Trout from the Minnows were detected. Only Brown Trout Mkhomazana River (Salmo trutta) were recorded within the Mkhomazana River, however, it was surprising to note that the abundance of Brown Trout was somewhat poor, regardless of the Mkhomazana being classed as a prime trout fishing river. Reasons for the limited numbers of Brown Trout may be attributed to the impacts associated with the sedimentation and siltation of the Mkhomazana River (i.e. loss of suitable breeding habitat, burial and suffocation of eggs and larvae, etc.). An additional factor affecting the distribution of trout in the Mkhomazana River is due to the presence of physical barriers; these include the waterfalls situated downstream of the Sani Pass Hotel and below the South African border. The latter appears to have excluded the movement of Brown Trout upstream as no trout were recorded above this natural barrier.

A healthy population of Maloti Minnows is located within the upper reaches of the Sani River, which is closely situated to the Sani Pass project area. Confirmation of the occurrence of

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the Maloti Minnow in this river system was made during the course of the fish survey. The presence of this population of Maloti Minnows emphasises the importance of controlling cumulative impacts that may arise due to the upgrading of the Sani Pass road and consequently the expansion of infrastructure and services. This will be discussed in more detail.

4.2.4 Representation of aquatic ecosystems

The Sani Pass area supports a complex network of aquatic habitats, mostly in the form of wetland and riverine ecosystems. These river and wetland habitats, referred collectively hereafter as aquatic ecosystems, support various species that depend on these aquatic habitats. They also provide a wide range of ecological services that are critical to the functioning of the earth‟s life support systems (Costanza et al., 1997). Aquatic ecosystems thus contribute directly and indirectly to human welfare.

Aquatic ecosystems are connected either directly or indirectly to each other essentially as a result of their position in the landscape. Aquatic ecosystems that occur throughout the Sani Pass area are generally linked directly to the Mkhomazana River via a network of rivers and streams. Depending on their level of connectivity, these systems form an integral component of the natural landscape by regulating the movement of water and other materials, which eventually enter into the Mkhomazana River. The degree of connectivity therefore determines how effectively natural process are conveyed between the various aquatic habitats. This in turn influences how effectively impacts are transferred between these systems.

4.2.4.1 Classification of aquatic systems As discussed previously, the characteristics of an aquatic ecosystem affect the manner in which ecological and hydrological processes take place, this in turn determines how effectively impacts will be conveyed through the natural landscape. Thus the type of aquatic ecosystem, and its natural ability to function, has a direct bearing on how impacts will be passed through the network of aquatic systems. As part of the identification and mapping of aquatic ecosystems situated in close proximity to the current Sani Pass road, all aquatic systems needed to be categorised. This was achieved through distinguishing rivers based on their characteristic riparian and instream habitats. Wetlands on the other hand were characterised according to the wetland hydrogeomorphic (HGM) units approach as used in the WET-Health technique (Macfarlane et al., 2007) as well as other wetland assessment methods. With the HGM approach, wetland units are defined based on geomorphic setting, water inputs into the wetland and the pattern of water flow through the wetland.

Given the topographical extremes of the Sani Pass area (i.e. a landscape dominated by steep slopes), aquatic ecosystems tend to be dominated largely by rivers and streams as opposed to wetlands. Where wetland systems are present, they were found to be predominantly hillslope seepage type systems. The following sections provide a description of the dominant types of aquatic systems that are characteristic to the Sani Pass area.

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Rivers and riparian habitats The Sani Pass area consists of a dense network of rivers and streams that drain the slopes of upland areas. Jointly, these systems contribute large amounts of streamflow to the Mkhomazana River, which forms the dominant river channel within the study area. The Mkhomazana River is therefore considered to be a significant freshwater resource for the Sani Pass area, but also forms a valuable water resource to downstream users beyond the Sani Pass area. Generally, the larger river systems that have reasonable catchment areas are perennial in nature with river flows sustained throughout the year. Conversely, smaller systems tend to be non- perennial in character.

All rivers in the area constitute flow arising from two dominant catchment responses, i.e. stormflow runoff and baseflow. Stormflow responses are confined mostly to the rainfall season, where flows are generated as a result of runoff at or near the surface of the catchment in response to rainfall events. Baseflows, on the other hand, constitute the flows that are supported by the recharge of groundwater; hence baseflows are significant in terms of sustaining flow throughout the dry seasons. Essentially, it is the latter that determines whether a river or stream is Photo 7: Tributary stream of the characterised as being perennial or non-perennial. Mkhomazana River

The rivers and streams of the Sani Pass area were classified according to their ability to sustain flows throughout the year. Although this is only possible through observation during the peak of the dry season, the distinction between perennial and non-perennial rivers was made based on the level of flow and relative size of the river.

Hillslope seepage wetlands Hillslope seepage wetlands occur on slopes where materials are typically transported by means of gravity, and where water inputs are received from diffuse sub-surface flow. These types of wetland systems are characteristic of the Drakensberg region and numerous hillslope seepages were located along the Sani Pass road, several of which are considered to be significant in the context of the Sani Pass road upgrade. Although some hillslope seepage wetlands showed characteristics of valley-bottom type wetlands, Photo 8: Typical hillslope seepage i.e. due to channelised water inputs, these characteristics are likely to be an artefact of the presence of the Sani Pass road and the unnatural hydrological responses that have developed as a result.

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In some instances the alteration of flow patterns, associated with the concentration or impoundment of flow by the Sani Pass road has resulted in the development of artificial wetland areas. Due to the artificial nature of these systems, they have not been included in the consideration of impacts on the natural aquatic ecosystems within the landscape.

4.2.4.2 Mapping of aquatic systems The longitudinal extent of the Sani Pass road bisects numerous river and wetland systems. Given the complexity of surface and sub-surface flow networks in the Sani Pass area, only those river systems that were found to contain water were mapped on the basis that they are considered significant in terms of receiving and transferring water quantity and quality impacts. Hillslope seepage wetlands, on the other hand, were mapped irrespective of the water flows into, through, and out of the wetland. Both river and wetland were identified based on the natural landscape terrain settings, as well as the dominant vegetation characteristics. The mapping of aquatic ecosystems through the interpretation of soil characteristics was not performed due to budget and time constraints. However the level of accuracy obtained in determining the extent of these features from landscape and vegetation characteristics alone, was deemed sufficiently accurate for the purposes of this study. More detailed hydromorphic soil investigations may be required to delineate aquatic habitats more accurately in situations where realignment will infringe on such habitats.

In developing an inventory of rivers and wetlands associated with the Sani Pass road, a total of 72 dominant aquatic ecosystems were identified and mapped during the field survey. Figures 2, 3, and 4 illustrate the spatial distribution of these systems relative to the Sani Pass road (i.e. upper, middle and lower sections). The location of each of these systems is given in Appendix 3. Differentiation is made according to the different types of aquatic systems. 12 perennial rivers intercept the Sani Pass road along the length of Phase 2, the type of crossings used at these sites ranges from crossings with no man-made interventions to concrete bridge structures. Generally culverts are used for the smaller, non-perennial rivers. Non-perennial rivers accounted for more than half of the aquatic ecosystems that were located during the survey. The remaining 18 sites were characterised as dominant hillslope seepage wetlands, three of which are considered significant in terms of their extent, position and risk susceptibility. The more significant hillslope wetlands were mapped in more detail and briefly assessed in the context of the current situation.

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Figure 2: Spatial distribution of sites where rivers (perennial and non-perennial) and wetlands intercept the Sani Pass road along the upper section.

Figure 3: Spatial distribution of sites where rivers (perennial and non-perennial) and wetlands intercept the Sani Pass road along the middle section.

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Figure 4: Spatial distribution of sites where rivers (perennial and non-perennial) and wetlands intercept the Sani Pass road along the lower section.

Hillslope seepage wetland: Site 1 This system, as shown by Figure 5, is approximately 0.5 ha in extent and typical of the hillslope seepage type wetlands whereby a sudden change in terrain setting has resulted in the interception of groundwater at or near the surface. Consequently, the more frequent wetting allows for the colonisation of wetland type plant species. For this site, these include Gunnera repandum, Cyperaceae species (sedges) and several species from the family Gramineae (grasses).

The dominant issue present at this wetland site is primarily the infestation by alien plants, which presents a particular problem in terms of excessive water up-take. Alien plants at this site include Acacia dealbata and Rubus cunefolius.

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Although this site has typical characteristics of a wetland, it appears that such conditions have become more pronounced due to a damming effect caused by the presence of the road, thus resulting in an artificial extension of wetland habitat in some areas.

Figure 5: Spatial distribution of hillslope seepage wetland site 1 sites in relation to the Sani Pass. Attached is a photo of the wetland.

Hillslope seepage wetland: Site 2 This fairly small wetland, as shown in Figure 6, is approximately 0.2 ha and is situated on the down-slope side of the Sani Pass road. As a result, the wetland receives high amounts of runoff, generated from the road, and sediments due to erosion of the road surface. Additionally, culverts concentrate runoff from up-slope areas into the wetland compounding the effects resulting from unnaturally high surface water inflow.

The vegetation within the wetland is similar to the previous site, dominated by grass species, sedges and Gunnera repandum.

This site has been heavily impacted upon by the current road as well as road maintenance activities. The following issues are highlighted as a result:

 Unnaturally high water inputs received directly from road surface runoff – increased quantities and intensity of surface runoff has resulted in degradation to the wetland, primarily due to excessive erosion, channel incision and consequently a rapidly retreating head-cut (see photograph 9). The advancement of the headcut through the system, is altering the hydrological conditions through the desiccation of wetland areas adjacent to the resulting erosion gully/channel. Several areas within and

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surrounding the wetland have deteriorated due to poor maintenance and management operations. For example, culverts have become blocked, sediments have been forced into the wetland from grading and surface wash, and concrete pipes have been dumped into the wetland (see photograph 9).  Localised areas that have been subjected to destructive activities and sedimentation have become exposed to alien plant encroachment. As a result a number of wattle seedlings (see photograph 9) have established themselves along with Rubus species.

Figure 6: Spatial distribution of hillslope seepage wetland site 2 sites in relation to the Sani Pass. Attached is a photo of the wetland.

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Photo 9: Impacts arising from the Sani Pass road that are affecting wetland Site 2

Hillslope seepage wetland: Site 3 This wetland system, as shown in Figure 7 is approximately 2 ha in extent and is situated above the Sani Pass road. Its position in relation to the road has allowed this system to remain fairly isolated from impacts generated from the current road. From an intrinsic perspective, this wetland is considered to be extremely valuable due to its brilliant display of Red-hot poker flowers, which occurs at certain times of the year.

Dominant plant species occurring within this wetland include Kniphofia linearifolia, Cyperacaea species, Gunnera repandum, and species of grasses.

Figure 7: Spatial distribution of hillslope seepage wetland site 3 sites in relation to the Sani Pass. Attached is a photo of the wetland.

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The biggest threat to this wetland relates to channel incision at the outlet points (Figure 7). Channel incisions have developed due to the lowered elevation of the wetland outlets where they intercept the road due to the culvert structures. This results in a change in gradient of wetland drainage lines which causes surface water to erode downwards; over time, this leads to the upstream advancement of the head-cut and the consequent impacts on the wetland habitat, as described previously. This issue will need to be addressed in the road upgrade.

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5. Discussion

The following discussion provides a summary of the ecological assets associated with the aquatic environment of the Sani Pass area, how such assets influence the proposed developments, as well as the environmental issues that threaten these ecological assets. An evaluation of the potential impacts associated with the road upgrade is presented along with recommendations as to how such impacts may be mitigated. 5.1 Assets, constraints and opportunities

Based on the current situation of the Sani Pass road and projected future upgrade to the road, various aquatic biodiversity assets have been identified. Consequently, the following biodiversity components are assessed according to their assets, constraints and opportunities; aquatic ecosystems and aquatic biodiversity. Table 11 provides a summary of these assessments.

5.1.1 Aquatic ecosystems The aquatic ecosystems situated within the Sani Pass area provide a key environmental template supporting the provision of key ecological goods and services, but also the presence of aquatic biota. These systesms, lumped broadly as rivers and wetlands, therefore present a number of key assets, constraints and opportunities relating to the Sani Pass project. Potential impacts on these aquatic systems are associated with;  modified flow regimes (seasonality, timing, flow pattern, duration and intensity),  modified water quality regimes (relating primarily to sediment movement), and to a lesser extent,  modified habitats due to re-alignment of the current road.

5.1.2 Aquatic biodiversity During the course of the desktop and field surveys, species associated with aquatic ecosystems were noted. Special reference was made to important biota from various taxonomical groups, these mainly include, amphibians, reptiles and fish. Herpetofauna (frogs and reptiles) constituted the most important species in terms of required protection. In terms of fish, no important species of fish were noted for the Mkhomazana system. Furthermore from an ecological perspective, the presence of alien fish species within a World Heritage site suggests that the current alien fish species are not an asset to the Sani Pass area.

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Table 11: Assets, constraints and opportunities for the Sani Pass area. Environmental assets / services Opportunities / advantages Constraints / threats Aquatic habitats Hillslope seepage wetlands occurring throughout the Given the value of wetlands to the natural and social Wetlands may be directly or indirectly threatened by the Sani Pass area are valuable in terms of the functions environment, the developments associated with the road upgrading of the Sani Pass road, particularly during the they offer, these include, but are not limited to, sustaining upgrade should take these features into account and construction phase. Threats are most likely to be surface water resources, particularly during low flows, attempt to minimise negative impacts upon them. The attributed to increased sedimentation caused from and purification of water. These systems also provide Sani Pass road upgrade has the potential to improve the excavated materials and exposure of bare surfaces. Not important habitat for numerous species of biodiversity, condition of these wetland systems, particularly the more limited to the construction phase, unnaturally high some of which are important from an ecological significant systems that have become degraded due to surface runoff will also be detrimental to these systems. perspective. impacts arising from the current road situation. This is Such threats will compromise the overall integrity of achievable through a detailed Environmental these hillslope seepage wetlands which may then result Management Plan (EMP) that adequately covers on a loss of valuable services. Additional water quality rehabilitation and restoration procedures. For example; impacts may become more problematic due to accidental  maintaining/improving wetland health using erosion spills (fuels, concrete, etc.), which will be more probable control structures (e.g. „plugs‟ such as gabion and during construction as opposed to operation of the Sani concrete structures) will assist in halting headcut Pass road once upgraded. Re-alignment of the current erosion in the wetlands thus installing more natural road should, as much as possible, avoid direct loss of hydrology and wetland functionality. wetland habitat.  reducing transmission of excessive sediment into wetland habitats, which causes a smothering of vegetation and demise in biodiversity assets. This is achievable using planted vegetation and/or sediment trap fences.  removing alien vegetation and revegetating bare/exposed ground with suitable plant species within and surrounding wetland habitat will improve their abilities to function more naturally, i.e. binding soil, controlling surface runoff, reducing erosion, and promoting sediment deposition. Instream habitats such as riffles and pools are The proposed road upgrade has the potential to The road upgrade has the potential to contribute important as they provide heterogenous substrate significantly reduce the impacts associated with additional surface runoff to surrounding river systems. conditions, creating a range of microhabitats for excessive amounts of sedimentation to the rivers and Thus it is crucial that flow control structures are designed specialist aquatic biota. For example certain streams in the Sani Pass region. This situation would according to best management practice allowing for the macroinvertebrates are specialised for fast-flowing riffle otherwise continue to threaten river ecosystems should proper dissipation of energy associated with unnatural habitat, others are adapted to sediment substrates. the current road situation continue to deteriorate to the flow rates and volumes.

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Environmental assets / services Opportunities / advantages Constraints / threats Variable habitats promote a healthy balance for cost of surrounding rivers and streams. biodiversity interactions.

Riparian vegetation occurring along the rivers and The occurrence of alien vegetation, particularly Black Riparian areas, where they coincide with the Sani Pass streams of the Sani Pass area are useful in that they Wattle (Acacia mearnsii), along the length of the road, may become degraded even further due to provide important services (e.g. filtering of sediments Mkhomazana River and its tributaries negates the overall impacting activities, particularly during the construction and other pollutants) for the protection of rivers and integrity of these areas. It will be important to eradicate phase. This may lead to further encroachment of alien surface water resources. alien plants that are a threat to the riparian areas. This vegetation into riparian areas, especially if areas of may be achieved through the implementation of an alien disturbance remain exposed for a period of time. Correct plant eradication and rehabilitation programme within the revegetation and repeated follow-ups will be required project‟s EMP that allows for the restoration of natural where riparian areas are disturbed due to construction riparian functionality. This should be confined to a activities. reasonable area on either side of the proposed road; a 30 metre distance on each side (i.e. a 60 metre corridor) is suggested in order to ensure sufficient buffering of impacts arising from the road during both construction and operation phases; hence restoration should be initiated to immediate effect so that these areas can become well established. Areas beyond this corridor should fall within the jurisdiction of EKZNW. Aquatic biodiversity Amphibians are located throughout the Sani Pass area, Restoration of aquatic habitats is possible in the long- The Sani Pass road upgrade project may to some some are considered important from a biodiversity term; reduced impacts (e.g. excessive sedimentation, degree compromise the population of these, and other, perspective, namely Plain Stream Frog (Near erosion, etc.) and improved overall habitat functionality frog species. Destructions/deterioration of suitable frog Threatened) and Long-toed Tree Frog (Endangered). will promote frog biodiversity in the Sani Pass area. habitat due to impacting activities associated with the Such benefits, however, are most likely to commence construction phase is the greatest concern. Road kills once construction has ended. are likely to be the dominant cause of impacts to frogs, this will be a permanent issue due to the continual movement of vehicles along the Sani Pass road. Reptiles, such as the Cream-spotted Mountain Snake, Restoration of aquatic habitats is possible in the long- Ongoing habitat degradation may impact negatively on are dependent on aquatic habitats. This species, which term; reduced impacts (e.g. excessive sedimentation, reptiles associated with aquatic systems, most significant is known from the Sani Pass area, is expected to be erosion, etc.) and improved overall habitat functionality will be impacts towards the Cream-spotted Mountain listed as Data Deficient in the forthcoming Red Data lists. will promote reptile biodiversity in the Sani Pass area. Snake of which very little is known. This is expected to be limited to the construction phase only, although road kills may become more of an issue during operation due to the attraction of reptiles to the road surfaces for

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Environmental assets / services Opportunities / advantages Constraints / threats thermoregulation. Fish The Mkhomazana River is known have historically There is a great amount of potential to re-introduce the Indirectly, the Sani Pass road development has the supported a population of Maloti Minnows Maloti Minnow back into the Mkhomazana River, from potential of having a negative impact on the Sani River (Psuedobarbus quathlambae). The Maloti Minnows where it was first discovered. This would be an population due to cumulative future effects resulting from have, since their discovery in the 1930‟s, become extinct enormous accomplishment towards the conservation of other developments that arise in response to improved from the Mkhomazana River and thus South Africa. this species particularly as it no longer exists in South access and greater development opportunities in the However, a population still occurs in the Sani River African river systems, although it should be noted that Sani Pass region, particularly the summit area in situated near to the summit of the Sani Pass. Given their this is not an obligation of DoT, but rather EKZNW. Re- Lesotho. Such impacts to this very important population conservation status (i.e. Endangered) the Maloti Minnow introduction of this level will be regarded highly by the of Maloti Minnows will need to be cautioned for future acts as a flagship species for the Sani Pass region. South African Institute of Aquatic Biodiversity due to the developments, although not the direct responsibility of significance of providing additional suitable habitat thus Phase 2 of the Sani Pass Project. extending its highly limited distribution range. The occurrence of the Maloti Minnow in the UDP WHS, and more specifically the Sani Pass area, will also bring additional conservation value and accreditation. Above all the additional protection of this endangered species will be extremely valuable towards ensuring the continued existence of this unique flagship species. The upgrade of the Sani Pass road has the potential to greatly improve the condition of the Mkhomazana River‟s instream habitat to the extent that conditions would be more suitable for Maloti Minnows. Given that hardening of the road would have a positive impact, DoT may wish to provide support in collaboration with EKZNW in terms of a re-introductory program. As part of the re-introduction programme, it will be important to remove trout from the section of the Mkhomazana River that will support the Maloti Minnow. Natural features previously mentioned as forming barriers to trout could facilitate this.

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5.2 Potential aquatic biodiversity issues

A number of key potential biodiversity issues are identified and associated with the current Sani Pass road and proposed road upgrade. Overall, such issues are likely to either improve, worsen or remain much the same over the course of the proposed road upgrade. The course of the proposed road upgrade will have varying effects on these issues, ranging from improvement, through to a potential worsening of the situation. These concerns are outlined in more detail in the following sections:

5.2.1 Issue: Degradation/loss of aquatic ecosystems Any modification and/or loss of aquatic habitat will result in a loss in ecosystem goods and services which otherwise would provide a vital function to the natural environment. These functions are also valuable to societal systems. In light of this, there are various ecological concerns that relate to the present and future situations, most notably the issues associated with excessive erosion of the road and transport of sediments into aquatic environments. Other water quality concerns, although less of a problem, but which may become more problematic in the short term, are associated with chemical pollution to aquatic ecosystems. In addition to water quality impacts, there are issues related to artificially increased water quantities that may also have a negative effect on the aquatic ecosystems.

5.2.1.1 Sedimentation Suspended sediments are a unique water quality problem, when compared to typical polluting chemicals, in that they occur naturally where certain amounts are essential to the ecological function of aquatic systems. For example, natural quantities of sediments help to replenish sediment bedloads and create valuable micro-habitats, such as pools and sand bars. However, in excessive amounts they may constitute a major ecosystem stressor.

Suspended sediments have two major avenues of effect in aquatic ecosystems; namely, direct effects on aquatic biota, and direct effects on physical habitat, which result in effects on biota. Jha (2003) notes that sediments may affect the habitat for macroinvertebrates and fish directly in the following ways:  behavioural effects, such as inability to see prey or feed normally;  physiological effects, such as gill clogging; and  effects due to sediment deposition, such as burial and suffocation of eggs and larvae, as well as the loss of available habitat

Additionally, excess sediments within aquatic ecosystems affect habitat structure through various ways, such as changes in refugia for biota (e.g., changes in macrophyte communities), increased fines and scouring in streams, aggradation and destabilization of stream channels, and in-filling of wetlands and other receiving waters. Larger sands and gravels can create other problems, for example they scour diatoms and bury invertebrates.

With specific reference to amphibians, increased sedimentation is known to have a negative effect on stream-living frogs through the loss of rocky habitat for egg-laying sites, shelter and sources of food (Welsh & Ollivier 1998); it may also hinder tadpole development (Gillespie 36

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2002). Investigations by Welsh & Ollivier (1998) found that amphibian densities were significantly lower in streams impacted by sediment compared to unimpacted streams. For the Sani Pass, frog species such as Hadromophryne natalensis and Strongylopus wageri are likely to continue to be negatively affected by high sediment loads to the rivers and streams of the Mkhomazana river system.

The severity of effect of suspended sediments is a function of many factors, which, in addition to sediment concentration, duration, particle size, and life history stage, may include temperature, physical and chemical characteristics of the particles, associated toxicants, acclimatization, other stressors, and interactions of these factors. These factors in turn have influential effects on the types of biota that can survive in an aquatic ecosystem.

All rivers and streams provide transport corridors for sediments. Hence within the context of the Sani Pass road and its present condition, sedimentation presents a serious problem where sediments are transported with surface runoff from the road and other unvegetated areas adjacent to the road. Additional sources of sedimentation are derived from physical disturbances by vehicles, primarily at river crossings. As a result, sediments enter (directly or indirectly) into the different aquatic systems, and depending on the amounts of sediments, this may have a serious impact on Photo 10: River crossing where sediments the available habitat and its functions. enter directly into a river system Photograph 10 illustrates the potential problem of sediments from road runoff entering directly into river systems based on the current situation. Photograph 11 shows the potential problem of sediments that become mobilised at river crossings due to vehicle disturbances.

Photo 11: Sediment plumes generated at river crossings

Similarly, excessive amounts of sediments are also a problem for other aquatic ecosystems, such as wetlands. Within the Sani Pass area, wetlands were observed to be receiving excessive amounts of sediments as a result of the present road situation. The degree of

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sedimentation to these systems depends largely on their position in relation to the road. As a result the overall integrity of these wetlands will continue to be lost under the current scenario.

Within the context of the road upgrade, sediment related impacts are expected to be a serious issue. However, this will be temporary problem and restricted to the construction phase when significant amounts of sediments are likely to enter into the aquatic environment given the nature of the development. Large-scale sedimentation to the rivers and wetlands would typically have a tremendous impact on the aquatic environment resulting in the loss of habitat functionality, integrity, and potentially a loss of aquatic biodiversity. With consideration of the present status of the road and the level sedimentation that is currently affecting the rivers and wetlands, the sediment related impacts during the construction phase will be minor in comparison. Although this will depend largely on the amount of time it takes to complete the construction phase.

Photo 12: Heavy sediment wash from road construction and maintenance resulting in excessive sedimentation to the aquatic environment

Despite the inevitable sediment related impacts associated with the construction phase, the road upgrade will have a long-term environmental benefit as a result of replacing the degraded gravel road with a hard resistant road surface layer. Thus overall the road upgrade will impact positively on the aquatic environment allowing for a gradual recovery of sedimentation dynamics.

5.2.1.2 Modified water chemistry Other pollutants, excluding harmful amounts of sediments, present an additional problem for the aquatic ecosystems of the Sani Pass area. Primarily, these may include chemical pollutants caused from accidental spills from vehicles (e.g. fuels, oils, accidents on the pass etc.) as well as pollutants associated with sewage discharges due to poorly

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designed/maintained sewage infrastructure. However, such impacts are considered to be less of a problem in comparison to the issues relating to sediment impacts. Furthermore, chemical pollutants are likely to only be a problem over relatively small, localised areas. In the case of contamination to the aquatic environment, changes in pH, conductivity (or total dissolved salts), and dissolved oxygen in the water may be experienced.

From the perspective of the current road situation, chemical spills are considered to be insignificant; however, cases of accidental spills from vehicles is likely to increase during the course of the construction phase due the intensive use of heavy constructions vehicles. Following to the completion of the road upgrade, vehicle derived chemicals may continue to increase due to the improved accessibility to the area. Furthermore, pollutants are likely to become more mobile compared to the present situation due to the more impervious nature of the proposed road surface as well as the fact that the proposed road will be designed to rapidly remove surface water. Consequently, there will be opportunity for contaminants, such as hydrocarbons from vehicles and machinery, to pollute aquatic habitats close to the road resulting in various ecological implications. Frogs, in particular, are known to be sensitive to pollutants (Blaustein et al. 2003) and experimental research suggests that petroleum can negatively affect tadpole survival (Mahaney 1994), so spillage of such substances could further impact negatively on local frog populations.

Secondary threats to the aquatic environment posed by the road upgrade are expected due to increased traffic and access to the areas, which will result in increased human pressure and further developments. Increasing human activities within the Sani Pass area will result in more pressure on the environment. The Sani Top Chalet at the top of the pass highlights this situation. It currently discharges its partially treated sewage effluent into the headwaters of the Mkomozana (see Photograph 13). However, in recent times, the septic tank system serving the Sani Top failed resulting in inadequately treated effluent spilling from a ruptured tank system. Although, attempts have since been made to rectify the problem and improve the septic tank system, the aquatic environment was exposed to water quality issues for some period. Water quality issues such as these are likely to increase with the anticipated increase of pressure from further developments to the area. Photo 13: Leaking sewage treatment facility As such aquatic ecosystems will continue to discharging untreated effluent experience similar problems.

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5.2.1.3 Modified hydrology Modifications of both surface and sub-surface (i.e. groundwater) flows are of concern due to implications these have for aquatic systems in terms of their natural hydrological flow regimes. The flow in rivers is driven by the natural hydrograph response to surface and sub- surface flows. Wetlands on the other hand tend to attenuate flows thus providing sufficient retention time for the regulation of flows. However, in the context of the current Sani Pass road, the issue of surface runoff generated from the road surface results in unnaturally high surface runoff contributions to rivers and wetlands. This is particularly problematic where runoff discharges directly into aquatic systems. The contribution of additional quantities of surface runoff over a much shorter period of time exacerbates the issues attributed to physical damage to aquatic ecosystems, i.e. increased erosion, sedimentation and damage to vegetation (see Photograph 14). However, the current Sani Pass road provides some degree of retention of surface runoff due to the reasonable amount of surface roughness provided by the uneven, rocky road surface.

Photo 14: Impacts to the aquatic environment associated with unnaturally high stormflow derived from the road

The construction/upgrading of the road with a non-permeable surface will result in further modification of the hydrological flow regimes of aquatic systems. An impervious road surface will generate additional stormwater runoff, with a more rapid response time. Although comparing the road upgrade with the present situation, where a certain amount of infiltration is possible/encouraged, it is expected that the increase in surface runoff will be slight in comparison. Furthermore, the road upgrade will include an efficient runoff and drainage system that adopts the principle of increasing surface roughness and infiltration thus reducing the impact of surface runoff. Coupled with a sufficient number of cross drains spaced at regular intervals that effectively creates a diffuse runoff system, the overall road design would greatly improve how surface runoff is controlled compared to the current road situation where no storm water interventions are in place. Ultimately, the flow regime of the receiving rivers and wetlands will be improved resulting in a more natural hydrological response. This will have a knock-on effect for other hydrologically driven impacts, such as erosion and sedimentation, habitat destruction and alteration, and transport of pollutants.

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5.2.1.4 Physical destruction of habitat Physical habitat destruction relates primarily to the construction phase of the road upgrade. Reasons as to why the proposed Phase 2 construction process may cause destruction and/or degradation of aquatic habitats include;  placing the road construction corridor through such habitats,  deposition of excavated materials into these features,  dumping of other construction related waste, and  movement and storage of vehicles, equipment and personnel within or adjacent to such areas.

Such impacts apply particularly to the aquatic systems that are closely associated with the road as discussed previously. Although, bearing in mind what is proposed in terms of the road construction corridor, the issue of physical disturbance to the aquatic environment may be somewhat limited. For example the proposed road alignment does not deviate considerably from the current road placement, hence encroachment of the proposed road alignment into sensitive aquatic environments is considered to be minor from a habitat loss point of view. However, there are sections that will be in close proximity to aquatic habitats, thus increasing the threat of construction related impacts, i.e. movement of construction vehicles, equipment, and personnel.

5.2.2 Issue: Loss of important species It is well known that certain species of biota have very specific habitat requirements which restrict the existence of such species and often populations become confined to suitable areas for their survival. In some cases such areas may be fairly isolated resulting in the species becoming classified as a rare occurrence. If their specific habitat is threatened further by degradation or the species are over exploited, then they can become endangered and possibly extinct. With relevance to this project, the Maloti Minnow is a case in point with only 6 small populations of this species known (Skelton, 2001).

The Sani Pass area is known to contain important biota, some of which rely on specific aquatic habitats for their existence. In light of the proposed road upgrade, such species face the biggest threats through disturbances to the environment leading to habitat degradation, as discussed earlier.

Frogs, in particular, were found to be particularly diverse and abundant throughout the Sani Pass area, certain species of which are notable in terms of their conservation status (e.g. Strongylopus wageriI: Red Data – Near Threatened). Frogs are sensitive to environmental disturbance, given, amongst other things, their biphasic (terrestrial and aquatic) lifestyles, permeable skins and varyingly specialised (particularly breeding) habitat requirements. Therefore it is important that these are considered to ensure habitat protection during the course of the road upgrade. This is necessary to avoid potential negative impacts on frogs, namely:  Destruction and/or degradation of habitats  Sedimentation of breeding and larval habitats  Contamination of aquatic habitats

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 Modified hydrological regimes of aquatic habitats  Isolation/fragmentation of populations  Mortality of individuals

The issue relating to the presence of the Maloti Minnow within the Mkhomazana river systems does not have any significant bearing in terms of Phase 2 of the road upgrade. This is based on the assumption that no Maloti Minnows were recorded within the Mkhomazana River during the fish surveys. Their existence, no doubt, would have had a significant effect on the Sani Pass project. It can only be assumed that the Maloti Minnow once existed within the Mkhomazana River, as determined by their type locality records, and that they have since been lost from this system. The obvious reason for this is strongly tied to the sediment impacts arising from the Sani Pass road and subsequent sedimentation and siltation to the rivers and streams. In support of this, it has been determined from various fish and river surveys that the Maloti Minnows do not occur in rivers which contain moderate to heavy silt loads (Pike, 2008). This is because excessive deposits of sediment on the substrate of rivers would impact negatively on Maloti Minnows populations, either by:  suffocating fish eggs, or  eliminating aquatic insects and therefore the food source of the minnows.

Other possible explanations for the absence of Maloti Minnows within the Mkhomazana river system relate to the following:  The introduction/spread of trout may have resulted in the exclusion of the Maloti Minnow.  The actual location of the type specimens was recorded incorrectly; they may have been collected within a nearby river system (e.g. Sani River in Lesotho).  The fisherman that collected the type specimens may have done so from within Lesotho, but for fear of being accused of fishing illegally in Lesotho, they indicated the Mkhomazana River as the type locality.

5.2.3 Issue: Cumulative impacts of the road upgrade Cumulative impacts relate to the principal that through improving the level of accessibility to Lesotho, via the upgraded Sani Pass, development opportunities will open up in response to economical potential, resulting in an expansion of developed areas (e.g. hotels, restaurants, etc.). Such developments will result in additional pressure on the local environment. This creates a significant amount of concern for the aquatic ecosystems located on the Lesotho side of the Sani Pass. These areas are considered very important from the Photo 15: Maluti River Frog (Amietia vertebralis) perspective of protecting biodiversity

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assets, due to the presence of important aquatic species. Such species include the Maloti Minnow (Red Data – Endangered), which occurs within the Sani River in Lesotho. This area is also known to support a frog species, the Maluti River Frog Amietia vertebralis (Photograph 15), which is endemic to the area.

In terms of the potential long-term developments of the Sani Pass summit areas, it is crucial that consideration is given to these sensitive areas to ensure the protection of important biota, such as the Maloti Minnows and Maluti River Frogs.

5.3 Consideration of road alternatives

The six alternatives2, as described in the scoping report for the Sani Pass Phase 2 road upgrade (Arcus Gibb, 2008), were investigated from an aquatic biodiversity perspective. Bearing in mind the impacts arising from the current road situation (i.e. continuous erosion and sedimentation issues), the obvious preference is for Alternatives 4, 5 and 6 in favour of their potential for reducing the amount of sediment loads entering into the rivers and wetlands of the Sani Pass area. The first three options, especially Alternatives 1 and 2, are considered as having the least overall benefit with long-term negative consequences. Alternative 5, with proper planning and development, will provide the greatest ecological benefit to the aquatic environment provided that hydrological impacts due to excessive stormwater runoff arising from the hardened road surfaces are controlled using best practice.

5.4 Impact assessment

The most likely impacts associated with the proposed road upgrade have been identified and discussed accordingly. The following environmental issues are assessed in order to ascertain the occurrence (probability and duration) and severity (extent and magnitude) of related impacts as part of the impact assessment:  Sedimentation of rivers and wetlands  Modified water chemistry  Modified hydrology

2 Alternative 1 – No upgrade. Alternative 2 – Re-gravel, minor drainage improvements and maintain. Alternative 3 – Improve geometrics, upgrade drainage, retain splash-throughs, construct retaining walls and re-gravel. Alternative 4 – Improve geometrics, upgrade drainage, construct bridges and retaining walls, harden surface up to km 25, gravel to km 33. Alternative 5 – Improve geometrics, upgrade drainage, construct bridges and retaining walls, harden surface from km 14 to km 33. Alternative 6 – Improve geometrics, upgrade drainage, construct bridges and retaining walls, harden surface from km 14 to km 31 and tunnel (3km). 43

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 Degradation/loss of aquatic habitat  Loss of biodiversity

5.4.1 Rating of impacts Each impact is ranked according to their probability of occurrence, duration of occurrence, magnitude, and extent. Impacts ratings, however, have been determined on the basis of Alternative 5.

The impact ratings shown in Table 12 are associated with the construction phase of the road upgrade; the difference between implementing and neglecting mitigation is made. Table 13 provides a summary of ratings that are expected during the operation phase.

Table 12: Rating of impacts (1 – low; 5 – high) associated with the proposed Sani Pass road upgrade during construction. Ratings accounting for mitigation are shown in parenthesis. Impact rating Impact Water factor Sedimentation Hydrology Habitat Biodiversity chemistry Impact occurrence Probability 5 (4) 3 (3) 4 (4) 3 (2) 2 (2) Duration 2 (2) 2 (2) 2 (2) 2 (2) 2 (2) Impact severity Magnitude 8 (4) 4 (2) 6 (4) 6 (6) 4 (4) Scale/extent 3 (3) 2 (2) 3 (3) 1 (1) 1 (1)

Table 13: Rating of impacts associated with the proposed Sani Pass road upgrade during operation. Impact rating Impact Water factor Sedimentation Hydrology Habitat Biodiversity chemistry Impact occurrence Probability 2 2 3 2 2 Duration 5 5 5 5 5 Impact severity Magnitude 4 2 2 2 4 Scale/extent 2 2 3 1 1

5.4.2 Environmental significance of the impacts Impact ratings defined in Table 12 and 13 above were used to determine the significance that each impact has towards the environment both during construction and operation. The significance points and resulting impact category that were determined from the impact ratings are shown in Table 14 and 15. Probable benefits from incorporating a sufficient amount of mitigation are taken into consideration, particularly for during the construction period, and comparative significance points determined as a result. The assessment of impact significance during operation does include provision for proper mitigation (Table 15).

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Table 14: Environmental significance of the impacts relating to construction of the Sani Pass road with and without mitigation. Impact categories are assigned for each impact. Significance points (Impact category) Environmental impact Without mitigation With mitigation Sedimentation 65 (High) 36 (Moderate) Modified water chemistry 24 (Low) 18 (Low) Modified hydrology 44 (Moderate) 36 (Moderate) Habitat degradation/loss 27 (Low) 18 (Low) Loss of biodiversity 14 (Low) 14 (Low)

Table 15: Environmental significance of the impacts relating to the Sani Pass road upgrade during operation with mitigation. Environmental impact Significance points Impact category Sedimentation 22 Low Modified water chemistry 18 Low Modified hydrology 30 Low Habitat degradation/loss 16 Low Loss of biodiversity 20 Low

Based on the quantification of impacts, it is clear that sedimentation of the aquatic ecosystems is at present posing the serious detrimental threat to the biodiversity assets of the Sani Pass area; the significance of this impact is rated as being “high” (Table 16). This issue is expected to remain a problem during the time of construction with some improvement possible through the implementation of appropriate mitigation measures (Table 15). Nonetheless, the potential severity of these impacts should be avoided during construction, irrespective of the fact that the current road condition is having detrimental effects on the aquatic environment. Implementing mitigation during construction will reduce sediment related impacts, particularly in proximity to sensitive habitats. However, it is expected that sediment impacts will persist, despite efforts to prevent such issues. Therefore, with mitigation measures in place, it is estimated that “moderate” impacts will occur due to sedimentation issues arising during construction (Table 14). As already noted, the excessive sediment loading to the aquatic environment will be limited to the construction period (c.f. Section 5.2.1.1). A significant reduction in erosion and sediment transport from the road servitude is expected for the operation phase thereafter. This will have a considerable positive impact to the aquatic ecosystems in the area; a great contrast to the current situation. As a result the overall significance of sedimentation impacts for the operation phase is considered to be “low” and thus is a massive improvement form to the current scenario.

Modified hydrology is expected to persist with the construction and operational phases of the road upgrade. The effect of replacing the current hardened gravel surface with an impervious surface will result in an increase in surface runoff from the actual road surface; the extent of which will be increased due to increasing the width of the road. However, the road upgrade designs are based on advanced techniques for managing and dispersing surface runoff such that surface runoff from the road will be captured by a side drain system that can accommodate the roads design storm flow volumes. The drain system is also designed to reduce the rate of surface runoff through increase surface roughness and 45

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encourages infiltration through a filter section. The stormwater runoff will then be dispersed evenly from the road servitude and into the surrounding environment. Consideration of these aspects of stormwater management during the operation phase has a positive effect on the impact assessment as reflected in Table 15. The impact category for hydrological impacts is likely to be “low” due to expected improvements to the hydrological regime from the current scenario.

Impacts associated with modified water chemistry, habitat degradation and loss, and loss of biodiversity are regarded as being minor in the context of the road upgrade, particularly if processes such as concrete processing are conducted offsite. Whether or not mitigation measures are in place, impacts on the water chemistry, habitats, and biodiversity of the aquatic environment are expected to be “low”.

In comparison to the current situation, it is expected that the road upgrade will result in either positive or negative impacts on the aquatic environment depending on the type of impact. Table 16 summarises the significance of each of the aforementioned impacts with reference to the current situation of the Sani Pass road indicating the possible benefit or detriment to aquatic ecosystem functioning.

Table 16: Environmental significance of the impacts relating to the current Sani Pass situation and the potential improvement that can be expected post construction (i.e. operational phase) assuming sufficient mitigation is implemented. Percent Environmental impact Significance points improvement Sedimentation 80 (High) 73 Modified water chemistry 18 (Low) 0 Modified hydrology 44 (Moderate) 32 Habitat degradation/loss 22 (Low) 27 Loss of biodiversity 18 (Low) - 10

Noteworthy potential benefits to the aquatic environment are favourable, particularly in terms of sedimentation and modified hydrology of the rivers and wetlands, which have the greatest potential improvement from the current road situation due to expected significant reductions in surface runoff and soil erosion to the environment. The primary contributing factors to such improvements is a combination of constructing the road with a hard, resistant surface layer with a innovative drainage system capable of controlling stormflow runoff and dissipating the water in an Habitat degradation and loss is also expected to improve, mainly as a response to the reduction in soil erosion, but other reasons include benefits associated with habitat rehabilitation and alien plant eradication. However negative impacts are expected to occur in response to the road upgrade even with mitigation and best intensions to avoid impacts, for example loss of biodiversity. Loss of biodiversity is expected to increase as a function of the greater vehicle traffic that is anticipated. Although these impacts are expected to increase in relation to the current situation, the relative proportion of the increase is regarded as being relatively low. Overall, the potential positive impacts are considered to outweigh the negative ones and will thus be an overall benefit to the aquatic environment.

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5.5 Recommendations for mitigation of impacts

The following recommendations are made in support of ensuring the protection of river and wetland systems in the Sani Pass area:  All river and wetland areas identified and mapped during the assessment of aquatic ecosystems must be treated as sensitive and important areas, particularly those considered to be more significant systems. The more significant systems include all perennial river systems and the three dominant hillslope seepage wetlands (see Appendix 3 for site details).  Construction within or adjacent to river and significant wetlands must be minimised as far as possible. Where avoidance is not possible, necessary functionality assessments need to be undertaken to assess the risks and opportunities for the site.  Appropriate measures must be put in place to minimise erosion and the amount of sediment entering rivers and wetlands, particularly during the construction phase when the risk of such impacts will be high. Risks of erosion will become more problematic during the rainfall season.  It is important that the good vegetated buffer areas surrounding aquatic systems are maintained. These areas will help to absorb surface stormwater runoff thus allowing sediments to settle prior to reaching aquatic systems as well as provide additional filtering for other pollutants.  No dumping of excavated material and no storage of equipment and materials must be allowed within, and in close proximity to river and wetland areas.  The time periods during which bare soil surfaces remain exposed to the elements needs to be limited. Immediate efforts should be put in to action to revegetate such areas as soon as possible.  During both construction and operation, it is important that any accidental spills of fuels, construction materials, chemicals, effluents or other harmful substances are reported and acted upon immediately. Effective remediation and cleanup strategies and procedures need to be implemented.  Construction camps, equipment storage sites and ablution facilities serving the construction phase should be sited a reasonable distance away from aquatic systems. These areas need to be cordoned off and maintained throughout the development time period. Suitable buffer distances would need to be informed following a more detailed site assessment for each individual situation. Alternatively, suitable buffers may be used based on a wetland buffers approach currently being developed for Ezemvelo KZN Wildlife. Buffers specific to sensitive aquatic environments will be detailed in the EMP for the project.  Where aquatic ecosystems are impacted by construction activities, necessary action needs to be taken to fully rehabilitate the sites.  Sensitive aquatic systems that have been subjected to impacts arising from the current road situation should be rehabilitated to reduce ongoing deterioration to these systems. Observed sites of head-cut erosion occurring within wetlands needs attention. Incised channels need to be plugged and rehabilitated to prevent further head-cutting and to restore the overall integrity of these systems.  Activity associated with the road upgrade, such as soil and vegetation disturbance provides opportunity for the further spread of alien invasive plants. A comprehensive 47

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alien plant eradication and rehabilitation programme needs to be implemented to remove alien plant infestations that are present in and around aquatic systems within the road buffer.  An appropriate stormwater management plan must be designed and implemented during the operation phase, to control significant changes in hydrology to receiving aquatic systems.  Speed limits and speed bumps should be installed in an attempt to limit traffic-related mortality of animals

Best practices for the mitigation of negative impacts, tailored specifically to the site and the associated sensitive environments, should be detailed in the Environmental Management Plan for the road upgrade.

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6. Conclusion

The conclusions drawn from this report are a reflection of the results available at the time of writing. Hence the inclusion of dry season results will only be possible following the dry season survey. However, it is not anticipated that outcomes from the dry season survey will significantly alter the conclusions drawn thus far.

The objective of this report was to determine the current state of the biodiversity assets within the study area of the proposed Sani Pass Phase 2 road upgrade. The assessments that were carried out were done in accordance to the relevant legislation with regards to managing the environment. Subsequently, attempts were made to assess the level of potential impacts that are possible as a result of the road upgrade and to provide suggestions for necessary mitigation measures against such impacts.

According to the biomonitoring indicators, the aquatic ecosystems within the Sani Pass area were found to be in a reasonable ecological condition, despite signs of degradation. However, more localised impacts were obvious throughout the area. Possibly the biggest threat to the aquatic environment is attributed to the high sediment loads that are received as a result of the current road situation and its continual degradation.

If the recommendations highlighted above are followed, and if appropriate planning and monitoring systems are put in place, it is likely that the project will have limited impacts within the project area. If anything, negative impacts may be reasonably short-lived, and restricted to the construction phase. However, the long-term benefits from upgrading the Sani Pass road are favourable from the perspective that aquatic ecosystems in the Sani Pass area may be restored to an improved state of ecological integrity. As such local aquatic biodiversity assets will be adequately conserved, which is beneficial in that it adds value to the UDP WHS. This is provided that all future developments in the area (including the upgrade of the Sani Pass road) are ecologically sound, limiting direct and indirect impacts to the aquatic environment.

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7. Acknowledgements

The following specialists are acknowledged for invaluable input within their field of expertise;

James Harvey – Herpetofauna Tom Pike – Icthyofauna

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8. References

In Prep. South African Reptile Red Data Book. AFNOR 2000. Détermination de l‟Indice Biologique Diatomées (IBD). In (Ed) Norme Française N.F., Association Française de Normalisation. T 90-354. 63. Barnard, K.H. 1938. Description of a new species of fresh-water fish from Natal. Ann. Natal Mus. 8: 525-528. Bates, M.F. 2004a. Bufo gariepensis. In: Minter, L.R., Burger, M., Harrison, J.A., Braack, H.H., Bishop, P.J., and Kloefder, D.E., Atlas and Red Data Book of the Frogs of South Africa, Lesotho and Swaziland. 9SI/MAB SERIES Smithsonian Institute, Washington, U.S.A. Bates, M.F. 2004b. Strongylopus wageri. In: Minter, L.R., Burger, M., Harrison, J.A., Braack, H.H., Bishop, P.J., and Kloefder, D.E., Atlas and Red Data Book of the Frogs of South Africa, Lesotho and Swaziland. 9SI/MAB SERIES Smithsonian Institute, Washington, U.S.A. Berkeljon, J.A. 2007. Systematic Review of Amietia vertebralis (Hewitt, 1927) and Strongylopus hymenopus (Boulenger, 1920) (Anura: Pyxicephalidae). University of the North-West, Potchefstroom. Unpublished PhD Thesis Bonada, N., Rieradevall, M., Prat, N. and Resh, V.H. 2006. Benthic macroinvertebrate assemblages and macrohabitat connectivity in Mediterranean-climate streams of northern California. Journal of the North American Benthological Society 25: 32–43. Bourquin, O. 1991. A New Genus and Species of Snake from the Natal Drakensberg, South Africa. . Annals of the Transvaal Museum 35 (12): 199-203. Boycott, R.C. 2004. Heleophryne natalensis. In: Minter, L.R., Burger, M., Harrison, J.A., Braack, H.H., Bishop, P.J., and Kloefder, D.E., Atlas and Red Data Book of the Frogs of South Africa, Lesotho and Swaziland. 9SI/MAB SERIES Smithsonian Institute, Washington, U.S.A. Branch, W.R. 1988. South African Red Data Book – Reptiles and Amphibians. In (Ed) Foundation for Research Development, South Africa. South African National Scientific Programmes, Report no. 151. Branch, W.R., Haagner, G.V. and Bourquin, O. 1993. Further Specimens of the Cream- spotted Snake Montaspis gilvomaculata from Natal. Lammergeyer 42: 50-52. Burger, M. 2004. Leptopelis xenodactylus. In: Minter, L.R., Burger, M., Harrison, J.A., Braack, H.H., Bishop, P.J., and Kloefder, D.E., Atlas and Red Data Book of the Frogs of South Africa, Lesotho and Swaziland. 9SI/MAB SERIES Smithsonian Institute, Washington, U.S.A. Cattaneo, A., Coullard, Y., Wunsam, S. and Courcelles, M. 2004. Diatom taxonomic and morphological changes as indicators of metal pollution and recovery in Lac Dufault (Québec, Canada). Journal of Paleolimnology 32: 163-175. Channing, A. 2004. Strongylopus hymenopus. In: Minter, L.R., Burger, M., Harrison, J.A., Braack, H.H., Bishop, P.J., and Kloefder, D.E., Atlas and Red Data Book of the Frogs of South Africa, Lesotho and Swaziland. 9SI/MAB SERIES Smithsonian Institute, Washington, U.S.A. Chutter, F.M. 1998. Research on the Rapid Biological Assessment of Water Quality Impacts in Streams and Rivers. In (Ed) Water Research Commission, Pretoria. WRC Report no. 422/1/98. Costanza, R., d'Arge, R., de Groot, R., Farber, S., Grasso, M., Hannon, B., Limburg, K., Naeem, S., O'Neill, R.V., Paruelo, J., Raskin, R.G., Sutton, P. and van den Belt, M. 1997. The value of the world's ecosystem services and natural capital. Nature 387: 253-260. Cunningham, M. 2009. Personal communication. Department of Zoology and Entomology, Qwaqwa Campus, University of the Free State.

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Cunningham, M. and Vences, M. 2006. From Berg to Karoo – mitochondrial DNA perspective on speciation in Vandijkophrynus. Proceedings of the 8th Conference of the Herpetological Association of Africa. Potchefstroom, Free State, South Africa, 24- 27 November 2006. Dallas, H.F. 2007. Research on the Rapid Biological Assessment of Water Quality Impacts in Streams and Rivers. In (Ed) Water Research Commission, Pretoria. WRC Report no. 422/1/98. Darwall, W.R.T., Smith, K.G., Tweedle, D. and Skelton, P. 2009. The status and distribution of freshwater biodiversity in Southern Africa. Gland, Switzerland: IUCN and Grahamstown, South Africa: SAIAB. de La Rey, P.A., Taylor, J.C., Laas, A., van Rensburg, L. and Vosloo, A. 2004. Determining the possible application value of diatoms as indicators of general water quality: A comparison with SASS 5. Water SA 30: 325-332. Dickens, C.W.S. and Graham, M.P. 2002. The South African Scoring System (SASS) version 5 rapid bioassessment method for rivers. African Journal of Aquatic Science 27: 1-10. Dixit, S.S., Smol, J.P., Kingston, J.C. and Charles, D.F. 1992. Diatoms: Powerful indicators of environmental change. Environmental Science and Technology 26: 23-33. Frost, D.R., Grant, T., Faivovich, J., Bain, R.H., Haas, A., Haddad, C.F.B., de Sa, R.O., Channing, A., Wilkinson, M., Donellan, S.C., Raxworthy, C.J., Campbell, J.A., Blotto, B.L., Moler, P., Drewes, R.C., Nussbaum, R.A., Lynch, J.D., Green, D.M. and Wheeler, W.C. 2006. The Amphibian Tree of Life. Bulletin of the American Museum of Natural History, no. 297. Gibb, A. 2008. Environmental Impact Assessment for the Proposed Upgrade of the Sani Pass Road (P318): Phase 2. Draft Scoping Report, project no. J27344. In (Ed) Harrison, J.A., Burger, M., Minter, L.R., de Villiers, A.L., Baard, E.H.W., Scott, E., Bishop, P.J. and Ellis, S. 2001. Conservation Assessment and Management Plan for Southern African Frogs: Final Report. IUCN/SSC Conservation Breeding Specialist Group, Apple Valley, Minnesota. Harvey, J. 2009. Personal communication. Pietermaritzburg. IUCN. 2008. IUCN Redlists. www.iucnredlists.org Jha, M. 2003. Ecological and toxicological effects of suspended and bedded sediments on aquatic habitats: A concise review for developing water quality criteria for suspended and bedded sediments (SABS). In (Ed) US EPA, Office of Water draft report. August, 2003. Macfarlane, D.M., Kotze, D.C., Ellery, W.N., Walters, D., Koopman, V., Goodman, P. and Goge, C. 2007. WET-Health: A technique for rapidly assessing wetland health. In (Ed) Water Research Commission, Pretoria. WRC Report no. TT 340/08. Minter, L.R., Burger, M., Harrison, J.A., Braack, H.H., Bishop, P.J. and Kloefder, D. 2004. Atlas and Red Data Book of the Frogs of South Africa, Lesotho and Swaziland. 9SI/MAB SERIES Smithsonian Institute, Washington, U.S.A. National Environmental Management Act. 1998. RSA Government Gazette No. 107 of 1998: 27 November 1998 No. 19519. Cape Town, RSA. National Water Act. 1998. RSA Government Gazette No. 36 of 1998: 26 August 1998, No. 19182. Cape Town, RSA. Pike, T. 2008. Personal communication. Pietermaritzburg. Rott, E. 1991. Methodological aspects and perspectives in the use of periphyton for monitoring and protecting rivers. In: Whitton, B.A., Rott, E., and Friedrich, G., Use of algae for monitoring rivers. Institüt für Botanik, University of Innsbruk. 9-16. Round, F.E. 1993. A Review and Methods for the Use of Epilithic Diatoms for Detecting and Monitoring Changes in River Water Quality: Methods for the examination of water and associated materials. HMSO Publications, London. Skelton, P.H. 2001. Complete Guide to the Freshwater Fishes of Southern Africa. Struik Publishers, Cape Town.

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Swartz, E. 2007. Psuedobarbus quathlambae. IUCN. 2008 IUCN Red List of Threatened Species. Available from www.iucnredlist.org Tarrant, J., Cunningham, M. and du Preez, L.H. In Press. Maluti Mystery: A systematic review of Amietia vertebralis (Hewitt, 1927) and Strongylopus hymenopus (Boulenger, 1920) (Anura: Pyxicephalidae). Taylor, J.C. 2009. Personal communication. University of the North West, South Africa. Taylor, J.C., Harding, W.R. and Archibald, C.G.M. 2007. A methods manual for the collection, preparation and analysis of diatom samples Version 1.0. In (Ed) Water Research Commission, Pretoria. TT 281/07. Tilman, D., Kilham, S.S. and Kilham, P. 1982. Phytoplankton community ecology: The role of limiting nutrients. Annual Review of Ecology and SYstematics 13: 349-372. van Dijk, D.E. 2008. Clades in Heleophrynid Salientia. African Journal of Herpetology 57 (1): 43-48. WRC 2004. Assessment of the South African Diatom Collection. In (Ed) Water Research Commission, Pretoria. WRC Report no. K8/508/2004.

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9. Appendices

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APPENDIX 1. Benthic diatom flora data

Table 1A: Full species lists and counts of all diatom taxa found at the aquatic biomonitoring site on the Mkhomazana and Sani Rivers during the wet season for the Sani Pass project. Site Site 03 Site 02 Taxon Site 01 Mkhomazana Mkhomazana Sani River River @ SA River source Border Achnanthes standerii Cholnoky 2 0 1 Achnanthidium minutissimavar. affinis(Grunow) Bukhtyarova 0 0 18 Achnanthidium minutissimum (Kützing) Czarnecki 60 197 7 Achnanthidium rivulare Potapova &Ponader 0 21 7 Adlafia bryophila (Petersen) Moser, Lange- Bertalot & Metzeltin 4 0 0 Amphora montana Krasske 0 0 1 Caloneis sp. 1 0 0 Cocconeis placentula Ehrenberg 0 0 13 Cocconeis placentula var.euglypta(Ehrenberg)Grunow 0 0 239 Cymbella cymbiformis Agardh 0 0 0 Cymbella kappii (Cholnoky) Cholnoky 7 0 1 Denticula kuetzingii Grunow 12 0 0 Encyonema krasskei (Krammer) Krammer 1 0 0 Encyonema sinensis (Bleisch) DG Mann 0 96 0 Encyonema sp. 1 0 0 Encyonopsis microcephala (Grunow) Krammer 62 0 1 Encyonopsis sp. 6 0 0 Eolimna minima (Grunow) Lange-Bertalot 0 0 0 Eunotia silvahercynia Nörpel Van Sull & Lange-Bertalot 0 0 5 Fragilaria biceps (Kützing) Lange-Bertalot 0 0 1 Fragilaria capucina Desmazieres 0 5 0 Fragilaria capucina var. vaucheriae (Kützing) Lange-Bertalot 0 0 3 Fragilaria crotonensis Kitton 0 0 18 Fragilaria rumpens (Kützing) Carlson 0 4 0 Fragilaria ungeriana Grunow 0 0 1 Frustulia vulgaris (Thwaites) De Toni 0 0 1 Gomphonema clavatum Ehrenberg 1 0 2 Gomphonema parvulum (Kützing) Kützing 2 0 0 Gomphonema pumilum var. rigidum Reichardt & Lange-Bertalot 195 0 0 Gomphonema sp. 0 0 20 Gomphonema venusta Passy, Kociolek & Lowe 38 0 0 Navicula cryptocephala Kützing 2 0 1

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Nitzschia acidoclinata Lange-Bertalot 0 2 0 Nitzschia linearis (Agardh) W.M.Smith 1 1 0 Nitzschia sp. 5 0 0 Planothidium lanceolatum (Brébisson) Lange- Bertalot 0 1 0 Reimeria sinuata (Gregory) Kociolek & Stoermer 0 73 58 Tabellaria flocculosa (Roth) Kützing 0 0 2

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APPENDIX 2. Macroinvertebrate data

Appendix 2A. Summary of macroinvertebrate taxa found in the Mkhomazana River with reference to site 03. Order Family TURBELLARIA Turbellaria ANNELIDA Oligochaeta ANNELIDA Leech CRUSTACEA Potamonautidae HYDRACARINA Hydracarina PLECOPTERA Notonemouridae PLECOPTERA Perlidae EPHEMEROPTERA Baetidae EPHEMEROPTERA Caenidae EPHEMEROPTERA Heptageniidae EPHEMEROPTERA Leptophlebiidae EPHEMEROPTERA Tricorythidae ODONATA Aeshnidae HEMIPTERA Corixidae HEMIPTERA Pleidae TRICHOPTERA Hydropsychidae TRICHOPTERA Leptoceridae COLEOPTERA Elmidae/Dryopidae COLEOPTERA Gyrinidae COLEOPTERA Hydrophilidae COLEOPTERA Psephenidae DIPTERA Blepharoceridae DIPTERA Ceratopogonidae DIPTERA Chironomidae DIPTERA Culicidae DIPTERA Muscidae DIPTERA Simuliidae DIPTERA Tabanidae

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APPENDIX 3. Freshwater ecosystem localities

Appendix 3A. List of the different types of freshwater ecosystems situated along the Sani Pass road. The position of each system is given relative to the road in addition to co- ordinates in decimal degrees (WGS84). Type Position Latitude (S) Longitude (E) Non-perennial river Lower -29.64614 29.42913 Non-perennial river Lower -29.64582 29.42878 Non-perennial river Lower -29.64551 29.42850 Non-perennial river Lower -29.64332 29.42580 Non-perennial river Lower -29.64047 29.42328 Perennial river Lower -29.63829 29.42222 Non-perennial river Lower -29.63739 29.42169 Non-perennial river Lower -29.63445 29.41879 Non-perennial river Lower -29.63432 29.41860 Hillslope seepage wetland Lower -29.63351 29.41776 Hillslope seepage wetland Lower -29.63320 29.41733 Non-perennial river Lower -29.63118 29.41423 Non-perennial river Lower -29.62950 29.41314 Non-perennial river Lower -29.62971 29.41129 Hillslope seepage wetland Lower -29.62889 29.40839 Hillslope seepage wetland Lower -29.62857 29.40714 Hillslope seepage wetland Lower -29.62829 29.40640 Hillslope seepage wetland Lower -29.62791 29.40468 Non-perennial river Lower -29.62803 29.40403 Perennial river Lower -29.62746 29.40347 Non-perennial river Lower -29.62602 29.40136 Non-perennial river Lower -29.62523 29.40066 Non-perennial river Lower -29.62376 29.39791 Hillslope seepage wetland Lower -29.62275 29.39707 Non-perennial river Lower -29.62264 29.39426 Hillslope seepage wetland Lower -29.62289 29.39341 Non-perennial river Lower -29.62292 29.39286 Non-perennial river Lower -29.62279 29.39270 Non-perennial river Lower -29.62186 29.39144 Hillslope seepage wetland Lower -29.62104 29.38977 Hillslope seepage wetland Lower -29.62083 29.38754 Non-perennial river Lower -29.62089 29.38739 Hillslope seepage wetland Lower -29.62021 29.38593 Non-perennial river Middle -29.61868 29.38220 Non-perennial river Middle -29.61783 29.37909 Hillslope seepage wetland Middle -29.61691 29.37814 Hillslope seepage wetland Middle -29.61402 29.37493 Hillslope seepage wetland Middle -29.61480 29.37557

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Sani Aquatic Baseline Biodiversity Assessment 2010

Non-perennial river Middle -29.61496 29.37547 Perennial river Middle -29.61329 29.36847 Perennial river Middle -29.61017 29.36254 Perennial river Middle -29.60887 29.36083 Hillslope seepage wetland Middle -29.60874 29.36052 Perennial river Middle -29.60707 29.35494 Non-perennial river Middle -29.60447 29.34811 Non-perennial river Middle -29.60399 29.34499 Non-perennial river Upper -29.60297 29.34180 Perennial river Upper -29.60301 29.33564 Non-perennial river Upper -29.60220 29.32987 Non-perennial river Upper -29.60181 29.32730 Non-perennial river Upper -29.60123 29.32538 Non-perennial river Upper -29.60073 29.32359 Non-perennial river Upper -29.59959 29.32230 Perennial river Upper -29.59909 29.32114 Non-perennial river Upper -29.59818 29.31597 Hillslope seepage wetland Upper -29.59792 29.31508 Non-perennial river Upper -29.59774 29.31390 Perennial river Upper -29.59859 29.30915 Non-perennial river Upper -29.59980 29.30782 Non-perennial river Upper -29.60041 29.30777 Non-perennial river Upper -29.60067 29.30799 Hillslope seepage wetland Upper -29.60126 29.30745 Hillslope seepage wetland Upper -29.60069 29.30702 Non-perennial river Upper -29.60062 29.30688 Perennial river Upper -29.59919 29.30483 Perennial river Upper -29.59580 29.30229 Non-perennial river Upper -29.59575 29.30222 Non-perennial river Upper -29.59402 29.30016 Non-perennial river Upper -29.59316 29.29923 Non-perennial river Upper -29.59219 29.29767 Perennial river Upper -29.59126 29.29550 Non-perennial river Upper -29.58923 29.29435

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