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 i Sani Pass - Aquatic Biodiversity Baseline Assessment 2010 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 i Sani Aquatic Baseline Biodiversity Assessment 2010 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 Sani Aquatic Baseline Biodiversity Assessment 2010 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