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SLANG RIVER LOW-LEVEL CROSSING

ECOLOGICAL IMPACT ASSESSMENT

Prepared for:

Afri-Coast Engineers SA (Pty) Ltd 14 Rose Street (Cnr Rose & Havelock Streets)

Central, Port Elizabeth, 6001

On behalf of

Eastern Cape Department of Roads and Public Works Qhasana Building, Independence Avenue, Bhisho, 5605

Prepared by:

Coastal and Environmental Services (Pty) Ltd, trading as

EOH Coastal & Environmental Services 13 Stanley street, Richmond Hill, Port Elizabeth, 6001

Also in Grahamstown, East London, Gauteng, Cape Town and Maputo (Mozambique)

www.cesnet.co.za

January 2016

http://www.cesnet.co.za/

This Report should be cited as follows: EOH Coastal & Environmental Services, January 2016: Slang River low-level crossing Ecological Impact Assessment, EOH CES, Port Elizabeth.

Slang River low-level crossing Ecological Impact Assessment – January 2016

EOH Coastal & Environmental Services Slang River low-level crossing i

REVISIONS TRACKING TABLE

EOH Coastal and Environmental Services

Report Title: Slang River low-level crossing Ecological Impact Assessment Report Version: Final Draft Project Number: 287

Name Responsibility Signature Date

Ms. Tarryn Martin Reviewer

September 2015

Mrs. Kim Brent Lead Author

August / September 2015

Ms. Belinda Huddy Report Assistance

July 2015

Mr Craig Sholto-Douglas

Wetland Delineation

January 2016

Copyright This document contains intellectual property and propriety information that are protected by

copyright in favour of EOH Coastal & Environmental Services (CES) and the specialist consultants. The document may therefore not be reproduced, used or distributed to any third party without the prior written consent of CES. The document is prepared exclusively for submission to Africoast

Engineers Pty (Ltd) in South Africa and the Eastern Cape Department of Roads and Public Works, and is subject to all confidentiality, copyright and trade secrets, rules intellectual property law and

practices of South Africa.


EOH Coastal & Environmental Services Slang River low-level crossing ii

THE PROJECT TEAM Mrs Kim Brent (Lead Author) Kim holds a BSc degree with majors in Botany and Geography as well as a BSc (Hons) degree in Botany focussing on Environmental Management and GIS systems; both from NMMU. Her honours year focussed on Environmental impact assessments, environmental management and Geographic Information systems. Kim‘s interests include Environmental impact assessments, Geographic information systems and Botanical assessments. Kim has over 4 years‘ experience in the consultancy environment and is currently employed in the Port Elizabeth office of CES. Ms Belinda Huddy (Report Assistance) Belinda holds an MPhil in Environmental, Society and Sustainability and a Bachelor of Business Science (Hons) in Economics, both obtained from the University of Cape Town. Her master's dissertation explored alternative values attached to the Cape Town Talent Exchange. Her honours thesis investigated the determinants of the success and failures of the bio-diesel industry, focusing on a jatrohpa plantation in Zambia. Courses in her master's degree include Theory and Practice of Environment Management, Managing Complex Human-Ecological Systems, Environmental Law and Cultural Geography. The relevant courses in her honours degree included Environmental Economics and Natural Resource Economics. Ms Tarryn Martin Pri.Sci.Nat (Reviewer) Tarryn holds a BSc (Botany and Zoology), a BSc (Hons) in African Vertebrate Biodiversity and an MSc with distinction in Botany from Rhodes University. Tarryn‘s Master‘s thesis examined the impact of fire on the recovery of C3 and C4 Panicoid and non-Panicoid grasses within the context of climate change for which she won the Junior Captain Scott-Medal (Plant Science) for producing the top MSc of 2010 from the South African Academy of Science and Art as well as an Award for Outstanding Academic Achievement in Range and Forage Science from the Grassland Society of Southern Africa. She conducts vegetation assessments including vegetation and sensitivity mapping to guide developments and thereby minimise their impacts on sensitive vegetation. Tarryn has conducted a number of vegetation and impact assessments in Mozambique (to IFC standards) which include the Lurio Forestry Project in Nampula, the Syrah Graphite Mine in Cabo del Gado and the Baobab Iron Ore Mine in Tete, Mozambique. Tarryn has also co-designed and implemented the Terrestrial Monitoring Program for Kenmare, MOMA, a heavy minerals mine in Mozambique. This monitoring program includes an assessment of forest health. She has also worked on the Lesotho Highlands Development Authority botanical baseline survey for phase 2 of the Lesotho Highlands Water Project. Mr Craig Sholto-Douglas (Wetland Delineation and Assessment) Craig holds a BSc (Env Sci and Zoology) and a BSc (Hons) in Environmental Science. He is currently completing his MSc in Environmental Science, focussing on factors influencing survivorship of Portulacaria afra (Spekboom) cuttings, in attempts to restore degraded lands in the Greater Addo Elephant National Park. His academic background includes courses in Urban Forestry and Greening, Non-Timber Forest Products, Community-Based Natural Resource Management and G.I.S. Research projects include a leopard (Panthera pardus) population survey and invasive plant species analyses. Craig has consulting experience in the restoration ecology and natural resource management fields, with focus on the Subtropical Thicket Restoration Project (STRP). Since working at EOH CES, Craig has been involved in Wind Farm ECO work, EIA‘s and a number of faunal specialist studies. Craig has been involved in numerous wetland delineations and assessments in the Eastern Cape, including the Oyster Bay WEF Ecological Assessment and SANRAL National Road Upgrade Wetland Assessments.


EOH Coastal & Environmental Services Slang River low-level crossing i

ENVIRONMENTAL ASSESSMENT PRACTITIONER DECLARATION OF INDEPENDENCE

Role on Study Team Declaration of independence

Report Reviewer I TARRYN MARTIN declare that I am an independent consultant and have no business, financial, personal or other interest in the proposed development of Social Housing in the Eastern Cape, application or appeal in respect of which I was appointed other than fair remuneration for work performed in connection with the activity, application or appeal. There are no circumstances that compromise the objectivity of my performing such work. SIGNATURE:

Report production I KIM BRENT declare that I am an independent consultant and have no business, financial, personal or other interest in the proposed development of Social Housing in the Eastern Cape, application or appeal in respect of which I was appointed other than fair remuneration for work performed in connection with the activity, application or appeal. There are no circumstances that compromise the objectivity of my performing such work. SIGNATURE:

Report production I BELINDA HUDDY declare that I am an independent consultant

and have no business, financial, personal or other interest in the proposed development of Social Housing in the Eastern Cape, application or appeal in respect of which I was appointed other than fair remuneration for work performed in connection with the activity, application or appeal. There are no circumstances that compromise the objectivity of my performing such work. SIGNATURE:

Report production I CRAIG SHOLTO-DOUGLAS declare that I am an independent

consultant and have no business, financial, personal or other interest in the proposed development of Social Housing in the Eastern Cape, application or appeal in respect of which I was appointed other than fair remuneration for work performed in connection with the activity, application or appeal. There are no circumstances that compromise the objectivity of my performing such work. SIGNATURE:


EOH Coastal & Environmental Services Slang River low-level crossing ii

EXECUTIVE SUMMARY Background The Slang River crossing which is located on the district road (DR) 01763, North of Oyster Bay and between the Kouga Local Municipality and Humansdorp has been damaged by a flood event and numerous heavy rain events. Consequently, a section of the crossing has become unusable. EOH Coastal & Environmental Services (CES) has been approached by Africoast Engineers on behalf of the Eastern Cape Department of Roads and Public Works to to apply for environmental authorization by conducting a Basic Assessment and all related specialist assessments (ecological) for the rehabilitative maintenance to the Slang River low-level crossing. The proposed reconstruction works will entail: the establishment of a camp site (including storage area); rehabilitation of the damaged crossing, with work being limited to the existing footprint; and a temporary diversion of stream flow through the construction area using temporary pipes. A water use authorisation in terms of the National Water Act (Act 36 of 1998) sections 21 (i) and (c) will be applied for as the proposed bridge rehabilitation impedes or diverts the natural flow of the watercourse and also alters the bed, banks, course and characteristics of a water course. Objective and approach The main objective of this report is to assess the Present Ecological State (PES) of the Slang River as well as the potential impact that the proposed reconstruction of the low-level crossing may have on the river and the riparian and terrestrial habitat. The proposed project and surrounding areas were described using a two-phased approach. Firstly, a desktop assessment of the project area was conducted in terms of current vegetation classifications and biodiversity programmes and plans. Information was also collected to determine the PES and Ecological Importance and Sensitivity (EIS) of the project area. These analyses were based on the models developed by the Department of Water and Sanitation, with the results producing various ratings. Secondly, site visits were conducted to assess the actual ecological state, current land-use, identify potential sensitive ecosystems and identify plant species associated with the proposed project activity. The ecological sensitivity of the study area was determined on a broad scale. The approach identifies zones of, high, moderate and low sensitivity according to a system developed by CES and used in numerous proposed development studies. Key findings The Present Ecological State (PES) of the Slang River and its associated wetlands is described as largely modified (Category D). A large loss of natural habitat, biota and basic ecosystem functions has occurred. Vegetation composition has been largely altered and introduced alien and/or ruderal species dominate the site. The area is highly degraded as a result of direct and indirect anthropogenic activities and has consequently been assigned a moderate to low sensitivity. The adjacent road and agricultural land has been classified as having a low sensitivity due to their degraded and transformed nature. Reduction in flow due to impoundments upstream and downstream of the project area, algal growth within the river, erosion and sediment deposition, alien infestation, and current land use (e.g. agricultural practice) have contributed to the modification of the river and wetland systems. A total of twenty four (24) species were identified within the project area. Twelve (12) of these species were identified as species of conservation concern listed on the South African Red Data and is classified as species of ―Least Concern‖ and one (1) species as declining. None of the identified species are protected in the Eastern Cape PNCO list or on the NEM:BA list. No protected tree species were recorded to occur within the project area. Four (4) alien species were identified on site.


EOH Coastal & Environmental Services Slang River low-level crossing iii

Identified impacts Associated impacts identified with the proposed low-level crossing were not deemed insurmountable. No high rated impacts were identified and all other impacts (pre-mitigation) are easily mitigated. A summary of impacts associated with the low level crossing pre and post mitigation, as well as the no-go alternative is included below.

Summary of impacts associated with the low level crossing pre and post mitigation. The no-go alternative has also been included for comparative purposes.

IMPACTS WITHOUT

MITIGATION WITH MITIGATION NO-GO

CONSTRUCTION PHASE

Loss of Riparian vegetation Low Low Moderate

Loss of Alien vegetation Low + Moderate + High

Loss of floral biodiversity (general)

Moderate Low Low

Loss of SCC Moderate Low Low

Impacts on sensitive ecosystems in terms of erosion and sedimentation

Moderate Low High

Impacts on sensitive ecosystems in terms of pollution

Moderate Low Moderate

Temporary diversion of stream flow

Moderate Moderate Moderate

Physical destruction of wetland habitat

Moderate Low High

Sedimentation and erosion within the wetland system

Moderate Low Moderate

OPERATIONAL PHASE

Invasion of alien plant species Moderate Low + High

Reduction of erosion and sedimentation

Low + Moderate + High


EOH Coastal & Environmental Services Slang River low-level crossing iv

TABLE OF CONTENTS 1. INTRODUCTION ..................................................................................................................... 1

1.1 Background ..................................................................................................................... 1 1.2 Project description and locality ........................................................................................ 1 1.3 Objectives and Terms of Reference................................................................................. 4 1.4 Approach ......................................................................................................................... 4 1.5 Limitations and assumptions ........................................................................................... 7

2 RELEVANT LEGISLATION .................................................................................................... 8 2.1 National Environmental Management Act (No. 107 of 1998) ........................................... 8 2.2 National Environmental Management: Biodiversity Act (No. 10 of 2004) ......................... 8 2.3 National Water Act (No.36 of 1998) ................................................................................. 9 2.4 National Forest Act (No.84 of 1998)............................................................................... 10 2.5 Species of Conservation Concern (SCC) ....................................................................... 10

3 DESCRIPTION OF THE PHYSICAL ENVIRONMENT .......................................................... 13 3.1 Climate .......................................................................................................................... 13 3.2 Geology and Soils (Source: www.geoscience.org.za, AGIS 2015) ................................ 13 3.3 Topography ................................................................................................................... 14 3.4 Socio-economic aspects and Current land use .............................................................. 14

4 DESCRIPTION OF THE ECOLOGICAL ENVIRONMENT .................................................... 17 4.1 Aquatic Environment ..................................................................................................... 17

4.1.1 Water Management Area (WMA) ............................................................................... 17 4.1.2 Background to the Slang River within the project area ............................................... 18 4.1.3 The Slang Estuary ..................................................................................................... 19

4.2 Terrestrial and Riparian environment ............................................................................. 22 4.2.1 SANBI Vegetation Map .............................................................................................. 22 4.2.2 Subtropical Thicket Ecosystem Programme (STEP) .................................................. 23 4.2.3 Eastern Cape Biodiversity Conservation Plan (ECBCP) ............................................ 25 4.2.4 Present Ecological State (PES) of the Slang River and associated wetlands ............. 28

4.3 Site survey: description of vegetation/land cover ........................................................... 29 4.3.1 Riparian Vegetation ................................................................................................... 29

4.4 Floristics ........................................................................................................................ 34 4.4.1 Species of Conservation Concern .............................................................................. 34 4.4.2 Alien Species ............................................................................................................. 36

5 WETLAND DELINEATION AND ASSESSMENT ................................................................. 38 5.1 Approach ....................................................................................................................... 38 5.2 Wetland definition .......................................................................................................... 38 5.3 Wetland Importance ...................................................................................................... 38 5.4 Tools available to define wetlands and watercourses .................................................... 39

5.4.1 National Freshwater Ecosystem Priority Areas .......................................................... 39 5.4.2 WET-Health and Present Ecological State ................................................................. 40

6 PHYSICAL DESCRIPTION OF WETLAND AND AQUATIC ENVIRONMENT ...................... 45 6.1 Introduction .................................................................................................................... 45 6.2 Collection of site data .................................................................................................... 47 6.3 Present Ecological State (PES) ..................................................................................... 47

6.3.1 Hydrology .................................................................................................................. 47 6.3.2 Geomorphology ......................................................................................................... 47 6.3.3 Vegetation ................................................................................................................. 48 6.3.4 Overall PES of Identified Wetlands ............................................................................ 49 6.3.5 Photographs of Wetlands........................................................................................... 52

7 BIODIVERSITY AND SENSITIVITY ASSESSMENT ............................................................ 54 7.1 Sensitivity analysis and site sensitivity ........................................................................... 54

8 IMPACT IDENTIFICATION AND ASSESSMENT ................................................................. 55 8.1 Planning and Design Phase .......................................................................................... 55 8.2 Construction phase ........................................................................................................ 55

8.2.1 Issue 1: Loss of Vegetation communities ................................................................... 55 8.2.2 Issue 2: Loss of Biodiversity ...................................................................................... 56 8.2.3 Issue 3: Disruption of Ecosystem Function and Process ............................................ 58


EOH Coastal & Environmental Services Slang River low-level crossing v

8.2.4 Issue 4: Impacts on wetlands and wetland function ................................................... 60 8.3 Operational Phase ......................................................................................................... 61

8.3.1 Issue 4: Disruption of Ecosystem Function and Process ............................................ 61 8.4 Decommissioning Phase ............................................................................................... 62 8.5 Cumulative Impacts ....................................................................................................... 62

9 IMPACT STATEMENT, CONCLUSION & RECOMMENDATIONS ....................................... 63 9.1 Conclusions ................................................................................................................... 63 9.2 Current status ................................................................................................................ 63 9.3 Comparison of impacts .................................................................................................. 63 9.4 Invasion of alien species ................................................................................................ 64

10 REFERENCES...................................................................................................................... 65

LIST OF FIGURES Figure 1.1: Locality map illustrating the position of the project area (Source: Africoast Engineers). ................ 3 Figure 3.1: Map indicating the geology of the proposed ................................................................................. 14 Figure 3.2: Landcover classification of the proposed project area in relation to the surrounding area. .......... 15 Figure 4.1: Map indicating the location of the project area including the identification of sensitive

environments (Source: Africoast Engineers) ........................................................................................... 20 Figure 4.2: Map indicating the location of the project area in the relevant Water Management Area (Source:

Africoast Engineers) ................................................................................................................................ 21 Figure 4.3: National Vegetation Map illustrating the vegetation type found within the project area. .............. 23 Figure 4.4: Regional Vegetation Map illustrating the vegetation type found within the project area as

classified by STEP (2006). ...................................................................................................................... 24 Figure 4.5: Transformed areas as classified by STEP (2006). ........................................................................ 25 Figure 4.6: Critical Biodiversity Areas (CBA) as classified by ECBCP (2007). ............................................... 26 Figure 4.7: BLMC Land management classes as classified by ECBCP (2007). ............................................. 27 Figure 5.1: The HGM types for South African Inland wetlands (SANBI, 2009). .............................................. 41 Figure 5.2: The steps involved in the WET-Health Level 1 rapid assessment (MacFarlane et al. 2007). ...... 43 Figure 6.1: National Freshwater Ecosystem Priority Areas (NFEPA) wetlands and wetland conditions ........ 46 Figure 6.2: Delineated wetlands and sensitive areas ...................................................................................... 51

LIST OF TABLES Table 1.1: Description of A – F ecological categories based on Kleynhans et al., (2005) ................................ 4 Table 1.2: Criteria used for the analysis of the sensitivity of the area ............................................................... 6 Table 2.1: NEMBA classes and explanations.................................................................................................. 11 Table 2.2: South African Red Data List Categories (SANBI, 2013) ................................................................ 11 Table 4.1: Present Ecological State (PES) of the Slang River ........................................................................ 29 Table 4.2: Species recorded on site. Those recorded in the Red data list, PNCO, CITES, NEMBA and CARA

has been classified according to each list and discussed below the table. ............................................. 34 Table 4.3: Alien invasive species present on site ............................................................................................ 36 Table 5.1: Description of A – F ecological categories based on Kleynhans (1996, 1999). ............................. 44 Table 6.1: Overall PES scores and ratings for the assessed wetlands. .......................................................... 50 Table 9.1: Summary of impacts associated with the low level crossing pre and post mitigation. The no-go

alternative has also been included for comparative purposes. ............................................................... 64


EOH Coastal & Environmental Services Slang River low-level crossing 1

1. INTRODUCTION

1.1 Background The Slang River crossing is located on the district road (DR) 01763, North of Oyster Bay and between the Kouga Local Municipality and Humansdorp (Figure 1.1). Since 2011, the Slang River crossing has been damaged by a flood event and since then a number of heavy rain events contributed to the condition of the current low-level crossing. Consequently, a section of the crossing has become unusable and this is undermining the integrity of the crossing to support vehicle traffic (See plate 1 below). This also poses a threat to farmers in terms of safety as well as the local public that uses this road.

Plate 1: Photos of the damaged Slang River Crossing (Source: Africoast Engineers)

1.2 Project description and locality EOH Coastal & Environmental Services (CES) has been approached by Africoast Engineers on behalf of the Eastern Cape Department of Roads and Public Works to to apply for environmental authorization by conducting a Basic Assessment and all related specialist assessments (Ecological) for the rehabilitative maintenance to the Slang River low-level crossing. The proposed low-level crossing is located along a ―dirt‖ or un-tarred district road across the perennial Slang River (or Slangrivier), approximately 20km north east of the coastal town of Oyster Bay, in the Eastern Cape.



The area falls within Ward 1 of the Kouga Local Municipality within the broader Cacadu District Municipality, otherwise known as Sarah Baartman District Municipality. The population in the Kouga Local Municipality is approximately 98 588 with an average growth rate 2.4% per annum, which is relatively high in comparison to the district and provincial growth rates of 1.1% and 0.3%, respectively. The Kouga Local Municipality is the Water Services Authority (WSA) for the jurisdiction, and is thus responsible for the provision of water services as well as for drafting all water services development plans for the area. The proposed reconstruction works will entail (in summary) (Source: Africoast Engineers) –

Camp site establishment (including storage area)

Rehabilitation of the damaged crossing, with work being limited to the existing footprint

Temporary diversion of stream flow through the construction area using temporary

pipes

A water use authorisation in terms of the National Water Act (Act 36 of 1998) sections 21 (i) and (c) will be applied for as the proposed bridge rehabilitation impedes or diverts the natural flow of the watercourse and also alters the bed, banks, course and characteristics of a water course.



Figure 1.1: Locality map illustrating the position of the project area (Source: Africoast Engineers).



1.3 Objectives and Terms of Reference The main objective of this report is to assess the Present Ecological State (PES) of the Slang River as well as the potential impact that the proposed reconstruction of the low-level crossing may have on the river and the riparian and terrestrial habitat. The following terms of reference were used for the objectives of this study:

Describe the study area in terms of land cover, vegetation and aquatic features. This aspect of the report will specifically include the identification of -

o Areas of high biodiversity; o The presence of species of conservation concern, including sensitive, endemic and

protected species; o Rapid assessment of river/riparian integrity and assessment of ecological importance and

sensitivity. o The presence of areas sensitive to invasion by alien species; and o The presence of conservation areas and sensitive habitats where disturbance should be

avoided or minimised.

Review relevant legislation, policies, guidelines and standards.

An assessment of the potential direct and indirect impacts resulting from the proposed development both on the footprint and the immediate surrounding area during construction and operation and

A detailed description of appropriate mitigation measures that can be adopted to reduce negative impacts for each phase of the project, where required

1.4 Approach The proposed project and surrounding areas were described using a two-phased approach. Firstly, a desktop assessment of the project area was conducted in terms of current vegetation classifications and biodiversity programmes and plans. This included the consideration of:

The South African Vegetation Map (Mucina and Rutherford, 2006);

The Subtropical Thicket Ecosystem Programme (STEP, 2006)

The Eastern Cape Biodiversity Conservation plan (ECBCP, 2007)

The National Freshwater Ecosystem Priority Areas (NFEPA) project (2011/2014) Information was also collected to determine the PES and Ecological Importance and Sensitivity (EIS) of the project area. These analyses were based on the models developed by the Department of Water and Sanitation, with the results producing various ratings (A – F) and is summarised in Table 1.1 below. Table 1.1: Description of A – F ecological categories based on Kleynhans et al., (2005) ECOLOGICAL

CATEGORY ECOLOGICAL DESCRIPTION

MANAGEMENT

PERSPECTIVE

A

Unmodified, natural.

Protected systems; relatively

untouched by human hands; no

discharges or impoundments

allowed

B

Largely natural with few modifications. A small

change in natural habitats and biota may have

taken place but the ecosystem functions are

essentially unchanged.

Some human-related

disturbance, but mostly of low

impact potential

C

Moderately modified. Loss and change of natural

habitat and biota have occurred, but the basic

ecosystem functions are still predominantly

unchanged.

Multiple disturbances

associated with need for

socio-economic

development, e.g.



ECOLOGICAL

CATEGORY ECOLOGICAL DESCRIPTION

MANAGEMENT

PERSPECTIVE

D

Largely modified. A large loss of natural habitat,

biota and basic ecosystem functions has occurred.

impoundment, habitat

modification and water

quality degradation

E

Seriously modified. The loss of natural habitat,

biota and basic ecosystem functions is extensive. Often characterized by high

human densities or extensive

resource exploitation.

Management intervention is

needed to improve health,

e.g. to restore flow patterns,

river habitats or water quality

F

Critically / Extremely modified. Modifications have

reached a critical level and the system has been

modified completely with an almost complete loss

of natural habitat and biota. In the worst instances

the basic ecosystem functions have been

destroyed and the changes are irreversible.

Further to the above, a site visit was conducted (9 June 2015) to assess the actual ecological state, current land-use, identify potential sensitive ecosystems and identify plant species associated with the proposed project activity. During the site surveys, selected sites which represented natural habitats were sampled for species richness and abundance and vegetation structure. A stratified random sampling approach was adopted, whereby initial assumptions were made about the diversity of vegetation from satellite imagery, existing vegetation maps and previous studies conducted in the area. In this way the time available was used much more efficiently than in random sampling, but there is a risk of bias and the eventual results may simply ‗prove‘ the assumptions. The aim of this visit was to characterise and describe each vegetation community as well as identifying areas of high sensitivity and species of conservation concern. It is however, important to note areas of high sensitivity as well as species of conservation concern have been identified as far as possible, either from records from the project area or a review of their habitat requirements and whether or not these habitats occur in within the project area. The primary aim of this study was to identify whether areas of high sensitivity will be subject to significant impacts from the proposed activity. Aspects that would increase impact significance include:

Presence of plant species of conservation concern.

Vegetation types of conservation concern.

Areas of high biodiversity.

The presence of important process areas such as: o Ecological corridors o Water bodies (including wetlands & rivers) o Topographical features (especially steep and rocky slopes that provide niche habitats for

both plants and animals) Sensitivity assessment This section of the report explains the approach to determining the ecological sensitivity of the study area on a broad scale. The approach identifies zones of, high, moderate and low sensitivity according to a system developed by CES and used in numerous proposed development studies. It must be noted that the sensitivity zonings in this study are based solely on ecological characteristics and social and economic factors have not been taken into consideration. The sensitivity analysis described here is based on 10 criteria which are considered to be of importance in determining ecosystem and landscape sensitivity. The sensitivity criteria described in Table 1.2 below were applied to the study area. The entire site was then categorised into zones of HIGH, MODERATE or LOW sensitivity. Although very simple,



this method of analysis provides a good, yet conservative and precautionary assessment of the ecological sensitivity. Table 1.2: Criteria used for the analysis of the sensitivity of the area

CRITERIA LOW SENSITIVITY 1

MODERATE SENSITIVITY

5

HIGH SENSITIVITY 10

1 Topography Level, or even Undulating; fairly steep slopes

Complex and uneven with steep slopes

2 Vegetation - Extent or habitat type in the region

Extensive Restricted to a particular region/zone

Restricted to a specific locality / site

3 Conservation status of flora or habitats

Well conserved independent of conservation value

Not well conserved, moderate conservation value

Not conserved - has a high conservation value

4 Species of conservation concern - Presence and number

None, although occasional regional endemics

No endangered or vulnerable species, some indeterminate or rare endemics

One or more endangered and vulnerable species, or more than 2 endemics or rare species

5 Habitat fragmentation leading to loss of viable populations

Extensive areas of preferred habitat present elsewhere in region not susceptible to fragmentation

Reasonably extensive areas of preferred habitat elsewhere and habitat susceptible to fragmentation

Limited areas of this habitat, susceptible to fragmentation

6 Biodiversity contribution

Low diversity, or species richness

Moderate diversity, and moderately high species richness

High species diversity, complex plant and animal communities

7 Visibility of the site or landscape from other vantage points

Site is hidden or barely visible from any vantage points with the exception in some cases from the sea.

Site is visible from some or a few vantage points but is not obtrusive or very conspicuous.

Site is visible from many or all angles or vantage points.

8 Erosion potential or instability of the region

Very stable and an area not subjected to erosion.

Some possibility of erosion or change due to episodic events.

Large possibility of erosion, change to the site or destruction due to climatic or other factors.

9 Rehabilitation potential of the area or region

Site is easily rehabilitated.

There is some degree of difficulty in rehabilitation of the site.

Site is difficult to rehabilitate due to the terrain, type of habitat or species required to reintroduce.

10 Disturbance due to human habitation or other influences (Alien invasives)

Site is very disturbed or degraded.

There is some degree of disturbance of the site.

The site is hardly or very slightly impacted upon by human disturbance.

A Geographical Information System (GIS) map was then drawn up depicting the different zones of sensitivity using available aerial imagery and relating this to the information gathered from the field survey.



1.5 Limitations and assumptions This report is based on currently available information and, as a result, the following limitations and assumptions are implicit:–

1. The report is based on a project description taken from design specifications for the proposed low-level crossing provided to CES by the engineers, that has not yet been finalised, and which is likely to undergo a number of iterations and refinements before it can be regarded as definitive;

2. Faunal aspects has not been included in this report. 3. Species of conservation concern are difficult to find and difficult to identify, thus species

described in this report do not comprise an exhaustive list. It is almost certain that additional species of conservation concern will be found during construction and operation of the development.

4. For the sake of this study, one survey was deemed sufficient to determine the status of the study area.

5. Ecological descriptions of the natural environment are based on limited fieldwork and available literature.



2 RELEVANT LEGISLATION Environmental legislation relevant to the proposed Slang River low-level crossing is summarised below. Biodiversity Plans and Programmes are discussed in Chapter 4 where they are used to describe the desktop ecological conditions.

2.1 National Environmental Management Act (No. 107 of 1998) Relevant Sections of the Act: Section 2, 23, 24, 24-1, 28 -33 Applications for the Slang River low-level crossing:

Application of the NEMA principles (e.g. need to avoid or minimise impacts, use of the precautionary principle, polluter pays principle, etc.)

Application of fair decision-making and conflict management procedures are provided for in NEMA.

Application of the principles of Integrated Environmental Management and the consideration, investigation and assessment of the potential impact of existing and planned activities on the environment; socio-economic conditions; and the cultural heritage.

Implications for the proposed Slang River low-level crossing: o In terms of Section 28, every person who causes; has caused, or may cause significant

pollution or degradation of the environment must take reasonable measures to prevent pollution or rectify the damage caused.

2.2 National Environmental Management: Biodiversity Act (No. 10 of 2004) Relevant Sections of the Act: Section 50-62, 63-77, 75 Objectives of the Act The objectives of the Act include inter alia: To provide for:

The management and conservation of biological diversity within the Republic and of the components of such biological diversity;

o The use of indigenous biological resources in a suitable manner; o The fair and equitable sharing of benefits arising from bio-prospecting of genetic

material derived from indigenous biological resources; and o To give effect to ratified international agreements relating to biodiversity which are

binding on the Republic.

To provide for co-operative governance in biodiversity management and conservation; and

To provide for a South African National Biodiversity Institute to assist in achieving the objectives of the Act.

Threatened or protected ecosystems and species Sections 50-62 provide details relating to the protection of threatened or protected ecosystems and species. A person may not carry out a restricted activity involving a specimen of a listed threatened or protected species without a permit (Section 56-1). Alien and invasive species Sections 63-77 provide details relating to the alien and invasive species with the purpose of preventing the introduction and spread, managing and controlling, and eradicating alien and invasive species.



Implications for the Slang River low-level crossing: o An invasive species management, control and eradication plan for land/activities under their

control should be developed, as part of their environmental plans in accordance with section 11 of NEMA.

2.3 National Water Act (No.36 of 1998) Purpose of the Act (Section 2) The purpose of the Act is to ensure that the Nation‘s water resources are protected, used, developed, conserved and controlled in ways which take into account, including: d) Promoting sustainable use of water. g) Protect aquatic and associated ecosystems and their biological diversity. h) Reducing and preventing pollution and degradation of water resources. Protection of water resources (Section 12-20) Provides details of measures intended to ensure the comprehensive protection of all water resources, including the water reserve and water quality. With respect to the establishment of water quality objectives, objectives may relate to (Section 13):

the presence and concentration of particular substances in the water

the characteristics and quality of the water resource and the in-stream and riparian habitat

the characteristics and distribution of aquatic biota

the regulation and prohibition of in-stream and land-based activities which may affect the quantity and quality of the water resources

Section 19 deals with Pollution Prevention (Part 4) The person (including a municipality) who owns, controls occupies or uses the land in question, is responsible for taking reasonable measures to prevent pollution of water resources. If the measures are not taken, the catchment management agency concerned, may itself do whatever is necessary to prevent the pollution or remedy its effects and recover all reasonable costs from the persons responsible for the pollution. The ‗reasonable measures‘ which have to be taken may include measures to:

a) Cease, modify or control any act or process causing the pollution; b) Comply with any prescribed waste standard or management practice; c) Contain or prevent the movement of pollutants; d) Eliminate any source of the pollution; e) Remedy the effects of the pollution; and f) Remedy the effect of any disturbance to the bed and banks of a watercourse.

With respect to pollution of rivers, the following definition is relevant when considering the potential impacts of development on water resources. Pollution may be deemed to occur when the following are affected:

a) the quality, pattern, timing, water level and assurance of instream flow; b) the water quality, including the physical, chemical and biological characteristics of the

water; c) the character and condition of the in-stream and riparian habitat; d) the characteristics, condition and distribution of the aquatic biota.

The Act defines ‗instream habitat‘ as including the physical structure of a watercourse and the associated vegetation in relation to the bed of the watercourse. Riparian ecosystems ‗Riparian habitat‘ includes the physical structure and associated vegetation of the areas associated with a watercourse which are commonly characterised by alluvial soils, and which are inundated or flooded to an extent and with a frequency sufficient to support vegetation of species and physical structure distinct from those of adjacent land areas.

slang river low-level crossing ecological impact … river 287_ra090216/draft... · 2017-06-13 ·...

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