APPENDIX G2 FRESHWATER ECOLOGICAL INPUT · upgrade is located on two erven Erf 2454 (8– 444 m 2)...

APPENDIX G2

FRESHWATER ECOLOGICAL INPUT

FreshwaterCONSULTINGcc

Glencairn Hotel:

Freshwater ecological input to Basic Assessment

December 2017

Report compiled by: K. Snaddon, The Freshwater Consulting Group, P O Box 43935, Scarborough, 7975

Submitted to: SLR Consulting, Cape Town

Freshwater Consulting cc trading as “The Freshwater Consulting Group” (FCG) Partners: E Day, J L Ewart-Smith, C D Snaddon, D Ollis; Reg. No. 2007/064216/23

Glencairn Hotel Basic Assessment December 2017

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Table of Contents

TABLE OF CONTENTS .................................................................................................................. 2

1 INTRODUCTION ................................................................................................................... 4

1.1 Background and Approach ............................................................................................................................. 4

1.2 Limitations ..................................................................................................................................................... 5

1.3 Use of this Report .......................................................................................................................................... 5

1.4 Declaration of Independence ......................................................................................................................... 5

1.5 Specialist Details ............................................................................................................................................ 5

2 DESCRIPTION OF THE AFFECTED AQUATIC ECOSYSTEMS ...................................................... 6

2.1 General description of the site ....................................................................................................................... 6

2.2 Glencairnvlei outlet ........................................................................................................................................ 7

2.3 Delineation of wetlands ................................................................................................................................. 8

3 ASSESSMENT OF CONDITION AND IMPORTANCE OF THE GLENCAIRNVLEI OUTLET ............. 10

3.1 Methods .......................................................................................................................................................10 3.1.1 PES ................................................................................................................................................................... 10 3.1.2 EIS .................................................................................................................................................................... 11

3.2 Results ..........................................................................................................................................................12 3.2.1 PES ................................................................................................................................................................... 12 3.2.2 EIS .................................................................................................................................................................... 12

3.3 Buffer determination ....................................................................................................................................13

4 LEGISLATION AND GUIDELINES GOVERNING THE CONSERVATION AND MANAGEMENT OF RIVERS AND WETLANDS ........................................................................................................... 15

4.1 National Environmental Management Act (Act 107 of 1998 as amended by Act 62 of 2008) ........................15

4.2 Environmental Impact Assessment regulations (2014), as amended .............................................................15

4.3 Conservation of Agricultural Resources Act (Act 43 of 1983) .........................................................................15

4.4 National Environmental Management: Biodiversity Act (Act 10 of 2004) ......................................................15

4.5 Cape Nature Conservation Ordinance (Ordinance 19 of 1974; amended in 2000) .........................................16

4.6 National Water Act (1998) ............................................................................................................................16

4.7 Western Cape Provincial Spatial Development Framework (2014) ................................................................17

4.8 Biodiversity Spatial Plans ..............................................................................................................................18

5 DESCRIPTION OF PROPOSED DEVELOPMENT ..................................................................... 19

5.1 Roads ............................................................................................................................................................19

5.2 Water and Sewerage .....................................................................................................................................19

5.3 Stormwater ...................................................................................................................................................20

6 IMPACT ASSESSMENT ........................................................................................................ 22

6.1 Protocol for the assessment of impacts ........................................................................................................22

6.2 Description of probable impacts and mitigation measures ...........................................................................23


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6.2.1 Layout .............................................................................................................................................................. 23 6.2.2 Construction phase ......................................................................................................................................... 24 6.2.3 Operational Phase ........................................................................................................................................... 25 6.2.4 Cumulative impacts ......................................................................................................................................... 27

6.3 Results of assessment of impacts ..................................................................................................................27 6.3.1 Layout .............................................................................................................................................................. 27 6.3.2 Construction Phase ......................................................................................................................................... 28 6.3.3 Operational Phase ........................................................................................................................................... 31

7 WATER USE AUTHORISATION ............................................................................................ 33

7.1 Risk assessment matrix .................................................................................................................................33

7.2 Results of risk assessment .............................................................................................................................33

8 REHABILITATION AND MONITORING ................................................................................. 38

8.1 Rehabilitation ...............................................................................................................................................38 8.1.1 Re-shaping of bank slope ................................................................................................................................ 38 8.1.2 Removal of exotics and re-vegetation of cleared areas .................................................................................. 39

8.2 Monitoring ....................................................................................................................................................40

9 CONCLUSIONS AND RECOMMENDATIONS ......................................................................... 41

10 REFERENCES ................................................................................................................... 43

LIST OF FIGURES Figure 2.1 Overview of the Glencairn Hotel site, showing its location in relation to Glencairnvlei and the coastline. _ 6 Figure 2.2 Close up of the site, showing the location of the Glencairnvlei outlet (green polygon) in relation to the hotel site (red boundary). The western boundary of the outlet was delineated using indicators of vegetation, topography and hydrology. __________________________________________________________________________ 9 Figure 5.1 Proposed re-development of the Glencairn Hotel (November 2017). _____________________________ 21 Figure 8.1 (Left) Ecologs installed for stabilisation, and (below) Banks stabilised by geofabric, showing natural re-growth of indigenous species through the mat. _________________________________________________________ 39

LIST OF TABLES Table 3.1 Present Ecological State categories (from MacFarlane et al., 2009). _____________________________ 10 Table 3.2 Rating table used to rate ecological importance and sensitivity (EIS) (Rountree et al., 2013). _________ 11 Table 3.3 Ecological Importance and Sensitivity categories for wetlands (Rountree et al., 2013). ______________ 12 Table 3.4 PES scores for Glencairnvlei, following the Wet-Health protocol of MacFarlane et al. (2009). _________ 12 Table 3.5 Wetland EIS for Glencairnvlei. ___________________________________________________________ 13 Table 3.6 Results of the buffer width determination for Glencairnvlei outlet. The determination was done using the tool of MacFarlane et al. (2014). ____________________________________________________________________ 14 Table 6.1 Criteria used for the assessment of impacts associated with the proposed upgrade of the Glencairn Hotel. 22 Table 6.2 Criteria used for the assessment of impact significance. _______________________________________ 23 Table 7.1 Results of the risk assessment - CONSTRUCTION _____________________________________________ 34 Table 7.2 Results of the risk assessment – OPERATION ________________________________________________ 36


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1 Introduction

1.1 Background and Approach

The Freshwater Consulting Group (FCG) was approached by SLR Consulting to update a 2003 scoping level impact assessment of the probable impacts associated with upgrading the Glencairn Hotel. The proposed upgrade is located on two erven – Erf 2454 (8 444 m2) on the slopes of the Glencairn Mountain, and erf 235 (820 m2) between the existing hotel and Glencairnvlei, and currently used for parking. The proposal is to develop Erf 2454 into a mixed use residential, retail and commercial development, with Erf 235 formalised and expanded into a parking area and related activities.

Specifically, the terms of reference for the work, and our approach, were as follows:

• Site visit to ensure that the original descriptions of the nature and extent of the affected freshwater ecosystems have not changed. The site was visited on the 21st November 2017. The edge of the Glencairnvlei was delineated using vegetation, topography and hydrology indicators (the soils are too impacted by the pathway and parking area to be used as a reliable indicator of wetland extent) allowing for the mapping (using a hand-held GPS, accurate to approximately 5m) of the outer boundary of the wetland on the site.

• Assess the condition and ecological importance and sensitivity of the affected ecosystems: Water Use authorisation legislation has changed significantly in the last 10 years, and thus it is now necessary to complete a risk assessment matrix for any activity within 500m of a wetland, that may have an impact on the bed, banks and characteristics of that wetland, or on the flow in that wetland (Section 21 (c) and (i) non-consumptive water uses, as covered in GN 509 of August 2016). In order to complete the risk matrix, it is necessary to assess the condition and ecological importance and sensitivity of all affected aquatic ecosystems. To this end, the accepted protocols for the assessment of ecological importance and sensitivity (EIS) and present ecological state (PES) were used in order to undertake an assessment of the affected section of Glencairnvlei. Available background information on the wetland, its catchment and the surrounding area (e.g. CBA and FEPA maps, etc) was consulted, and a summary is provided in this report.

• Complete DWS risk assessment matrix: All probable impacts associated with the proposed activity were assessed using the DWS risk assessment matrix, which examines the severity, spatial scale, duration, frequency and ease of detection of impacts. A combined score of the consequence (sum of severity, spatial scale and duration) and likelihood of each impact allows the assessor to gauge the significance of each impact. The significance level is translated into a risk rating (high, medium or low). If all impacts associated with a development have low risk ratings, then the water use is generally authorised under GN 509 of August 2016, and requires registration only with DWS, while those with a medium to high risk rating are deemed to require a full water use license application.

• Management and monitoring plan: A brief wetland management and monitoring plan was prepared for the affected portion of Glencairnvlei.

• Prepare specialist report for input into a basic assessment report, containing the results of the components described above, and providing an updated impact assessment.


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1.2 Limitations

Mapping was done with a hand-held GPS in order to save time and costs. Accuracy is estimated as being approximately 5m. Delineation of wetlands was done using the indicators described in the DWAF (2005) guidelines for delineation of wetlands and riparian areas, with the exception of soils, which were too disturbed for use. Water quality, invertebrates and algae were not collected as there is sufficient factual and visual information for accurate assessments of PES and EIS for Glencairnvlei.

1.3 Use of this Report

This report reflects the professional opinions of its author. It is the policy of FCG that the full and unedited contents of this report should be presented to the client, and that any summary of the findings should only be produced in consultation with the author.

1.4 Declaration of Independence

This is to confirm that Kate Snaddon, the specialist consultant who is responsible for undertaking this study and preparing this report, is independent, and has no vested interests, financial or otherwise, in the development under consideration.

1.5 Specialist Details

The author of this report is an independent specialist consultant, with 21 years of experience in the field of freshwater ecology, registered with the South African Council for Natural Scientific Professions (registration number 400225/06, Ecological Science).


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2 Description of the affected aquatic ecosystems

2.1 General description of the site

The Glencairn Hotel site is located alongside Glen Road, just off the M4, in the suburb of Glencairn, Cape Town. The site is located in quaternary catchment G22A in the Berg River Water Management Area. The proposed development will impact on two erven, Erf 2454 and Erf 235. Erf 2454 is located on a steep, north-facing slope, which flattens out at the current location of the hotel and its associated commercial buildings. Most of the plot is undeveloped, vegetated with a mix of indigenous and alien plant species, and with numerous emergent sandstone boulders. Extensive clearing of alien plants has occurred on the site, and the species that did occur on the site (hakea, rooikrans, Port Jackson) can be seen on the neighbouring land up the slope. A firebreak, from which vegetation is regularly cleared, runs along the south-eastern boundary of the erf. The plant species on site were described by Roger Jaques of NatureSpace in 2003/2004, as part of the original scoping assessment. No wetlands are located on erf 2454. However, a level shelf has been excavated along the south-western boundary, where a cutoff drain has been constructed to convey surface waters flowing off the mountain away from Erf 2454. The water is directed towards a stormwater drain inlet at the top of the Gardrum Steps.

The upper south-western boundary of Erf 2454 abuts onto private property that has been categorised as a Critical Biodiversity Area in the City of Cape Town’s Biodiversity Network (latest version: 2017).

Erf 235 is essentially a flat plot, currently used for parking space and some commercial activities. The land not tarred for parking is covered by kikuyu grass, which has spread down the slope towards the Glencairnvlei outlet, with a few other planted exotic species (see Photo 1).

The vegetation type historically found on Erf 235 is Cape Flats Dune Strandveld, an endangered vegetation type that occurs on alkaline sands, while further up the slope the vegetation transitions into Peninsula Sandstone Fynbos, a critically endangered type (Rebelo et al., 2006). Some fynbos species have been recorded on the site, primarily on and adjacent to the firebreak (Hughes, 2005; Helme, 2017).

Figure 2.1 Overview of the Glencairn Hotel site, showing its location in relation to Glencairnvlei and the coastline.


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Photo 1 View of the Glencairnvlei channel as it flows towards the M4 road bridge and the sea, showing the encroachment of kikuyu grass down the slopes towards the edge of the vlei, which is vegetated primarily with

Ficinia nodosus and Bolboschoenus maritimus (both sedges).

2.2 Glencairnvlei outlet

Glencairnvlei is fed by the Else River, which rises as a seasonal stream on the slopes between Grootkop and Red Hill. The river is approximately 7km long and drains an 18km2 catchment. Historically, Glencairnvlei was probably a seasonal system, with areas of open water occurring during the wet winter months, and drying up over summer (Day, 2001). The mouth of the vlei would generally have been closed, opening only after heavy rains in winter (Gale, 2000). There is also evidence to suggest that the vlei developed upstream of the railway and road bridges as a result of obstruction of the Else River mouth – the lower Else River would have been a perennial river (Gale, 2000). Today, Glencairnvlei is a perennial wetland, with a weir separating the vlei from its channelised estuarine outlet at the Glen Road bridge, and a causeway in the upper reaches separating the permanent open water section of the vlei from the more seasonally inundated lower reaches. The vlei has been identified as important habitat for a number of waterbirds and semi-aquatic mammals such as otters (Wood, 1992).

Until fairly recently, Glencairnvlei received treated effluent from the Simonstown WWTF, which resulted in increased flows in the lower river during the summer months, and poor water quality. The vlei is still eutrophic, with outbreaks of blue-green algal blooms in the vlei not uncommon (J. Woods, City of Cape Town, pers. comm.). The altered flow regime, poor water quality and control of water height by the weir and the causeway have resulted in the proliferation of dense stands of Typha capensis and Phragmites australis across the whole wetland, with only small patches of open water and other indigenous plant communities (e.g. Psoralea pinnata).

Adjacent to Erf 235, the northern bank of the Glencairnvlei outlet channel slopes away from the wetted edge of the outlet at a fairly gentle gradient, becoming steeper towards the berm that separates the outlet from the M4. The berm is vegetated with typical coastal groundcover species. The southern bank is also steep as it slopes away from the water, and is covered largely by kikuyu grass. A stormwater outlet discharges stormwater from the hotel site and parking area into the outlet channel. The vegetation within the channel includes some bulrush, Typha capensis, close to the Glen Road bridge and a number of sedges,


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predominantly Ficinia nodosus and Bolboscheonus maritimus. Other species include Chrysanthemoides incana, Juncus kraussii, Zantedischia aethiopica (arum lily) and Carpobrotus edulis (sourfig).

Water quality in the outlet was clear and clean at the time of the site visit. Data provided by DWS for the Glencairnvlei outlet show that water quality is generally good, and has been improving over the past 17 years.

Although Glencairnvlei is, strictly speaking, an estuary, it has not been identified as such on the national list of estuaries (Turpie and Clark, 2007), and in fact it has lost much of its estuarine nature due to the presence of the railway line, roads and the weir which have altered tidal exchange in the lower portion of the river. Thus, for this assessment, the ecosystem has been assessed as a wetland, using the methods available for wetland assessments. The Glencairnvlei can be described as a channelled valley-bottom, according to the National Classification System for Inland Aquatic Ecosystems (Ollis et al., 2013).

2.3 Delineation of wetlands

The Department of Water and Sanitation has produced a wetland and riparian zone delineation manual (DWAF, 2005) that describes the indicative characteristics that can be used to distinguish between wetlands or riparian zones and the surrounding terrestrial landscape. These indicators are:

• Vegetation: the presence of plants adapted to or tolerant of saturated soils (hydrophytes); • Soils: the presence of wetland (hydromorphic) soils that display characteristics resulting from

prolonged saturation; • Hydrology: a high water table that results in saturation at or near the surface, leading to anaerobic

conditions developing in the top 50 cm of the soil; • Terrain: the position in the landscape that allows for retention of water and the development of

wetlands.

The methodology outlined in the delineation manual is based on collecting evidence of any or all of these characteristics, and has become widely accepted as the preferred method for wetland identification. Field indicators of these four characteristics are as follows:

• Hydrophytic vegetation – vegetation indicator; • Hydric soils – soil wetness indicator; • Presence of water – hydrology indicator; and • Hydrogeomorphic setting – terrain unit indicator.


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It must be noted that indicators of wetland soils and of wetland hydrology need to be observed within 50 cm of the ground surface for an area to be defined as wetland. In practice, the soil wetness indicator is often used as the primary indicator. At Glencairnvlei, however, the soils adjacent to the vlei outlet are very compacted and transformed, with significant amounts of fill and a pathway. Only the vegetation, topography and hydrology indicators were used to delineate the edge of the vlei outlet, as shown in Figure 2.2.

Figure 2.2 Close up of the site, showing the location of the Glencairnvlei outlet (green polygon) in relation to the hotel site (red boundary). The western boundary of the outlet was delineated using indicators of vegetation,

topography and hydrology.


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3 Assessment of condition and importance of the Glencairnvlei outlet

3.1 Methods

An assessment of the conservation importance of a freshwater ecosystem (watercourse or wetland) should combine assessments of both the current ecological integrity or present ecological state (PES) of the ecosystem and its perceived ecological importance and sensitivity (EIS). The ecological integrity of an ecosystem is defined as its ability to support and maintain a balanced, integrated composition of physico-chemical and habitat characteristics, as well as biotic components on temporal and spatial scales that are comparable to the natural characteristics of ecosystems of the region. The integrity of a system is directly influenced by its current state, and how much the system has been altered from the reference or unimpacted condition. The ecological importance of a freshwater ecosystem is an expression of its importance to the maintenance of ecological diversity (i.e. both species and habitat diversity) and functioning on local and wider scales. Ecological sensitivity (or fragility) refers to the system’s ability to resist disturbance and its capability to recover from disturbance once it has occurred (resilience) (Resh et al., 1988; Milner, 1994). Both abiotic and biotic components of the system are taken into consideration in an assessment of ecological importance and sensitivity. It is strongly biased towards the potential importance and sensitivity of a particular section of a stream or river, as it would be expected under unimpaired conditions.

PES for the wetland was assessed using a Level 1 WET-Health assessment (MacFarlane et al., 2009), and EIS using WET-Ecoservices (Kotze et al., 2008).

3.1.1 PES

The Level 1 WET-Health assessment methodology was used for the rapid assessment of the Present Ecological State (PES) of the hydrology, geomorphology and vegetation of wetlands (MacFarlane et al., 2009). The method is based on the hydrogeomorphic (HGM) approach to wetland classification, providing a PES score for a wetland within each of the three modules, and a combined overall score. The score provides a quantitative measure of the extent, magnitude and intensity of deviation from the reference or unimpacted condition. The score places the wetland in a wetland health category, A – F (see Table 3.1). The wetland is divided into HGM units, and each unit assessed separately.

Table 3.1 Present Ecological State categories (from MacFarlane et al., 2009).

Category Wetland Impact Score

Description

A 0 – 0.9 Unmodified, natural. B 1 – 1.9 Largely natural with few modifications. A slight change in ecosystem processes is

discernible and a small loss of natural habitats and biota may have taken place. C 2 – 3.9 Moderately modified. A moderate change in ecosystem processes and loss of natural

habitats has taken place but the natural habitat remains predominantly intact. D 4 – 5.9 Largely modified. A large change in ecosystem processes and loss of natural habitat and

biota has occurred. E 6 – 7.9 The change in ecosystem processes and loss of natural habitat and biota is great but

some remaining natural habitat features are still recognizable. F 8 - 10 Modifications have reached a critical level and the ecosystem processes have been

modified completely with an almost complete loss of natural habitat and biota.


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3.1.2 EIS

The importance of the wetland was assessed by considering the range of goods and services identified in the Wet-Ecoservices tool (Kotze et al., 2008). These generic services include:

• Flood attenuation • Streamflow regulation • Sediment trapping • Phosphate trapping • Nitrate removal • Toxicant removal • Erosion control • Carbon storage • Maintenance of biodiversity • Water supply for human use • Natural resources • Cultivated foods • Cultural significance • Tourism and recreation • Education and research The outcomes of the Wet-Ecoservices assessment were then used to inform an assessment of the overall importance and sensitivity of the wetland using the Wetland Ecological Importance and Sensitivity (EIS) assessment tool of Rountree et al. (2013). The tool includes an assessment of three suites of importance criteria, namely:

• Traditional ecological importance and sensitivity (biodiversity support, landscape scale importance, and the sensitivity of the wetland to change);

• Hydrological and functional importance (water quality, flood attenuation and sediment trapping ecosystem services that the wetland may provide), and

• Human benefits (subsistence and cultural use of the wetland). Each component was rated, according to the criteria in Table 3.2, below.

Table 3.2 Rating table used to rate ecological importance and sensitivity (EIS) (Rountree et al., 2013).

Rating Explanation None, Rating = 0 Rarely sensitive to changes in water quality/hydrological regime Low, Rating =1 One or a few elements sensitive to changes in water quality/hydrological regime Moderate, Rating =2 Some elements sensitive to changes in water quality/hydrological regime High, Rating =3 Many elements sensitive to changes in water quality/ hydrological regime Very high, Rating =4 Very many elements sensitive to changes in water quality/ hydrological regime

The maximum score for each suite of importance criteria was taken to be the overall EIS category for the wetland, as described in Table 3.3.


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Table 3.3 Ecological Importance and Sensitivity categories for wetlands (Rountree et al., 2013).

Ecological Importance and Sensitivity Categories Range of EIS scores

Very high: Wetlands that are considered ecologically important and sensitive on a national or even international level. The biodiversity of these systems is usually very sensitive to flow and habitat modifications. They play a major role in moderating the quantity and quality of water of major rivers.

>3 and ≤4

High: Wetlands that are considered to be ecologically important and sensitive. The biodiversity of these systems may be sensitive to flow and habitat modifications. They play a role in moderating the quantity and quality of water of major rivers.

>2 and ≤3

Moderate: Wetlands that are considered to be ecologically important and sensitive on a provincial or local scale. The biodiversity of these systems is not usually sensitive to flow and habitat modifications. They play a small role in moderating the quantity and quality of water of major rivers.

>1 and ≤2

Low/marginal: Wetlands that are not ecologically important and sensitive at any scale. The biodiversity of these systems is ubiquitous and not sensitive to flow and habitat modifications. They play an insignificant role in moderating the quantity and quality of water of major rivers.

>0 and ≤1

3.2 Results

3.2.1 PES

The current ecological condition of the Glencairnvlei has been significantly impacted by alterations to the natural hydrological regime of the ecosystem. This is due to the impoundment and abstraction of water in the upper Else River catchment (Kleinplaas and Lewis Gay dams), with smaller weirs and causeways located along the length of the remaining river. The shape and alignment of the wetland channels have also been altered through limited infilling for the construction of bridges over the river, and encroachment of developed areas on either side of the vlei. Flow obstructions and abstraction also lead to the loss of flushing flows through the system, and the build-up of sediments. The vegetation in the vlei has responded to these changes in hydrology and geomorphology, leading to establishment of beds of reeds and bulrush, instead of a more diverse wetland community. These existing impacts are reflected by the PES scores calculated for Glencairnvlei, giving the wetland an overall wetland PES of D – largely modified (Table 3.4).

Table 3.4 PES scores for Glencairnvlei, following the Wet-Health protocol of MacFarlane et al. (2009).

HGM Unit Area Hydrology Geomorphology Vegetation

Score Category Score Category Score Category

Channelled valley-bottom wetland 10.6 hectares 7.0 E 2.2 C 3.0 C

Overall Wetland Impact Score 4.49

Wetland PES D

3.2.2 EIS

The overall ecological importance and sensitivity of Glencairnvlei is high (score of 3), while the hydrological/functional importance is moderate and the human use rating is low (Table 3.5). The latter is due to the fact that the vlei does not provide services of direct benefit to the surrounding communities,


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such as potable or irrigation water, harvestable resources (such as reeds and restios, fish etc) or crops. The vlei does, however, provide an important feeding / breeding / migration node, in an increasingly urban area. While the species that the vlei supports are not necessarily rare or endangered, these species are important in terms of the overall biodiversity of the ecosystem. In addition, the vlei is sensitive to changes in low flows and water quality.

Table 3.5 Wetland EIS for Glencairnvlei.

Ecological Importance Score (0-4)

Biodiversity support 2.33 Presence of Red Data species 2.00

Populations of unique species 2.00

Migration/breeding/feeding sites 3.00

Landscape scale 3.00 Protection status of the wetland 4.00

Protection status of the vegetation type 3.00

Regional context of the ecological integrity 2.00

Size and scarcity of the wetland type/s present 3.00

Diversity of habitat types 3.00

Sensitivity of the wetland 2.33 Sensitivity to changes in floods 1.00

Sensitivity to changes in low flows/dry season 3.00

Sensitivity to changes in water quality 3.00

Ecological Importance & Sensitivity 3.00 Hydrological/Functional Importance 1.93 Direct Human Benefits 0.98

3.3 Buffer determination

The buffer width tool developed by MacFarlane et al. (2014) was used to determine an appropriate buffer for Glencairnvlei, for both the construction and operation phases of the project. The assessment is based on the PES and EIS of the wetland, and the quality of the buffer during both phases of the project. It was assumed that the current vegetation (grass, sedges, some shrubs) would be representative of the buffers for both phases, unless the actual removal of vegetation and soils is expected on Erf 235. The density of vegetation plays a major role in determining the effectiveness of a buffer – a well-vegetated buffer, with a high basal cover (such as grass or sedges) is the most effective buffer, due to the ability of the plants and their roots to trap sediments, toxins and other pollutants before they reach the wetland or watercourse.

The results of the buffer determination are presented in Table 3.6.


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Table 3.6 Results of the buffer width determination for Glencairnvlei outlet. The determination was done using the tool of MacFarlane et al. (2014).

Buffer attributes Description Slope of the buffer Moderate(10.1 - 20%) Vegetation characteristics (Construction phase)

High: Dense vegetation, with good basal cover (e.g. low growing shrubs, restios, sedges)

Vegetation characteristics (Operational phase)

High: Dense vegetation, with good basal cover e.g. low growing shrubs, restios, sedges)

Soil permeability High: Deep well-drained soils (e.g. sand and loamy sand).

Topography of the buffer zone Uniform topography: Smooth topography with no concentrated flow paths anticipated.

Construction Phase Buffer 15 m

Operational Phase Buffer 15 m

The recommended minimum buffer for Glencairnvlei is 15m measured from the edge of the outlet wetland, for both the construction and operational phases, assuming that the vegetation cover currently covering the slope between the parking area and the outlet channel is revegetated with appropriate low-growing vegetation, as opposed to kikuyu grass.


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4 Legislation and guidelines governing the conservation and management of rivers and wetlands

4.1 National Environmental Management Act (Act 107 of 1998 as amended by Act 62 of 2008)

The National Environmental Management Act of 2008 (NEMA), outlines measures that….”prevent pollution and ecological degradation; promote conservation; and secure ecologically sustainable development and use of natural resources while promoting justifiable economic and social development.”

Of particular relevance to this assessment is Chapter 1(4r), which states that sensitive, vulnerable, highly dynamic or stressed ecosystems, such as coastal shores, estuaries, wetlands, and similar systems require specific attention in management and planning procedures, especially where they are subject to significant human resource usage and development pressure.

Section 24 of NEMA requires that the potential impact on the environment, socio-economic conditions and cultural heritage of activities that require authorisation or permission by law, must be considered, investigated and assessed prior to implementation, and reported to the relevant regulatory authority.

4.2 Environmental Impact Assessment regulations (2014), as amended

These regulations identify activities deemed to have a potentially detrimental effect on natural ecosystems, including aquatic ecosystems, and outline the requirements and timeframe for approval of development applications. Different sorts of activities are listed as environmental triggers that determine different levels of impact assessment and planning required. The regulations detail the procedure to be followed for a basic or full environmental impact assessment.

4.3 Conservation of Agricultural Resources Act (Act 43 of 1983)

Key aspects include legislation that allows for:

Section 6: Prescription of control measures relating to the utilisation and protection of vleis, marshes, water sponges and water courses. These measures are described in regulations promulgated in terms of the Act, as follows:

Regulation 7(1): Subject to the Water Act of 1956 (since amended to the Water Act 36 of 1998), no land user shall utilise the vegetation of a vlei, marsh or water sponge or within the flood area of a water course or within 10 m horizontally outside such flood area in a manner that causes or may cause the deterioration or damage to the natural agricultural resources.

Regulation 7(3) and (4): Unless written permission is obtained, no land user may drain or cultivate any vlei, marsh or water sponge or cultivate any land within the flood area or 10 m outside this area (unless already under cultivation).

4.4 National Environmental Management: Biodiversity Act (Act 10 of 2004)

To provide for the management and conservation of South Africa’s biodiversity within the framework of the National Environmental Management Act of 1998; the protection of species and ecosystems that warrant national protection; the sustainable use of indigenous biological resources; the fair and equitable sharing of benefits arising from bio-prospecting involving indigenous biological resources; the establishment and functions of a South African National Biodiversity Institute.


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4.5 Cape Nature Conservation Ordinance (Ordinance 19 of 1974; amended in 2000)

This ordinance provides measures to protect the natural flora and fauna, as well as listing nature reserves in the Western Cape that are managed by the Western Cape Nature Conservation Board (WCNCB). This ordinance, with the Western Cape Nature Conservation Board Act of 1998 was amended in 2000 to become the Nature Conservation Laws Amendment Act. Lists of endangered flora and fauna can be found in this act.

4.6 National Water Act (1998)

The main regulatory requirements with regards to aquatic features relates to the National Water Act No. 36 of 1998 (NWA). The NWA regulates 11 water uses that require authorisation, as follows:

a. Taking water from a water resource;

b. Storing water;

c. Impeding or diverting the flow of water in a watercourse;

d. Engaging in a stream flow reduction activity;

e. Engaging in a controlled activity identified and declared as such in terms of the Act;

f. Discharging waste or water containing waste into a water resource through a pipe, canal, sewer, sea outfall or other conduit;

g. Disposing of waste in a manner which may detrimentally impact on a water resource;

h. Disposing in any manner of water which contains waste from, or which has been heated in, any industrial or power generation process;

i. Altering the bed, banks, course or characteristics of a watercourse;

j. Removing, discharging or disposing of water found underground if it is necessary for the efficient continuation of an activity or for the safety of people; and

k. Using water for recreational purposes.

The construction of river crossings and the laying of pipes over a watercourse or wetland can lead to changes in flow in (Section 21 (c)) or alterations to the bed and banks/characteristics of (Section 21 (i)) the affected watercourse, and so a water use authorisation must be obtained for these specific activities. Should stormwater be discharged into seeps or streams, this is generally authorised (but requires registration) up to 2000 m3 per day (Section 21 (f)). Volumes higher than this will be subject to a full water use licence application.

DWA have issued a number of General Authorisations (GA) in terms of Section 39 of the National Water Act. A water use may be generally authorised if it falls within a specific threshold or area. The GA of the 26th August 2016 (Government Notice 509 of 2016) provides the limits and conditions of Section 21 (c) and (i) water uses that may be generally authorised, and defines the regulated zone within which the GA applies. The draft GA of April 2012 (Government Notice 288 of 2012) covers the conditions for taking (Section 21 (a)) and storing (Section 21 (b)) water. These conditions apply to storage of water that exceeds 2000 m3 (in the case of catchment G22). This GA states:

“A person who owns or lawfully occupies a property or piece of communal land may, in terms of this authorisation, on the property or piece of communal land occupied store water not containing waste up to the maximum volume given in Table 1: Surface water abstraction and storage volumes in Appendix A for


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the catchment in which the stored water is taken” … (2000 m3 for catchment G22)… “subject to the following specific conditions and the general conditions in this notice.

Specific conditions for storing of water:

• Water stored in terms of this authorisation may only be stored off-channel. • Retaining structures for the storing of water in terms of this authorisation that are constructed after

this authorisation comes into effect must have outlet works that enable the full storage volume to be released within 30 days.

• Up to the maximum volume of water given for the resource in Table 1: Surface Water Abstraction Rates and Storage Volumes in Appendix A may be stored in terms of this authorisation for use on one property or per person in communal land.

General conditions of this GA include:

• Water stored must be used efficiently, and the water user must investigate and use all reasonable water conservation measures.

• The storage of more than 10 000 m3 on one property must be registered with DWS.

4.7 Western Cape Provincial Spatial Development Framework (2014)

Policies regarding the protection of biodiversity and ecosystem services in the Western Cape are:

• The Western Cape’s Critical Biodiversity Area (CBA) mapping, which CapeNature are currently updating and refining, together with the draft priority climate change adaption corridors, comprise the spatial extent of the Western Cape’s biodiversity network. This must inform spatial planning and land use management decisions throughout the province.

• Using the latest available CBA mapping as a primary informant, regional, district and municipal SDFs must delineate Spatial Planning Categories (SPCs) that reflect suitable land use activities in the different CBA categories.

• To complement CapeNature’s protected area expansion strategy and their Stewardship programme, SDFs should highlight priority areas outside the protected area network that are critical for the achievement of the province’s conservation targets.

Policies regarding the management, repair and optimisation of inland water resources are:

• Given current water deficits, which will be accentuated by climate change, a ‘water wise’ planning and design approach in the W Cape’s built environment is to be mainstreamed.

• Rehabilitation of degraded water systems is a complex inter-disciplinary intervention requiring built environment upgrading (i.e. infrastructure and the built fabric), improved farming practises, as well as the involvement of diverse stakeholders.

• Introduce and retrofit appropriate levels of water and sanitation systems technologies in informal settlements and formal neighbourhoods with backyard shacks as a priority.

• An overarching approach to water demand management is to be adopted – firstly efficiencies must be maximised, storage capacity sustainably optimised and ground water extraction sustainably optimised, with the last resort option of desalination being explored, if necessary.

• Protection and rehabilitation of river systems and high yielding groundwater recharge areas, particularly in areas of intensive land use (i.e. agricultural use, industry, mining and settlement interactions) should be prioritised.

• Regional Plans to be developed for Water Management Areas to ensure clear linkages and interdependencies between the natural resource base (including water resources) and the socio-economic development of the region are understood and addressed.


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• Agricultural water demand management programmes to be developed with an emphasis on the Breede Valley and Oliphants / Doorn agricultural areas. Industrial water demand management programmes to be developed with an emphasis on Saldanha, Southern Cape and Cape Town.

• Settlement water demand management programmes to be developed with an emphasis on the Cape Town functional region.

• Government facilities (inclusive of education, health and public works facilities) to lead in implementing effective and efficient water demand management programmes.

• Continue with programmes (such as Working for Water) which reduce the presence of alien vegetation along river systems.

4.8 Biodiversity Spatial Plans

The Western Cape Biodiversity Spatial Plan (WCBSP, 2017) is the product of a systematic biodiversity planning assessment that delineates Critical Biodiversity Areas (CBAs) and Ecological Support Areas (ESAs) which require safeguarding to ensure the continued existence and functioning of species and ecosystems, including the delivery of ecosystem services, across terrestrial and freshwater realms. These spatial priorities are used to inform sustainable development in the Western Cape Province. This product replaces all previous systematic biodiversity planning products and sector plans with updated layers and features.

The Biodiversity Network is a spatial biodiversity plan developed at a finer scale for the City of Cape Town, starting in 2002, with the most recent analysis and update being done in 2016. The Network maps both terrestrial and aquatic CBAs, ESAs and other Natural areas, and provides the biodiversity priorities at the local, municipal level.


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5 Description of proposed development The developer proposes to redevelop the existing hotel (originally built in 1904) and to develop the remainder of Erf 2454 to a combination of residential, retail and office development, as follows:

• A new rear hotel wing and conference centre would comprise the following: o Six self-catering suites (30 m² each); o Six en-suite hotel rooms (30 m² each); o A conference centre / function venue around a swimming pool courtyard, and o Four retail kiosks in front of the hotel (20 m² each).

• Ten luxury apartments, comprising: o Four two-bedroom apartments (146 m² each) on terraces with a double garage each, and o Six two-bedroom apartments (98 m² each) on terraces with a single garage.

• Six apartments and a lifestyle square, comprising: o Four two-bedroom apartments (126 m² each); o Two two-bedroom apartments (110 m² each) overlooking the lifestyle square; o Six to eight retail commercial units (total footprint 375 m²) around a reduced square with a

proposed focus on lifestyle-oriented activities (adventure, tourism, children, etc.); o Four to eight small offices for centre management, etc. (total 88 m²), and o Sixteen covered parking bays.

• Five single residential units, each unit comprising a four-bedroom house (250 m²) and flatlet and double garage located on an individual erf, ranging in size between approximately 559 m² and 655 m².

Included in the proposal is the landscaping of the banks of the Glencairnvlei outlet, by reshaping banks, removing kikuyu, and possibly constructing a boardwalk to the beach under the road bridge.

5.1 Roads

The applicant proposes to realign a portion of Glen Road in order to provide a single access road on the north-western boundary of Erf 2454 from Gardrum Steps to the back of the hotel. This road would service the new hotel rooms, 10 self-catering units and the five single residential erven. In front of the hotel, Erf 235 would be formalised and expanded into a 68-bay (34 on either side of Glen Road) parking area for the hotel and related activities.

All roads will be a combination of paving and premixed surfaces, with barrier kerbs on either side due to the steepness of the site. All new parking areas will be constructed using permeable surfaces, such as grass blocks.

5.2 Water and Sewerage

The existing hotel is connected to a 200 mm sewer main. The proposed development would require an additional 160 mm main pipe with 100 mm house connections gravitating to the existing sewer main. A new water reticulation system would be provided in order to link the development with a bulk combination water meter, and each residence will be fitted with an individual meter.


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It is recommended that all roofs be equipped with guttering leading into rainwater tanks, in order to store and use rainwater for irrigation and possibly for augmenting bulk water supply for use within the hotel and residential units for flushing toilets.

5.3 Stormwater

A cut-off drain is located at the top of the site along the western boundary (in the firebreak), which diverts water away from Erf 2454 towards the Gardrum Steps. There are currently no facilities for stormwater storage, and currently all stormwater running off the hotel site is conveyed into the Glencairnvlei outlet channel via a stormwater pipe under the parking area downstream of the hotel.

Unlined stormwater conveyance channels are proposed for within the development and alongside roads, in order to reduce the quantity of water exiting the site, or needing to be stored. Sand and grease traps located at the north-eastern and south-eastern corners of the development are proposed in order to improve the quality of stormwater before it enters the vlei.

An alternative may be to construct one or two small vegetated detention ponds at the edge of the Glencairnvlei, in order to allow settlement of sediments and pollutants and infiltration of water into the ground, before discharging into the channel outlet under the M4 road bridge.

The space available for construction of stormwater detention ponds between the proposed parking bays and the vlei is very limited. It may be preferable to construct underground storage for a proportion of the stormwater that will accumulate at the lower end of the site. This could then be pumped back into the development for irrigation or for use in the hotel of residential units. The remaining proportion of the stormwater can be allowed to flow as sheet flow onto the banks of the Glencairnvlei outlet. This can be achieved through the use of spreaders and planted verges that would absorb the runoff at the edge of the parking area.


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Figure 5.1 Proposed re-development of the Glencairn Hotel (November 2017).


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6 Impact Assessment 6.1 Protocol for the assessment of impacts

The evaluation of impacts was done using the criteria stipulated in the EIA Regulations published by the Department of Environmental Affairs according to the Environmental Conservation Act (1979), and listed in Table 6.1. Table 6.2 provides the criteria used for the assessment of significance of the impacts.

Table 6.1 Criteria used for the assessment of impacts associated with the proposed upgrade of the Glencairn Hotel.

Criterion Description a) Nature and

status of impact Define or describe the type of effect (negative, positive or neutral) that a proposed activity would have on the environment. This description includes what is to be affected and how.

b) Extent Describe whether the impact occurs on a scale limited to the local area (i.e. limited to within 10 km of the activity), regional (Western Cape), national (South Africa) or international.

c) Duration Predict whether the lifespan of the impact will be short term (0 to 5 years); medium term (5 to 15 years); long term (i.e. beyond the operational phase but not permanently), or permanent (i.e. mitigation through natural processes or human intervention will not occur in such a way or in such time span that the impact can be considered transient).

d) Intensity Describe whether the intensity (magnitude/size) of the impact is high (environmental functions and processes are altered in such a way that they temporarily or permanently cease); medium (environmental functions are altered but continue in a modified manner); low (environmental functions are altered but continue in a slightly modified manner) or zero to very low (no functions and processes are affected). The specialist study must attempt to quantify the magnitude of impacts, with the rationale explained.

e) Probability Describe the probability of the impact actually occurring as definite (impact will occur regardless of mitigations), highly probable (most likely), probable (distinct possibility), or improbable (low likelihood).

f) Reversibility The degree to which an impact can be reversed, from fully reversible, to partly reversible to irreversible.

g) Irreplaceable loss of resources

The degree to which resources will be irreplaceably lost as a result of the activity – low, medium and high.

h) Cumulative effect

The past, current and reasonably foreseeable future impact of an activity, considered together with the impact of activities associated with that activity, that in itself may not be significant, but may become significant when added to the existing and reasonably foreseeable impacts eventuating from similar or diverse activities

i) Significance The significance of impacts shall be assessed with and without mitigation (see also Table 6.2). The significance of identified impacts on components of the affected environment shall be described as: - high: where the impact could have a no-go implication for the development or a component of the development, regardless of any possible mitigation. - medium: where the impact could have an influence on the environment which will require modification of the development design or alternative mitigation/s. - low: where the impact will have a slight influence on the environment, but this can be accommodated without modification to the development design. - negligible: where the impact will not have an influence on the environment.

j) Degree to which an impact can be mitigated

The impact can be fully mitigated, partly mitigated or not mitigated.

k) Degree of confidence

Confidence with which significance assessment is done.


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Table 6.2 Criteria used for the assessment of impact significance.

Significance ratings Level of criteria required

Very high

Impacts could be EITHER: of high intensity at a national or regional level and endure permanently or in the long term; OR of high intensity at a national level in the medium term; OR of medium intensity at a national level and endure permanently or in the long term.

High

Impacts could be EITHER: of high intensity at a regional level and endure in the medium term; OR of high intensity at a national level in the short term; OR of medium intensity at a national level in the medium term; OR of low intensity at a national level in the long term; OR of high intensity at a local level in the long term; OR of medium intensity at a regional level in the long term.

Medium

Impacts could be EITHER: of high intensity at a local level and endure in the medium term; OR of medium intensity at a regional level in the medium term; OR of high intensity at a regional level in the short term; OR of medium intensity at a national level in the short term; OR of medium intensity at a local level in the long term; OR of low intensity at a national level in the medium term; OR of low intensity at a regional level in the long term.

Low

Impacts could be EITHER: of low intensity at a regional level and endure in the medium term; OR of low intensity at a national level in the short term; OR of high intensity at a local level and endure in the short term; OR of medium intensity at a regional level in the short term; OR of low intensity at a local level in the long term; OR of medium intensity at a local level and endure in the medium term.

Very low

Impacts could be EITHER: of low intensity at a local level and endure in the medium term; OR of low intensity at a regional level and endure in the short term; OR of low to medium intensity at a local level and endure in the short term.

Neutral Zero intensity with any combination of extent and duration.

6.2 Description of probable impacts and mitigation measures

6.2.1 Layout

Impact Mitigation measures

Loss of open space –development of the site will lead to the loss of some open space between the Glencairn Mountain and the vlei. The connectivity between the wetland and surrounding terrain is important, and fragmentation of this connectivity could lead to deterioration in habitat condition. This impact will not lead to direct wetland loss, but rather a lowered ecological state.

o It is recommended that a 15 m buffer be established, measured from the edge of the Glencairnvlei outlet boundary, as mapped in Figure 2.2. All buildings and infrastructure should be located outside of the buffer.


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6.2.2 Construction phase

The mitigation measures provided below should be incorporated into a construction Environmental Management Plan (EMP), and audited throughout the construction process. An adequately qualified independent environmental control officer (ECO) must be appointed before construction begins. The CEMP must also include recommendations regarding the method statements required by the ECO.


Storage of building materials (sand, soil, bricks etc) in sensitive areas such as close to the vlei buffer – this would damage the soil structure, and would destroy or shade out plants growing in and around the wetland. Dump areas frequently lead to the compaction of soils, which can influence re-growth of plants.

o Ensure that all building materials are stored at least 15m away from the edge of the wetland, as demarcated prior to construction. Storage areas should be bunded adequately to prevent contaminated runoff from entering the wetland.

o Materials should be stored in piles that do not exceed 1.5m in height and should be protected from the wind (such as shadecloth fences), to prevent spread of fine materials across the site.

o All areas that are impacted by the storage of materials must be ripped and re-planted after construction is complete.

Pollution of the wetland through leakage of fuels, oils, etc. from construction machinery.

o Construction close to the wetland (i.e. on Erf 235) should preferably take place during the dry season, to reduce the risks of contamination of the ecosystem through rainfall and runoff.

o No mixing of concrete may occur close to (less than 15m) the wetlands.

o Machinery prone to oil or fuel leakage must be located at least 15m away from the edge of the wetland, and the area adequately bunded in order to contain leakages.

o Water pumps and cement mixers shall have drip trays to contain oil and fuel leaks – these must be cleaned regularly.

o Suitable toilet and wash facilities must be provided to avoid the use of sensitive areas for these activities. These service areas must be maintained, and toilets emptied on at least a weekly basis.

Destruction or deterioration of wetland habitat as a result of foot and vehicular traffic

o Pathways and access roads must be routed around the wetland and its buffer.

o Sensitive areas must clearly be demarcated and fenced off (using temporary fencing and danger tape) before any construction work or site preparation begins. These are no-go areas during the construction process.

o All impacted areas must be ripped and re-planted after construction, to the satisfaction


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Impact Mitigation measures of the ECO.

Disturbance of freshwater fauna and flora – the presence of construction teams and their machinery will lead to noise and light pollution in the area, which will disturb aquatic and terrestrial fauna and flora.

o The construction sites and pathways must avoid sensitive areas. If lights are used, these must be directed away from the wetland.

o Sensitive areas (i.e. the edges of the buffer around the vlei) must clearly be demarcated and fenced off (using temporary fencing and danger tape) before any construction work or site preparation begins. These are no-go areas during the construction process.

Input of sediments – construction activities on the steep slopes on the site will lead to increased input of mobile sediments, especially during the wet winter months.

o Construction close to the wetland (i.e. on Erf 235) should take place only during the dry season, to reduce the risks of contamination through rainfall, runoff and erosion.

o Special care should be taken around storm and heavy rain events. The site should be inspected for erosion damage at these times.

o If construction areas are to be pumped of water (e.g. after rains), this water must first be pumped into a settlement area, and not directly into the wetland.

Introduction and spread of alien invasives – top material brought onto the site, for filling and landscaping can lead to the introduction of alien or invasive seedbanks.

o Top material must be sourced from a reliable source, and checked for IAP seedlings before being used.

o Constant monitoring of the construction site by the Site Engineer and ECO must occur, and all alien plant species removed from or destroyed on the site.

6.2.3 Operational Phase


Decrease in water quality A decrease in water quality can follow from discharge of residential stormwater into natural areas. Residential stormwater is generally not heavily polluted, but does contain oil and petrol and, of greater significance, nutrients such as nitrates and phosphates. These nutrients can lead to the proliferation of algae in areas of standing water, which can be problematic and unsightly. This impact is likely to impact both the site area and any downstream areas should this polluted water leave the property.

o No hardened surfaces or stormwater detention ponds should be constructed within the recommended 15m buffer, measured from the edge of the vlei outlet. This will allow runoff to flow over some distance before discharging into the vlei itself.

o Roads, verges and parking areas must be constructed with permeable materials, such as permeable paving, grass blocks, interlocking blocks, etc.

o All roofs must have adequate guttering that leads into rainwater tanks, for storage of water after rainfall. This water can be used for irrigation, or be fed into a dual reticulation system whereby recycled grey water can be


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Impact Mitigation measures mixed with rainwater and used for flushing of toilets.

o All remaining impermeable areas should be associated (where possible) with vegetated filter strips (broad, sloped vegetated areas that accept shallow runoff from hardened surfaces), bioswales (landscaped areas that are designed to remove silt and a number of pollutants from runoff, through ensuring that water flows slowly along these gently sloping (<6% slope) features, often planted with grass or other plant species, mulch or riprap), and / or bio-retention systems (vegetated areas where runoff is filtered through a filter media layer, e.g. sand, as it percolates downwards), all of which are designed to reduce the quantity of runoff leaving a hardened surface and entering the stormwater system.

Changes in water inputs and flow patterns The hardened surfaces of the development will lead to a slight increase in stormwater runoff generated by the site, thus increasing pre-development volumes. Discharge of stormwater into Glencairnvlei will have a slight impact on the hydrology of this part of the vlei. It would be achievable to reduce the amount of post-development runoff to a negligible amount through the implementation of some mechanisms, such as rainwater tanks and recycling of stormwater for use within the development. In the current water crisis, this approach makes the most sense, and would reduce this impact to negligible significance.

o Effort should be made to minimise the hardening of surfaces. Natural areas, gardens and road verges are areas where water can filter into the ground.

o Roads, verges and parking areas must be constructed with permeable materials, such as permeable paving, grass blocks, interlocking blocks, etc.

o All roofs must have adequate guttering that leads into rainwater tanks, for storage of water after rainfall. This water can be used for irrigation, or be fed into a dual reticulation system whereby recycled grey water can be mixed with rainwater and used for flushing of toilets.

o All remaining impermeable areas should be associated (where possible) with vegetated filter strips (broad, sloped vegetated areas that accept shallow runoff from hardened surfaces), bioswales (landscaped areas that are designed to remove silt and a number of pollutants from runoff, through ensuring that water flows slowly along these gently sloping (<6% slope) features, often planted with grass or other plant species, mulch or riprap), and / or bio-retention systems (vegetated areas where runoff is filtered through a filter media layer, e.g. sand, as it percolates downwards), all of which are designed to reduce the quantity of runoff leaving a hardened surface and entering the stormwater system.

o Stormwater should not be conveyed directly into


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Impact Mitigation measures the wetland but must flow along unlined swales, permeable areas, bioswales and/or unlined detention ponds.

o Stormwater could be recycled for use within the development by pumping from a storage point (underground storage or a small detention pond in the parking area) at the lowest level (such as within the parking area) back up the slope for use for irrigation or even inside the buildings for flushing of toilets.

Disturbance of fauna and flora Disturbance is likely as a result of the proximity of houses to the wetlands, including noise, light, trampling, domestic pets, etc.

o Lighting should face away from the wetland. o Domestic pets should be discouraged from

entering the wetland and its buffer, through the wise use of fencing and gates.

Spread and establishment of alien and invasive plants Seeds and seedlings may be transported onto site during landscaping. Alien vegetation is also well adapted to establishing on previously disturbed soils and road verges.

o Landscaping must be kept to a minimum. Gardens should rather be natural areas, where the locally indigenous vegetation is allowed to grow.

o No kikuyu grass may be allowed anywhere on site. Alternative grass species such as Cynodon dactylon, or Paspalum vaginatum must be used.

o The spread of alien plant species into all natural areas must be prevented and monitored.

o Road verges must be monitored for alien species, especially grasses.

6.2.4 Cumulative impacts

The cumulative impacts of most concern in this area are:

• Loss of open space; • Deterioration in water quality, and • Changes to the hydrology of the vlei, which has already been heavily transformed due to impacts on

hydrology.

6.3 Results of assessment of impacts

The following tables provide assessments of the impacts associated with the proposed development, using the criteria outlined in Section 6.1.

6.3.1 Layout Potential impacts on the freshwater

ecosystems: Development proposal

Nature of impact Loss of open space within the broader sub-catchment Status of impact Negative Extent of impact Local – only the sub-catchment Duration of impact Permanent – unless the hotel development is removed.


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Potential impacts on the freshwater ecosystems: Development proposal

Intensity of impact Low – the surrounding catchment is already highly developed, and so the likelihood of there being significant movement of fauna and flora through the site is low.

Confidence of assessment Moderate Probability of occurrence Probable – if there is movement of flora and fauna through the site,

these will be impacted by the development. Degree to which the impact can be reversed Fully reversible – should the development be removed, and there has

not been significant development in the area, connectivity will be regained.

Degree to which the impact may cause irreplaceable loss of resources

Low – see above

Cumulative effect prior to mitigation Medium – complete development of the sub-catchment will have a deleterious effect on local movement of flora and fauna, from the mountains to the sea.

Significance rating of impact prior to mitigation

Low

Degree to which the impact can be mitigated Not mitigated Cumulative effect post mitigation Medium Significance rating of impact after mitigation Low

6.3.2 Construction Phase Potential impacts on the freshwater


Nature of impact Storage of building materials Status of impact Negative Extent of impact Local Duration of impact Short-term (during the construction phase) Intensity of impact Low – this takes into account the fact that the soils on the site are

already transformed) Confidence of assessment High Probability of occurrence Improbable – it is unlikely that materials will be stored close to the

more sensitive parts of the site, as there is sufficient space on site to ensure that this does not occur.

Degree to which the impact can be reversed Fully reversible Degree to which the impact may cause irreplaceable loss of resources

Low

Cumulative effect prior to mitigation Low Significance rating of impact prior to mitigation

Low

Degree to which the impact can be mitigated Fully mitigated Cumulative effect post mitigation Very low Significance rating of impact after mitigation Very low


Nature of impact Pollution of the wetland through leakage of fuels, oils, etc. from construction machinery.

Status of impact Negative Extent of impact Local – but including downstream impacts (i.e. the coastline) Duration of impact Short-term (during the construction phase – recovery may take some

time but unlikely to exceed 5 years) Intensity of impact Medium – should a leak or seepage of pollutants occur, this will have

an impact on the fauna and flora occupying the Glencairnvlei outlet Confidence of assessment Medium


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Probability of occurrence Probable Degree to which the impact can be reversed Fully reversible Degree to which the impact may cause irreplaceable loss of resources

Low

Cumulative effect prior to mitigation Medium Significance rating of impact prior to mitigation

Medium

Degree to which the impact can be mitigated Fully mitigated Cumulative effect post mitigation Low Significance rating of impact after mitigation Very low


Nature of impact Destruction or deterioration of wetland habitat as a result of foot and vehicular traffic

Status of impact Negative Extent of impact Local Duration of impact Short-term (during the construction phase) Intensity of impact Low Confidence of assessment High Probability of occurrence Improbable – access across and into the wetland should not be

required, and the area can be avoided by the construction teams. Degree to which the impact can be reversed Fully reversible Degree to which the impact may cause irreplaceable loss of resources

Low

Cumulative effect prior to mitigation Low Significance rating of impact prior to mitigation

Low

Degree to which the impact can be mitigated Fully mitigated – especially through demarcating the edge of the wetland, and making this a no-go area during construction

Cumulative effect post mitigation Very low Significance rating of impact after mitigation Very low


Nature of impact Disturbance of freshwater fauna and flora Status of impact Negative Extent of impact Local Duration of impact Short-term (during the construction phase) Intensity of impact Low – the surrounding area is already highly urbanised, so it is most

likely that fauna already avoid the area Confidence of assessment Medium Probability of occurrence Probable – the construction phase will be associated with an increase

in noise and disturbance, which will impact on fauna and flora occurring on and around the site.

Degree to which the impact can be reversed Partly reversible – once the disturbance is present, this may lead to the loss of fauna and flora that would occur or pass through the site.

Degree to which the impact may cause irreplaceable loss of resources

Low


Low

Degree to which the impact can be mitigated Partly mitigated Cumulative effect post mitigation Low


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Significance rating of impact after mitigation Very low


Nature of impact Input of sediments Status of impact Negative Extent of impact Local – but extending downstream, i.e. to the coastline Duration of impact Short-term (during the construction phase, but recovery may take

some time) Intensity of impact Medium – sedimentation will have serious consequences for the

wetland habitat, fauna and flora through smothering, etc Confidence of assessment High Probability of occurrence Highly probable, especially when work commences on Erf 235 Degree to which the impact can be reversed Partly reversible Degree to which the impact may cause irreplaceable loss of resources

Medium


Medium



Nature of impact Introduction and spread of alien invasives Status of impact Negative Extent of impact Local Duration of impact Short-term (during the construction phase) Intensity of impact Medium – alien and/or invasive plant species are excellent colonisers

of disturbed areas, so this is often a problem on construction sites. Confidence of assessment High Probability of occurrence Probable Degree to which the impact can be reversed Fully reversible Degree to which the impact may cause irreplaceable loss of resources

Low

Cumulative effect prior to mitigation High Significance rating of impact prior to mitigation

Low



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6.3.3 Operational Phase Potential impacts on the freshwater


Nature of impact Decrease in water quality Status of impact Negative Extent of impact Local – extending downstream to the coastline Duration of impact Long-term Intensity of impact Low to medium Confidence of assessment Medium Probability of occurrence Probable Degree to which the impact can be reversed Partly reversible – pollution impacts may have some residual impact

in the long-term Degree to which the impact may cause irreplaceable loss of resources

Low to medium


Low to medium

Degree to which the impact can be mitigated Partly mitigated Cumulative effect post mitigation Low to medium Significance rating of impact after mitigation Low


Nature of impact Changes in water inputs and flow patterns Status of impact Negative Extent of impact Local Duration of impact Long-term Intensity of impact Medium Confidence of assessment High Probability of occurrence Definite Degree to which the impact can be reversed Partly reversible – a change to hydrology will have a significant impact

on the wetland, and recovery may leave some residual impact. Degree to which the impact may cause irreplaceable loss of resources

Low


Low to medium

Degree to which the impact can be mitigated Partly mitigated Cumulative effect post mitigation Low Significance rating of impact after mitigation Low


Nature of impact Disturbance of fauna and flora Status of impact Negative Extent of impact Local Duration of impact Long-term Intensity of impact Low Confidence of assessment Medium Probability of occurrence Probable Degree to which the impact can be reversed Partly reversible Degree to which the impact may cause irreplaceable loss of resources

Low

Cumulative effect prior to mitigation Medium Significance rating of impact prior to Low


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mitigation Degree to which the impact can be mitigated Partly mitigated Cumulative effect post mitigation Low Significance rating of impact after mitigation Very low


Nature of impact Spread and establishment of alien and invasive plants Status of impact Negative Extent of impact Local Duration of impact Long-term Intensity of impact Medium – alien and/or invasive plant species are excellent colonisers

of disturbed areas and road verges, so this needs constant vigilance. Confidence of assessment High Probability of occurrence Probable Degree to which the impact can be reversed Fully reversible Degree to which the impact may cause irreplaceable loss of resources

Low


Low



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7 Water use authorisation The proposed development takes place within 500m of Glencairnvlei, thus triggering the need for a non-consumptive water use authorisation (see Section 4.6). Non-consumptive water uses may impact on the integrity and function of water resources and the overall quality of the resource and therefore must be authorised as a water use by the DWS. The process to be followed to obtain authorisation for these categories of water use is different for each water use, and relates to the risk associated with the water use.

The General Authorisation (GA) in terms of Section 39 of the Water Act (1998) provided in Notice 509 of 2016 (GN 40229 of 26th August 2016) provides guidance and the conditions of authorisation regarding impeding and diverting the flow in a watercourse (Section 21 (c)), or altering the bed, banks, course and characteristics of a watercourse (Section 21 (i)). The recent amendment of the Section 21 (c) and (i) GA introduced a risk assessment matrix that allows for the determination of the level of risk associated with any given activity. Low risk water uses are generally authorised, requiring registration of the water use only, while activities with a moderate to high level of risk to the water resource require a full water use licence application.

7.1 Risk assessment matrix

The risk assessment matrix introduced in August 2016 adopts an approach similar to the EIA regulations, where each impact is assessed in terms of severity, likelihood and consequence. The matrix requires the assessment of each activity associated with the construction and operation of any development project in terms of the impacts expected to affect resource quality characteristics (flow regime, water quality, geomorphology, and habitat/biota) of watercourses and wetlands. Each impact is scored in terms of the severity of its effect on each of the resource quality characteristics, and the scores are then averaged to give a total for severity. Each impact is then scored in terms of its:

• Consequence, which is the product of the severity of the impact, the spatial scale or extent, and the duration of the impact; and

• Likelihood, which is the sum of the frequency of the activity, frequency of the impact, existence of legislation governing the activity and ecosystem; and the ease of detection of the impact.

The significance of the impact is calculated as the product of its consequence and likelihood. The final score is used to assign a risk rating to the impact, assuming implementation of effective mitigation measures.

7.2 Results of risk assessment

The results of the risk assessment of those activities associated with the proposed development of the Glencairn Hotel site that would trigger Section 21 water uses are presented in Table 7.1 and Table 7.2. It must be noted that the assessment of risks was done assuming that all the mitigation measures recommended in Section 6.2 are implemented.

In this case, the risks were all assessed as being low. However, this risk assessment depends on the success of implementation of the mitigation measures recommended in this report.


34

Table 7.1 Results of the risk assessment - CONSTRUCTION

Phases Activity Aspect Impact

Flow

Reg

ime

Phys

ico

& C

hem

ical

(W

ater

Qua

lity)

Habi

tat (

Geo

mor

ph +

Ve

geta

tion)

Biot

a

Seve

rity

Spat

ial s

cale

Dura

tion

Cons

eque

nce

Cons

truc

tion

Construction activities close to the wetland boundary

Dumping of building materials in close proximity to the wetland

Compaction of soils; movement of building materials (sand, rubble, etc) into the wetland

1 1 1 1 1 1 1 3

Leakage of fuels, oils, etc. from construction machinery.

Pollution of sensitive areas

1 1 1 1 1 1 1 3

Pedestrian access onto and around the construction site

Trampling of sensitive habitat; noise and light pollution; introduction and spread of alien invasive species

1 1 1 1 1 1 1 3


35

Table 7.1 Results of the risk assessment – CONSTRUCTION continued


Freq

uenc

y of

act

ivity

Freq

uenc

y of

impa

ct

Lega

l Iss

ues

Dete

ctio

n

Like

lihoo

d

Sign

ifica

nce

Risk

Rat

ing

Conf

iden

ce le

vel

Cont

rol M

easu

res

PES

AND

EIS

OF

WET

LAN

D

Cons

truc

tion

Construction activities close to the wetland boundary

Dumping of building materials in close proximity to the wetlands and watercourses

Compaction of soils; movement of building materials (sand, rubble, etc) into the wetlands or watercourses

1 1 5 1 8 24 LOW 80 See Section 6.2)

PES: D; EIS: high

Leakage of fuels, oils, etc. from construction machinery.

Pollution of sensitive areas 1 1 5 1

8 24 LOW 80

Pedestrian access onto and around the construction site

Trampling of sensitive habitat; noise and light pollution; introduction and spread of alien invasive species

1 1 5 1

8 24 LOW 80


36

Table 7.2 Results of the risk assessment – OPERATION


Flow

Reg

ime

Phys

ico

& C

hem

ical

(W

ater

Qua

lity)

Habi

tat (

Geo

mor

ph +

Ve

geta

tion)

Biot

a

Seve

rity

Spat

ial s

cale

Dura

tion

Cons

eque

nce

Ope

ratio

n

Stormwater discharge

Discharge of stormwater into wetlands and watercourses

Erosion of bed, banks and channel; increased water quantity entering natural systems; pollution; sedimentation in wetlands and river channels

1 1 1 1 1 1 2 4

Increased human presence

Noise and light pollution

Disturbance of fauna and flora 1 1 1 1 1 2 2 5

Landscaping and gardening

Introduction and establishment of invasive alien plants

1 1 1 1 1 2 2 5


37

Table 7.2 Results of the risk assessment – OPERATION continued


Freq

uenc

y of

act

ivity

Freq

uenc

y of

impa

ct

Lega

l Iss

ues

Dete

ctio

n

Like

lihoo

d

Sign

ifica

nce

Risk

Rat

ing

Conf

iden

ce le

vel

Cont

rol M

easu

res

PES

AND

EIS

OF

WET

LAN

D

Ope

ratio

n

Stormwater discharge

Discharge of stormwater into wetlands and watercourses

Erosion of bed, banks and channel; increased water quantity entering natural systems; pollution; sedimentation in wetlands and river channels

3 2 5 2 12 48 LOW 50 See Section 6.2)

PES: D; EIS: high

Increased human presence

Noise and light pollution Disturbance of fauna and flora 3 2 1 2 8 40 LOW 30

Landscaping and gardening

Introduction and establishment of invasive alien plants

3 2 5 1 11 55 LOW 70


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8 Rehabilitation and Monitoring

8.1 Rehabilitation

It is recommended that the banks of the Glencairnvlei outlet be rehabilitated. The objectives of rehabilitation would be as follows:

• Improved biodiversity value: This will be achieved through re-shaping and planting of the banks with appropriate wetland plants. These plants will attract a wider range of faunal groups (e.g. invertebrates such as dragonflies and damselflies, or vertebrates such as frogs and birds), than has previously inhabited or passed through the site. All invasive alien plants must be cleared from the area. These species tend to grow in disturbed soils, especially where there is available water, spreading further into previously undisturbed areas.

• Improved water quality: Planting of the banks will ensure that any stormwater entering the system will flow slowly through beds of plants and sediments, which play an important role in taking up excess nutrients and in capturing sediments, toxins and hydrocarbons. In this way, runoff entering Glencairnvlei is likely to be of good quality and unlikely to lead to a deterioration in water quality.

• Improved infiltration: Water attenuated by the rehabilitated areas will filter slowly into the ground, thereby improving the subsurface flow of water in the area.

• Maintenance of natural slope and geomorphology: The more gentle slope for the vlei banks in front of the hotel will reduce the likelihood of erosion and downstream sedimentation.

It is envisaged that the proposed rehabilitation will ensure that the PES of the vlei will not decrease, and may even lead to an improvement in condition locally at the outlet.

Some more detailed recommendations are made in the sub-sections that follow.

8.1.1 Re-shaping of bank slope

• A more natural, gentle bank slope should be reinstated along the Glencairnvlei outlet channel. Ideally, this should be achieved by hand and not machine.

• Re-shaped bank slopes should, in general, not be steeper than 1:3 (Russell, 2009). In some instances, where a less erosive longitudinal gradient cannot be achieved, a re-shaped bed may be stepped.

• It is recommended that the shape of the rehabilitated bank be fairly heterogeneous – with steeper sections and gentler sections, in order to mimic the natural shape of a bank.

• Work in the wetland shall be undertaken in such a manner so as to minimise the extent of impacts caused by the rehabilitation activities.

• It is important to consider using various stabilisation measures after the banks have been shaped, in order to prevent erosion. Stabilisation materials include:

o Ecologs (dry woody material or sand contained in a hessian and chicken wire roll – see Figure 8.1) – these are particularly effective in areas of low gradient;

o Biodegradable netting/matting (e.g. hessian); o Geotextile matting of thick filaments designed to be secured over a vulnerable

slope to prevent surface erosion, see Figure 8.1), and o Mulch stabilisation.


39

Figure 8.1 (Left) Ecologs installed for stabilisation, and (below) Banks stabilised by geofabric, showing natural re-

growth of indigenous species through the mat.

8.1.2 Removal of exotics and re-vegetation of cleared areas

• All kikuyu must be removed from the banks during rehabilitation. If kikuyu grass is to be sprayed, Focus Ultra should be used, which is preferable to Roundup near surface or groundwater resources. Spraying should preferably occur during the autumn, but if this is not possible, a follow-up spray should be done in the autumn following the original spraying. Dead grass can then be removed by hand.

• Cleared areas should be re-vegetated with seedlings rather than seeds. • Topsoil must be sourced from a reliable source, and must be free of weeds and invasive alien

plants and their seeds. Topsoil may be required in areas that have been scraped down to the subsoils.

• Mulch can be used in areas where planting is to take place. All mulch shall be free of alien species. Vegetative material that is to be chipped on site for mulch shall be reduced by either mechanical means (chipper) or by hand-axing to sticks no longer than 100 mm.

• Compost from a local source can also be utilised as mulch during planting and rehabilitation, but such compost must be well decayed, crumbly (friable) and free from weed seeds.

• Wood chips (including bark), which are half composted and have not been treated with preservatives can also be utilised as mulch during replanting and rehabilitation of the site. These shall only be obtained from indigenous species removed from the area through unavoidable clearing of areas of the site.

• Sods of wetland plants (such as sedges, grasses) are generally the best means of planting, rather than seeds. Plants should preferably be sourced from a local nursery, in order to maximise the genetic integrity of the plants.

• The following species are appropriate around the vlei outlet: o Bolboschoenus maritimus – sedge that grows in wetter areas (good filterer of

water), good combination with Ficinia nodosus, Elegia nudum and Juncus kraussii o Carpobrotum edulis (good stabiliser of soils) o Chondropetalum nudum – restio o Cyperus textilis – sedge


40

o Elegia capensis - restio o Elegia tectorum (margins of wetter areas) o Ficinia nodosus (margins of wetter areas) o Juncus kraussii (margins of wetter areas, or dry banks)

• Unless proper nursery conditions are created on site, plants should not be stored for longer

than 10 days on site prior to planting. • The planted areas shall be monitored for erosion, and areas that are subject to erosion should

be stabilised. • No fertiliser shall be used in the wetlands or watercourses. Fertilisers could have a negative

impact on the relatively nutrient-poor soils and sands of the site and surrounds, and thus on the associated vegetation, and also on the water quality within the wetland and in subsurface waters.

• No construction equipment, vehicles or unauthorised personnel should be allowed onto areas that have been planted. Only persons or equipment required for the preparation of areas and spreading of topsoil shall be allowed to work in these areas.

• All planted areas must be regularly monitored for weeds and invasive plants and all problem plants removed.

• Where there is significant die-back, areas must be re-planted. • Where necessary, compost or mulch must be applied, and plants pruned and / or staked to

prevent deterioration of the health of the plants. • Any cut, dead or pruned plant material shall be removed to an appropriate waste management

site.

8.2 Monitoring

The vlei outlet area should be monitored seasonally for at least three years after construction is completed. The rehabilitated banks should be monitored for invasive alien plant encroachment, and for the establishment of indigenous plants in revegetated areas. A very basic set of water quality variables should be monitored every 3 months in the vlei outlet itself – this should include in situ electrical conductivity, turbidity, pH, dissolved oxygen and chlorophyll-a (in the water column).

The requirement for monitoring is stipulated in GN 509 (see Section 4.6). The reasoning for this is to ensure that the risks/impacts identified and assessed are indeed of (at worst) low negative significance. The recommended monitoring indicators listed above will record sufficient information to make this judgement call.

It is the duty of the property owner (or homeowners association, for residential developments) to ensure that the monitoring takes place. Monitoring should be done by a suitably qualified freshwater ecologist. Annual reports (containing the data collected seasonally, i.e. every 3 months) must be submitted to the relevant DWS official (Bellville office).


41

9 Conclusions and recommendations • The proposed upgrade and development of the Glencairn Hotel site will affect the outlet channel of

Glencairnvlei. Glencairnvlei is fed by the Else River, which rises as a seasonal stream on the slopes between Grootkop and Red Hill. The river is approximately 7km long and drains an 18km2 catchment. Historically, Glencairnvlei was probably a seasonal system, with areas of open water occurring during the wet winter months, and drying up over summer (Day, 2001). The mouth of the vlei would generally have been closed, opening only after heavy rains in winter

• Erf 235 is located on the banks of the vlei outlet, and a proposed parking is planned to be constructed to the full extent of the erf. Erf 235 is essentially a flat plot, currently used for parking space and some commercial activities. The land not tarred for parking is covered by kikuyu grass, which has spread down the slope towards the Glencairnvlei outlet, with a few other planted exotic species. The vegetation type historically found on both erven is Cape Flats Dune Strandveld, an endangered vegetation type that occurs on alkaline sands.

• The current ecological condition of the Glencairnvlei has been significantly impacted by alterations to the natural hydrological regime of the ecosystem. This is due to the impoundment and abstraction of water in the upper Else River catchment (Kleinplaas and Lewis Gay dams), with smaller weirs and causeways located along the length of the remaining river. The shape and alignment of the wetland channels have also been altered through limited infilling for the construction of bridges over the river, and encroachment of developed areas on either side of the vlei. Flow obstructions and abstraction also lead to the loss of flushing flows through the system, and the build-up of sediments. The vegetation in the vlei has responded to these changes in hydrology and geomorphology, leading to establishment of beds of reeds and bulrush, instead of a more diverse wetland community. These existing impacts are reflected by the PES scores calculated for Glencairnvlei, giving the wetland an overall wetland PES of D – largely modified.

• The overall ecological importance and sensitivity of Glencairnvlei is high (score of 3), while the hydrological/functional importance is moderate and the human use rating is low (Table 3.5). The latter is due to the fact that the vlei does not provide services of direct benefit to the surrounding communities, such as potable or irrigation water, harvestable resources (such as reeds and restios, fish etc) or crops. The vlei does, however, provide an important feeding / breeding / migration node, in an increasingly urban area. While the species that the vlei supports are not necessarily rare or endangered, these species are important in terms of the overall biodiversity of the ecosystem. In addition, the vlei is sensitive to changes in low flows and water quality.

• The recommended minimum buffer for Glencairnvlei is 15m measured from the edge of the outlet wetland (as delineated in this report), for both the construction and operational phases, assuming that the vegetation cover currently covering the slope between the parking area and the outlet channel is revegetated with appropriate low-growing vegetation, as opposed to kikuyu grass.

• The most effective mitigation measure is avoidance of an impact. It is felt that the expected impacts associated with the proposed construction and operation of the Glencairn Hotel site development would best be mitigated through ensuring that no hardened surfaces are constructed within the recommended ecological buffer of 15m. An exception to this could be a wooden walkway.

• In addition to the recommended buffer, further mitigation measures deal with the reduction in the amount of stormwater runoff generated by the development, and improvement in the quality of water exiting the property. These measures focus quite strongly on the re-use of water on the property, which is appropriate given the water supply crisis currently persisting in the Western Cape. A proportion of the stormwater, combined with rainwater, could be cycled back into the development for re-use.

• In the light of these recommendations, the amount of runoff accumulating at the lower end of the site should not require storage within a detention pond. This may need to be verified by an engineer.


42

• In addition to water re-use, it is advised that all runoff be allowed to flow along unlined channels, wherever possible, with water being allowed to filter into landscaped areas. New parking areas should be constructed with permeable materials.

• Implementation of the mitigation measures recommended in this report will ensure that the risks to Glencairnvlei are of low negative significance, thus qualifying the proposed activities for general authorisation, according to GN 509 (2016), despite the proposal being located within 500m of a wetland.

• It is recommended that the banks of the Glencairnvlei outlet be rehabilitated. It is envisaged that the proposed rehabilitation will ensure that the PES of the vlei will not decrease, and may even lead to an improvement in condition locally at the outlet. The objectives of rehabilitation would be as follows:

o Improved biodiversity value: This will be achieved through re-shaping and planting of the banks with appropriate wetland plants. These plants will attract a wider range of faunal groups (e.g. invertebrates such as dragonflies and damselflies, or vertebrates such as frogs and birds), than has previously inhabited or passed through the site. All invasive alien plants must be cleared from the area. These species tend to grow in disturbed soils, especially where there is available water, spreading further into previously undisturbed areas.

o Improved water quality: Planting of the banks will ensure that any stormwater entering the system will flow slowly through beds of plants and sediments, which play an important role in taking up excess nutrients and in capturing sediments, toxins and hydrocarbons. In this way, runoff entering Glencairnvlei is likely to be of good quality and unlikely to lead to a deterioration in water quality.

o Improved infiltration: Water attenuated by the rehabilitated areas will filter slowly into the ground, thereby improving the subsurface flow of water in the area.

o Maintenance of natural slope and geomorphology: The more gentle slope for the vlei banks in front of the hotel will reduce the likelihood of erosion and downstream sedimentation.

• The vlei outlet area should be monitored seasonally for at least three years after construction is completed. The rehabilitated banks should be monitored for invasive alien plant encroachment, and for the establishment of indigenous plants in revegetated areas. A very basic set of water quality variables should be monitored every 3 months in the vlei outlet itself – this should include in situ electrical conductivity, turbidity, pH, dissolved oxygen and chlorophyll-a (in the water column).

• The requirement for monitoring is stipulated in GN 509 (see Section 4.6). The reasoning for this is to ensure that the risks/impacts identified and assessed are indeed of (at worst) low negative significance. The recommended monitoring indicators listed above will record sufficient information to make this judgement call.

• It is the duty of the property owner (or homeowners association, for residential developments) to ensure that the monitoring takes place. Monitoring should be done by a suitably qualified freshwater ecologist. Annual reports (containing the data collected seasonally, i.e. every 3 months) must be submitted to the relevant DWS official (Bellville office).


43

10 References Day, E.D. 2001. Management of Glenvlei wetlands. Letter addressed to Julia Wood, South Peninsula

Administration. 16 July 2001.

DWAF. 1999a. Resource Directed Measures for Protection of Water Resources. Volume 3: River Ecosystems Version 1.0, Pretoria. Resource Directed Measures for Protection of Water Resources, Pretoria, South Africa.

DWAF. 1999b. Resource Directed Measures for Protection of Water Resources. Volume 4: Wetland Ecosystems Version 1.0, Pretoria. Resource Directed Measures for Protection of Water Resources, Pretoria, South Africa.

DWAF. 2005. A practical field procedure for identification and delineation of wetlands and riparian areas. Department of Water Affairs and Forestry, Pretoria.

Gale, B.A. 2000. Report on various options for the management of Glencairn Vlei, including the Implications and Responsibilities of each option for the local residents and the local authorities. Final report No AQ 7/2A, for Cape Metropolitan Council and South Peninsula Municipality.

Helme, N. 2017. Botanical Specialist Report for Basic Assessment Process For Proposed Glencairn Hotel Development (Erf 2454), Glencairn, Cape Town. Report submitted to SLR Consulting, June 2017.

Kleynhans, C.J. 1996. A qualitative procedure for the assessment of the habitat integrity status of the Luvuvhu River (Limpopo System, South Africa). Journal of Aquatic Ecosystem Health 5: 41-54.

Kleynhans, CJ, Thirion, C and Moolman, J. 2005. A Level I River Ecoregion classification system for South Africa, Lesotho and Swaziland. Report No. N/0000/00/REQ0104.

Kotze DC, Marneweck GC, Batchelor, AL, Lindley DS and Collins NB, 2007. WET-EcoServices: A technique for rapidly assessing ecosystem services supplied by wetlands. WRC Report No TT 339/08, Water Research Commission, Pretoria.

Macfarlane DM, Kotze DC, Ellery WN, Walters D, Koopman V, Goodman P and Goge C. 2007. WET-Health: A technique for rapidly assessing wetland health. WRC Report No TT 340/08, Water Research Commission, Pretoria.

Milner, A.M. 1994. System recovery. In, P.Calow & G.E. Petts (eds.): The rivers handbook. Vol. 2. Blackwell Scientific Publications. London.

Ollis, D.J., Snaddon, C.D., Job, N.M. and Mbona, N. 2013. Classification System for wetlands and other aquatic ecosystems in South Africa. User Manual: Inland Systems. SANBI Biodiversity Series 22. South African National Biodiversity Institute, Pretoria.

Rebelo, A.G., Boucher, C., Helme, N., Mucina, L. and Rutherford, M.C. 2006. Fynbos Biome. In Mucina, L. And Rutherford, M.C. (eds.). The vegetation of South Africa, Lesotho and Swaziland. Strelitzia 19: 52 – 219).

Resh, V.H., A.V. Brown, A.P. Covich, M.E. Gurtz, H.W. Li, G.W. Minshall, S.R. Reice, A.L. Sheldon, J.B. Wallace and R.C. Wissmar. 1988. The role of disturbance theory in stream ecology. Journal of the North American Benthological Society. 7: 433-455.

Rountree, M.W., Malan, H.L. and Weston, B.C. 2013. Manual for the Rapid Ecological Reserve Determination of Inland Wetlands (Version 2.0). Water Research Commission Report 1788/1/13, 170 pp.

Snaddon, K. and Ewart-Smith, J. 2005. City of Cape Town Bulk Water Infrastructure Planning Study: Freshwater ecosystems scoping study. Report prepared for City of Cape Town Council (Orrie Welby-Solomon & Associates / BKS), October 2005.

Turpie, J. and Clark, B. 2007. The Health Status, Conservation Importance, and Economic Value of Temperate South African Estuaries and Development of a Regional Conservation Plan (Draft


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Report). Anchor Environmental Consultants CC for C.A.P.E. Regional Estuarine Management Programme & Cape Nature.

APPENDIX G2 FRESHWATER ECOLOGICAL INPUT · upgrade is located on two erven Erf 2454 (8– 444 m 2)...

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