Strategic Assessment of Water in the Saldanha LM · Strategic Assessment of Water in the Saldanha...

1

Strategic Assessment of Water in the Saldanha LM

Prepared by: Arthur Chapman

Inputs from: Herman Jonker

Date: 12 July 2019

Contents 1. Introduction ................................................................................................................................5

1.1 Methodology .......................................................................................................................5

2. Water Quantity ...........................................................................................................................5

2.1 Current Status of Fresh Water Resources in the Saldanha Bay Local Municipality ................5

Key sectors of water demand – drivers and pressures ..................................................7

Timeline of water abstractions for Saldanha Bay Local Municipality .............................8

Water Resources Infrastructure ...................................................................................9

Waste water re-use and efficiency initiatives ............................................................. 10

2.2 Trends Driving Changes in Water Quantity......................................................................... 11

The likelihood of drought in the region and climate change ....................................... 11

Options for increasing supply ..................................................................................... 11

Trends in Future Water Supply to the Region ............................................................. 14

2.3 Risk Assessment – Water Quantity..................................................................................... 16

Definitions ................................................................................................................. 16

Risk rating .................................................................................................................. 16

3. Water Quality............................................................................................................................ 18

3.1 Status of Fresh Water Quality ............................................................................................ 18

Eutrophication ........................................................................................................... 19

Salinisation ................................................................................................................ 20

Inorganic pollutants ................................................................................................... 20

Microbial contamination ............................................................................................ 20

Emerging contaminants ............................................................................................. 20

3.2 Trends driving changes in water quality ............................................................................. 20

3.1 Risk Assessment – Water Quality ....................................................................................... 24

4. Trends in Governance ............................................................................................................... 28

5. Conclusions - Strategic Perspectives for the Saldanha Bay Region ............................................. 28

5.1 Water quantity .................................................................................................................. 28

5.2 Water quality..................................................................................................................... 29

6. References ................................................................................................................................ 31

2

Abbreviations and Terminology

SBLM Saldanha Bay Local Municipality

MAR Mean annual runoff

NFEPA National Freshwater Ecosystem Priority Areas

TEC Target Ecological Category – the sustainable preferred condition of a water body

including utilisation

URV Unit Reference Value, used to compare different water resource development

options using the cost per unit volume of water delivered, including all capital,

operational and maintenance costs over a specified time period

WCWSS Western Cape Water Supply System

WMA Water Management Area

WTW Water Treatment Works

ZED Zero Effluent Discharge – industrial processes in which no waste water is emitted

from the premises

3

SUMMARY

The water obtained by the Saldanha Bay Local Municipality is supplied mostly from the Western Cape

Water Supply System (WCWSS). This system manages water captured, stored and transferred within

both the Berg River and Breede River Water Management Areas. While the Saldanha Bay Local

Municipality (SBLM) lies in the Berg Water Management Area, the WCWSS extracts water from both

the Berg and Breede Water Management Areas (WMAs). Therefore the two WMAs need to be

managed as a strategic whole.

The SBLM is mostly supplied from the Withoogte water treatment works, which obtains its water from

the Berg River at the Misverstand Weir. The total integrated system yield of the WCWSS at 98%

assurance of supply for all user categories (based on original planning – not taking into account the

2015-2017 drought) is 596 million m3/a. This value does not accommodate sufficient allocations to

the environmental reserve.

Water scarcity in the Berg River system is now at a premium as a result of the abstractions and

utilisations of different sectors. Further water supplies may become available to the SBLM as a result

of incremental augmentation of the WCWSS, starting with developing more capacity at Voëlvlei Dam.

Nevertheless, this water will have to be shared with other users, including the City of Cape Town.

In the future, the assurance of supply of surface waters in the WCWSS at current or incrementally

higher levels of demand, will decline as the system is reaching its capacity to supply water. Further

water resource projects will supply only marginally greater amounts of water, of which a portion can

be made available to SBLM. Climate modelling indicates that, in the longer term 30-50 year time

horizon, declining rainfall in the Western Cape will generally increase scarcity of available surface water

in the region. Planning and governance needs to accommodate this outlook.

The area of greatest contribution of surface water to sustainable water access for SBLM will be through

recycling (water re-use) and desalination. Desalination should particularly be considered where

recycling can be implemented as desalination produces a high-cost product (relatively) and recycling

preserves the high cost product and is resource-efficient. This approach is a central feature of the

circular economy.

The key risks posed to water quantity in the WCWSS include poor governance, climate variation and

particularly rising and inelastic demand by urban users. This is not caused particularly by users in the

SBLM but within the WCWSS as a whole. Industrial users pose less of a risk to the system because they

can recycle more easily; and because some water quality parameters are not as important to the

industrial user as they are to the urban user. Agricultural users have a lower assurance of supply and

are (or should be) curtailed earlier during droughts. All of these risks, except climate variation, can be

mitigated with appropriate inputs, investment and high levels of appropriate governance. The Target

Ecological Categories (TEC) of the sections of the Berg River can be met with careful management with

respect to water quantity. However, several tributaries are being utilised beyond their ecologically

sustainable capacity. Achieving the sustainable ecological needs of the system means less water is

actually currently available to the major water users of the WCWSS than at present. This should focus

vulnerable users such as the SBLM on the need to develop other sources of water, such as improved

water recycling and desalination, of which these two solutions should be specified together.

The Berg River, from which SBLM obtains most of its water, has increasingly severe water quality

challenges. Much of this is a result of the influences specifically arising up-river of any particular

influences or effects of activities within the SBLM. Agricultural runoff, which is a diffuse source of

4

nutrients, winery effluents and poorly-functioning waste water treatment plants lead to

eutrophication. Irrigation return flows, industrial processes and some groundwater flows lead to

salinization. Surface water contamination from poor sanitation and unmanaged stormwater runoff

from informal settlements around Paarl leads to microbial contamination. Surface water runoff from

areas around industrial and metal processing and finishing industries leads to inorganic pollutants.

Finally, there is the question of the rising concentrations of emerging pollutants, which includes

pesticide residues and chemicals affecting the endocrine systems of living organisms.

The situation of these contaminants is made worse when water flows in the river decline, leading to

higher concentrations of contaminants during severe droughts, and exacerbated by a lack of oversight

and lack of monitoring and control. Included are the challenges of human behaviour, which manifest

in vandalism and poor maintenance, result in sewage flows into the river.

Good water quality is an important aspect of ecosystem services. Good quality water has attributes of

provisioning and supporting human life and aquatic biodiversity, provides buffering functions to

variable river systems and has strong cultural affinities through human enjoyment of clean and clear

water features.

The prime risks to water quality are posed by poor governance, climate variation, industrial pollution,

negative human behaviour and contaminated urban and informal settlement runoff. These can all be

mitigated to some extent by interventions, noting that such interventions will be outside of the SBLM.

Sections of the river and its tributaries are already shown to be substantially below acceptable water

quality conditions. These Target Ecological Categories (TECs), have been recently promulgated and

show that significant effort needs to be spent on retrieving the system to a more sustainable level that

is less impacted. SBLM water users need to influence the various role players in the governance and

management of water quality so that the declines in water quality can be reversed.

5

1. Introduction The likely economic and population growth trends in the Saldanha Bay Local Municipality (SBLM) will

determine its future water demands, but also be influenced by constraints on water supplies to the

area. This document is the surface water and water quality component of a Strategic Environmental

Assessment (SEA) that is assessing the capacity for the area to accept greater economic development,

which will bring greater demands for resources in the region, including water.

The Terms of Reference specify an assessment of the risks of the developments to the environment.

This assessment covers the risks attendant to both water quantity and quality and considers surface

water only, the groundwater situation is a separate study. In the case for fresh water, the need to

supply possible developments at Saldanha with fresh water is what has an impact on the environment.

1.1 Methodology

This assessment is conducted at the scale of the Western Cape Water Supply Systems (WCWSS), but

with particular focus on the Berg River. The Saldanha Bay Local Municipality obtains its water outside

of the municipal boundaries and the river system is managed as part of a much larger whole, as will be

seen from the various diagrams and descriptions of the system. Therefore, assessments are made for

the system at the larger scales, because the demand for water by the Saldanha Bay Local Municipality

(which incorporates urban and industrial users) cannot be separated or analysed independently from

the rest of the WCWSS. (Note: The extent to which the local municipality sources bulk water from

aquifers within the Municipal area is covered in the groundwater study).

A formal risk assessment approach is used, which considers the risks of demand on available water

quantity and water quality, respectively. A risk assessment has a structured approach: Likelihood of

an impact is estimated, which means a reduction in river flow of different levels that is dependent on

the nature of water use and re-use, and the consequence of such reductions in river flow, which are

then evaluated together where risk is a combination of consequence and likelihood.

The same approach is adopted for a separate assessment of water quality, in which the consequence

of declining water quality is evaluated along with the likelihood of an impact by economic

developments in the Saldanha Bay LM.

A sensitivity analysis is then undertaken, in which sensitivity classes are assigned to features of natural

capital and then estimating the likelihood of the driver-pressure-impacts on these different sensitivity

classes, where feasible, for the water quantity and quality risk assessments. System resilience is

considered as part of the analysis and risks are also considered with and without Best Practice

Management actions.

2. Water Quantity

2.1 Current Status of Fresh Water Resources in the Saldanha Bay Local Municipality

The water supplies to the Saldanha Bay LM can only be considered within the context of the larger

water supply system that concerns the City of Cape Town and its environs. This is the Western Cape

Water Supply System (WCWSS). It is designed as a multipurpose system, supplying water to the City

6

of Cape Town as well as surrounding towns, as well as to agriculture and regulating (in part only) water

allocations to the environment. The WCWSS therefore has an influence on all major water abstractions

and transfers in the greater Cape Town environs and associated local municipalities.

The Saldanha Bay LM lies in the Berg Water Management Area and is supplied by the WCWSS. The

WCWSS extracts water from both the Berg and Breede Water Management Areas (WMAs), therefore

the two WMAs need to be managed as a strategic whole (Fig 1). Therefore, the supply of water to

Saldanha LM is influenced by water supplies in the larger system that extends into the Breede WMA.

The Saldanha Bay LM is mostly supplied from the Withoogte treatment works, which obtains its water

from the Berg River at the Misverstand Weir (Fig 2). The Berg River at the point of entry to the

Misverstand Weir receives water from its own run-of-river upstream and a transfer from the Voëlvlei

Dam, which in turn is supplied by a canal from the Klein Berg river, which drains the Tulbagh valley.

Flows in the Berg River are regulated now principally by the Berg River dam but also has numerous

abstraction points along its course, mostly by adjacent agricultural off-takes. The Berg River at a point

just downstream of the dam receives water either from the dam (as regulated flows) and via an inter-

basin transfer scheme that directs water from the Theewaterskloof Dam (via the Charmaine inlet)

under the Drakenstein mountains. Water can flow both ways in this tunnel, so if there are sufficient

flows on the Berg System (on the Banhoek River), they can be directed towards the Theewaterskloof,

which is the principal dam in the system at 480 million m3 (Fig 2). Water from the Breede WMA,

therefore, is directed into other sections of the Berg WMA as part of the extended water supply

systems of these two WMAs. There are other extensions to the WCWSS but these are not discussed

here as they are not intimately connected to the water flows to the Misverstand Weir.

The strategic assessment area for the water considerations of supplies to Saldanha Bay LM therefore

stretches all the way from the Berg River estuary at Velddrif 26 km to in the north east of Saldanha, to

the mouth of the Breede River at Witsand 300 km to the south east (Fig 2). That is, it is not constrained

to any particular zoning around the Saldanha Bay LM development region.

The total integrated system yield of the WCWSS at 98% assurance of supply for all user categories

(original planning – not taking into account the 2015-2017 drought) is 596 million m3/a. This value

does not accommodate sufficient allocations to the environmental reserve. Implementing allocations

to the reserve will reduce this total system yield (Seyler and Millson, 2015).

Total water allocation to agriculture is capped to about 170 million m3/a for the whole of the WCWSS.

Actual use has been limited to 134 -160 million m3/a since 2011 (DWS, 2016a). Water use in the Berg,

Olifants, Breede and Gouritz WMAs already exceeds supply (that amount allocated with consideration

to environmental needs). Therefore, the environment – the aquatic or environmental allocation, is

currently in deficit by some accounts (See Table 3-2 of p11 of . The Berg WMA is therefore already in

deficit by some 36 million m3/a although this is contradicted by later studies which show the total

supply in the Berg WMA at 709 million m3/a and use is estimated at 690 million m3 /a., given in DWA

(2011) and DWS (2017a, 2017b).

The volume of water use in the Berg WMA is different to that used in the WCWSS and the two entities

should not be confused. Total water use in the Berg WMA is about 700 million m3/a, which includes

runoff capture, storage and use on private farm dams and is not evaluated as part of the WCWSS.

These other users in the Berg WMA, such as agriculture, account for the difference and this water is

not necessarily available for further use within the greater WCWSS, at present and in the near future.

The system yield in the WCWSS is 596 million m3/a (DWS, 2016a).

Given the importance placed on agriculture in terms of the export market, employment opportunities

and as an important part of the Western Cape tourist industry, it is unlikely that there will be any

7

substantial diversion of water away from agriculture and into urban and industrial use (even though

the economic value addition per unit of water used in the latter is higher).

Key sectors of water demand – drivers and pressures

The following sectors make up the different water users in the Saldanha Bay LM. Water availability is

however also strongly affected by climate variation and change (for example occasional severe

drought) as well as being managed as part of the larger water supply system – the WCWSS):

Minerals – extraction and processing

Urban and commercial users

Agriculture – depletion through use

Fisheries – cleaning and processing

Port services

DWS (2016) shows that urban water use in the Berg and Breede WMAs combined, is declining from

67% (agriculture 33%) in 2006 to 65% (agriculture 35%) in 2015 (DWS 2016). The proportion of water

supplies and demands in the Berg and Breede WMAs are detailed below to illustrate the where the

bulk of the water is being obtained from and where it is being used, showing the relative importance

of each component in relation to the others. Current water supplies and uses in the Berg and Breede

WMAs are listed in Tables 1 and 2 (Adams et al., 2018; DEA&DP, 2013).

Table 1 The proportions of the sources of water supply and water use in the Berg River Water Management Area

Berg WMA Water Supply Water Use

56% Surface water 53% Urban and industrial use

27% Net transfers in 42% Irrigation

8% Groundwater 3% Preliminary reserve

7% Useable return flows

1% Plantations 1% Afforestation / plantations 1% Potential aliens invasive removal 1% Invasive alien plants

Table 2 The proportions of the sources of water supply and water use in the Breede Water Management Area.

Breede WMA Water Supply Water Use

77% Surface water 68% Irrigation 11% Groundwater 18% Net transfers out

9% Useable return flows 7% Invasive alien species

2% Potential afforestation removal 4% Urban use

1% Potential alien plant removal 2% Preliminary reserve

1% Afforestation / plantations

The drivers and pressures within the system controlling water supply to Saldanha Bay LM are more

fully described as follows in Fig. 3 and Table 4:

8

Figure 1 Influence diagram describing the key components affecting surface water resources in the WCWSS and the Saldanha Bay Local Municipality

As a region, the West Coast and the Saldanha Bay LM in particular has the potential for a 0 – 5%

reduction in runoff due to water use by invasive alien plants. This means there is little further water

available from any considerable effort to reduce the stands of invasive alien trees in the West Coast

area (Adams et al., 2018). Artificial recharge of surplus surface waters (storm water and treated waste

water) is actively managed at Atlantis Water Management Area and supplies about 30% of water used

in Atlantis (DWA, 2010). The Atlantis Water Management Area supplies water to the urban centres of

Atlantis, Mamre and Pella. The drivers and pressures on the water resources in the WCWSS are shown

in Fig. 3.

Timeline of water abstractions for Saldanha Bay Local Municipality

A 10-year timeline of water abstractions from the Berg River for treatment in the Withoogte WTW is

given in Table 3. The official allocation here is 17.4 million m3/a or 48 000 m3/d. This is quickly

exceeded between 2012 and 2014. The effect of the drought is noticeable in cut-backs from 2015

onwards to significantly less than allocated.

Various scenario planning and business planning reports have indicated that the water demand in

SBLM would rise to 60 000 m3/d or 21.9 million m3/a already by the middle of the decade. However,

as indicated, extractions by 2013 were already exceeding the planned allocation of 17.4 million m3/a.

The “deficit” (allocation minus extraction) is taken from the environmental reserve. Applications to

the WCWSS for more water are in competition with those from the City of Cape Town and no further

allocations by DWS have been designated (Pengelly et al., 2017). It is clear that the SBLM remains in a

highly water-constrained environment. Future allocations may become available in the future as

further water supply options are developed, as explained later. However, these are unlikely to meet

future business demands if current water use patterns are maintained.

9

Table 3 Water abstractions for Withoogte water treatment works, for supply to Saldanha Bay Local Municipality

Year x 1000 m3/day

Source

2019 25 (Greencape, 2018)

2018 28 “

2017 37 “

2016 39 “

2015 41 (Pengelly et al., 2017)

2014 55 “

2013 51 “

2012 48 “

2011 47 “

2010 47 “

Water Resources Infrastructure

The key water supply to the Saldanha region are via two pipelines, i.e. from the Misverstand Weir on

the Berg River and the Voëlvlei Dam. During times of water stress such as happened in the 2015-2017

drought, extra water was first released from Voëlvlei but it was shown that the release was too small

to have sufficient hydraulic head to create a pulse of water that could efficiently reach the Misverstand

Weir and most of the release was lost (Mr H. Jonker, pers. comm. 2019). A substantial release of 5

million m3 was then required from the Berg River Dam, which finally allowed water to flow to the

Misverstand Weir. Much of it (about 2 million m3) was lost along the way, firstly to re-establish bank

storage which had been lost during the extended low flow through the drought and secondly by

possible opportunistic and illegal abstractions by various water users along the river (Mr H. Jonker,

pers. comm. 2019).

Table 4 The relationships amongst water resource system variables

Impact Driver Pressure on water quantity

How do the drivers, pressures and impacts interact specifically within SALDANHA BAY LM?

Wat

er Q

uan

tity

Re

du

ctio

n

Poor Governance Seasonal and intra-annual excessive reductions in river flows in the WCWSS. Declining water availability and reliability

Misallocation within the WCWSS – failure to curtail excessive use early enough during drought, failure to plan investments timely, failure control abstractions, results in excessive loss of river flows in the water supplies to SALDANHA BAY LM, drying up of Berg River below the Misverstand Weir, with severe impacts on aquatic ecosystems and Berg River estuarine function, as well as severe exposure to total failure of water supplies Saldanha Bay LM

Climate variation and change Loss of flows in the WCWSS rivers

Seasonal or inter-annual severe water shortages across the WCWSS, curtailed economic and agricultural activity, loss of ecosystem functioning and integrity, the low river flows result in an effective concentration of pollutants

Industrial demand Reductions in river flows in

Constant demand for water and appropriation of water supplies in the WCWSS, leading to increased competition for water and negative impacts on aquatic

10

the WCWSS

and estuarine ecosystem, leading to whole-ecosystem stress and loss of resilience

Urban demands Reductions in river flows in the WCWSS

Constant demand for water and appropriation of water supplies in the WCWSS, leading to increased competition for water and negative impacts on aquatic and estuarine ecosystem, leading to whole-ecosystem stress and loss of resilience

Agricultural users reductions in river flows in the WCWSS


Bulk water supply to other users - WCWSS

Reductions in river flows in the WCWSS


Fish processing Reductions in river flows in the WCWSS


Commercial forestry Reductions in river flows in the WCWSS


Invasive alien trees Reductions in river flows in the WCWSS


Waste water re-use and efficiency initiatives

Water recycling and re-use is an obvious way to reduce total water demand while maintaining the

utility of water in any processes which require it. Most processes consume some water (process

wastes are separated and solidified in evaporation ponds) and so water supplies need to be maintained

at a high level of assurance of supply. Nevertheless, various water users may be able to reduce their

total demand by cleaning and recycling their own waste water, or by receiving the waste waters from

other sources, reducing total system use. As a result of the general water scarcity in the West Coast

region, significant recycling and re-use of waste water is already occurring in the SBM. Efficiencies have

increased substantially, as a result of the pressures of the 2015 to 2017 drought, consumption was

reduced from about 37 m3/d to 22 m3/d, a reduction of 40% (Mr H Jonker, pers. comm. 2019).

There are three waste water treatment works in the Saldanha Bay LM, at the towns of Langebaan,

Vredenberg and Saldanha itself. The Langebaan municipal waste water treatment plant produces

about 3 000 m3/d, most of which is used by the golf course but during wet weather, irrigation stops

and the excess effluent goes into Saldanha Bay. The Vredenberg municipal treatment plant produces

about 5 000 m3/d, which is currently not re-used. Work is being done to install a pipeline from the

Vredenburg WWTW to convey 1 000 m3/d to the steel and metals processing industries, with Arcelor

Mittal likely to take 1 000 m3/d and Tronox or Duferco another 500 m3/d (Mr H Jonker, pers. comm.

2019). The excess at present is discarded into Saldanha Bay. The Saldanha Bay Industrial

Development Zone (IDZ) waste water treatment works were recently upgraded from 2 500 m3/d to 5

000 m3/d. Improvements to sewers in the back-of-port area have also been undertaken recently.

Saldanha Steel has cut its effluent discharge to zero in a process known as Zero Effluent Discharge

(ZED) (Arcelor Mittal, n.d.). This amounts to some 600 m3/day of effluent capture and re-use.

11

2.2 Trends Driving Changes in Water Quantity

The likelihood of drought in the region and climate change

Persistent drought over the whole Western Cape region began in 2015. The region had received above

average rainfall from 2009 to 2014 (Adams et al., 2018). The Western Cape Province was declared a

disaster area on 22 May 2017. Severe curtailments began in 2017 to all users (NDMC, 2016). The West

Coast and Winelands were declared disaster areas already in 2015 due to drought. Economic losses

run to billions of Rand (DEA&DP, 2016). Crop losses as high as 50 -100% have been recorded in the

West Coast District Municipality (DoA, 2016). The cause of drought has not been attributed to any one

particular global and synoptic circulation change. A particular mode of the South Atlantic Oscillation

(SAO) is likely one of the causes of the drought (Dr P Johnston, pers comm. 2019).

Climate change projections for the Western Cape for the forthcoming 30 - 50 years include declining

rainfall (DEA, 2013). The trends include a general drying from west to east and potential increases in

summer rainfall (more likely in the north and east of the Western Cape Province than close to the

coast). There will also be a general rise in temperatures, which will result in a rising evaporative

demand as well as a rise water demand for irrigation. Currently, the WCWSS planning does not feature

climate change in its water yield projections (DWS, 2016).

Options for increasing supply

The following options (see Table 4) for increasing supply in the WCWSS have been noted (from a

compilation of various DWS and other planning documents) (Seyler and Millson, 2015). Given the size

of the current water use and growing demand, these incremental amounts do not add much to the

total supply and do not provide options for significant increases in demand. It should be noted that

the lower part of the Berg River system and some of the tributaries contributing to the WCWSS are

already stressed.

An additional take-away point is that the total amount of water available and used is not consistent in

all of the reports, therefore these figures should be used with circumspection. The final point is that

current use is close to or over limits of sustainable supply. Most towns in the WC District Municipality

and all towns within the Saldanha Bay LM already exceed allocations (Adams et al., 2018). However,

Table 4 shows that there are options for limited increases of supply to the WCWSS, part of which could

be available to the Saldanha Bay LM.

Table 5 Short to medium term water resource developments for the WCWSS that could affect or increase water supplies to Saldanha Bay LM (Source: Seyler and Millson (2015). Note that Re-use Options, Table Mountain Aquifer and Desalination are not surface water components per se.

Intervention

Earliest implementation year

Yield million m^3/yr

1 Voëlvlei phase 1 2021 23

2 Re-use Option 1 2022 40

3 Table Mountain Group Aquifer Scheme 1 2024 20

4 Re-use Option 2 2024 50

5 Table Mountain Group Aquifer Scheme 2 2026 30

6 West Coast aquifer storage 2027 14

7 Desalination phase 1 2028 50



10 Voëlvlei phase 2 and 3 2035 110

12

Figure 2 Map of the water catchment areas supplying the Western Cape Water Supply System

13

Figure 3 A simplified schematic of the Western Cape Water Supply System (WCWSS) that includes those components affecting the West Coast DM and Saldanha Bay Local Municipality. Not all supply lines and tributaries of dams are shown.

14

Trends in Future Water Supply to the Region

Water resource development usually follows the curve of least cost. Using the Unit Reference Value

(URVs) of different development options, the likely development pathway follows in order of

ascending cost (see Table 4 and Figures 4 and 5):

1. Surface water resources – few further options available for significant amounts of water, but

see Table 4, in which Voëlvlei phases 1-3 are surface water options specifically. Surface water

sources are the cheapest (by significant amounts) of all options

2. Recycling and re-use. This source of water has not been substantially developed in the

WCWSS, for a variety of reasons but is already substantially adopted in the Saldanha Bay LM,

even if the water recycled is used one additional time and then discarded. The Vredenberg

municipal treatment plant has potential for water re-use (refer to section 2.1.3). As water

scarcity increases, this option will likely become more prevalent. Technology already exists

that can deliver recycled water at acceptable costs and current estimates put it as the next

best cost of resource in term of increasing cost of supply (considering all other options of

supply).

3. Further development and use of groundwater resources. While groundwater development is

often seemingly an attractive option, the size, sustainability and quality of the groundwater

resource remains substantially unknown and significant further research into the resource

viability is still required. Note: Refer to the groundwater balance calculations in the

Groundwater specialist study, which estimates that the utilisable groundwater exploitation

potential in the SBLM area from the Langebaan Road aquifer (operational since 1999) and the

Hopefield wellfield (under development) is approximately 6.91 million m3/a.

4. Desalination. This option is the most expensive of all. The process is highly energy intensive ~

3 kWh/m3, so that at 150 ML/d plant incurs operating costs of ~ R360k/d (not including the

depreciation of capital costs). Consequently, many large desalination plants globally are not

functioning optimally – for similar reasons of high cost. Desalinated sea water needs to be

recycled, as a way of reducing its total lifecycle costs. The global benchmark for cost of

desalinated water from medium to large-scale plants is 1 USD/m3, with this cost declining in

some cases of large-scale desalination development such as for cities in Israel, where 0.6

USD/m3 has been shown to be possible through efficiency engineering (Talbot, 2015).

The ordering of the development of the various water supply options may be changed according to

the planning horizons involved. Further development of surface water – over a 5 - 10 year time

horizon, includes small-scale desalination in 1 – 2 years, larger-scale desalination 2 - 5 years,

groundwater abstraction 6 months to 2 years, recycling from 5 – 10 years. The most expensive option,

desalination, is also the quickest to implement and remains attractive for that reason, but soon falls

out of favour with the public as a result of the high costs of buying desalinated seas water. Figures 4

and 5 indicate that as water resources become increasingly scarce, costs of meeting rising water

demand increase dramatically, although the most expensive water is used the least. The complexity

of water governance similarly increases as different water sources are added.

15

Figure 4 Future water supply options follow a cost curve, with uncertain costs according to local contexts (red margins)

Figure 5 The proportion of the different sources of water are inversely proportional to their costs of acquisition.

Flowing water provides important ecosystem services. Those for the WCWSS and in general are listed

in Table 4.

Table 6 Important ecosystem services that result from fresh water quantity in the greater Western Cape Water Supply System

CATEGORY ECOSYSTEM SERVICE

Provisioning Contributes to human well-being through water provisioning for drinking, cleaning (health provisioning), food production (irrigation, fish protein) and maintenance of aquatic ecosystems

Regulating Secondary regulating effects though maintenance of other environmental services which then have a regulating effect, otherwise, less evident

Regulates water quality through dilution effects

Supporting Supports other ecosystem services – such as maintenance of wetlands, aquatic ecosystems, habitat maintenance, tourist attractions Supports habitat for various fauna and flora of recreational and scientific interest

Cultural

Important cultural services – fresh water environments are preferred recreational areas, sporting environments, tourist visitations, which in turn support local and regional economies

Religious – cleansing ceremonies

16

2.3 Risk Assessment – Water Quantity

Definitions

Risk assessments require that the consequence and likelihood ratings be defined, which are given

below: Likelihood has a probabilistic attribution with the following values:

Extremely unlikely (EU)= 1:10 000

Very unlikely (VU) = 1 :100

Not likely (NL) = 1:20

Likely (L) = 1:2

Very Likely (VL) = 1:1

The consequence term is defined in Table 6 below:

Table 7 The consequences terms of reduction in river flows as a result of water supplies to the WCWSS

Consequence Term Consequences of loss of river flow

Slight <10% reduction in mean and flushing river flows Little to no alteration of regional ecosystems, well within natural variability, within the absorptive, adaptive and restorative capacity of the WCWSS, well within acceptable limits of change

Moderate 33% reduction in mean and flushing river flows Some physical loss of threatened riverine and estuarine habitat, contraction of riparian margins, minor alterations to regional ecosystem service functionality that includes all of the areas affected by the WCWSS, within the absorptive, adaptive and restorative capacity of the WCWSS, well within acceptable limits of change

Substantial 50% reduction in mean and flushing river flows Noticeable physical loss of threatened riverine and estuarine habitat, contraction of riparian margins, minor alterations to regional ecosystem service functionality that includes all of the areas affected by the WCWSS, within the absorptive, adaptive and restorative capacity of the WCWSS, well within acceptable limits of change

Severe 67% reduction in mean and flushing river flows Substantial physical loss of threatened riverine and estuarine habitat, severe contraction of riparian margins, substantial alterations to regional ecosystem service functionality that includes all of the areas affected by the WCWSS, the absorptive, adaptive and restorative capacity of the WCWSS requires several annual cycles to restore to previous acceptable functionality

Extreme >80% reduction in mean and flushing river flows The rivers occasionally dry up, with very substantial, permanent physical loss of threatened riverine and estuarine habitat, semi-permanent contraction of riparian margins, very substantial alterations to regional ecosystem service functionality that includes all of the areas affected by the WCWSS, the natural system is unable to absorb, adapt and restore to previous acceptable functionality

Risk rating

Using the above definitions of likelihood and consequences, Table 7 represents the risk ratings,

additionally with a section or risk with mitigation.

17

Table 8 Risk rating from likelihood and consequence assessments of water quantity impacts caused by demands in different economic sectors (EU=Extremely Unlikely, VU=Very Unlikely, NL=Not Likely, L=Likely, VL=Very Likely)

Impact Without mitigation With mitigation

Wat

er Q

uan

tity

Red

uct

ion

Driver Pressure Like. Cons. Risk Like. Cons. Risk

Poor Governance Excessive reductions L Substantial High NL Moderate Low

Climate variation Excessive reductions VL Moderate High VL Moderate High

Industrial users Flow reduction L Moderate Mod L Slight Low

Urban users Flow reduction L Severe High L Moderate Mod

Agricultural users Flow reduction L Moderate Mod L Moderate Mod

Bulk water supply Flow reduction L Moderate Mod L Moderate Mod

Fish processing Flow reduction L Slight Low L Slight Low

Afforestation Flow reduction L Slight Low L Slight Low

Invasive trees Flow reduction L Slight Low L Slight Low

An assessment was undertaken on the preferred flows and qualities of the Berg River system in terms

of the conjunctive use and the status of the river in terms of its ecological sustainability, called Targeted

Ecological Category (TEC) given in Table 8 of Government Gazette (2019). Where flows are

appropriated way above their natural condition preferred ecological condition – these show the

highest sensitivity in terms of water use. Flows in the Quaternary catchments G10A and G10G are

appropriated to the extent that only 23 – 27% of mean annual runoff (MAR) remains in the river

system, whereas the preferred condition (some use) at ~50% and given a TEC of category C

(Government Gazette, 2019). Table 9 then describes the Best Practice Management as a way of

achieving these goals (which is the same as mitigation (Table 7).

Table 9 Sensitivity Table for water quantity at monitoring nodes (TEC data from Government Gazette, 2019)

Integrated Unit of Analysis (IUA) Quaternary TEC % nMAR Sensitivity

Berg Estuary G10M C 52 High

Upper Berg G10A A 98 Low

G10A C 27 Very high

G10C D 53 High

Middle Berg G10C C 366 Moderate

G10D D 89 Low G10D D 49 High

Berg Tributaries G10E C 82 Low

G10G B/C 23 Very High

Lower Berg G10J D 52 High

G10K D 51 High

Table 10 Best Practice Management, monitoring and limits of acceptable change for water quantity

Impact Driver Pressure Describe best practice management actions

Identify best variables and suitable systems for monitoring

Identify limits of acceptable change

Poor Governance

Seasonal and intra-annual excessive reductions in river flows in the WCWS. Declining water

Current monitoring systems run by DWS are insufficient to meet the requirements of a

The TEC for different segments of the Berg River are listed in Government Gazette (2019)

The Target Ecological Categories (TEC) for each river segment, see Government Gazette (2019) needs to be achieved where

18

availability and reliability

well-monitored system. Monitoring systems have been withdrawn as a result of lack of resources in DWS

excursions from the TEC exist.

Climate variation and change

Loss of flows in the WCWSS rivers

Early curtailment of low assurance of water supply during drought conditions. Frequent communication and consultation

A range of international seasonal forecasts need to be assessed

None available

Industrial demand

Reductions in river flows in the WCWS

Increased recycling along with desalination, introduction of new water efficient technology

Monitoring is adequate

With recycling and desalination, demands for surface water can be brought down by 60% with relative ease

Urban demands


Education and incentives for greater efficiency of use


Demand may be brought down cyclically by 30+% in response to drought conditions. There is reduced scope for efficiency gains

Agricultural users


Greater efficiency in water use. Reduce un-licenced and illegal abstractions

Improved accuracy of abstractions for irrigation purposes is required.

It is possible to bring demand down by 20-30% with careful application of technologies

Bulk water supply to other users - WCWSS


Greater coordination between different tiers of government. Introduce recycling into the system


The introduction of recycling can bring demand down by 30% with relative ease

Fish processing


Use of desalination technologies

Monitoring is adequate, a small user

Desalination can bring demand down by 60%

Commercial forestry


Little scope for change

Land use is already controlled by legislation

No increase in current area under afforestation

Invasive alien trees


Removal of invasive alien species

Annual or biannual satellite and ground-based mapping

Not greater than 15% of riparian and upper catchment land area to be fully invaded

3. Water Quality

3.1 Status of Fresh Water Quality

19

Specific water quality issues face the Saldanha Bay LM. Water quality in the Berg River deteriorates

progressively and substantially downstream, from its source. There are multiple drivers of the poor

quality, which include agricultural activities, urban storm water runoff, fish processing, discharge from

waste water treatment plants and runoff from informal settlements, discharge, leachate and spills

from minerals processing, surface water runoff from port services and the influences from local

geology (Seyler and Millson, 2015a). These impacts are expanded in terms of causes, below:

Figure 6 Influence diagram describing the key components affecting the quality of surface water resources in the WCWSS and the Saldanha Bay Local Municipality.

Eutrophication

Eutrophication is a result of effluent from WWTW, agriculture and winery effluent, fertiliser runoff,

informal settlements, untreated sewage. The influx of nutrients results in algal growth, odours, toxic

algae – blue greens, treatment costs, aesthetics, clogging of pipe infrastructure, health risks to users

(including recreational) (Adams et al., 2018). de Villiers (2007) records that inorganic nitrogen and

phosphorous concentrations have increased in river water by a factor of 10 and that nutrient levels

have fluctuated to levels of more than 1000% natural background levels, far exceeding of the maximum

accepted change of 15% accepted by South African water quality guidelines for aquatic ecosystems.

Dimethyl sulphide (DMS) concentrations are also relatively high (DWS, 2016b). DMS is a volatile

organic sulphur compound, produced naturally by marine algae but in the Berg River system, possibly

by the untreated release of winery and distillery waste directly into the Berg River, possibly from the

Klein Berg River draining the Tulbagh catchments and where the Tulbagh WWTW functions poorly

(Department of Water and Sanitation, 2016). Additionally, some irrigators use winery effluent in close

proximity to the rivers and this is also a possible source of the DMS.

Vandalism and pipe blockages in reticulation systems are also causes of spillages of sewers into the

storm water conveyance systems, which flow directly into the river and bypass the waste water

treatment plants (DWS, 2016b). Hypertrophic conditions occur episodically at all the Berg River water

20

quality monitoring stations, including that at the Misverstand intake point. de Villiers (2007) notes

that the Berg River water quality status is very sensitive to reduced river flow, meaning that as

increased abstraction and utilisation occurs in the upper catchment, so the water quality parameters

in the lower Berg River system will increasingly show negative trends.

Salinisation

Salinisation is driven by high salinities in effluent from WWTW, agricultural runoff, leaching from rocks

(Malmesbury Group), industrial discharges, seawater intrusion (into aquifers). Saline waters results in

higher water treatment costs, irrigators using saline waters risk increasing soil salinity and damage to

irrigation systems through corrosion. Some industries are sensitive to saline intake waters, eg Duferco

monitor incoming water and have registered concerns about the rising salinity and salinity

concentration spikes.

Inorganic pollutants Metals are increasingly noted as pollutants in the Berg River. Iron (Fe) and aluminium (Al) have

increased the most rapidly and comprise the greatest pollutant loading (Jackson et al., 2007).

Manganese (Mn) concentrations have also been shown to be rising rapidly. Mn is a major component

of some pesticides and fungicides (Jackson et al., 2007). Other metal contaminants shown to be

increasing in concentration are copper (Cu), nickel (Ni) and zinc (Zn), all above recommended water

quality guidelines of Department of Water Affairs and Forestry (DWAF, 1996) and the Canadian Council

of Ministers of the Environment Quality Guidelines (CCME, 2001), standards on which water quality

standards were undertaken (DWS, 2016b). Concentrations of lead (Pb) was not shown to be

increasing.

These trends are likely the result of the leaching of these metals into the river water from waste and

household products associated with informal settlements and adsorption onto sediment particles, as

well as runoff from the industrial areas of Paarl. Water quality monitoring sites near the township of

Mbekweni in Paarl and particularly below the industrial area show sharp increases in contaminants.

The highest concentrations are observed at the site just below the industrial area in Paarl where

engineering companies, a tannery, fruit juice manufacturing, waste water treatment and land fill sites

are located (Jackson et al., 2013).

Microbial contamination

Microbial contamination is driven by effluent from WWTW, damaged infrastructure (vandalism),

sewage spills poor management of runoff from settled areas. Results in disease outbreaks amongst

those coming into contact with the water, high BOD and ecosystem effects.

Emerging contaminants

Pesticide and herbicide residues, industrial wastes are increasing problems. These have effects on

human and animal health, serious concern needs to be given to the under-evaluated endocrine

disrupters and various toxins present. See (Walters, 2017) for example.

3.2 Trends driving changes in water quality

For the foreseeable future, water quality in the Berg River system and therefore the water intake at

the Misverstand weir, will continue to decline. Further industrial development in Saldanha will have

to have the salinity concentrations of intake waters as a consideration when establishing plants that

are sensitive to chlorides in their industrial processes. Poor quality irrigation water is already

21

threatening agricultural exports from the Berg River valley. Agriculture here is a key part of the

regional economy/

Berg River - rising urban development, poor storm water quality and the impacts of inter-basin

transfers, inadequate riparian buffers, poor sanitation in informal settlements, high nutrient loading

from agricultural and other influences, invasive alien plants along the riparian zones (wattles and

eucalypts) all contribute to increased stresses of this river system. Sustainability of the whole system

will increase if the recommendations of the Government Gazette (2019) can be implemented.

Breede River – abstractions for agriculture, interference in the riparian zone including agriculture

within the flood zones, nutrient loading, loss of habitat, invasive alien species - aquatic and terrestrial,

and poor quality return flows will increasingly stress this system. The Breede River and

Riviersonderend River are the likely future water supply scheme development options after all possible

and marginal schemes in the Berg River catchment are implemented.

Wetlands – in the WCWSS catchment area – riparian wetlands are largely or seriously modified, in

studies on present ecological state assessments for rivers. This status is unlikely to change, but get

worse as pressure on river systems increases. The SALDANHA BAY LM has relatively few wetlands of

note (see Fig7).

22

Figure 7 Surface water bodies, including dams, wetlands and the Berg River estuaruy within the context of the Saldanha Bay Local Municipality

23

Table 11 Drivers and pressures of poor water quality in the Berg River

Impact Driver Pressure How do the drivers, pressures and impacts interact specifically within SALDANHA BAY LM?

Wat

er Q

uan

tity

Red

uct

ion

Governance – Poor monitoring and control

Poor or absent monitoring practices, collection and evaluation of data, absent reporting results in a lack of control applied to poor water quality situations results in pollution of all the downstream river sections and deterioration of the ecosystem and rising costs for other river users, as well as possible loss of revenue


Reduced flow and flushing services

The amount of water in the river has a direct influence on the amount of water in the system and resulting pollutant loading, low flows are associated with high pollution concentrations and higher water temperatures, causing poor water quality in all parameters

Industrial pollution

Inorganic pollutants, salinisation

Metal and other manufacturing processes with poorly controlled surface runoff and waste water treatment results in metal and other inorganic contamination of the river systems. These contaminants accumulate in the higher trophic orders, such that such that top-level predators in the system are poisoned, including fish that are taken as food sources

Human behaviour

Vandalism, poor maintenance

Releases of raw sewage into the river systems occur when vandalism, theft of metal conveyance infrastructure and breakdowns in the treatment system that result from poor maintenance practices. Substantial eutrophication and microbial contamination then occur. Higher costs for treatment and loss of export of contaminated agriculture goods results

Urban Poorly functioning WWTW

Very poor-quality effluent, with high biological and chemical oxygen demand, is released into the rivers, causing eutrophication, microbial contamination. Higher costs for treatment and loss of export of contaminated agriculture goods results. A large majority of WWTW operate below standard

Informal settlement

Eutrophication, microbial contamination

Exceptionally poor or non-existent sanitation services as well as uncontrolled stormwater control results in immediate release of highly contaminated water into the river systems, with eutrophication, microbial and pathogenic contamination and inorganic pollution resulting. Higher costs for treatment and loss of export of contaminated agriculture goods results.

Agricultural runoff

Eutrophication, salinisation

Excess fertiliser applications result in nutrient-enriched waters reaching the river systems, causing eutrophication. Poor irrigation practices and irrigation return flows result in saline waters entering the river systems.

Winery effluent

Eutrophication At specific times of the year, poorly controlled winery waste waters reach the river systems, causing spikes in highly nutrient enriched waters to reach the river systems, resulting in high biological oxygen demand, depauperate biota in the river system and impoverishment of the productive capacity of the river systems.

Excessive abstraction

Reduces buffering flows

As water demand and competition for water increases, along with inclement weather – high temperatures and drought conditions, illegal abstractions of water in the system increase. Pollutant loading however does not, meaning an effective rise in pollutant concentrations in the river water.

24

Table 12 Important ecosystem services that result from good fresh water quality in the greater Western Cape Water Supply System

CATEGORY ECOSYSTEM SERVICE

Provisioning

Contributes to human well-being through safe water provisioning for human and animal drinking, cleaning (health provisioning).

Maintains a productive aquatic biota through plentiful sunlight supporting photosynthesis in the water column, fish reproductivity

Regulating High-quality water provides a significant buffering function to pulses of lower-quality water

Supporting High water quality (oligotrophic systems) supports more diverse aquatic biota – fauna and flora. High quality water supports economic activity

Cultural High-quality water is of the essence of human enjoyment of water environments – clear water implies cleanliness, healthy systems, safety, a lack of odours and scenic attractiveness, ie a pleasant environment for recreation

3.1 Risk Assessment – Water Quality

The process of assessing water quality risks is similar to that for water quantity. The same likelihood

rankings are used for water quantity; however, a different consequence ranking is appropriate for

water quantity. The increase in proportion of pollutants is on a substantially different scale to that of

water quantity because it is easy for pollutant loadings to reach several multiples of the pristine

background concentrations.

Table 13 The consequences terms of reduction in river water quality in the Berg River as part of the WCWSS

Consequence Term Consequences of loss of river water quality

Slight >10% increase in contaminants above normal range Little to no alteration of regional aquatic ecosystems, well within natural variability, within the absorptive, adaptive and restorative capacity of the natural aquatic ecosystems, no appreciable concerns by various river water users, no extra expenses by water users for additional treatment, no human and animal health events attributable to declining water quality and specific contaminants

Moderate > 33% increase in contaminants above normal range Some alteration of regional aquatic ecosystems, sill within natural variability with occasional excursions outside of the absorptive, adaptive and restorative capacity of the natural aquatic ecosystems, occasional appreciable concerns by various river water users, occasional extra expenses by water users for additional treatment, no human and animal health events attributable to declining water quality and specific contaminants

Substantial >100% increase in contaminants above normal range Appreciable alteration of regional aquatic ecosystems, appreciably outside natural variability, outside the absorptive, adaptive and restorative capacity of the natural aquatic ecosystems, with visible effects on aesthetics of the river water, registered concerns by various river water users, extra expenses incurred by water users for additional treatment, human and animal health events attributable to declining water quality and specific contaminants

Severe >200% increase in contaminants above normal range Strong alteration of regional aquatic ecosystems, strongly outside natural variability, outside the absorptive, adaptive and restorative capacity of the natural aquatic ecosystems accompanied by die-offs and die-backs of riparian and aquatic fauna and flora, with highly visible effects on aesthetics and appreciation of the river water, including foul odour emissions, very frequent registered concerns by various river water users, substantial extra expenses incurred by water users for additional treatment, frequent human and animal health events attributable to declining water quality and specific contaminants

Extreme >500% increase in contaminants above normal range

25

Widespread alteration of regional aquatic ecosystems, strongly outside natural variability, outside the absorptive, adaptive and restorative capacity of the natural aquatic ecosystems accompanied by die-offs and die-backs of riparian and aquatic fauna and flora, with highly visible effects on aesthetics and appreciation of the river water, including foul odour emissions, frequent registered concerns by various river water users, concerns at national level with agreements for investments in alleviation of the problems, very substantial extra expenses incurred by other water users for additional treatment, frequent warnings by health authorities regarding the dangerous conditions of the river water, along with human and animal health events attributable to the very poor water quality and many contaminants

Table 14 Risk evaluation table for water quality – likelihood, consequences and risk result (EU=Extremely Unlikely, VU=Very Unlikely, NL=Not Likely, L=Likely, VL=Very Likely)

Impact Without mitigation With mitigation

Wat

er Q

uan

tity

Red

uct

ion

Driver Pressure Like. Cons. Risk Like. Cons. Risk

Poor Governance Lack of controls L Substantial High NL Moderate Mod

Climate variation Reduced river flows VL Moderate High VL Moderate High

Industrial pollution Inorganic pollutants L Severe High NL Slight Mod

Human behaviour Vandalism L Severe High NL Moderate Mod

Urban WWTW effluent L Severe High NL Moderate Mod

Informal settlement Poor sanitation L Moderate High L Moderate High

Agricultural runoff Nutrient enrichment L Moderate Mod NL Slight Low

Winery effluent Nutrient enrichment L Moderate Mod NL Slight Low

Excessive abstraction Reduced river flows L Moderate Mod NL Slight Mod

Within the sensitivity assessment (Table 14), low flows in the river implies high concentrations of

contaminants. In some quaternary catchments, some contaminants and indicators of poor water

quality are very high even though good levels are water flows through the system are achieved. See

for example quaternary G10D, Middle Berg river, which has much higher levels of inorganic pollutants

and microbial pollution than is acceptable (that part of the river is rated as Unacceptable with a

category rating of E, when its preferred and managed condition is a D (which still means heavily utilised

by acceptable). The water quality conditions along the Berg River deteriorate downstream, such that

conditions at the Misverstand Weir and in the upper reaches of the Berg River estuary are poor,

especially during low flow conditions, and even worse when very little water flows through the weir to

the estuary, essentially drying its upper reaches. See Government Gazette (2019) for more detail on

the target pollution constituents and loadings.

Table 15 Sensitivity table Water Quality at monitoring nodes (Target Ecological Category TEC data from Government Gazette (2019). Note that proposed TEC is not equivalent to current water quality status, which could be worse than required.

Integrated Unit of Analysis (IUA)

Quaternary Pressure component TEC % nMAR

Sensitivity

Upper Berg G10A Runoff A 98 Low

G10A Runoff C 27 High

Eutrophication High

G10B Runoff - Wemmershoek C 27 Very high G10C Runoff – below BRD D 53 High

Eutrophication

Middle Berg G10C Runoff – below IB Trans. C 366 Moderate

G10D Runoff - Paarl D 89 Low

Eutrophication High

Salinisation High

Inorganic pollutants Very high

26

Microbial contamination Very high

Emerging pollutants High

G10D Runoff D 49 High

Eutrophication Very high

Salinisation Moderate

Inorganic pollutants Very high Microbial contamination Very high

Emerging pollutants Moderate

Berg Tributaries G10E Runoff C 82 Low

G10G Runoff B/C 23 Very High


Microbial contamination High

Lower Berg G10J Runoff D 52 High

Eutrophication Very high Salinisation Moderate

Inorganic pollutants Very high


Emerging pollutants Moderate

G10K Runoff - Misverstand D 51 High


Salinisation Moderate Inorganic pollutants Very high



Berg Estuary G10M Runoff C 52 Very high

Eutrophication Moderate

Salinisation Low

Inorganic pollutants High Microbial contamination High


Best practice management systems need to be applied (Table 15). In this case, they are applied outside

of the SALDANHA BAY LM industrial zone and need to be applied at the WCWSS level of influence. The

SALDANHA BAY LM does not necessarily have an influence over the pollutants entering the Berg River

from the upper catchments to the Misverstand Weir. Nevertheless, the abstraction of water at the

weir for the Withoogte WTW has an influence on water quality in the Berg River estuary as fresh water

flows from this point on are severely impacted.

27

Table 16 Best Practice Management, monitoring and limits of acceptable change for water quality

Impact Driver Pressure Describe best practice management actions

Identify best variables and suitable systems for monitoring

Identify limits of acceptable change

AIR

QU

ALI

TY D

ETER

IOR

ATI

ON

Poor governance

Poor monitoring and control

Current monitoring systems run by DWS are insufficient to meet the requirements of a well-monitored system. Monitoring systems have been withdrawn as a result of lack of resources in DWS Best practice monitoring is at least once a month at all current monitoring points along the Berg River (see Government Gazette, 2019).

The TEC for different segments of the Berg River are listed in Government Gazette (2019)

The Target Ecological Categories (TEC) for each river segment, see Government Gazette (2019) needs to be achieved where excursions from the TEC exist.


Reduced flow and flushing services

Some mitigation by water transfer schemes diluting flows during moderately dry periods, none during very dry periods where all sectors are competing for water.

Climate variation and change is best managed by more strict control and limitations of pollutants reaching the river system.

Limits of change cannot be achieved for this driver of change.

Industrial pollution

Inorganic pollutants, salinisation

Polluters or emitters need to reduce or curtail completely the entry of pollutants into surface waters

Current mitigation systems are inadequate. Onsite (industrial) treatment of waste water and runoff is required.

Frequent sampling is required, point sources of pollutants identified and encouraged to reduce polluted runoff

Human behaviour

Vandalism, poor maintenance

Better protection of infrastructure required, consistent adherence to specified maintenance schedules is required

Performance monitoring of the officials/managers /technicians tasked with maintenance, with consequences for poor performance

Maintenance of systems must be achieved, there are no limits of permissible shortcomings

Urban sources

Poorly functioning WWTW

WWTW need to be brought up to standards and operated consistently at that standard

WWTW are brought back to standard

Investment plans need to be in place and consistent progress made to improve the situation

Informal settlement sources

Eutrophication, microbial contamination

Better sanitation is required, as is storm water management

Sanitation systems are installed, or the settlements are moved into improved housing linked to properly functioning WWTW

Limits of change not applicable.

Agricultural runoff

Eutrophication, salinisation

More precise fertiliser and pesticide

Farming occurs too close to river edges.

Reduce irrigation return flow by

28

applications, larger buffer strips between agricultural lands and riparian systems

More precising dosing of lands with fertilisers and pesticides is required

improved precision of irrigation applications, larger buffer strips provide an ecosystem service in reducing nutrient enriched runoff

Winery effluent

Eutrophication Treatment of winery effluent on site

Winery effluent is recycled onto lands as irrigation water

Limits are the set licence conditions

Excessive abstraction

Reduces buffering flows

Abstractions must be limited to licence conditions

Education, training and monitoring

Regular monitoring, especially in the hot summer months.

4. Trends in Governance

The anticipation of future management of water resources for sustainability assumes good

governance. Currently, because of difficulties in implementation of decentralising decision-making

into the WMAs, as well as a result of skills and finance shortages, the putative Berg and Olifants-Doorn

WMAs have been merged, as have the Breede and Gouritz. However, Water Use Associations (WUAs)

have developed from the old Water Boards into more inclusive entities that manage agricultural water

resources at local levels. Because the Cape Metropole requires water resources from several WMAs

and the WCWSS traverses WMA boundaries, including inter-basin transfers and as water scarcity

increases, increased management integration will be required right across the region into which

Saldanha Bay LM is located. With the management context in mind, adding desalination, for example,

or treatment to higher waste water release standards requires higher levels of management and

governance complexity.

There are ongoing challenges with regard to monitoring. Financial and governance challenges at the

DWS put the question of the quality, accuracy and timeliness and availability of quantity and quality

monitoring data into question.

5. Conclusions - Strategic Perspectives for the Saldanha Bay Region

5.1 Water quantity There is a diminishing amount of water available for further economic development in the region,

unless some strategic decisions are made regarding the differential allocations of water between

agriculture and industry. Some water from surface runoff may become available because of

augmentation schemes at Voëlvlei Dam (including phases 1, 2 and 3) over the next two decades (the

exact timing of which are uncertain although there is a high probability of Phase 1 going ahead in the

next few years. In general, over-abstraction is a current reality which heavily impacts ecosystems and

this effect is noted partly in the degraded quality of the resource. Further industrial development

around should look towards increased levels of recycling and desalination as options for water supply.

The type of industries locating there should also not be of the high water-intensity types.

29

The area of greatest contribution of surface water to sustainable water access for SBLM will be

through recycling and desalination. Desalination should particularly be considered where recycling

can be implemented.

The key risks posed to water quantity in the WCWSS include poor governance, climate variation and

particularly rising somewhat elastic demand by urban users. The risks are not caused particularly by

users in the SBLM but within the WCWSS as a whole. Industrial users pose less of a risk to the system

because they often can recycle more easily; some water quality parameters are not as important to

the industrial user as they are to the urban user. Agricultural users have a lower assurance of supply

and are (or should be) curtailed earlier during droughts and are less of a risk. All of these risks, except

climate variation, can be mitigated with appropriate inputs, investment and high levels of appropriate

governance. The Target Ecological Categories (TEC) of the sections of the Berg River can be met with

careful management with respect to water quantity. However, several tributaries are being utilised

beyond their ecologically sustainable capacity. Achieving the sustainable ecological needs of the

system means less water is actually currently available to the major water users of the WCWSS than at

present. This should focus vulnerable users such as the SBLM on the need to develop other sources of

water, such as improved water recycling and desalination, of which these two solutions should be

specified together.

5.2 Water quality The water quality in the Berg River at the Misverstand Weir continues to decline and, to present, shows

no signs of improving. This decline encompasses rising salinity, biological and inorganic components,

which includes metal contamination. For the near future, these are not going to change much unless

there is significant investment in reducing pollutant loadings at source, much of which will be the

responsibility of government (and not particularly the responsibility of the Saldanha Bay LM). Intake

waters at the Misverstand Weir continue to decline in quality and this has cost and other implications

for economic entities that may be established in the Saldanha Bay area.

The water flowing from the Voëlvlei Dam has fewer challenges (although pollutants in the Klein Berg

River have been observed) but this may change in the future as more supplies are drawn from the

smaller rivers in the area. Monitoring stations are already recording “intolerable” water quality and

less than 10% of rivers and wetlands have water quality rated as ideal. Higher levels of management

input required as negative water quality trends are already having an economic impact in the greater

Berg River area. Export markets are threatening to stop purchases of agricultural goods produced in

this region as contaminant loading on agricultural products increase.

The prime (highest) risks to water quality are posed by poor governance, climate variation, industrial

pollution, negative human behaviour and contaminated urban and informal settlement runoff. These

can all be mitigated to some extent by interventions, noting that such interventions will be outside of

the SBLM. Sections of the river and its tributaries are already shown to be substantially below

acceptable water quality conditions, which have already taken account of impacts of how

developments in the catchment has affected water quality. These Target Ecological Categories (TECs)

have been recently promulgated and show that significant effort needs to be spent on retrieving the

system to a more sustainable level that is less impacted.

Figure 8 provides a graphical summary of the quantity and quality impact assessments. The runoff

component shows the quaternary catchment below the Misverstand Weir, as well as two

subcatchments of tributary catchments has having the highest sensitivity because much of the surface

water in those areas is abstracted for use. During the height of the recent 2015-2018 drought, no

water was let past the Misverstand Weir at times because inflows were so low and there was not

30

enough water to continue supplies to the SBLM. In general, the whole Berg River catchment shows a

high sensitivity to the water abstraction from the river and its tributaries.

Similarly, most of the quaternary catchments have challenges concerning different water quality

parameters. Some quaternary catchments are blank, this is because there are no water quality

monitoring stations in those catchments. Their conditions may be inferred from the quaternary

catchments upstream and downstream of them. Water quality problems in the Berg River catchment

are particularly compromised in the Paarl area as water entering the river there is compromised by all

of the quality parameters in question – eutrophication, salinization, microbial contamination, in-

organic pollutants and emerging pollutants.

Abstraction of water for use along the river reduces the flows and serves to increase the concentration

of contaminants. The challenges of declining water quality in the Berg River system are also closely

related to the declining flow rates in the river and so quality and quantity components of river

ecosystem health are intimately tied together.

Figure 8 A map of the sensitivity of parts of the Berg River catchment, concerning the water quantity and quality parameters including eutrophication, salinization, microbial contamination, non-organic pollution and emerging pollutants

31

6. References

Adams, X., Jones, S., du Preez, D., 2018. State of Environment Outlook Report for the Western Cape Province: Inland Water (No. SRK Report 507350). SRK, Cape Town.

Arcelor Mittal, n.d. Cutting waste, cleaner water. URL https://www.arcelormittalsa.com/thinksteel/index.php/environment/cutting-waste-cleaner-water/ (accessed 6.6.19).

CCME, 2001. Canadian Water Quality Guidelines for the Protection of Aquatic Life. Canadian Council of Ministers of the Environment.

de Villiers, S., 2007. The deteriorating nutrient status of the Berg River, South Africa. Water SA 33, 6. DEA, 2013. Climate Change Implications for the Water Sector in South Africa. DEA&DP, 2016. Western Cape Climate Change Response Strategy Biennial Monitoring & Evaluation

Report. Department of Environmental Affairs and Development Planning, Western Cape Government, Cape Town, South Africa.

DEA&DP, 2013. State of Environment Outlook Report for the Western Cape Province: Inland Water Chapter. Department of Environmental Affairs and Development Planning, Western Cape Government, Cape Town, South Africa.

Department of Water and Sanitation, 2016. Environmental Impact Assessment for the Proposed Surface Water Developments for Augmentation of the Western Cape Water Supply System (Scoping Report No. DWS Report No.: P WMA 19/G10/00/2516/3). Department of Water and Sanitation, Pretoria, South Africa.

DoA, 2016. Drought Relief Scheme 2015/2016: Implementation Plan. Department of Agriculture, Western Cape Government, Cape Town, South Africa.

DWA, 2011. The classification of significant water resources in the Olifants-Doorn Water Management Area (WMA 17). Department of Water Affairs, Government of South Africa., Pretoria, South Africa.

DWA, 2010. Groundwater Strategy 2010. Department of Water Affairs, Government of South Africa., Pretoria, South Africa.

DWAF, 1996. South African Water Quality Guidelines Volume 1: Domestic Use. Department of Water Affairs and Forestry, Pretoria, Pretoria, South Africa.

DWS, 2017a. Determination of Water Resource Classes and Associated Resource Quality Objectives in the Berg Catchment (WP10987): Status Quo Report. Department of Water and Sanitation, Government of South Africa, Pretoria, South Africa.

DWS, 2017b. Determination of Water Resource Classes and Associated Resource Quality Objectives in the Breede-Gouritz Water Management Area: Status Quo Report. Department of Water and Sanitation, Government of South Africa, Pretoria, South Africa.

DWS, 2016a. Support to the Continuation of the Water Reconciliation Strategy for the Western Cape Water Supply System: Status Report April 2016. Department of Water and Sanitation, Government of South Africa, Pretoria, South Africa.

DWS, 2016b. Environmental Impact Assessment for the Proposed Surface Water Developments for Augmentation of the Western Cape Water Supply System (Scoping Report). Department of Water and Sanitation, Pretoria, South Africa.

Government Gazette, 2019. Proposed Classes of Water Resource and Resource Quality Objectives for the Berg Catchment (No. No. 42451), Vol. 641.

Greencape, 2018. Water: Market Intelligence Report 2018. Cape Town, South Africa. Jackson, V., Paulse, A.P., Van Stormbroek, T., Odendaal, J., Khan, W., 2007. Investigation into metal

contamination of the Berg River, Western Cape, South Africa. Water SA 33. https://doi.org/10.4314/wsa.v33i2.49057

32

Jackson, V.A., Paulse, A.N., Odendaal, J.P., Khan, W., 2013. Identification of Point Sources of Metal Pollution in the Berg River, Western Cape, South Africa. Water. Air. Soil Pollut. 224, 1477. https://doi.org/10.1007/s11270-013-1477-5

NDMC, 2016. Annual Report 2015 - 2016. National Disaster Management Centre, Department of Cooperative Governance, Government of South Africa, Pretoria, South Africa.

Pengelly, C., Seyler, H., Fordyce, N., Janse van Vuuren, P., van der Walt, M., van Zyl, H., Kinghorn, J., 2017. Managing Water as a Constraint to Development with Decision-Support Tools That Promote Integrated Planning: The Case of the Berg Water Management Area (Report to the Water Research Commission and Western Cape Government). Greencape, Cape Town.

Seyler, H., Millson, C., 2015a. Water as a Constraint on Economic Development (2014-2015 Research Project Progress Report). Greencape, Cape Town, South Africa.

Seyler, H., Millson, C., 2015b. Water as a Constraint on Economic Development (2014-2015 Research Project Progress Report). Greencape, Cape Town, South Africa.

Talbot, D., 2015. Cheap Water from the World’s Largest Modern Seawater Desalination Plant [WWW Document]. MIT Technol. Rev. URL https://www.technologyreview.com/s/534996/megascale-desalination/ (accessed 7.5.19).

Walters, C.R., 2017. Emerging contaminantsThe drugs we wash away: What happens to antiretrovirals in the aquatic environment? Water Wheel.

Strategic Assessment of Water in the Saldanha LM · Strategic Assessment of Water in the Saldanha...

Documents

Transcript of Strategic Assessment of Water in the Saldanha LM · Strategic Assessment of Water in the Saldanha...