CONSERVING THE WATER FACTORIES OF THE WESTERN CAPE

The Western Cape is critical to any conservation effort in South Africa. It is not only

one of the most ecologically complex and biodiverse areas in the world, (due to the

fact that it is home to more than 70% of one of the World’s six Floristic Kingdoms),

but it is one of the primary water catchment areas for South Africa.

CapeNature, a public entity of the Western Cape Government and mandated with

the conservation of biodiversity in the region, manages most of the mountain

catchments and reserves that supply ecosystem services to its citizens, and the work

that happens here has a direct bearing on the quality of life of millions of people in

the province.

Healthy and functioning ecological infrastructure, that is, our rivers, streams,

wetlands and seeps, in water catchment areas, and acting like “water-holding” and

“water-producing” devices, provides clean, safe water to rivers, dams and ultimately

to the end consumer.

This paper demonstrates how the integrated management of three ecological

processes, namely alien and invasive species, fire and freshwater can be applied

very successfully to conserve and, in many cases, restore these “water factories”.

The Western Cape holds 57% of the strategic water resources in the country, and

90% of the water catchment areas in the Western Cape are managed by

CapeNature. These are typically the mountain catchments contained in a number of

CapeNature nature reserves across the Western Cape, such as the Cederberg, the

Boland and the Outeniqua Mountains.

Figure 1: The strategic water resources in the Western Cape.

Before delving into the actual management and restoration of these “water factories”,

it’s important to highlight a number of threats to this important natural resource and

ecological infrastructure, as well as some case studies of how CapeNature aims to

protect and restore these natural water factories in the Western Cape. It goes

without saying that without water, the Western Cape and its people, and indeed the

whole world, would be a much poorer place.

Figure 2: Where grasslands or shrublands such as fynbos are invaded by alien trees, the overall

water use by the vegetation increases.

To begin, start by looking at a typical mountain catchment in the Western Cape;

primarily covered in our famous fynbos which as a rule, does not really contain any

trees. Normal run-off and water yield from a typical fynbos mountain catchment is

maximised by the fact that a natural and healthy run-off process is maintained.

When trees are added, the situation changes quite dramatically, starting with the fact

that on average, a mature tree, say a pine tree, consumes approximately 40-50 litres

of water per tree per day. In 1995, Dye, Olbrich and Everson established that the

greatest impact on water yield from a healthy mountain catchment area occur when

seasonally dormant vegetation such as fynbos, is replaced by evergreen plants such

as invasive pine trees.

Thus, where grasslands or shrublands (like fynbos) are invaded by alien trees, the

overall water use by the vegetation increases, leaving less water for the streams,

and consequently for the end-user. Furthermore, in 1987, Van Wyk has shown that

infestation by invasive trees can result in a 55% reduction in streamflow (from 600 to

270 mm) in fynbos catchments after 23 years of infestation with pines. This

technically means that the water yield or run-off process has been significantly

affected.

Alien and invasive species

Figure 3: The current estimate is that invasive aliens cover approximately 10 million hectares in South

Africa, and use approximately 3.3 billion cubic metres of water in excess of that used by native

vegetation every year.

The first ecological process in our mountain catchment areas is alien and invasive

species. The current estimate is that invasive aliens cover approximately 10 million

hectares in South Africa, and use approximately 3.3 billion cubic metres of water in

excess of that used by native vegetation every year (that is almost 7% of the runoff

of the country). These estimates indicate that the reduction in water yield is already

significant and definitely large enough to warrant intervention. The logical conclusion

is that these water losses will increase as alien plants invade the remaining,

uninvaded areas.

It is therefore in the interest of healthy catchments and the people of a region that

immediate and decisive action is taken to protect the sustainability of water yield

from South African catchments.

Fire

The second important ecological process in our catchments is fire. Because fynbos

in the Western Cape region is a fire-driven ecosystem, fire remains a very important

and necessary process. Fynbos requires fire to survive and to rejuvenate itself and

without fire fynbos dies!

Therefore, any given fynbos fire is not necessarily bad news; it can be very good

news!

However, every year unwanted and uncontrolled veld and forest fires devastate our

landscapes, affecting natural ecosystem functions, endangering life and ruining

property. With the Western Cape being one of the worst affected areas in South

Africa, it is necessary to pay special attention to fire management within the

mountain catchments of the Western Cape.

Figure 4: With the Western Cape being one of the worst affected areas in South Africa, it is necessary

to pay special attention to fire management within the mountain catchments of the Western Cape.

CapeNature has been mapping fires in the fynbos for many years and over the past

14 years the region experienced 1 139 veldfires, on an estimated 1.2 million

hectares of fynbos. Even though fynbos requires fire, the optimum frequency of fire

needed is in intervals of approximately 10 – 15 years. Add to that the increased fuel

load from invasive alien plants, and the result is that fires in the region are burning

too hot and too frequently and is impacting on the production process of fynbos,

hampering the ecology of the catchment areas for optimum water production.

In an attempt to quantify ecological damage to fynbos by too frequent fires, an

ecological study was done by CapeNature’s scientists in the Boland area in 2009,

following the Western Cape fires of December 2005. Using specific kinds of Protea

species (re-seeders) as indicators, the aim was to establish the impact of the fire on

biodiversity.

Using the established rule and threshold that 50% of the individual Protea plants in a

population should have flowered at least three times before the next fire, the key

finding in 2009 was that there did indeed seem to be a negative impact on

biodiversity in the affected area of six-year-old veld. This was due to the fact that the

Protea indicator species had insufficient time to flower and produce seeds. At least

80% of the Protea indicator species had not produced flowers at the time of the 2009

fire, which means that the plants could not form seed to produce the next generation.

Some of these species need at least 12-19 years before 50% of the plants have

flowered at least once.

In the big January 2013 fires (merely four years later), a large portion of the same

study area burnt, which meant that plants of the indicator species which had

remained, definitely did not have enough time to flower and that biodiversity was

more than likely negatively affected. From a conservation point of view, this is very

worrying.

Freshwater ecosystems

The third ecological process is freshwater ecosystems. Due to the semi-arid nature

of the South African and Western Cape Province landscape, conservation of

freshwater ecosystems has become more and more important. The Western Cape

is fortunate to still have some near-pristine mountain streams and upper foothill

rivers, many of them found in CapeNature Nature Reserves and mountain

catchments. The wetlands found in these mountain catchments are generally also

found to be in good condition.

However, too many of the lower lying ecosystems such as rivers and wetlands in the

rural and mostly agricultural landscape, have been altered to a completely degraded

state, often resulting in impoverished water quantity and quality. When freshwater

ecosystems reach this degraded state, they also lose their ability to act as so-called

“ecosystem services”, that is to, for example, supply freshwater during dry periods or

to mitigate against serious ecological damage during severe flooding events.

Figure 5: Due to the semi-arid nature of the South African and Western Cape Province landscape,

conservation of freshwater ecosystems has become more and more important.

Looking at the state of our Western Cape freshwater ecosystems, and according to

the CapeNature State of Biodiversity Report of 2012, 45% of the province’s rivers

and 71% of our wetlands in the Western Cape are threatened (either Critically

Endangered, Endangered or Vulnerable), compared to 51% and 65%, respectively,

at the national level. Lowland river ecosystem types and floodplain wetlands are the

most threatened river and wetland ecosystem types. This is particularly concerning,

as they are also the least protected of the river and wetland ecosystem types.

In order to assist planning for freshwater conservation, Freshwater Ecosystem

Priority Areas were identified, and it was established that all the indigenous fish could

for example be protected if we were able to protect a mere 17% of rivers in the

Western Cape.

CapeNature takes the management and restoration of our mountain catchment

areas and freshwater ecosystems very seriously and the following case studies and

ways in which we go about it, hopefully will illustrate that we aim to make a

difference.

Case Study 1: Duivenhoks

Figure 6: The Duivenhoks Wetland Rehabilitation Project

Since 2009/10 the Duivenhoks (near Heidelberg) and Goukou (near Riversdal)

Wetland Rehabilitation Projects in the Hessequa Municipality of the Western Cape

have been rated as the best amongst various Wetland Rehabilitation Projects across

the country. These two wetland ecosystems, both palmiet-dominated, peatland

systems, are rehabilitated as they are considered of high value for both biodiversity

and water supply to nearby towns and farms. These two systems have been

impacted on mainly by ill-advised agricultural practices in the past. Many farmers

have for example dug irrigation trenches in the wetlands or drained them for

cultivation. In many cases, crops were cultivated too close to wetlands or even

within their boundaries.

The project started in the Goukou wetland system where a gabion structure was

constructed in the middle of a very sensitive and inaccessible wetland, and which

has been restored to the point where it has withstood some serious flood events

(500 mm in two days) proving that the design and workmanship were up to task.

With the completion of this structure, a new structure was started on the Duivenhoks

system as well. This is a much bigger structure also made of gabions and with

difficult access. Both these projects are deemed successes and the wetlands are

functioning and relatively healthy again.

Case study 2: Berg River Improvement Plan

Figure 7: Berg River Improvement Plan

The Berg River is a vital source of water in the Western Cape, not only for farmers,

but also for industrial development, human consumption, and recreation. In January

2013, the Western Cape Government approved a plan to spend R16 million over the

following three years, on improving the quality of water in the Berg River. The

project is a joint effort between the Western Cape Government, the Department of

Water Affairs, CapeNature and the various municipalities in the area.

This is a multi-faceted project which is aimed at:

• Monitoring water quality: water is being monitored for the presence of heavy

metals, pesticides, pesticide residues, nutrients, as well as E. coli, at 20 sites

identified as critical in the river and estuary areas.

• Upgrading wastewater treatment works: both the Franschhoek and Wemmershoek

wastewater works are being upgraded, in partnership with the relevant

municipalities.

• Upgrading informal settlements alongside the Berg River: looking at how

communities can maintain a healthy state, regulate its own waste and heal its own

water.

• Introducing sustainable practices and the efficient use of water in agriculture: we

are working with famers and golf estates in the riparian zone, on the best and most

efficient use of water.

• Rehabilitation and bioremediation: CapeNature and Working for Water have

undertaken alien vegetation clearing in Hermon, Drakenstein, and near Voëlvlei

Dam, with corresponding planting and bioremediation in these areas.

Also, economies of water: looking at how much water is used by the region’s

economy, where and how it is used, analysing consumption in terms of economic

productivity, and designing and implementing interventions to alleviate constraints.

This is certainly not a short-term plan. The Berg River Improvement Plan is a joint

effort from a number of different agencies who are working together towards a

common goal: that the Berg River will continue to be a valuable and protected

source of water into the future.

Case study 3: Job creation through conservation

Unemployment is a key issue in South Africa; and CapeNature and other

conservation authorities realised that conservation provides opportunities for

employment, particularly in poor communities. Programmes like the Expanded

Public Works Programme, including Working for Water and Working for Wetlands

have provided jobs that play an important part in conserving our natural resources.

People employed in these programmes have been of enormous value in clearing

alien vegetation, building firebreaks and infrastructure, as well as assisting during

disaster situations, for example oil spills and floods.

Figure 8: CapeNature’s contribution to job creation

Figure 8 depicts results obtained by CapeNature over the last few financial years

including the number of jobs and Full Time Equivalents created.

CapeNature managed to make great strides in the past five years with the help of the

Working for Water programme in terms of the management of invasive alien plants

within protected areas. This is perfectly aligned with the Government’s attempt to

create jobs and alleviate poverty, and has made a difference in many people’s lives.

Figure 9: Response to Western Cape unemployment and poverty – deployment of resources

Figure 9 illustrates how the different “Working for…” projects are deployed across

the Western Cape region. The backdrop to these projects is the so-called “poverty

layer” based on the Western Cape demographic statistics and more specifically, the

unemployment per ward. With this approach, it is at least possible to make sure that

some of the effort and money allocated towards job creation and poverty alleviation

is spent in areas where it is most needed.

Looking at the amounts spent in the landscape, these efforts are making a significant

difference in people’s lives.

Case study 4: Integrated fire management

Integrated fire management is the development and implementation of mitigation

measures, standards and prescriptions based on comprehensive risk assessment,

and aimed at reducing the negative impacts of veld and forest fires on social,

economic and environmental assets. It is an adaptive process of continual

improvement, involving record-keeping, monitoring, measurement and modification.

Integrated fire management also implies co-operation and coordination between all

role players in the fire prone environment.

Partnerships between Provincial Disaster Management Fire Brigade Services,

District Municipalities, fire contractors, Volunteer Fire Services and a number of Fire

Protection Agencies, create a distinct effort for cooperation, rapid response and

suppression. Integrated awareness initiatives and monitoring has proven to be

successful during the last fire season (2013/14) with less hectares burnt; in fact, only

one tenth of the area burnt during the previous season, even though there were the

same number of fires.

The Winelands District Municipality is leading the way with a joint Integrated Fire

Management Plan along with CapeNature to ensure better veldfire management

within the Boland Area. This is an area which has been identified as a high risk area

for ecological damage due to too frequent fires.

Case study 5: The Rondegat Rehabilitation Project

The Rondegat rehabilitation project demonstrates yet another way and angle of

ecological restoration of ecosystems that have been affected by alien and invasive

species. A 4.5 km stretch of the Rondegat river in the Cederberg Nature Reserve

managed by CapeNature has been cleaned of invasive small-mouth bass in order

that this part of the river can be re-colonised by indigenous fish such as rock catlets,

redfin minnows and Clanwilliam yellowfish. This project is deemed a big success

and the latest monitoring results by independent scientific consultants have shown a

return of this part of the river to a near-pristine stage, and colonised with all three

species of indigenous fish expected to come back!

A healthy ecological system is healthy and free from “distress syndrome” if it is

stable and sustainable – that is, if it is active and maintains its organisation and

autonomy over time and is resilient to stress.

These case studies confirm CapeNature and the Western Cape Government’s

dedication to the integrated management and restoration, where required, of the

province’s mountain catchments and other ecological infrastructure in order that the

people of the Western Cape can benefit from:

more, cleaner and safer water to the end user,

improved and sustainable farming practices,

reduced erosion of ecosystems and reduced risk of disasters,

better adaptation to climate change, and

the conservation and sustainability of the fantastic biodiversity of the region.