CAPE TOWN WATER RESILIENCE

Peter Flower - Water and Sanitation Department

23 June 2017

Presentation Outline

1. Infrastructure and water use

2. Management of current drought situation

3. Contingency planning

4. Accelerated water supply schemes

Bulk Water Infrastructure

• Dams (DWA & City) 15

• Water Treatment Plants 12

– Production Capacity 1650 Ml/day

– Current Capacity Utilisation 45 %

• Bulk Reservoirs 24

– Storage Capacity 2740 Ml

– Average demand storage 3 days

– Peak demand storage 2.5 days

• Pipelines Bulk 655 km

Reticulation 11,000 Km

• Water Allocation and Demand

– Allocation from System 400 Mm3 p.a.

– 2014/15 Demand 345 Mm3 p.a.

– 2015/16 Demand 330 Mm3 p.a.

– Projected 2016/17 Demand 280 Mm3 p.a.

Water Reticulation System

4

• 9,300km of sewer pipeline

• 11,000km of water pipeline

• 650,000 service connections

• 821 staff fixing leaks daily

• 800+ service requests daily

Comparative Water Use from WCWSS (2014/2015)

Cape Town:

345 Mm3/a

(64%)

Other

municipalities:

37 Mm3

(7%)

Agriculture:

158 Mm3

(29%)

Water Use in Cape Town (2015 / 16)

Houses , 55.6%

Flats & complexes,

9.2%

Domestic other, 1.8%

Informal Settlements, 4.7%

Retail & Offices, 11.0%

Industry, 3.9%

CCT Departments & Council-owned premises,

5.2%

Government, 2.5%

Other, 6.2%

70 % Residential

Population Growth and Water Use Efficiency

0.0

1.0

2.0

3.0

4.0

5.0

6.0

0

100

200

300

400

500

600

700

1950 1960 1970 1980 1990 2000 2010 2020

Po

pu

lati

on

(m

illio

ns)

Wat

er T

reat

ed p

er y

ear

(mill

ion

m3)

Water Treated Population Expon. (Population)

City’s demand-side

programme has

‘flatlined’ consumption

since 2000

Water Allocations and Actual Demand

Allocation from Berg

River Dam (84 Mm3)

Fully Financed by CCT

Combined allocations from Voelvlei,

Wemmershoek, Theewaterskloof and Steenbras

Dams plus Palmiet Transfer (320 Mm3)

Proposed COCT Augmentation Schemes

Accelerated Programme

(Additional 15 Mm3)

280- 260 Mm3

20 % Saving

Dam Storage Change and WTP Production – 19 June 2017

WCWSS Reconciliation Strategy Previous long-term planning as at 2016, now being updated.

30%

15-20%

62%

75%

WCWSS Storage Record

45-50%

City of CT dams - 20 year volume of water stored

Updated since recent rains in June

Proposed Full Domestic and Business Water Tariffs (2017/18)

Tariff Step (KL)

Level 1 (10%)

Level 2 (20%)

Level 3 (30%)

Level 4 (40%)

Step 1 (0 - 6)

4.56 4.56 4.56 4.56

Step 2 (6 - 10.5)

17.75 17.75 17.75 17.75

Step 3 (10.5 – 20)

20.77 22.85 24.93 25.97

Step 4 (20 – 35)

30.76 37.22 41.53 43.69

Step 5 (35 – 50)

38.00 51.30 70.29 113.99

Step 6 > 50

50.12 111.38 238.59 302.24

Commercial & industrial tariffs

18.77 21.82 25.35 27.97

Water Use and Restriction Targets

Target Actual Use (June 16 – May 17)

280 Mm3 287 Mm3 (19%)

600

500

21%

Unrestricted Summer

Proposed

“New Normal” Water Resilience Programme

o The days of plentiful water supply have past. Good rainfall years should be considered anomalous as opposed to drought years

o We must all adapt to water scarcity. This does not mean lower living standards or a diminished economy. The old “water scarcity” must become “enough water”

o The current situation presents an opportunity to build a new relationship with water. We must rethink our over-reliance on surface water and seek to build a Water Sensitive City

o Now is the time to build resilience. It is our collective responsibility

o We need to formulate a new relationship with risk as climate change adds significant uncertainty.

o Ultimately we need to make difficult choices for our future prosperity and seek a coalition of the best minds.

Recommendations for Business Sector

• Conduct regular water audits to understand and reduce your operational and supply chain water footprints.

• Set water efficiency targets and gain the support of your suppliers, customers and staff.

• Build long term resilience and plan for climate change by implementing green building and water sensitive urban design guidelines as well as considering alternate water sources (rainwater harvesting, groundwater, treated effluent, etc)

• Prepare for the possibility of intermittent supply in 2017 and 2018 by ensuring sufficient onsite storage and effective operation of pumping systems.

User Category Required Storage (Water Bylaw – excludes fire and air conditioning systems)

Industrial 8 hours process water requirement

Commercial 70 liters per 100 square meter gross area

Hospitals, Clinics, Old Age Homes 250 liters per bed

Planned New Supply

Scheme Yield

(Ml/day) Description Status Estimated Cost

TMG Aquifer 10 Development of well fields into deep aquifer at Steenbras, Wemmershoek and Theewaterskloof Dams

• Drilling tenders being evaluated • Contract commencement scheduled

for end June 2017. Completion March 2018

R 85 million

Seawater Desalination Package Plant

10 - 20 Primarily for sea water quality data acquisition as well as to improve supply security in Atlantis

• Design underway • Construction tenders to advertised in

July 2017. Completion May 2018

R 250 million

Wastewater Re-use (drinking water)

10 - 20 Treatment of effluent from Zandvliet and Bellville WWTW for direct or indirect injection into bulk water supply system.

• Design underway • Construction tenders to be advertised

in January 2018. Completion June 2018

R 250 million

Cape Flats Aquifer & Atlantis Aquifer

5 Incremental drilling to abstract water from Cape Flats Aquifer plus refurbishment at Atlantis aquifer.

• Consultants to be appointed in June 2017. Completion June 2018

R 50 million

WC/WDM Strategy 100 Intensification of demand management measures: • Water restrictions • Pressure management • Water saving incentive schemes • Regulation of plumbing fittings and

water using appliances • Informative water billing • Communication

• Level 4 restrictions effective June 2017 • Network pressures are being across the

metropolitan area

R 10 million

Voelvlei

Augmentation

(Phase 1)

60 DWS Scheme – Pumped transfer of water from Berg River to Voelvlei Dam

• Comment period for EIA closed. R 300 million

Note this is ‘work in progress’. Total new supply is being significantly added to beyond the below. See City media releases for regular updates on this.

Future Water Outlook

• Key considerations:

– Growing regional demand and competition for water

– Climate change requires diversification of water sources and improved water

use efficiency

– Unit cost of water is likely to increase as more costly alternatives to surface water

schemes are implemented

– Opportunity provided by current water crisis must be maximized to effect

“quantum leap” change to the way water is resourced and utilized in CT.

• Drive towards Cape Town as a Water Sensitive City that:

– Optimises and integrates the management of all available water resources –

surface, ground, wastewater and stormwater - to improve resilience

– Places high value on water and strives to increase water use efficiency through

water sensitive urban design

The Future Cape Town – a Water Sensitive City

Thank You