City of : Dam Levels Report

09 July 2018

DAM STORAGE (%) WEEKLY DAM LEVEL CHANGE (%) AVG DAILY WATER USAGE (FOR THE PAST WEEK) ALL WATER SOURCES (Ml/d)

53.3 5.0 510 increase since last week (Target 450Ml/d)

Water Usage from large dams comprising the Water Supply System

1 400

1 200 1 000 800 600 400

Production (Ml/day) 200

0

15-Jul-15 09-Jul-16 04-Jul-17 25-Jul-13 20-Jul-14

27-Oct-18 30-Apr-18

21-Jan-14 16-Jan-15 11-Jan-16 05-Jan-17 29-Jun-18

22-Mar-14 17-Mar-15 11-Mar-16 06-Mar-17 01-Mar-18

22-Nov-13 07-Sep-16 06-Nov-16 02-Sep-17 01-Nov-17 31-Dec-17 23-Sep-13 18-Sep-14 17-Nov-14 13-Sep-15 12-Nov-15 28-Aug-18

21-May-14 16-May-15 10-May-16 05-May-17 Average Production (Ml/day) Date

Western Cape Water Supply System (WCWSS) weekly drought monitoring

This graph depicts total dam storage against potential system risk scenarios.The previous graph monitored the dam level draw down against the 2017 rainfall conditions under different restriction levels.

Danger Zone: Less than average rainfall; system failure less likely in next year but need to manage demand closely Critical Zone: Less than average rainfall; Potential system failure Failure Zone: Worst rainfall conditions; System failure likely Water stored in major dams comprising Western Cape Water Supply System (WCWSS)

STORAGE MAJOR DAMS CAPACITY % % % % % % Ml 09 July 2018 Previous week 2017 2016 2015 2014 BERG RIVER 130 010 83.1 78.7 37.1 45.9 60.2 100.4 STEENBRAS LOWER 33 517 55.5 52.1 28.5 42.5 55.3 85.4 STEENBRAS UPPER 31 767 99.8 101.7 65.4 82.0 65.8 98.8 THEEWATERSKLOOF 480 188 39.0 34.7 19.5 39.2 55.3 102.1 VOËLVLEI 164 095 51.4 42.0 19.8 36.5 40.0 88.4 WEMMERSHOEK 58 644 83.3 79.0 35.6 58.0 52.9 94.0 TOTAL STORED 898 221 478 854 433 903 225 750 382 007 480 010 881 153 % STORAGE 53.3 48.3 25.1 42.5 53.4 98.1

NOTES: 1) Capacity of the major dams of the Western Cape Water Supply System is 99.6% and that of the minor dams 0.4% of the combined capacity of the major and minor dams. Kindly note that all the Major Dams show gross capacity.

2) All figures are for 09 July for each year except for those in the second column, which gives the figures for the previous week of this year.

3) The last 10% of a dam's water is difficult to use, the useable water in the dam is approximately 10% less than the dam level.

120 Dam Levels for 09 July 2014-2018 100

80

60

40

20

0 2014 2015 2016 2017 Previous week 09 July 2018

BERG RIVER STEENBRAS LOWER STEENBRAS UPPER THEEWATERSKLOOF VOËLVLEI WEMMERSHOEK

Ten year graph Indicating volume of water stored in major dams Comprising Western Cape Water Supply System (WCWSS)

CITY OF CAPE TOWN DAMS: 10 YEAR GRAPH INDICATING VOLUME OF WATER STORED 1000000

900000

800000

700000

600000

500000

400000

300000

200000

VOLUME VOLUME STORED IN MEGALITRES 100000

0 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49 51 53 WEEK NO 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018

Water stored in minor dams within Cape Town

STORAGE MINOR DAMS CAPACITY % % % % % % Ml 09 July 2018 Previous week 2017 2016 2015 2014 ALEXANDRA () 126 91.9 91.2 45.1 37.8 20.4 100.0 DE VILLIERS (Table Mountain) 243 100.0 89.2 61.1 100.0 66.9 100.3 HELY-HUTCHINSON (Table Mountain) 925 100.0 102.0 99.8 100.2 75.0 100.3 KLEINPLAATS (Simon's Town) 1 368 71.1 63.5 38.2 52.8 28.7 100.0 LAND-EN-ZEEZICHT () 451 98.8 93.8 65.6 29.4 0.0 0.0 LEWIS GAY (Simon's Town) 182 98.7 100.9 50.7 16.5 85.7 100.9 VICTORIA (Table Mountain) 128 95.0 81.0 100.0 43.0 38.9 101.5 WOODHEAD (Table Mountain) 954 94.3 100.9 85.7 79.9 67.3 72.3 Water usage from large dams comprising the Western Cape Water Supply System

350.0 AVG DAILY PRODUCTION Cumulative Weekly Usage from WCWSS vs Restricted Usage Targe (excludes own WCWSS LARGE DAMS sources) ONLY (Ml/d) 300.0

250.0 473

200.0 Usage Target: 174.7 million (45% of unrestricted usage) 150.0

Current % Savings

100.0 Cumulative WeeklyUsage (MCM) 50.0 41% 0.0 (Target = 45%)

Water Usage DWS Restricted Target Actual (MCM) Prior 5 Year Usage (unrestricted) Planned Usage (Restricted)

The above graph tracks (CCT) water usage against the Department of Water and Sanitation (DWS) restriction requirement against our unrestricted demand (or past usage).

Water Quality Sample Pass Rate

Month Water Quality Compliance (%) Target (%) May-17 99.71 98 Jun-17 99.65 98 Jul-17 99.62 98 Aug-17 99.59 98 Sep-17 99.57 98 Oct-17 99.49 98 Nov-17 99.44 98 Dec-17 99.43 98 Jan-18 99.38 98 Feb-18 99.38 98 Mar-18 99.26 98 Apr-18 99.20 98 May-18 99.07 98

Notes: This table shows CCT drinking water quality compliance according to the South African National Standard 241:2015. Compliance, measured against all prescribed chemical and microbiological components, consistently exceeds the very high CCT target of 98%. (Overall compliance percentages of continuous sampling and analysis are released on a monthly basis. The latest available is for May). Rainfall

Jul RAINFALL (mm) 02-Jul 03-Jul 04-Jul 05-Jul 06-Jul 07-Jul 08-Jul Total* LT Average Blackheath Upper 4.0 0.0 0.0 0.0 0.0 0.0 0.0 19.0 79.4 Brooklands 4.5 0.0 0.0 0.0 0.0 0.0 0.0 16.5 137.2 Newlands 12.5 0.0 0.0 0.0 0.0 0.0 0.0 72.5 271.5 Steenbras 2.9 0.0 0.0 0.0 0.0 0.0 0.0 30.1 140.4 Table Mountain (Woodhead) 5.5 0.0 0.0 0.0 0.0 0.0 31.5 230.2 Theewaterskloof 5.2 0.0 0.0 0.0 0.0 0.0 0.0 43.9 73.1 5.2 0.0 0.0 0.0 0.0 0.0 0.0 33.9 82.8 Voëlvlei 17.0 0.0 0.0 0.0 0.0 0.0 0.0 57.0 93.3 Wemmershoek 9.7 0.0 0.0 0.0 0.0 0.0 0.0 56.7 159.6 Wynberg 10.0 0.0 0.0 0.0 0.0 0.0 0.0 65.0 205.7

Notes: *Total/cumulative rainfall for month indicated above LT: Long Term