Current meters Tide gauges Figure 1. Current speeds incoming tide spring tide July 06 60 cm/s 85...

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Current metersTide gauges

Figure 1 Figure 1

Current speeds incoming tide

spring tideJuly 06

60 cm/s

85 cm/s

20 cm/s

Figure 2 Figure 2

Current speeds outgoing tide

spring tideJuly 06

40 cm/s

60 cm/s

15 cm/s

Figure 3 Figure 3

Current speeds neap tides

July 06

25 cm/s

35 cm/s

8 cm/s

Figure 4 Figure 4

Peak current speeds during river flood

3 Aug 06Always outgoing

105 cm/s75 cm/s

Figure 5 Figure 5

Average current speeds during river flood

3 Aug 06Always outgoing

75 cm/s50 cm/s

Figure 6 Figure 6

Figure 7Figure 7

1942

Figure 8Figure 8

1961

Figure 9 Figure 9

1975

Figure 10 Figure 10

1978

Figure 11 Figure 11

1985

Figure 12 Figure 12

1987

22 July 1994

Figure 13 Figure 13

10 December 1996after Nov 1996 floods

Figure 14 Figure 14

10 October 1997

Figure 15 Figure 15

Jan 1999

Figure 16 Figure 16

5 September 2000

Figure 17 Figure 17

28 March 2001Figure 18 Figure 18

10 October 2002

Figure 19 Figure 19

2003

Figure 20 Figure 20

27 June 2003

Figure 21 Figure 21

6 March 2006

Figure 22 Figure 22

26 July 2006

Figure 23 Figure 23

6 October 2006

Figure 24 Figure 24

estuary flow

marina through flow

marina local flow

Flood tideSki Canal closedSea Glades closed

This was the situation from ~ 1985 to mid-2002 before Sea Glades Bridge was constructed

Figure 25 Figure 25

Flood tideSki Canal openSea Glades closed

estuary flow

marina through flow

marina local flow

This was the situation from mid-2002 (when Ski Canal opened due to a large southward migration of the estuary inlet) till 27 October 2003 when Sea Glades Bridge was opened

Figure 26 Figure 26

Flood tideSki canal openSea glades open

estuary flow

marina through flow

marina local flow

This was the situation from 27 October 2003 (when Sea Glades Bridge was opened) to the present

Figure 27 Figure 27

estuary flow

marina through flow

marina local flow

Flood tideSki Canal closedSea Glades open

This would be the situation if Ski Canal closes again

Figure 28 Figure 28

Sand banks in the marina

as at 10 June 2006

Upstream of Sea Glades Bridge

Figure 29 Figure 29

10 June 2006

Downstream of Sea Glades Bridge

Figure 30 Figure 30

10 June 2006

Upstream of Shore Rd Bridge

Figure 31 Figure 31

10 June 2006

Around Bird Island

Figure 32 Figure 32

10 June 2006

Ski Canal and downstream of

Bird Island

Figure 33 Figure 33

10 June 2006

Cove Canal

Figure 34Figure 34

10 June 2006

Cove Canal

Figure 35 Figure 35

10 June 2006

Cove Canal

Figure 36 Figure 36

Effect of tsunami at Port Elizabeth harbour

Figure 37 Figure 37

Bird Island 27 June 2003

before Tsunami

Figure 38 Figure 38

Bird Island 6 March 2006 after Tsunami

Figure 39 Figure 39

Sea Glades Bridge 27 June 2003

before Tsunami; Sea Glades Bridge

was opened 27 October 2003

Figure 40 Figure 40

Sea Glades Bridge6 March 2006 after Tsunami;

Sea Glades Bridgewas opened

27 October 2003

Figure 41 Figure 41

Tsunami on Sri Lanka coast

strong backwash carries sediment

seaward

Figure 42 Figure 42

Tsunami on Sri Lanka coast

strong backwash carries sediment

seaward

Figure 43 Figure 43

Maintenance dredging of canal to reduce current speed

Trim co

rner eve

n more

to reduce

turbulence

. Erf 1

467 Maintenance dredging of canal to reduce current speed

Armour banks where water currents are causing erosion

6 March 2006

Widen canal: trim Erf 1473

Maintenance dredging of canal to reduce current speed

Trim corner to reduce turbulence

Erf 1470

Figure 44 Figure 44

Erf 2845

Erf 1468

Erf 1363

Erf 1362

Erf 1474

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