Current meters Tide gauges Figure 1

Current speeds incoming tide spring tide July cm/s 85 cm/s 20 cm/s Figure 2

Current speeds outgoing tide spring tide July cm/s 60 cm/s 15 cm/s Figure 3

Current speeds neap tides July cm/s 35 cm/s 8 cm/s Figure 4

Peak current speeds during river flood 3 Aug 06 Always outgoing 105 cm/s 75 cm/s Figure 5

Average current speeds during river flood 3 Aug 06 Always outgoing 75 cm/s 50 cm/s Figure 6

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22 July 1994 Figure 13

10 December 1996 after Nov 1996 floods Figure 14

10 October 1997 Figure 15

Jan 1999 Figure 16

5 September 2000 Figure 17

28 March 2001 Figure 18

10 October 2002 Figure 19

2003 Figure 20

27 June 2003 Figure 21

6 March 2006 Figure 22

26 July 2006 Figure 23

6 October 2006 Figure 24

estuary flow marina through flow marina local flow Flood tide Ski Canal closed Sea Glades closed This was the situation from ~ 1985 to mid-2002 before Sea Glades Bridge was constructed Figure 25

Flood tide Ski Canal open Sea 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

Flood tide Ski canal open Sea 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

estuary flow marina through flow marina local flow Flood tide Ski Canal closed Sea Glades open This would be the situation if Ski Canal closes again Figure 28

Sand banks in the marina as at 10 June 2006 Upstream of Sea Glades Bridge Figure 29

10 June 2006 Downstream of Sea Glades Bridge Figure 30

10 June 2006 Upstream of Shore Rd Bridge Figure 31

10 June 2006 Around Bird Island Figure 32

10 June 2006 Ski Canal and downstream of Bird Island Figure 33

10 June 2006 Cove Canal Figure 34

10 June 2006 Cove Canal Figure 35

10 June 2006 Cove Canal Figure 36

Effect of tsunami at Port Elizabeth harbour Figure 37

Bird Island 27 June 2003 before Tsunami Figure 38

Bird Island 6 March 2006 after Tsunami Figure 39

Sea Glades Bridge 27 June 2003 before Tsunami; Sea Glades Bridge was opened 27 October 2003 Figure 40

Sea Glades Bridge 6 March 2006 after Tsunami; Sea Glades Bridge was opened 27 October 2003 Figure 41

Tsunami on Sri Lanka coast strong backwash carries sediment seaward Figure 42

Tsunami on Sri Lanka coast strong backwash carries sediment seaward Figure 43

Maintenance dredging of canal to reduce current speed Trim corner even more to reduce turbulence. Erf 1467 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 Erf 2845 Erf 1468 Erf 1363 Erf 1362 Erf 1474