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Westhaven Marina Proposed Pile Berth

Redevelopment Navigation Safety Report

Capt. Jim Dilley, Master Mariner

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Contents INTRODUCTION ....................................................................................................................................... 3

EXECUTIVE SUMMARY ............................................................................................................................ 5

EXISTING SITUATION ............................................................................................................................... 5

Western Entrance/Exit ........................................................................................................................ 5

Navigation at the entrance ............................................................................................................. 6

Area outside the entrance .............................................................................................................. 7

Other traffic .................................................................................................................................... 8

Harbour bridge traffic ..................................................................................................................... 8

Race starts ....................................................................................................................................... 9

Risk assessment .............................................................................................................................. 9

Berthing ......................................................................................................................................... 10

Eastern Entrance/Exit ....................................................................................................................... 10

Navigation at the entrance ........................................................................................................... 11

Pile Moorings .................................................................................................................................... 12

Marina Fairways and Traffic Hubs .................................................................................................... 12

PROPOSED SITUATION .......................................................................................................................... 14

Construction ...................................................................................................................................... 14

Marina Berths ................................................................................................................................... 15

Closure of Western Entrance ............................................................................................................ 15

Vessels affected ............................................................................................................................ 15

Berthing ......................................................................................................................................... 16

Marina fairways and traffic hubs .................................................................................................. 16

Oil spills ......................................................................................................................................... 17

Start box ........................................................................................................................................ 17

CONCLUSION ......................................................................................................................................... 18

Recommendations ............................................................................................................................ 18

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INTRODUCTION

This report discusses potential navigation safety implications that could arise from the

construction and subsequent operation of the redevelopment of Westhaven

Marina, hereafter referred to as the Application. The Application includes an

extension for the western breakwater to connect to the eastern breakwater to

provide public open space and parking. The public open space has been

designed in conjunction with local iwi. The proposal also includes the conversion of

existing pile moorings to pontoon berthage. (see Fig. 1 and the Westhaven Marina

Proposed Occupation Area Fig. 2).

Figure 1. Proposed re-development: Breakwater extension Pontoon berths

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Figure 2. Westhaven Marina Occupation Area

The term navigation safety refers to the safety of a vessel or vessels interacting with:

another vessel or vessels; the seabed; a structure; a natural object, such as rock or

the foreshore; or any combination of the above. As such, as soon as one vessel is

operating in an area, there will be navigation safety issues. Navigation safety issues

may be minimized or reduced to an acceptable level, but cannot be completely

resolved if vessels are operating in an area. Navigational Safety Management is the

system of criteria, standards and competence that maintain the ability of a vessel or

craft to navigate safely in confined waters such as are found in harbour areas. The

most recent occupation permit has addressed this matter to an extent by

delineation a vessel transit area (refer Fig. 2)

The New Zealand Port and Harbour Safety Code (the Code) was introduced in 2004.

The Code brings together a succinct digest of the formal duties and responsibilities

of participants in port and harbour safety and a corresponding statement of the

specific measures appropriate to their fulfilment. A critical component of the Code is

safety management systems based on risk assessment. The Code has been adopted

by the Auckland Council and a Code Application Assessment, Risk Assessment and

Safety Management System has been developed. The assessments and Safety

Management System have been approved by Maritime New Zealand and are

under continual review and audit. The Safety Management System sets out how the

Auckland Council, through the Harbourmaster, manages the safety of navigation.

The risk assessments assist in identifying where possible risk may exist and how control

measures may help in the mitigation of a risk. The Auckland Region Risk Assessment

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and its annual review (the Risk Assessment) (excluding the operation of shipping to

POAL wharves and the operation of RNZN vessels and berths) is undertaken by the

Harbourmaster. Navigation safety issues in the Waitemata Harbour are part of this

Risk Assessment.

EXECUTIVE SUMMARY

The proposed re-development has built on existing good practice and international

standards to provide a practical and effective use of existing space. The increase in

the safety of navigation both within the marina, and in the area immediately to the

north of the marina, is evident.

The only possible adverse effects are a small time inconvenience to some of the

vessels that use the western entrance, and a small percentage increase in traffic

volume at the eastern entrance.

Overall, the proposal provides an appreciable increase in the safety of navigation in

the area and provides for manageable and accessible berthing of vessels. The

possible effects of any construction and ongoing maintenance and dredging work

are easily managed in line with current good practice.

I recommend the movement of the Start Box to the east as suggested in the

proposal.

EXISTING SITUATION

At present, vessels may enter or leave Westhaven Marina through one of two

entrances, the western and eastern entrances (Figs. 3 and 5).

Western Entrance/Exit

The western entrance/exit (hereafter western entrance) is approximately 60 m wide1

(see Fig. 3). On either side of the gap are rock breakwaters, which extend at an

angle underwater thus, reducing the effective width of the channel. The wider

western breakwater has a gangway for access to marina berths on pier A extending

at an angle2 (see Fig. 3). The fairway in the marina adjacent to this entrance is

approximately 60 m wide. The entrance is marked by aids to navigation on both

sides (lights: Oc.G.5m5M and Oc.R.5m5M). There is a tidal flow during the flood tide

through the entrance of approximately 0.2 m/s (0.4 knots).2 Outside the entrance the

flood tide flows west and the ebb tide flows east, at approximately 2 knots.3 There is

1 Proposed Westhaven Pile Berth Redevelopment (Stage 1) Design Report. Beca Ltd 5 August 2015, Fig 1. 2 Ibid., p.10. 3 Chart NZ5323

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an extreme significant wave height through the western entrance of 0.95 m.4 to the

west of the entrance is an area of shallow water (<5 m) marked by a red buoy (see

Fig. 4).

The western entrance provides a route for vessels in the marina navigating to, and

from, destinations to the west in the upper harbour and the start line for yacht races,

which is shorter than using the eastern entrance. Vessels may also use this entrance

to navigate to, and from, areas to the east (the Hauraki Gulf). This is likely to be the

vessels berthed immediately adjacent to the entrance i.e. only the vessels in the

berths of row A and the western pile moorings in the 100 series berths have a shorter

distance to travel using this route rather than the eastern entrance. Once outside

the western entrance, vessels are restricted to a speed of 5 knots within 200 m of the

shore and to 12 knots in the harbour. This speed restriction means that vessels

traveling outside the marina are unlikely to reach a point opposite the eastern

entrance any faster than vessels travelling in fairways within the marina.

Navigation at the entrance

Vessels departing the marina through the western entrance must alter course in the

entrance to avoid the gangway to pier A (see Fig. 3). This line of approach means

that departing vessels may not see vessels entering the marina until level with the

start of pier A (see Fig. 3). Vessels entering the marina through the western entrance

must also alter course in the entrance to avoid the gangway to pier A. Once inside

the marina, vessels navigate between pier A on the right and a line of vessels in pile

moorings to the left. This line of approach means that vessels entering the marina

here may not see vessels departing the marina until level with the start of pier A. In

general, the best practice for passing through a narrow channel is to navigate in a

straight line. This allows vessels to line up an approach to the entrance with a clear

line of sight. Vessels are then able to see other traffic that may be using the

entrance and also are able to judge the effect of tide on the vessel before passing

through the narrow gap. Being forced to make a course adjustment in a narrow

channel introduces more potential for mistakes to be made. In addition, the tidal

flow (0.4 knots) and wave heights (0.95 m)1 will at times cause vessels to have

difficulty in negotiating this entrance.

4 Ibid.

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Figure 3. Western entrance showing passage route in and out on same scale as

figure 5.

Area outside the entrance

Vessels departing the marina through the western entrance emerge into an area of

the Waitemata Harbour approximately 600 m from the Harbour Bridge and 150 m

from the start box for yacht races. The start box is currently situated on the

breakwater between rows C and D (see Fig. 4). This area is subject to strong tides

flowing perpendicular to vessels departing the entrance (the flood tide flows west

and the ebb tide flows east, at approximately 2 knots4).

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Figure 4. Race start box area Start box Harbour Bridge precautionary area

Other traffic

Other vessels in this area include vessels transiting under the Auckland Harbour

Bridge (Harbour Bridge), including bulk carrier ships navigating to and from Chelsea

Wharf, naval vessels navigating to and from Kauri Point Wharf, scheduled ferries

navigating to and from West Harbour, Northcote Point, Birkenhead, Hobsonville and

Beach Haven, superyachts, charter vessels and various recreational craft; yachts

heading toward or positioning at the start line for yacht races (opposite the start

box); seaplanes; and various other small commercial and recreational craft that

may use the area.

Harbour bridge traffic

In particular, vessels exiting the marina at the western entrance come into conflict

with vessels navigating in the vicinity of the Harbour Bridge that may be constrained

because of their draft or air draft. Large vessels, such as ships, superyachts and

ferries can only pass under the bridge between the two northern-most supports (this

corresponds to the highest point of the bridge). This means that large vessels are

navigating to approach a gap of approximately 300 m wide (compared with the

total bridge span that is approximately 980 m wide).

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The centre span of the bridge is 45 m above chart datum. This reduces to 43 m at 76

m either side of centre. Vessels transiting the bridge must have a minimum

clearance of 1 m at the 76 m off centre point. If the clearance is less than 3 m Transit

NZ must be contacted to ensure there is no staging, hosing, or scaffolding under the

centre span. Transits can only be conducted in daylight and all vessels over 80 m in

length must have one tug made fast. A precautionary area surrounds the Harbour

Bridge in which no vessel may impede the passage of a vessel under pilotage, a

warship, a passenger ferry or a vessel over 500 gross tonnes. Shown in magenta on

charts NZ5323 (see Fig. 4) and NZ5322. The western entrance is approximately 150 m

from the start of the precautionary area (see Fig. 4). Thus, vessels using the western

entrance heading west are almost immediately in the precautionary area and in

potential conflict with large vessels restricted in their approach to the Harbour

Bridge.

Race starts

The site of the start box determines the start line, which is approximately 150 m from

the western entrance. Thus, vessels using the western entrance emerge into an area

in which yachts are positioning at the start line during yacht races. Racing yachts

prior to the race start are usually performing many short manoeuvres in a confined

space in an attempt to get to a desired position for the start. This results in many

yachts on different, unpredictable courses, which can cause confusion, especially

for non-racing vessels, resulting in the potential for collisions.

The start line is approximately 200–300 m from the Harbour Bridge. This results in

potential conflict between racing yachts and other vessels navigating in the vicinity

of the Harbour Bridge, particularly commercial ships and ferries. In addition, the

close proximity of the bridge has resulted in racing yachts colliding with the bridge

structure.

Risk assessment

The Auckland Council has a risk assessment matrix for the Auckland region, including

the Waitemata Harbour. This matrix assesses the frequency of an incident occurring

and the consequence if it were to occur. The Auckland Regional Council’s Annual

Risk Assessment Review 20145 for Waitemata ferry operations (Birkenhead to

Westhaven Marina) identifies risks, including risks associated with a commercial ferry

colliding with a recreational vessel, a recreational vessel colliding with another

recreational vessel, a recreational vessel contacting the Harbour Bridge and a

collision as the result of a vessel encountering a yacht race.

5 Auckland Regional Council’s Annual Risk Assessment Review 2014.

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Berthing

The narrow western entrance creates an increased tidal flow [at flood tide of

approximately 0.2 m/s (0.4 knots)].6 This tidal flow can create problems for vessels

mooring or berthing in the area. Tidal flows can cause vessels to speed up, slow

down or push vessels sideways depending on the speed and direction of the flow.

For vessels manoeuvring in a confined space when berthing, external influences

such as tide, and also wind, make it difficult to accurately judge the vessel’s relative

position and speed, which is needed to be able to place the vessel in the berth

without hitting adjacent objects (e.g. other vessels, piles, marina structure).

Eastern Entrance/Exit

The eastern entrance/exit (hereafter eastern entrance) is approximately 270 m wide

(see Fig. 5). On the western side is a rock breakwater and to the east is Wynyard

Quarter and various berthing structures on the western edge of Wynyard Quarter.

The fairway on the marina side of this entrance varies from approximately 130–270 m

wide. The entrance has aids to navigation on both sides (lights: Fl.G.5s5m5M and

Oc.R.6s5m5M). In addition, there is a light on the southern end of the breakwater

around the marina (Oc.G.6s3m). The entrance has a tidal flow during the flood tide

of approximately 0.15 m/s (0.3 knots).6

The eastern entrance is used by most vessels in the marina navigating to, and

from, areas to the east (the Hauraki Gulf), including commercial vessels at Z pier, as

well as vessels from the Silo Park, Orams and Pier 21 marinas and haul out facilities,

the Orams dry stack facility (small boats under 12 m), the dry dock and the refuelling

facility. These vessels include superyachts and other larger vessels using the slipway

and superyacht berths. In addition, there is a proposal to bring the Kiapara Carrier II,

an aggregate carrier of 563 gross tonnes, to a berth within the eastern entrance,

with up to four movements per week. Larger vessels, including the Kaipara Carrier II

and superyachts, will either have a licensed pilot or licenced pilot-exempt master on

board who and will be operating in accordance with the Auckland Council

Harbourmaster guidelines.

With strict guidelines around the operation of large vessels, and a licensed pilot or

pilot exempt master onboard, the movement of these vessel is extremely well

conducted and managed in line with best practice through Auckland Councils

Safety Management System.

Vessel masters may also choose to use this entrance to navigate from the marina to

the west: the upper harbour and the race start line, as this entrance is easier to

negotiate than the western entrance.

6 Proposed Westhaven Pile Berth Redevelopment (Stage 1) Design Report. Beca Ltd 5 August 2015, p.10 and Fig. 2.

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Vessels departing the marina through the eastern entrance emerge into an area of

the Waitemata Harbour approximately 1.2 km (0.6 nm) from the Harbour Bridge.

Other vessels in this area include vessels navigating in the vicinity of the Auckland

Harbour Bridge (Harbour Bridge), including bulk carrier ships navigating to and from

the Chelsea Wharf, naval vessels navigating to and from the Kauri Point Wharf,

scheduled ferries navigating to and from West Harbour, Northcote Point, Birkenhead,

Hobsonville and Beach Haven, superyachts, charter vessels and various recreational

craft; seaplanes; various other small commercial and recreational craft; vessels

approaching the marina, including commercial vessels heading to Z pier, vessels

going to the Silo Park, Orams and Pier 21 marinas and haul out facilities, the Orams

dry stack facility (small boats under 12 m), the dry dock and the refuelling facility.

The greater distance from the Harbour Bridge means vessels departing via this

entrance are less likely to come into conflict with vessels navigating in the vicinity of

the Harbour Bridge than vessels departing from the western entrance.

Navigation at the entrance

Vessels using the eastern entrance pass thorough a wide area with good visibility

(Fig. 5). The width enables a good separation of vessels, even with more than two

vessels in the entrance. A straight line approach to the entrance is possible (in both

directions) ensuring good visibility and with no risks associated with manoeuvring in a

narrow channel.

While the entrance is undoubtly busy at times the width of navigable water,

together with the recently granted Westhaven Marina occupation permit which

identifies a delineated vessel transiting area (see Fig. 2), help manage potential

conflicts between commercial and recreational vessels.

Figure 5. Eastern entrance showing passage route in and out on same scale as figure

3.

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Pile Moorings

There is space for approximately 100 vessels to berth in pile moorings in two rows

inside the marina to the east of the western entrance. The narrow western entrance

creates an increased tidal flow [at flood tide of approximately 0.2 m/s (0.4 knots)].6

This tidal flow can create problems for vessels berthing in the area. Mooring to pile

moorings is particularly difficult as pile moorings do not have pontoons so can be

more difficult to tie up to compared with berths alongside pontoons.

Mooring to a pile mooring requires placing the vessel in a position to pick up four

lines attached to four piles. The vessel is not held in a stable position until all four of

these lines are attached. Any cross tidal flow will make approaching the piles, and

holding the vessel in position while the lines are attached, more difficult.

Marina Fairways and Traffic Hubs

Maritime rule No. 22.9 applies to vessels in a narrow channel and states that ‘A vessel

proceeding along the course of a narrow channel or fairway must keep as near to

the outer limit of the channel or fairway which lies on its starboard side as is safe and

practicable’. Vessels leaving the marina depart from a berth or mooring, move to

the starboard of the channel and then must join the starboard side of the main

fairway, which has a width that varies from approximately 20–80 m. Vessels then turn

at points A (to exit via the western entrance) or B (to exit via the eastern entrance or

access areas to the south e.g. the fuel berth). The areas where any pier or row of

moorings joins the main fairway will have converging and diverging traffic, but the

two main areas where traffic converges and diverges from multiple directions are at

hubs A and B as shown in Fig. 5 These two areas have navigation safety implications

arising from the flow of traffic and the need for collision avoidance.

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Figure 6. Existing areas of traffic convergence/divergence

Hub A is approximately 2800 m2. At hub A, any vessels using the western entrance

and vessels in berths rows A to U using either entrance will converge (see Fig. 7). As

can be seen in Fig. 7, there are multiple points where vessels may cross the line of

another vessel due to the constrained size of the area and obstructions to clear

views caused by the moored vessels. Thus, there is an increased risk of collision at this

point.

Figure 7. Traffic convergence/divergence at hub A for western entrance

Hub B is approximately 7800 m2. At hub B, vessels using the eastern entrance will

converge (see Fig. 8). There are likely to be more vessels navigating at hub B than

hub A. However, it can be seen in Fig. 8 that traffic flow is clearer here, compared

with hub A. and there are less points where the paths of vessels may cross. In

addition hub B is substantially larger than hub A, allowing for more room and better

visibility for navigating vessels. The recently granted occupation permit (see Fig. 2)

manages potential conflicts between commercial and recreational vessels),

providing a delineated vessel transiting area.

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Figure 8. Traffic convergence/divergence at hub B for eastern entrance

PROPOSED SITUATION

The Application includes an extension for the western breakwater to connect to the

eastern breakwater to provide public open space and parking. The public open

space has been designed in conjunction with local iwi. The proposal also includes

the conversion of existing pile moorings to pontoon berthage (see Fig. 1). The new

berths will be built according to Australian Standard AS3962-2001. This in compliance

with best practice in relation to the layout of the piers, marina berths and the access

channels and is used throughout NZ marinas. The access channel between pier A

and the new marina berths will be approximately 40 m, in line with other access

channels in the marina.

Navigation safety implications may arise from the bridging (closing) of the western

entrance, the presence of marina berths where pile moorings are currently located

and the construction of the marina.

Construction

The proposed marina breakwater extension will be formed using dredged material

from the marina using a dredge mounted on a barge. Dredging will be carried out

under an existing maintenance dredging consent held by Westhaven Marina.

Any additional navigation safety issues arising during the construction of the

breakwater and the new marina berths should be similar to the existing issues that

arise during current dredging. In these cases a dredger and associated traffic are

operating within the marina, effectively blocking access ways and restricting access

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to some parts of the marina. There are no reported incidents involving navigational

safety issues with the current dredging or maintenance operations undertaken at

the marina over many years.

These issues should be easily addressed with a Notice to Mariners and, if necessary,

suitable signage to make marina users aware of the issue e.g. dredging and

construction operations.

Marina Berths

The new facilities will cater for approximately 117 new marina berths replacing

space for approximately 125 pile moorings, a slight decrease in vessels using the

space. Some pile moorings will still be available in the marina. Marina berths, with a

pontoon facility, are more user friendly compared with pile moorings, offering with

walk-on, walk-off access and easier berthing. In general, marina berths are more

likely to be used than pile moorings and are a more efficient use of space.

With a pontoon berth, a vessel master has several options for holding the vessel

stable while berthing. The vessel can be brought alongside the berth and a crew

member step off onto the pontoon to hold the vessel or once one spring line has

been picked up, the vessel can steam ahead on the spring to hold position while

the rest of the lines are secured. Alongside the pontoon the vessel can be secured

with only two lines. A cross tide or wind may be helpful in some cases if berthing can

be timed so that the tide is pushing the vessel onto the pontoon when arriving and

off the pontoon when departing.

When entering or departing from a pile mooring a vessel is not held in a secure

position until at least both head line and both stern lines are secure. Further to this

there is no pontoon or similar structure to assist the master in remaining in the correct

position. Pile moorings require a higher level of competence from the vessel master

and are more susceptible to issues with cross tide or wind.

Closure of Western Entrance

Vessels affected

Closing the western entrance will mainly affect vessels in the marina navigating to,

and from, destinations in the upper harbour and the start line for yacht races. These

vessels will have to navigate approximately an extra 0.6 nm to reach a position

opposite the start box going through the eastern entrance. This distance would be

slightly less for vessels that may ‘cut the corner’ of the eastern entrance. This

translates to approximately an extra 7 min travel time (for a vessel traveling at 5

knots). If the start box were to be moved to a position located on the new extension

(shown as X in Fig. 9) as has been proposed, this time reduces to an extra 5 min of

travel.

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Figure 9. Current start box location proposed location

Berthing

Closure of the western entrance will result in a decrease in tidal flow at the entrance

from approximately 0.2 to 0.03 m/s (0.4 to 0.06 knots)6. This will result in a decrease in

cross tide at the berths (whether pile or marina berths) situated where the pile

moorings are currently. The extreme significant wave height will be 0.3 m in the

marina down from 0.95 m previously at the eastern entrance7. Thus, closing this

entrance will make berthing or mooring in the vicinity easier.

Marina fairways and traffic hubs

Traffic at hub A will now only be navigating in two clear directions (see Fig. 10). Like

all pontoon fairways there will be vessels navigating to their berths in each pontoon,

but the volume of traffic will be small and will exclude all vessels that previously

navigated to or from the western entrance. Closing the western entrance will result

in a reduction of risk of collision at point A as traffic will now only be going in two

clear directions on either side of the channel as shown in Fig. 10. This will result in less

confusion at this fairly narrow point and provide a positive effect on the safety of

navigation.

7 Ibid.

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Figure 10.Main traffic flow at hub A with western entrance closed.

With the closure of the western entrance the traffic volume at the eastern entrance

will increase. There will be an increase in traffic at hub B as all vessels will now transit

this area. However, this area is large, already has traffic coming from the direction of

the marina and the traffic flow is relatively clear — the only crossing situation is with

vessels returning to berths to the south of the entrance to the rows of marina berths

e.g. vessels at Z pier or vessels heading to the refuelling facility (see Fig. 8). Any

increase in traffic at the entrance or hub B caused by the closure of the western

entrance is likely to be small in comparison to the normal traffic volume using the

area. Thus, an Increase in traffic at these points is not expected to present any

appreciable navigation safety issues.

Existing issues with potential conflicts between commercial and recreational vessels

at this entrance have been already identified and the risks mitigated, and clear

access further enhanced with the recently granted occupation permit (see Fig. 2),

which provides a delineated vessel transiting area. Vessels entering or departing

Westhaven Marina are required to use the area to the western side of the entrance

as shown in Fig. 2. This provides a clear channel for the use of commercial traffic and

other recreational traffic not berthed in Westhaven Marina.

Oil spills

In an oil spill, one entrance will be easier to manage than two. This means that it will

be easier to protect the marina from an external spill and easier to contain an

internal spill from within the marina.

Start box

Closing the western entrance will allow the start box for yacht races to be moved to

a position on the eastern breakwater as the breakwater will then accessible (see Fig.

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9). This relocation will result in a reduced distance for yachts in the marina to travel

to the start line. Therefore yachts will only have to travel approximately an extra five

minutes to reach the start line exiting through the eastern entrance compared with

exiting through the western entrance. The start line will be moved further away from

the Harbour Bridge. Moving the start line will reduce potential conflict between

racing yachts and vessels transiting under the Harbour Bridge, including bulk carrier

ships navigating to and from the Chelsea Wharf, naval vessels navigating to and

from the Kauri Point Wharf, scheduled ferries navigating to and from West Harbour,

Northcote Point, Birkenhead, Hobsonville and Beach Haven, superyachts, charter

vessels and various recreational craft. Moving the start line away from the bridge will

also reduce the risk of racing yachts colliding with the bridge structure.

CONCLUSION

The proposal to close the western entrance to Westhaven Marina and to redevelop

existing pile mooring areas to pontoon berths appears to increase the level of

navigational safety in most aspects, and provide safer and more easily accessed

and convenient berthing for vessels. The proposal also removes a traffic hub from

the inner part of the marina where vessels may not be expecting large numbers of

vessels crossing a narrow fairway in an area with restricted sight lines.

Furthermore, the proposal also improves the level of navigation safety to the harbour

area north of the western entrance by allowing the repositioning of the yacht race

start box, and removing the flow of vessels entering into the harbour area by the

Harbour Bridge. Both of these will reduce congestion and vessel numbers in the

confined and restricted area of the Harbour Bridge.

There will be an increase in traffic volume at the eastern entrance and the traffic

hub at that area. This will have a slightly negative effect on navigational safety, but

the size of the area, low percentage increase in the traffic volume, clear sight lines,

well-defined fairway areas and the delineated vessel transiting area means we are

unlikely to see any negative impact.

Overall, the proposal provides an appreciable increase in the safety of navigation in

the area and provides for manageable and accessible berthing of vessels. The

possible effects of any construction and ongoing maintenance and dredging work

are easily managed in line with current good practice.

Recommendations

I recommend the Start Box is moved towards the east as indicated in figure 9.