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Transportudvalget 2020-21
L 220 Bilag 22
Offentligt

Lynetten Aqueduct

Consideration of aqueduct for Margretheholm Harbour

Yacht Club Lynetten

19 May 2021

L 220 - 2020-21 - Bilag 22: Henvendelse af 20/5-21 vedrørende etablering af en akvædukt frem for en klapbro, fra Sejlklubben Lynetten

Project

Client

Lynetten Aqueduct

Yacht Club Lynetten

Document

Status

Date

Reference

Lynetten Aqueduct, Consideration of aqueduct for Margretheholm Harbour

Final version

19 May 2021

126592/21-007.855

Project code

Project Leader

Project Director

126592

ir. A.J.T. Luttikholt

ir. R.P. Herrema

Author(s)

Checked by

Approved by

ing. S.J. Wolbrink

ir. A.J.T. Luttikholt MSc

Initials

Address

Witteveen+Bos International Projects B.V.

Leeuwenbrug 8

P.O. Box 233

7400 AE Deventer

The Netherlands

+31 570 69 79 11

www.witteveenbos.com

CoC 58093818

The Quality management system of Witteveen+Bos International Projects B.V. has been approved based on ISO 9001.

No part of this document may be reproduced and/or published in any form, without prior written permission of Witteveen+Bos International Projects

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TABLE OF CONTENTS

1.1

1.2

1.3

INTRODUCTION

General information

Definition of the problem

Witteveen+Bos

2.1

2.2

2.3

2.4

2.5

PRACTICE OF AQUEDUCTS

Appearance

Benefits of an aqueduct

Phasing

Water sealing

Highlighted Aqueducts

2.5.1

2.5.2

2.5.3

Project example Margaretha Zelle

Project example Eco-aquaduct Zweth en Slinksloot

Project example Geeuwaquaduct

3.1

3.2

3.3

3.4

AQUEDUCT FOR THE MARGRETHEHOLM HARBOUR

Introduction to the conceptual design

Construction principle

Benefits

Disadvantage

COST ESTIMATION

CONCLUSIONS

Last page

Number of

pages

APPENDICES

Cost estimate

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INTRODUCTION

1.1

General information

The Yacht Club Lynetten in Copenhagen have asked Witteveen+Bos to assess the feasibility of an aqueduct

design in the Margretheholm harbour knowing the design, cost estimate and time schedule for an aqueduct

prepared by Sejlklubben Lynetten. Witteveen+Bos answer is given in the following including the

characteristics of aqueducts in general. By showing the design of some of the aqueducts constructed in The

Netherlands the pros and cons will become clear. This should explain why in the last twenty years more and

more aqueducts were built in favor of bridges. Were in the early years of aqueduct construction they were

purely built to limit road traffic disruptions, the last 20 years the importance of leisure and recreational

sailing has become more important. With more attention going to recreational sailing the waiting times for

marine traffic became more of an issue. Also, with trade offs being assessed on the entire life cycle span the

movable bridges became less attractive from a cost perspective. In a number of cases the life cycle costs of

aqueducts turn out to be close to the cost of moveable bridges and together with the uninterrupted road

and marine traffic advantage the aqueduct was selected as the preferred option.

The report starts with an overview of aqueducts constructed in The Netherlands. To increase confidence and

show the robustness of the solution itself some specific details with regard to waterproofing are given. By

showing three different construction methods the versatility and applicability is demonstrated. At last a cost

estimate of an aqueduct for the Margretheholm harbour is given.

1.2

Definition of the problem

A new temporary road for transportation of soil to a land reclamation in the Northern part of Copenhagen

will be established. This road towards the land reclamation called Lynetteholmen will cross the current

navigation channel to the Margretheholm harbour as shown in the figure below.

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Figure 1.1 Location of the Lynetteholmen and the construction road

Land Reclamation

Lynetteholmen

Construction road

The developer of the land reclamation and their engineer proposed an embankment for the construction

road and a bascule bridge so there will be access to the Margretheholm harbour. Unfortunately the bascule

bridge has only limited opening hours.

1.3

Witteveen+Bos

Witteveen+Bos is a firm of engineering consultants, established in the Netherlands 1946, with over

1,300 professionals across the Netherlands and 14 branch offices worldwide.

Around the world, both public- and private-sector clients call on Witteveen+Bos to help resolve the

challenges they face. We provide advice to contractors, engineering and architectural firms, energy and

water companies, railway and port authorities, and industry. In the public sector, we work for national

governments, water boards, and provincial and local authorities. Our activities cover the entire chain, from

policy-making and design to contracting and supervising construction. Witteveen+Bos aims to establish

long-term relationships with her clients that enables us to meet their needs and expectations as effectively as

possible while delivering maximum added value.

The many international projects that we have successfully completed over the years are evidence of our

effective expertise and ability to adapt to local requirements. Witteveen+Bos has been involved in the design

of the following aqueducts:

- Margaretha Zella aqueduct (Western ring road Leeuwarden) (paragraph 2.5.1).

- Richard Hageman aqueduct (Leeuwarden).

- M.C. Escher Akwaduct (Drachtsterweg, Leeuwarden).

- Hendrik Bulthuis aqueduct (Bergum).

- Geeuw aqueduct (Sneek) (paragraph 2.5.3).

- A4 Midden Delfland (paragraph 2.5.2).

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Currently Witteveen+Bos is involved in the following projects with similar civil structures:

- Maasdeltatunnel and Hollandtunnel (Rotterdam).

- the Scheldt tunnel (Antwerp).

- Fehmarnbelt tunnel (Denmark-Germany).

- ViaA15 roadway (deepened road way in between sheet-piles).

Infrastructure and Mobility

Deltas, Coasts and Rivers

Civil Structures for Railways

Construction Management

Infrastructural Engineering

Smart Infra Systems

Traffic and Roads

Underground Infrastructure

Ecology

Coasts, Rivers and Land

Reclamation

Flood Protection and Land Development

Hydraulic and Geotechnical Engineering

Ports and Waterways

Water Management

The engineers of Witteveen+Bos worked on a lot of tunnels, viaducts and aqueducts in the Netherlands but

also abroad. Three of these project (A4 Midden Delfland, Geeuwaquaduct and Haak om Leeuwarden) are

highlighted in chapter 2.

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PRACTICE OF AQUEDUCTS

2.1

Appearance

In the Netherlands aqueducts are quite common, especially in the northern part of the country. Due the

number of waterways and lakes and the importance of sailing to the local tourism industry aqueducts are

more and more selected in favor of movable bridges. From figure 2.1 the rapid increase in aqueducts in the

last 10 years is shown.

Aqueducts are mainly constructed at the crossing of roads with canals and small rivers. Large river crossings

are constructed with tunnels for which different techniques (other than aqueducts) are utilised. The main

problem of the canals is not the professional shipping traffic but the recreational traffic. The fixed standing

rigging (mast, or the tall upright post carrying the sails) of those ships would lead to exceptional high

bridges or to an unacceptable amount of bridge openings.

Figure 2.1 Number of aqueducts constructed in The Netherlands

Table 2.1 shows a list with the 10 last build aqueducts. A few of these aqueducts are highlighted in the

following paragraphs.

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Table 2.1 Aqueducts constructed in the last 10 years

Name of the Aqueduct

Dampoort aqueduct

Amstel aqueduct

Limesaquaduct

Margaretha Zelle akwadukt*

Richard Hageman akwadukt*

Aqueduct Steenbergen aan Zee

Eco-aquaduct Zweth en Slinksloot*

Boxemtunnel

Hendrik Bulthuis akwadukt*

Aquaduct Vechtzicht

M.C. Escherakwadukt

Aquaduct Van Harinxmakanaal*

Geeuwaquaduct*

* projects Witteveen+Bos participated

Year of Execution

2011

2014

2015

2016

2017

2008

Usually the ramps of aqueduct are less than 250 m and the closed section of the aqueducts rarely exceeds

50 m. This means that it is not classified as a tunnel and therefore no electrical and mechanical installations

(i.e. ventilation) and emergency egress facilities are required. Needless to say is that a pump sump and

lighting is required.

Aqueducts have been constructed in highways with 2x5 lanes and in local roads with 2x1 lane (and

bidirectional traffic in one tube). The first aqueducts where constructed in highways in the densely populated

western part of The Netherlands. Later on, smaller aqueducts with 2x1 lanes were constructed as well.

A rule of thumb used up to the nineties was that an aqueduct was around 3 times as expensive as an

moveable bridge. Due to increased experience and optimalisations in construction methods a factor of 1.5 is

now used.

Figure 2.2 Large (left) and small aqueduct (right)

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2.2

Benefits of an aqueduct

There are a lot of benefits of building an aqueduct instead of a (movable) bridge, the most important

benefits are summed up below:

- Road traffic is not disrupted (bridge will disrupt road traffic in opened position).

- Marine traffic is not disrupted (bridge will disrupt marine traffic is in a closed position) .

Vertical clearance of vessels/ships/boats is infinite.

Vessels can sail in and out without waiting.

- No fendering works for waiting vessels required.

- No hydraulics needed for opening a bridge.

Reduces amount of maintenance.

No risk of malfunctioning.

- Low visual impact.

- Reduced noise impact.

Disadvantages of aqueducts:

- Water safety. Flooding can occur when the ground level of the hinterland is lower than the water level. In

the unlikely event of leakage of the aqueduct the hinterland will be flooded. A flood barrier or dike

around the entrance will prevent floods in these circumstances.

- Construction cost. The initial investment (direct cost) of building an aqueduct is generally higher than the

cost of building a bridge.

2.3

Phasing

For constructing an aqueduct there are two common methods. The first one is to construct the ramp and the

aqueduct in two phases, for example first constructing the right side so vessels can use the other half. After

finishing the ramp and the aqueduct the vessels can use the aqueduct and the left part can be build. This

principle is shown in the image below. Minor dredging might be required to provided sufficient depth for

the diverted temporary shipping lane.

Figure 2.3 Principle building an aqueduct in 2 phases

When it is not possible to divert the axis of the channel an aqueduct can be made by using an immersed

tunnel. The tunnel element will be transported to the location and sunk in the channel. After the element is

in place the vessels can cross the channel and the ramps can be built on either side.

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Figure 2.1 Principle immersion technique for aqueducts Figure 2.2 Immersed aqueduct in Harlingen

When the immersion technique is utilised the element is usually precast in one of the ramps. No access

channel is required and the transport distance is limited. However, when construction time is important an

aqueduct could be constructed elsewhere. This has however for aqueduct construction never been used.

2.4

Water sealing

One of the most important issues in constructing an aqueduct is water tightness. Water tightness of the

concrete or sheet piles is usually not a problem. Concrete itself is water tight when the usual detailing rules

are applied. Sheet piles can leak through the joint but this can be solved by applying bituminous sealings in

the joints or, in case that’s not working, by welding the joints together. Attention has to be paid to the joint

between the concrete segment, the joints between sheet piles and concrete and the joints between the

aqueduct and the ramps. To assure a waterproof construction a couple of solutions can be used, the most

common used solutions at tunnels and aqueducts are described below.

W9U-profile

When concrete structures are submitted to outside water pressures, in tunnels, cellars, off-shore

reservoirs, etc., the joints between concrete sections are made watertight with water stops. For

normal purposes standard rubber water stop with vulcanised steel strips alongside (type

W9U) can be applied. This water stop will give water tightness between the concrete and the steel strips.

However in practice, caused by shrinkages in the concrete and errors while pouring, in the area around the

water stop the concrete can show fissures, gravel spots and the like. These issues can accommodate water

seeping through the concrete. To prevent this leakage, a special type of water stop is developed type W9UI.

This type of water sealing is most used in underground structures of concrete. In tunnels and deepened road

or train sections constructed from concrete these seals are used. This seal is also used in sealing the joint

between a concrete part and a steel part. Therefore, the steel part of the W9U is welded to, for example, a

sheet pile.

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Figure 2.3 W9U profile in 3D view (left) and in cross-sectional view in structural slab (right)

GINA-profile

The Gina gasket and Omega seal can be used to make the water tight connection between the immersed

aqueduct element and the ramps of the aqueduct. This combination of seals not only allows for sealing but

also for the transfer of the hydrostatic loads and movements between the tunnel ends due to soil settlement,

creep of concrete, temperature effects and if required earthquakes. The designs are generally based on the

expected tunnel lifetime of 100 years. The GINA seal is used as a temporary water seal directly after

immersion of an element. By the hydrostatic pressure the seal is compressed by itself. The omega-profile is

the final water stop and is installed after immersion. In general the combination of GINA- and omega-seals is

not used in aqueduct construction.

Figure 2.4 GINA-profile in immersed elements

Inflatable-seal

A more common method to water tight connect an immersed aqueduct to the ramps of the aqueduct is by

making us of an inflatable seal. The rubber seal is installed on the embankment of the ramp and the first part

of the aqueduct is immersed in between the embankment. After immersion the seal is inflated and a water

tight connection is established. The connection is regarded as only temporarily. The final water stop is

created by applying an omega seal over the joint. This methods has been successfully utilised in aqueduct

construction.

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Figure 2.5 Schematic sketch of inflatable seal (left)

Figure 2.6 Inflated seal on construction site (right)

Stop log recess

A stop log recess can be used for closing the gap between a immersed tunnel and the cut -and-cover part

(embankment of the ramp). A concrete slab surrounded by rubber profiles will be placed in pre-made

recesses. This method guarantees the waterproofness between these elements.

Figure 2.7 Stop log recess

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2.5

Highlighted Aqueducts

In this paragraph three aqueducts are shown which show the versatility of this kind of structure.

Witteveen+Bos has been involved in the design and construction of all of these three aqueducts.

2.5.1

Project example Margaretha Zelle

The aqueduct Margaretha Zelle was part of the project Haak om Leeuwarden. This city in the north of the

Netherlands was struggling with traffic jams almost daily. An additional road was made to connect two

highways. This project contained a lot of viaducts, bridges and also an aqueduct. This aqueduct provides a

crossing from the Johannes Brandsmaweg to the center of Leeuwarden over the Van Harinxmakanaal

without traffic jams due to the opening of a bridge.

As can be seen on the photo’s below two lanes for cyclist

have been included. The inclination for the cyclists has been reduced compared to the inclination for the

road traffic by elevating the lane at the deepest section.

Table 2.2 Haak om Leeuwarden

General information

Overview

Location

Cliënt

Country

Location

Construction completed

Construction type

Google.Maps link

Provincie Friesland

the Netherlands

Leeuwarden

2020

Aqueduct

https://goo.gl/maps/A7EkpdCRw9Lu5yN39

images/pictures: www.google.com/maps / own picture

Construction principle

To construct the aqueduct a sheet pile wall was placed and the ground was excavated. Afterwards an

underwater concrete floor was cast and ground anchors were placed. After establishing a waterproof box ,

the reinforced concrete floors and walls where made. At the channel also a deck was constructed. The

concrete floors and walls secure a waterproof tunnel in the user phase.

The sheet piles are only required temporarily to create a dry environment to built the final concrete

structure. Also the underwater concrete is only required temporarily. For the Margretheholm harbour

aqueduct the sheet piles can be used as final construction and no final concrete walls are required. It

becomes more common to use the sheet piles also in the final phase and let them retain ground and water

during the entire service life. In case aesthetically the sheet piles are unwanted concrete panels are placed in

front of the sheet piles.

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Figure 2.8 Cross-section of the open part of the aqueduct

2.5.2

Project example Eco-aquaduct Zweth en Slinksloot

The construction of the A4 Delft Schiedam motorway includes the construction of a 7-kilometer motorway

that is built below ground level, a 2-kilometer long land tunnel, an aqueduct and a new connection to the

Kethelplein traffic junction. The aim is to reduce the amount of traffic jams at the highway A13.

Table 2.3 A4 midden Delfland Eco-aquaduct Zweth en Slinksloot

General information

Overview

Location

Cliënt

Country

Location

Construction completed

Construction type

Google.Maps link

Heijmans N.V.

the Netherlands

Schiedam

2015

Eco- Aqueduct

https://goo.gl/maps/8XUYnxx9H7YAsZJx8

images/pictures: www.google.com/maps

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Construction principle

At the A4 project the sheet pile wall is not only used in the temporary situation but also in the user phase.

Inside the dry construction pit (formed with sheet piles) a concrete floor is casted anchored with GEWI-

anchors. In this design underwater concrete was not necessary. At the side of the road a cladding is placed

against the sheet piles, this wall provides the fire safety.

Compared to the Margaretha Zelle aqueduct less material is used and therefore a cheaper construction is

obtained. In this design a water tight connection between the structural floor with the sheet piles is required.

Figure 2.9 Section of the open part of the aqueduct

2.5.3

Project example Geeuwaquaduct

This aqueduct was part of a project to upgrade a regional road to a freeway nearby the city of Sneek in the

province of Friesland. The existing drawbridge caused long waiting times for car traffic but also for the boats

and ships. Due to five grade-separated viaducts and an aqueduct the traffic can cross the river Greeuw, a

Railway and other roads without being disrupted.

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Table 2.4 Geeuwaquaduct

General information

Overview

Location

Cliënt

Country

Location

Construction completed

Construction type

Google.Maps link

Provincie Friesland.

the Netherlands

Sneek

2008

Aqueduct

https://goo.gl/maps/75Yed4ZKAbW89J2R6

images/pictures: www.google.com/maps / own picture

Construction principle

To construct this aqueduct the dry pit was made with two principles, one part with a sheet pile wall and the

other part with a foil construction. After creating a dry pit the underwater concrete floor was cast and

ground anchors where placed. After establishing a waterproof box, the reinforced concrete floors and walls

where made. At the channel also a deck was constructed. The concrete floors and walls secure a waterproof

tunnel in the user phase. The sheet piles where pulled after the concrete box was finished and could be uses

somewhere else in the project.

Figure 2.10 section of the Aqueduct

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AQUEDUCT FOR THE MARGRETHEHOLM HARBOUR

3.1

Introduction to the conceptual design

As an alternative to the proposal by By & Havn for a bascule bridge across the navigation channel to the

Margretheholm Harbour, the Yacht Club Lynetten have prepared the present conceptual design for an

aqueduct with ramps. The aqueduct and ramps have the same road alignment as proposed by By & Havn for

the bascule bridge. The ramps down to the aqueduct have a slope of 6 % following maximum gradients

according to regulation for Danish state roads. Witteveen+Bos was asked to review the design of the Yacht

Club and propose potential improvements.

In the design of Yacht Club Lynetten a caission at the location of the fairway is included. A caisson shall only

be used in case the fairway during construction cannot be diverted. In case of the Margretheholm harb our a

temporary diversion of the fairway is possible and therefore a phased construction is preferred. Although the

construction at the location of the fairway shall now be phased it is not believed that the total construction

time

–

being approximately 1�½ year from construction start - is affected.

A 3D-view of the construction principle including all mayor structural parts is given in the figures below.

Figure 3.1 Construction principle for aqueduct in Margretheholm harbour

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Figure 3.2 Construction principle for aqueduct in Margretheholm harbour (longitudinal section)

3.2

Construction principle

For the phasing of the construction it is assumed that the aqueduct is made in two phases as shown in

paragraph 2.3. The ramps for the aqueduct are designed as a Cut-and-cover sections. First the sheet piles

will be driven into the ground of the channel and the soil in between will be excavated. In the next phase the

underwater concrete will be cast and the ground anchors will be places to prevent the floor from floating. To

reduce materials and costs the underwater concrete is only placed at the lowest points of the underpass, at

the higher points of the ramp only a reinforced concrete floor is required.

A reinforced floor will be made on top of the underwater concrete at the lower parts. The sheet piles,

concrete floor will provide a waterproof box. In between the concrete floor and the sheet pile a rubber

profile will ensure water tightness.

The sheet piles are provided with a fire-retardant coating, by applying this principle it is not needed to place

a cladding. Without the cladding it is possible to reduce the width of the aqueduct, this will have a p ositive

effect on the cost. The fire-retardant coating is also used at the Veluwemeer aqueduct in The Netherland as

shown in figure 3.3.

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Figure 3.3 Rire-retardant coating on sheet piles

3.3

Benefits

By choosing an aqueduct and not a movable bridge it would be possible to access the Margretheholm

harbour for vessels and ships without limitation. Also the transport of soil to the Lynetteholmen will not be

disrupted by the opening of a bridge. Due to a limited amount of hydraulic parts in an aqueduct in

comparison to a bridge the risk of failing of the mechanism is reduced.

3.4

Disadvantage

Future use of the aqueduct

The current horizontal alignment and in particular the radius might pose a problem if it is decided to allow

regular traffic in the future. The radius is quite narrow, so there is al possibility it would be a problem to see

traffic in the other direction on time. A solution for this issue is to adjust the horizontal alignment into a

straight alignment (possible since the aqueducts is not required to cross the fairway perpendicular).

Figure 3.4 Horizontal alignment

Due to the fact that the road will only be used as a construction road, barriers and other utilities would not

be needed. By not applying barriers in the design the width of the aqueduct can be reduced to a minimum .

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30 years instead of 100 years

When the cost are compared from a bridge and an aqueduct normally reduced maintenance is a big positive

point for an aqueduct. In the lifespan of 100 years a lot of the movable parts of the bridge should be

replaced so this is an expensive solution. Due to the fact that this is a temporary road this is not that big of

an argument as it would have been if the construction was made for 100 years.

Comparison with Van Harinxma aqueduct

In the figure below the vertical alignment of the Harlingen aqueduct is shown. This aqueduct is wider than

the aqueduct required for the Margretheholm harbour but is perfect to show the construction principle.

On the right side at a relative deep point the concrete box is transferred into an open excavation (with foil to

avoid uplift). On the left side the concrete floor in between sheet piles continues into a deepened section

with a length of 1.50 km.

Figure 3.5 Vertical alignment of Van Hanrinxma aqueduct in Harlingen

At the shallow section the underwater concrete is not present and only a final concrete slab is required. At

the deep sections a final reinforced concrete slab is present on a temporary under water concrete slab.

Concrete panels in front of the steel sheet piles are used for aesthetic reasons. In the Margretheholm

aqueduct the concrete panels can be omitted.

Figure 3.6 Cross-section of shallow sections of Van Harinxma aqueduct in Harlingen

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L 220 - 2020-21 - Bilag 22: Henvendelse af 20/5-21 vedrørende etablering af en akvædukt frem for en klapbro, fra Sejlklubben Lynetten

Figure 3.7 Cross-section of deep sections of Van Harinxma aqueduct in Harlingen

Figure 3.8 Photos of Van Harinxma aqueduct in Harlingen

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COST ESTIMATION

Based on the main required dimensions for road and marine traffic an indicative sketch has been made to

derive to main quantities. Structural dimensions (sheet pile weight, reinforcement rates, concrete thickness

etc) have been estimated based on engineering judgement as no geotechnical nor structural calculations

have been made.

An important difference with a regular aqueduct is the reduced design lifetime. This structure is designed for

30 years (instead of 100 years).

A second important difference with a regular aqueduct is the fact this road in only allowed to be used by

construction traffic. In the design no future use by public traffic has been taken into account. The (rather

steep) slope of 6 % and narrow road profile cannot be adjusted to meet future road design regulations after

the construction period of 30 years.

With reference to appendix I we also believe the aqueduct is more expensive to construct than the simplified

bascule bridge. However, despite the advantages for both road and marine traffic, we also believe the

operational costs differ. An aqueduct has lower operational and maintenance cost and also lower costs of

energy.

As shown in figure 4.1 the bars show higher initial costs for the aqueduct (capex) than the bascule bridge.

Also the moveable bridge electrical component probably needs replacement within these 30 years.

Mechanical installations are uncertain to last for 30 years. This also depends on the frequency of bridge

openings we do not know. Yearly costs for both the bridge and aqueduct are hardly visible at this scale and

level of detail. However as shown with the dotted lines, cumulative costs are slowly closing the gap. That

means at a longer horizon the aqueduct might be cost efficient because of the lower re-investments

(replacement) costs and lower operational expenditures.

In this cost comparison no costs for decommissioning has been taken into account. Both the bridge and

aqueduct have large component and require specialised equipment in case of decommissioning. It is

uncertain if the structure has to be removed or if life extension after 30 years is required. In case the life time

of the crossing is extended to 50 or 100 years the aqueduct will become more cost efficient.

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L 220 - 2020-21 - Bilag 22: Henvendelse af 20/5-21 vedrørende etablering af en akvædukt frem for en klapbro, fra Sejlklubben Lynetten

Figure 4.1 Capex and opex excluding VAT

€

€ .

€

2021 2023 2025 2027 2029 2031 2033 2035 2037 2039 2041 2043 2045 2047 2049 2051 2053 2055

€

2021 2023 2025 2027 2029 2031 2033 2035 2037 2039 2041 2043 2045 2047 2049 2051 2053 2055

Bridge COWI CAPEX + OPEX

Bridge COWI CAPEX + OPEX (cumulative)

Aqueduct CAPEX + OPEX

Aqueduct CAPEX + OPEX (cumulative)

€

€ .

€

€ .

€

€ 8.

€ .

€

€ 8.

€ .

For a more detailed description of all starting points and exclusions reference is made to the first page of

appendix I. An overview of costs is given in table 4.1.

Table 4.1 Estimated cost

Item

Direct costs

Direct costs including allowance

Costs foreseen (including contractors overhead)

Construction costs (including contingencies)

Total investment costs

Cost

12.475.231

14.346.515

18.871.980

22.646.376

25.665.893

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cumulative costs (NPV)

yearly costs (NPV)

cumulative costs (nominal)

yearly costs (nominal)

L 220 - 2020-21 - Bilag 22: Henvendelse af 20/5-21 vedrørende etablering af en akvædukt frem for en klapbro, fra Sejlklubben Lynetten

CONCLUSIONS

On a conceptual level the options of constructing an aqueduct in the Margretheholm harbour are evaluated.

An underwater concrete slab in between two rows of sheet piles seems the best solution for constructing an

aqueduct. On the underwater concrete a structural floor is cast. Both floors are connected with the sheet

piles and anchored with GEWI-piles. As the fairway can be temporarily diverted no use needs to be made of

a caisson.

Although this structure seems new for Denmark, the different parts utilised in the design have all been used

in other projects in Denmark. Engineering firms, design institutes and contractors are familiar with the design

of the parts although they have never used them together in aqueduct construction. Therefore, the overall

risk of aqueduct construction is considered to be lower compared to moveable bridges were the electrical

and hydraulic installations complicate design.

The construction costs of an aqueduct are higher than the construction costs of a movable bridge. However,

due to the low operational cost and maintenance cost (compared to a moveable bridge) the total costs after

30 years are more or less similar.

At this conceptual level it cannot be concluded which construction is more cost efficient. What can be

concluded is that an aqueduct shall be taken into account when comparing alternatives. With the additional

benefits associated with an aqueduct this option shall be taken into account when making the trade off. A

moveable bridge in front of a marine full of pleasure yachts seems, at least in The Netherlands, as an illogical

solution.

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Appendices

L 220 - 2020-21 - Bilag 22: Henvendelse af 20/5-21 vedrørende etablering af en akvædukt frem for en klapbro, fra Sejlklubben Lynetten

APPENDIX: COST ESTIMATE

Witteveen+Bos | 126592/21-007.855 | Appendix I | Final version

L 220 - 2020-21 - Bilag 22: Henvendelse af 20/5-21 vedrørende etablering af en akvædukt frem for en klapbro, fra Sejlklubben Lynetten

Client:

Project:

Copenhagen Yacht Club

Aqueduct review Margretheholm Harbour

Colofon

Price level:

Version:

Status:

2021

Final

Date:

Project code:

Author:

18-5-2021

126592

SCHE4

PROJECT:

ESTIMATE CLASS

AQUEDUCT REVIEW MARGRETHEHOLM HARBOUR

CLASS 5 CONCEPT SCREENING

Scope description and basis of estimate

Methodology and assumptions:

- Deterministic estimation of investment costs

- No technical drawings are available. Quantities are based on a sketch and the main required dimensions

- Private road (construction traffic only)

- Lifespan 30 years

- Road slopes allowed for 6 %

Risks:

- Risks are not quantified (probability x impact), no risk sessions are held. However, in the

cost estimate a contingecy of 20 % is included to cover technical risks.

- No additional contingency is included for project related risks, like: legal, organisation, political or financial risks.

The aim of this quick cost estimate is to compare alternatives. Differences are quantified for

comparison purposes only.

Exclusions:

Construction costs

- Barriers, asphalt (not required)

- Soil or groundwater contamination (e.g. PFAS,

asbestos etc.)

- Unexploded Ordnance (UXO)

Real estate

- Land plot acquisition

- Site clearance

- Claims due to urban planning decision

Remaining costs

Engineering

- Surveys (bathymetry, geotechnical, environmental)

- Relocate underground utilities (if any)

- Permitting

- Insurances (CAR)

Life cycle costs / OPEX

- Winter road maintenance (e.g. gritting rock salt)

- Decommissioning (end of life)

- Interests

Other (scope) exclusions

- Uncertainty reserve (e.g. P50 > P95)

- Reserve scope changes

- Costs most economical advantageous tender (MEAT)

- Financial costs

- Social costs/benefits (e.g. costs of waiting)

- VAT

Colofon

Project leader:

Project director:

Estimate standard:

Estimate model number:

A.J.T. Luttikholt MSc

R.P. Herrema MSc

CROW Publication137 (2010) www.crow.nl

W+B SSK-2010 Rekenmodel 3.05a (26-2-2020)

1 | 4 Witteveen+Bos | 126592 | Final 01

L 220 - 2020-21 - Bilag 22: Henvendelse af 20/5-21 vedrørende etablering af en akvædukt frem for en klapbro, fra Sejlklubben Lynetten

Client:

Project:

Copenhagen Yacht Club

Aqueduct review Margretheholm Harbour

Project summary

Price level:

Version:

Status:

2021

Final

Date:

Project code:

Author:

18-5-2021

126592

SCHE4

code

description

Known

Direct cost

Known

Direct cost

Preliminaries

Indirect

cost

Contingency

Total

INVESTMENT COSTS (by category)

BK01

BK02

BK03

BK04

OBK

Construction costs Dike with movable bridge (estimated by Cowi)

Construction costs Aquaduct (by Sejlklubben)

Construction costs Aquaduct (W+B, quick&dirty)

Construction costs Aquaduct (by Sejlklubben) reviewed by W+B

TOTAL CONSTRUCTION COSTS

TOTAL REAL ESTATE

TOTAL ENGINEERING

TOTAL REMAINING COSTS

€

12.475.231

3.019.517

€

1.871.285

€

4.525.465

€

18.871.980

3.019.517

€

3.774.396

€

22.646.376

3.019.517

INV

OORINV

SUBTOTAL INVESTMENT COSTS

Project related contingencies

INVESTMENT COSTS DETERMINISTIC

€

15.494.748

€

1.871.285

€

4.525.465

€

21.891.497

€

3.774.396

and

40%

17%

€

M€

25.665.893

35,9

€

15.494.748

€

1.871.285

€

4.525.465

€

21.891.497

€

SINV

Skewness

INVESTMENT COSTS PROBABILISTIC (Mu-value)

€

excluding

€

M€

21.891.497

15,4

€

BTW

VAT

INVESTMENT COSTS EXCLUDING VAT

Bandwidth: with 70% certainty investment costs excluding taxes lie between

Variation coëfficiënt (estimated)

Risks in relation to known costs

2 | 4 Witteveen+Bos | 126592 | Final 01

L 220 - 2020-21 - Bilag 22: Henvendelse af 20/5-21 vedrørende etablering af en akvædukt frem for en klapbro, fra Sejlklubben Lynetten

Client:

Project:

Sub-item:

Copenhagen Yacht Club

Aqueduct review Margretheholm Harbour

Aquaduct (W+B, quick&dirty)

Price level:

Version:

Status:

2021

Final

Date:

Project code:

Author:

18-5-2021

126592

SCHE4

code

WAAR

description

quantity

unit

unit rate

total

INVESTMENT COSTS

400310

400320

400330

400340

400350

400360

400370

400380

400390

400400

400410

Substructure

Aquaduct

Supply and install permanent sheet piles 136 kg/m²

Supply and install permanent sheet piles 169 kg/m²

Fire resistant coating

Temporary sheet piles 150 kg/m²

Supply and install girders

Supply and install steel struts

Supply and install GEWI-anchors, length 24 m

Supply and install GEWI-anchors, length 26 m

Supply and install tremie slab, thickness 1 m

Total Substructure

4.080,00

6.800,00

3.400,00

5.929,31

3.400,00

428,00

35,00

120,00

114,00

3.925,90

Kopje

m²

pcs

m³

€

400,00

425,00

75,00

310,00

250,00

10.000,00

3.200,00

3.500,00

125,00

9.026.435,44

€

1.632.000,00

2.720.000,00

1.445.000,00

444.698,10

1.054.000,00

107.000,00

349.999,84

384.000,00

399.000,00

490.737,50

500310

500320

500330

500340

500350

Earth works

Aquaduct and ramps

Excavate from building pit

Excavate from building pit ramps

Transportation and placement soil surplus (in nearby reclamation)

Dredge and dispose from access channel

Total Earth works

1.608,20

20.244,40

21.852,60

4.000,00

Kopje

m³

€

5,00

7,50

10,00

313.157,50

€

8.041,00

101.222,00

163.894,50

40.000,00

600310

600320

600330

600340

600360

Concrete works

In situ concrete base slab between sheet pile walls (175 kg/m³)

In situ concrete capping beam (100 kg/m³)

In situ concrete elevated slab aquaduct (200 kg/m³)

In situ concrete exterior walls aquaduct (200 kg/m³)

Dewatering cellar

Total Concrete works

3.367,76

996,00

241,23

170,00

50.000,00

m³

EUR

€

385,00

525,00

610,00

700,00

1,00

2.135.637,90

€

1.296.587,60

522.900,00

147.150,30

119.000,00

50.000,00

700310

700320

Misc

Mechanical and electrical installations pump cellar

Vessel guiding structures and beacons

Total Misc

1,00

120,00

EUR

€

100.000,00

7.500,00

1.000.000,00

€

100.000,00

900.000,00

Direct costs

€

12.475.231

NTD031

Additional items

Direct costs incl. allowance

15,0%

€

12.475.231

€

1.871.285

14.346.515

IK036

IK037

IK038

IK039

IK0310

Non-reoccurring costs (e.g. mob/demob)

Site facilities

Management (by building contractor)

Site organisation (eg. foreman, site managers)

General costs

2,0%

10,0%

8,0%

€

14.346.515

16.641.958

€

286.930

1.434.652

1.331.357

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L 220 - 2020-21 - Bilag 22: Henvendelse af 20/5-21 vedrørende etablering af en akvædukt frem for en klapbro, fra Sejlklubben Lynetten

Client:

Project:

Sub-item:

Copenhagen Yacht Club

Aqueduct review Margretheholm Harbour

Aquaduct (W+B, quick&dirty)

Price level:

Version:

Status:

2021

Final

Date:

Project code:

Author:

18-5-2021

126592

SCHE4

code

WAAR

IK0311

IK0312

description

quantity

unit

unit rate

total

Profit

Risk

Indirect costs ('contractors overhead')

3,0%

2,0%

32%

€

17.973.315

€

539.199

359.466

4.525.465

VZBK

Costs foreseen

€

18.871.980

RBK033

RBK

Contingency

Contingencies

20,0%

20%

€

18.871.980

€

3.774.396

BK03

Construction costs Aquaduct (W+B, quick&dirty)

€

22.646.376

VK03

Real estate Aquaduct (W+B, quick&dirty)

€

EK031

EK032

EK033

EK034

EK03

Detailed engineering contractor

Engineering consultancies (design)

Client's organisation (tendering, permitting)

Site supervision, site management

Engineering Aquaduct (W+B, quick&dirty)

4,0%

16%

€

18.871.980

€

754.879

3.019.517

OK031

OK033

OBK03

Permits, insurances

Taxes, import duties etc

Remaining costs Aquaduct (W+B, quick&dirty)

0,0%

€

18.871.980

€

INV03

Total investment costs Aquaduct (W+B, quick&dirty)

€

25.665.893

4 | 4 Witteveen+Bos | 126592 | Final 01