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Newmarket Level Crossing

Multi-Criteria Assessment of Bridge Options

Prepared by:

Public Transport Capital Improvements

2

Newmarket Level Crossing Removal

Document Information

Document Register

Issue Description Prepared by Reviewed by Authorised by Date

001 DRAFT v1 Adrian Price Nesh Pillay Nick Seymour 23 March 2015

002 FINAL Adrian Price Nesh Pillay Nick Seymour 20 April 2015

Client Auckland Transport

Title Newmarket Level Crossing MCA of Bridge Options

Prepared by Public Transport Capital Improvements

Date 20 April 2015

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Executive Summary

Three bridge variants were produced for stakeholder feedback and circulated to the following

groups:

Waitemata Local Board

Mana Whenua

Newmarket Community Groups (Parnell Community Committee, Newmarket Community

Association, Cycle Action Auckland)

Residents and Landowners in Sarawia Street, Cowie Street, Laxon Terrace and Youngs Lane

Workshops and discussions were held involving the designers Opus, Auckland Transport (AT) project

team and AT specialists from Walking and Cycling, Urban Design, Road Safety Engineering, Road

Corridor Operations, Stormwater, Maori Policy and Engagement, Property and Planning, Auckland

Council Sports, Parks and Recreation, KiwiRail and the project Road Safety Auditor (Aurecon).

The Multi-Criteria Assessment (MCA) workshop held in February 2015 concluded with Option 3,

Combined Space, as the preferred option but concerns were raised over the narrowness of the

bridge and the associated potential impact on the interactions of vehicles, cyclists and pedestrians.

Subsequent discussions on alterations to the option were held with AT Road Safety Engineering, AT

Road Corridor Operations, Opus and the Road Safety Auditor and it was concluded that the bridge

width needed to be increased to provide an adequate level of confidence in the traffic safety

outcomes.

Option 4 was developed in response to these concerns, with a separated pedestrian footpath of

1.8m width combined with a two-lane carriageway similar to Option 2. However, it incorporates and

modifies the traffic calming elements of Option 3 through narrowing of the carriageway at entry

points into the new road section, textured paving over the curve of the road as proposed for the

pedestrian-prioritised portion of Option 3, and a pedestrian refuge immediately before the Cowie

Street entrance onto the bridge.

The options were re-evaluated including Option 4, and the conclusion is that while Option 3 remains

first ranking in many criteria, Option 4 provides the best overall outcome while avoiding the

elements prompting safety concerns associated Option 3.

The inclusion of an observation platform on the curve of the bridge was also assessed, with the

conclusion being that this should be included in the bridge design.

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Table of Contents

Executive Summary ...................................................................................................................... 3

Table of Contents ......................................................................................................................... 4

Purpose ....................................................................................................................................... 5

Options Assessed ......................................................................................................................... 5

Option 1: Shared Path Bridge ............................................................................................................. 6

Option 2: Pedestrian Footpath Bridge ................................................................................................ 7

Option 3: Combined Space Bridge ...................................................................................................... 8

Multi-Criteria Assessment ............................................................................................................ 9

Criteria Definitions .............................................................................................................................. 9

Results Summary ....................................................................................................................... 12

Option 4: Optimised Mix of Options 2 and 3 .................................................................................... 13

Base Assessment........................................................................................................................ 15

Sensitivity Assessments.............................................................................................................. 17

Expert Assessed Weightings ............................................................................................................. 17

Specified Category Weightings ......................................................................................................... 19

Monte Carlo Simulation .................................................................................................................... 23

Conclusion ................................................................................................................................. 25

Appendices ................................................................................................................................ 26

Appendix 1: MCA Workshop Minutes............................................................................................... 27

Appendix 2: Newmarket Level Crossing Project – Survey Results .................................................... 34

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Purpose

Three variant options for a bridge linking Cowie Street to Laxon Terrace in Newmarket have been

prepared based on feedback received from stakeholders in 2014.

The purpose is to determine the final bridge footprint and features to be progressed to final

preliminary design via a multi-criteria assessment. Scoring for the assessment has been informed by

the following:

Survey of residents and community groups

Feedback from the Waitemata Local Board

Feedback from Auckland Council Parks, Sports and Recreation

Feedback from Mana Whenua and AT Maori Policy and Engagement

Feedback from KiwiRail

Road Safety Audit for the project

Internal workshop held February 2015 including AT Traffic Operations, Road Safety

Engineering, Walking and Cycling, Planners, Urban Design, Stormwater specialists and Opus

design team.

Subsequent discussion with workshop attendees and the Road Safety Auditor.

Options Assessed

All bridge options share the following features:

Single span bridge over rail corridor beginning at Laxon Terrace and ending at the end of

Cowie Street, through 9 Cowie Street;

Traffic calming area at Cowie Street end of option;

An optional observation platform at the curve of the road, overlooking Newmarket Park

(evaluated separately as part of this MCA);

KiwiRail maintenance access from curve of road towards Parnell tunnel;

Stormwater treatment via vegetated swale located within Newmarket Park; and

Retention of existing Newmarket Park access at Laxon Terrace end.

The following options were initially evaluated:

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Option 1: Shared Path Bridge

This option includes a two-lane carriageway with a 3.0m wide shared pedestrian/cycle path running along one side of the bridge. The carriageway is widest at the Cowie Street end at 6.4m and narrows along the edge of Newmarket Park to 5.0m to join Laxon Terrace.

This option provides the greatest level of amenity for cyclists but also has the greatest impact on the adjoining Newmarket Park land.

Figure 1: Shared Path Bridge

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Option 2: Pedestrian Footpath Bridge

This option includes a two-lane carriageway with a 1.5m wide footpath running along one side of the bridge. The carriageway is widest at the Cowie Street end at 6.4m and narrows along the edge of Newmarket Park to 5.0m to join Laxon Terrace.

This option provides a compromise between separated pedestrian and vehicle movements and bridge width and most closely matches the existing amenity levels at Cowie Street and Laxon Terrace.

Figure 2: Pedestrian Footpath Bridge

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Option 3: Combined Space Bridge

A single combined carriageway and footpath totalling 5.6m width. The bridge width is wide enough for two vehicles to pass along most of the length but periodic buffers spaced approximately 20m apart seek to act as a traffic calming measure and protection for pedestrians. At the buffer points the bridge width is too narrow to permit two vehicles to pass each other, so that one vehicle must give way similar to the action at a one-way bridge or chicane.

This option intends to prioritise pedestrian and cycle movements using the narrow width and buffers and is the narrowest bridge option with least impact on Newmarket Park.

Figure 3: Combined Space Bridge

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Multi-Criteria Assessment

The criteria applied in the assessment are:

Economic:

Capital cost

Renewal/operating costs

Safety:

Traffic safety

CPTED

Environmental:

Stormwater

Landscape/Visual

Ecology

Earthworks

Urban Design

Noise

Cultural:

Maori values analysis

Heritage effects

Social:

Level of service

Wider community impact

Construction impact

Resident feedback

Criteria Definitions

Economic:

Capital cost: Cost estimates vary mainly due to size of the structure and amount of materials

required and surfacing differences between options. Cost estimates for each option are

based on the road, bridge deck and abutment cost estimates, including P&G and margins.

Renewal/Operating costs: Key differential being area of structure and differing surface

treatments. It is recognised that all options will require a similar, minimum amount of

operating expenditure and a figure of 1.5% of the capital cost estimate was calculated to

give an approximate annual maintenance and renewal cost for each option.

Safety

Traffic safety: Assessed by workshop and reviewed by Road Safety Auditor considering effectiveness of traffic calming, visibility and sight lines and the safe interaction of pedestrians, cyclists and vehicles using each option.

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CPTED: Assessed by workshop against Crime Prevention Through Environmental Design (CPTED) principles.

Environmental

Each assessed by workshop.

Stormwater: Key differential being the impervious surface of each option.

Landscape/Visual: The visual impact, size of the structure and any mitigations to reduce the landscape effects of the bridge.

Ecology: Impact on surrounding ecology, key differential is the size of the structure and area of Newmarket Park land affected.

Earthworks: Volume of earthworks required for each option.

Urban Design: Assessed against urban design principles.

Noise: Key differential being road surface treatment, e.g. speed tables or textured surface.

Cultural

Maori values analysis: Assessed by internal workshop between AT Planning, Project Manager, and AT Maori Policy and Engagement. Criteria includes effects on sites and places of value/significant, effects on waterways, effects on cultural landscapes and effects on customary rights.

Heritage: Assessed by workshop, identifying and evaluating the level of effect on any areas of historic or heritage value.

Social

Level of service: Assessed by workshop. Includes the quality of the connection for users, including adequate road widths, acceptable gradients, suitability for service and emergency vehicles and minimising of vehicle queuing.

Wider community impact: Derived from feedback gathered from the Waitemata Local Board, community groups and feedback from residents or landowners not located in directly-affected streets.

Construction impact: Assessed by workshop. The impact of the option’s construction on traffic flows and affected stakeholders.

Resident feedback: Derived from results of survey, represents feedback from residents or landowners in directly-affected streets of Sarawia Street, Cowie Street, Laxon Terrace and Youngs Lane.

Criteria for each option have been equally ranked in comparison to the other options shortlisted for

consideration as a baseline, with the sensitivity analysis altering weightings to test the options

analysis under different assumptions and priorities.

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How each option supports the project objectives was assessed and applied to each criterion on a 0

to 5 scale as follows:

0 Unacceptable

1 Poor

2 Mediocre

3 Neutral

4 Good

5 Excellent

Sensitivities applied consist of:

Expert Assessed: during the internal workshop, attendees weighted each category to reflect

the priorities of the project objectives.

Economic: Economic criteria weighted at 75% collectively, with remaining criteria

collectively adding to 25%.

Safety: Safety criteria weighted at 75% collectively, with remaining criteria collectively

adding to 25%.

Environmental: Environmental criteria weighted at 75% collectively, with remaining criteria

collectively adding to 25%

Cultural: Cultural criteria weighted at 75% collectively, with remaining criteria collectively

adding to 25%

Social: Social criteria weighted at 75% collectively, with remaining criteria collectively adding

to 25%

Monte Carlo simulation: Probability-based simulation conducted to assess the sensitivity of

the MCA outcome to variations in weightings. This was achieved by carrying out ten

thousand tests in which random weightings were assigned to each criterion. A Monte Carlo

simulation was not performed for the observation platform analysis.

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Results Summary

The overall results are displayed in Figure 4 below:

Figure 4: Results Summary (3 Options Assessed)

Option 1 - Shared

Path

Option 2 - Pedestrian Footpath

Option 3 - Combined

Space

Observation Platform -

Yes Observation

Platform - No

Base Case 44 44 50 53 49

Expert Assessed Sensitivity 2.93 2.73 2.85 3.27 3.05

Economic Weighted Sensitivity 2.61 2.93 3.32 2.70 3.01

Safety Weighted Sensitivity 3.30 2.93 1.94 3.39 3.01

Environmental Weighted Sensitivity 2.50 2.94 3.33 3.52 3.02

Cultural Weighted Sensitivity 2.95 2.93 2.98 3.05 3.01

Social Weighted Sensitivity 2.95 2.24 3.15 3.22 3.18

Monte Carlo Sensitivity 2.75 2.75 3.13 N/A N/A

OVERALL Not

Preferred Not Preferred Safety Not Acceptable Preferred Not Preferred

Ranking: 1st

Yes

2nd

No

3rd

Option 3 is the preferred option in every scenario excluding the Expert Assessed and Safety

Weighted sensitivities. However, following comments emerging from the workshop and subsequent

discussion with AT Road Safety and the Road Safety Auditor, it was apparent that the combination of

a combined space for vehicles, pedestrians and cyclists with the narrow bridge width proved a

challenging combination to implement safely, even with the addition of the buffers spaced along the

length of the road. Accordingly, the Traffic Safety criterion was adjusted to score 0, an Unacceptable

score.

The concern is principally that vehicles pulling to one side behind a buffer to allow another

oncoming vehicle to pass will be inclined to steer into the area prioritised for pedestrians, potentially

blocking a pedestrian’s route of travel or pinning a pedestrian up against the handrail.

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Widening the carriageway would mitigate this risk, but results in a bridge width equivalent to Option

2, at which point many of the benefits allocated to Option 3 are equally shared by Option 2, being

associated with the lowest cost and lowest impact on Newmarket Park land area.

At this point, a new option seeking to combine the traffic calming benefits of Option 3 with the

separated footpath and wider footprint of Option 2 was prepared:

Option 4: Optimised Mix of Options 2 and 3

The option includes a two-lane carriageway, each lane 2.5m wide, with a 1.8m wide footpath

running along one side of the bridge. The carriageway includes a pedestrian refuge in Cowie Street

and narrowing of the carriageway at the Cowie Street end to assist with traffic calming. Textured

surface at the curve of the road further assists with traffic calming and a chicane near the Laxon

Terrace end of the carriageway is combined with a rain garden and rest area.

This option gives a separated pedestrian area and wider bridge footprint to address traffic safety

concerns of Option 3 while retaining some narrowing at either end of the construction to provide

traffic calming.

Figure 5: Optimised Mix of Options 2 and 3

The inclusion of an observation platform at the curve of the bridge was favoured by the assessment

in all criteria excluding the Economic Weighted sensitivity, due to its comparatively higher cost. The

cost of the addition is comparatively small, at 0.7% of the averaged total bridge construction costs,

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and the assessment concludes that on balance, the observation platform should be included in the

final design.

The new option was discussed with AT workshop attendees, the Waitemata Local Board and the AT

Maori Policy and Engagement team and a revised MCA analysis was undertaken, including the new

Option 4.

Figure 6: Results Summary (4 Options Assessed)

Option 1 - Shared

Path


Option 3 - Combined

Space

Option 4 – Mix of Opt 2

and 3

Observ. Platform

- Yes

Observ. Platform

- No

Base Case 44 44 50 49 53 49

Expert Assessed Sensitivity 2.93 2.73 2.85 3.06 3.27 3.05

Economic Weighted Sensitivity 2.61 2.93 3.32 3.00 2.70 3.01

Safety Weighted Sensitivity 3.30 2.93 1.94 3.00 3.39 3.01

Environmental Weighted Sensitivity 2.50 2.94 3.33 3.12 3.52 3.02

Cultural Weighted Sensitivity 2.95 2.93 2.98 3.00 3.05 3.01

Social Weighted Sensitivity 2.95 2.24 3.15 3.00 3.22 3.18

Monte Carlo Sensitivity 2.75 2.75 3.12 3.06 N/A N/A

OVERALL Not

Preferred Not Preferred Safety Not Acceptable Preferred Preferred

Not Preferred

Ranking: 1st

Yes

2nd

No

3rd

4th

The revised MCA assessment continues to rank Option 3 highly, retaining 1st position in all but the

Expert Assessed, Safety Weighted and Cultural Weighted sensitivities. However, Option 4 presents

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the best overall balance, scoring 1st or 2nd ranking in all scenarios, and successfully mitigates the

traffic safety concerns of Option 3.

The inclusion of an observation platform remains recommended.

Further detail on the assessment and sensitivities is provided below:

Base Assessment

Figure 7: Base Assessment with equal weighting across criteria

Option 1 - Shared

Path


Option 3 - Combined

Space

Option 4 – Mix of Opt

2 and 3

Observ. Platform -

Yes

Observ. Platform

- No

Economic*

Capital Cost 2 3 4 3 2 3

Operating Cost 3 3 3 3 3 3

Safety

Traffic Safety 4 3 0 3 3 3

CPTED 3 3 3 3 4 3

Environmental

Stormwater 2 3 3 3 3 3

Landscape/Visual 2 3 4 3 5 3

Ecology 2 3 4 3 3 3

Earthworks 2 3 4 3 3 3

Urban Design 3 3 4 4 5 3

Noise 3 3 2 3 3 3

Cultural

Maori Values** 3 3 3 3 3 3

Heritage 3 3 3 3 3 3

Social

Level of Service 4 2 3 3 4 3

Wider Community† 3 1 4 3 4 3

Constr. Impact 3 3 3 3 2 3

Resident Feedback† 2 2 3 3 3 4

Total 44 44 50 49 53 49

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Ranking: 1st

Yes

2nd

No

3rd

4th

*Economic scores are calculated as follows:

Capital cost estimate: Costs are averaged and average cost assigned a score of 3. Every 1%

difference in cost from the average adds or subtracts 0.2 to the option’s score. To calculate

the observation platform score the zero cost option was scored at 3 and the additional cost

for including the platform reducing the score by 0.1 for every additional 0.1% of construction

cost. Results were rounded to the nearest whole number.

Renewal/Operating cost estimate: Costs are averaged and average cost assigned a score of

3. Every 1% difference in cost from the average adds or subtracts 0.1 to the option’s score.

This differential is lower than that for capital cost to reflect that the actual difference in

operating costs between options will be minor due to minimal costs to maintain the

structure at all.

**Maori values analysis was calculated by scoring the following sub-criteria and averaging the

results for an overall score:

Figure 8: Maori Values Analysis Sub-Criteria scores by option

Maori Values Analysis

Option 1 - Shared

Path


Option 3 - Combined

Space

Option 4 – Mix of

Opt 2 and 3

Observ. Platform

- Yes

Observ. Platform

- No

Effects on Sites/ Places of Value/Significance 4 4 5 4 5 2

Effects on Waterways 1 2 3 2 2 3

Effects on Cultural Landscapes 2 2 2 2 3 3

Customary Rights 3 3 3 3 3 3

AVERAGE 2.5 2.75 3.25 2.75 3.25 2.75

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Sub-criteria are measured by:

Figure 9: Maori Values Analysis Sub-Criteria Measures

Sub-Criteria Measures

Effects on Sites/ Places of Value/Significance Mauri; Waahi Tapu; Historical; Customary needs; Contemporary esteem

Effects on Waterways Mauri; Waahi Tapu; Historical; Customary needs; Contemporary esteem

Effects on Cultural Landscapes Mauri; Waahi Tapu; Historical; Customary needs; Contemporary esteem

Customary Rights Extent of effects on areas of protected customary rights (under Takutai Moana or Treaty Redress)

†Resident feedback is derived from results from Newmarket Level Crossing: Survey Results, January

2015, which collates responses received back from residents, landowners and community groups to

a survey distributed by AT. Only results from residents or landowners associated with properties in

Sarawia Street, Laxon Terrace, Youngs Lane and Cowie Street are included under Resident Feedback,

the other responses are reflected under the Wider Community Impact score.

Sensitivity Assessments

The sensitivities applied to the multi-criteria analysis are:

Expert Assessed Weightings

The February 2015 workshop attendees assessed each criterion and applied variable weightings to

reflect relative importance to achieving the project objectives.

The weightings were assessed to best reflect the priorities of the project objectives.

Figure 10: Expert-assessed Weightings

Category Criteria Weighting Sub-Weighting

Economic 24%

Capital Cost 17%

Operating Cost 07%

Safety 22%

Traffic Safety 17%

CPTED 05%

Environmental 22%

Stormwater 04%

Landscape/Visual 06%

Ecology 02%

Earthworks 02%

Urban Design 06%

Noise 02%

Cultural 08%

Maori Values Analysis 06%

Heritage 02%

Social 24%

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Level of Service 12%

Wider Community Impact 05%

Construction Impact 02%

Resident Feedback 05%

Figure 11: Sensitivity Assessment with Expert Weightings

Option 1 - Shared

Path


Option 3 - Combined

Space


2 and 3

Observ. Platform -

Yes

Observ. Platform

- No

Economic

Capital Cost 0.34 0.51 0.68 0.51 0.34 0.51

Operating Cost 0.21 0.21 0.21 0.21 0.21 0.21

Safety

Traffic Safety 0.68 0.51 0.00 0.51 0.51 0.51

CPTED 0.15 0.15 0.15 0.15 0.20 0.15

Environmental

Stormwater 0.08 0.12 0.12 0.12 0.12 0.12

Landscape/Visual 0.12 0.18 0.24 0.18 0.30 0.18

Ecology 0.04 0.06 0.08 0.06 0.06 0.06

Earthworks 0.04 0.06 0.08 0.06 0.06 0.06

Urban Design 0.18 0.18 0.24 0.24 0.30 0.18

Noise 0.06 0.06 0.04 0.06 0.06 0.06

Cultural

Maori Values 0.18 0.18 0.18 0.18 0.18 0.18

Heritage 0.06 0.06 0.06 0.06 0.06 0.06

Social

Level of Service 0.48 0.24 0.36 0.36 0.48 0.36

Wider Community 0.15 0.05 0.20 0.15 0.20 0.15

Constr. Impact 0.06 0.06 0.06 0.06 0.04 0.06

Resident Feedback 0.10 0.10 0.15 0.15 0.15 0.20

Total 2.93 2.73 2.85 3.06 3.27 3.05

Ranking: 1st

Yes

2nd

No

3rd

4th

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Specified Category Weightings

Each sensitivity assigns 75% weighting to each high-level category (Economic, Safety, etc.) divided

equally across all criteria within this category. The remaining 25% is evenly divided across the

remaining criteria.

These sensitivities test the options analysis against a prioritisation of each category in turn to

establish if there are weak areas or inconsistencies in specific areas not revealed by the base

analysis.

Figure 12: Sensitivity Assessment prioritising Economic Outcomes

Option 1 - Shared

Path


Option 3 - Combined

Space


2 and 3

Observ. Platform -

Yes

Observ. Platform

- No

Economic

Capital Cost 0.75 1.13 1.50 1.13 0.75 1.13

Operating Cost 1.13 1.13 1.13 1.13 1.13 1.13

Safety

Traffic Safety 0.13 0.09 0.00 0.09 0.09 0.09

CPTED 0.09 0.09 0.09 0.09 0.13 0.09

Environmental

Stormwater 0.02 0.03 0.03 0.03 0.03 0.03


Ecology 0.02 0.03 0.04 0.03 0.03 0.03

Earthworks 0.02 0.03 0.04 0.03 0.03 0.03

Urban Design 0.03 0.03 0.04 0.04 0.05 0.03

Noise 0.03 0.03 0.02 0.03 0.03 0.03

Cultural

Maori Values 0.09 0.09 0.09 0.09 0.09 0.09

Heritage 0.09 0.09 0.09 0.09 0.09 0.09

Social

Level of Service 0.06 0.03 0.05 0.05 0.06 0.05

Wider Community 0.05 0.02 0.06 0.05 0.06 0.05

Constr. Impact 0.05 0.05 0.05 0.05 0.03 0.05


Total 2.61 2.93 3.32 3.00 2.70 3.01

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Ranking: 1st

Yes

2nd

No

3rd

4th

Figure 13: Sensitivity Assessment prioritising Safety Outcomes

Option 1 - Shared

Path


Option 3 - Combined

Space


2 and 3

Observ. Platform -

Yes

Observ. Platform

- No

Economic

Capital Cost 0.06 0.09 0.13 0.09 0.06 0.09

Operating Cost 0.09 0.09 0.09 0.09 0.09 0.09

Safety

Traffic Safety 1.50 1.13 0.00 1.13 1.13 1.13

CPTED 1.13 1.13 1.13 1.13 1.50 1.13

Environmental

Stormwater 0.02 0.03 0.03 0.03 0.03 0.03


Ecology 0.02 0.03 0.04 0.03 0.03 0.03

Earthworks 0.02 0.03 0.04 0.03 0.03 0.03

Urban Design 0.03 0.03 0.04 0.04 0.05 0.03

Noise 0.03 0.03 0.02 0.03 0.03 0.03

Cultural

Maori Values 0.09 0.09 0.09 0.09 0.09 0.09

Heritage 0.09 0.09 0.09 0.09 0.09 0.09

Social

Level of Service 0.06 0.03 0.05 0.05 0.06 0.05

Wider Community 0.05 0.02 0.06 0.05 0.06 0.05

Constr. Impact 0.05 0.05 0.05 0.05 0.03 0.05


Total 3.30 2.93 1.94 3.00 3.39 3.01

Ranking: 1st

Yes

2nd

No

3rd

4th

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Figure 14: Sensitivity Assessment prioritising Environmental Outcomes

Option 1 - Shared

Path


Option 3 - Combined

Space


2 and 3

Observ. Platform -

Yes

Observ. Platform

- No

Economic

Capital Cost 0.06 0.09 0.13 0.09 0.06 0.09

Operating Cost 0.09 0.09 0.09 0.09 0.09 0.09

Safety

Traffic Safety 0.13 0.09 0.00 0.09 0.09 0.09

CPTED 0.09 0.09 0.09 0.09 0.13 0.09

Environmental

Stormwater 0.25 0.38 0.38 0.38 0.38 0.38


Ecology 0.25 0.38 0.50 0.38 0.38 0.38

Earthworks 0.25 0.38 0.50 0.38 0.38 0.38

Urban Design 0.38 0.38 0.50 0.50 0.63 0.38

Noise 0.38 0.38 0.25 0.38 0.38 0.38

Cultural

Maori Values 0.09 0.09 0.09 0.09 0.09 0.09

Heritage 0.09 0.09 0.09 0.09 0.09 0.09

Social

Level of Service 0.06 0.03 0.05 0.05 0.06 0.05

Wider Community 0.05 0.02 0.06 0.05 0.06 0.05

Constr. Impact 0.05 0.05 0.05 0.05 0.03 0.05


Total 2.50 2.94 3.33 3.12 3.52 3.02

Ranking: 1st

Yes

2nd

No

3rd

4th

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Figure 15: Sensitivity Assessment prioritising Cultural Outcomes

Option 1 - Shared

Path


Option 3 - Combined

Space


2 and 3

Observ. Platform -

Yes

Observ. Platform

- No

Economic

Capital Cost 0.06 0.09 0.13 0.09 0.06 0.09

Operating Cost 0.09 0.09 0.09 0.09 0.09 0.09

Safety

Traffic Safety 0.13 0.09 0.00 0.09 0.09 0.09

CPTED 0.09 0.09 0.09 0.09 0.13 0.09

Environmental

Stormwater 0.02 0.03 0.03 0.03 0.03 0.03


Ecology 0.02 0.03 0.04 0.03 0.03 0.03

Earthworks 0.02 0.03 0.04 0.03 0.03 0.03

Urban Design 0.03 0.03 0.04 0.04 0.05 0.03

Noise 0.03 0.03 0.02 0.03 0.03 0.03

Cultural

Maori Values 1.13 1.13 1.13 1.13 1.13 1.13

Heritage 1.13 1.13 1.13 1.13 1.13 1.13

Social

Level of Service 0.06 0.03 0.05 0.05 0.06 0.05

Wider Community 0.05 0.02 0.06 0.05 0.06 0.05

Const. Impact 0.05 0.05 0.05 0.05 0.03 0.05


Total 2.95 2.93 2.98 3.00 3.05 3.01

Ranking: 1st

Yes

2nd

No

3rd

4th

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Figure 16: Sensitivity Assessment prioritising Social Outcomes

Option 1 - Shared

Path


Option 3 - Combined

Space


2 and 3

Observ. Platform -

Yes

Observ. Platform

- No

Economic

Capital Cost 0.06 0.09 0.13 0.09 0.06 0.09

Operating Cost 0.09 0.09 0.09 0.09 0.09 0.09

Safety

Traffic Safety 0.13 0.09 0.00 0.09 0.09 0.09

CPTED 0.09 0.09 0.09 0.09 0.13 0.09

Environmental

Stormwater 0.02 0.03 0.03 0.03 0.03 0.03


Ecology 0.02 0.03 0.04 0.03 0.03 0.03

Earthworks 0.02 0.03 0.04 0.03 0.03 0.03

Urban Design 0.03 0.03 0.04 0.04 0.05 0.03

Noise 0.03 0.03 0.02 0.03 0.03 0.03

Cultural

Maori Values 0.09 0.09 0.09 0.09 0.09 0.09

Heritage 0.09 0.09 0.09 0.09 0.09 0.09

Social

Level of Service 0.75 0.38 0.56 0.56 0.75 0.56

Wider Community 0.56 0.19 0.75 0.56 0.75 0.56

Constr. Impact 0.56 0.56 0.56 0.56 0.38 0.56


Total 2.95 2.24 3.15 3.00 3.22 3.18

Ranking: 1st

Yes

2nd

No

3rd

4th

Monte Carlo Simulation

A Monte Carlo simulation was conducted to assess the sensitivity of the MCA outcome to variations

in weightings. This was achieved by carrying out ten thousand tests in which random weightings

were assigned to each criterion. The average rank and average weighted score of the four bridge

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options across the 10,000 simulations is shown in figure 17, while the ranking occurrence for each

option over the 10,000 simulations is shown in figure 18.

This sensitivity was not performed for the observation platform.

Figure 17: Sensitivity Assessment with Monte Carlo analysis

Average Rank

Average Score

Option 1 3.48

Option 1 2.75

Option 2 3.49

Option 2 2.75

Option 3 1.34

Option 3 3.13

Option 4 1.69

Option 4 3.06

Figure 18: Ranking Occurrences over 10,000 Monte Carlo Simulations

Rank Option 1 Option 2 Option 3 Option 4

1 0.0% 0.0% 68.7% 30.9%

2 2.0% 0.2% 28.6% 68.7%

3 47.6% 50.1% 2.0% 0.0%

4 50.0% 49.3% 0.3% 0.0%

Ranking: 1st

2nd

3rd

4th

25


Conclusion

The results indicate Option 3 as the highest-scoring option in most criteria, but Option 4 presents the

best overall position, ranking 1st or 2nd in every criterion. Option 3 has fundamental challenges

meeting the traffic safety criterion and achieved an unacceptable score in this area.

The principal differentiators in the assessment are found in some criteria more than others. Key

differentiating criteria emerging from the assessment are:

Capital Cost Estimate: principally, the wider the structure, the higher the cost.

Traffic Safety: mostly affects the more novel Option 3, but also reflected in the higher-

scoring Option 1 which includes a shared cycle and pedestrian path separated from the

vehicle carriageway.

Environmental Criteria: principally Landscape/Visual, Ecology and Earthworks where the

wider structures have a greater impact visually and on nearby Newmarket Park. This is an

important factor in why Option 3 consistently scores highly in the MCA.

Level of Service: greater amenity provided by the wider bridge footprints is reflected in this

score.

Wider Community Impact: opinion tended to be polarised in this criterion, with little

support for Option 2 and a division between the higher cycle amenity levels of Option 1

versus the lower cost, lower impact on Newmarket Park of Option 3. Option 4 picked up

some of the support for Option 3, following the traffic safety issues, as the next best option

in this respect, balancing width with traffic safety with traffic calming measures.

Resident Feedback: The scores are not widely varied, but the criterion warrants further

discussion as the survey results were polarised between options. The averaged survey

results led to scores of 2 or 3 as the feedback in favour and opposed to each option,

particularly Options 1 and 3, tended to cancel one another out. There was no single clear

preferred option emerging from the feedback, and the similar scores reflect this. The results

of the survey are described in greater detail in Appendix 2.

The other criteria tended to score similarly as the differences in impact between options were

usually minor. For example, heritage impact for each option are identical as the heritage impacts for

any bridge in this location are the same or very similar.

The observation platform assessment indicates that this should be included in the final design. The

comparatively minor cost to include it (0.65% of the construction capital cost estimate for Option 4)

and potential lost opportunity if this is not included in the structure now and considered desirable

later due to growth in pedestrian and cycle use of the bridge also support inclusion of the

observation platform in the design.

Based on the MCA outlined in this report, bridge concept Option 4 with an observation platform

included is selected as the preferred option to progress to detailed design. This option consists of

two traffic lanes of 2.5m width each with a 1.8m footpath on one side of the carriageway.

26


Appendices

Appendix 1: MCA Workshop Minutes, 3rd February 2015

Appendix 2: Newmarket Level Crossing Project – Survey Results, January 2015

27


Appendix 1: MCA Workshop Minutes

MINUTES OF MEETING

File: Newmarket Level

Crossing

Sheet: Concept Options

MCA Workshop Date: 03/02/2015 Time: 10AM - 2PM

Subject Concept Options MCA Workshop – minutes

Location Meeting room 1, Opus International

Consultants, The Westhaven, Auckland, NZ

Minutes By: Moustafa Al-Ani

Persons Present Organisation

1. Moustafa Al-Ani (MA) Opus

2. Shane Dale (SD) Auckland Transport

3. Andy Irwin (AI) Auckland Transport

4. Michael Perry (MP) Auckland Transport

5. Nesh Pillay (NP) Auckland Transport

6. Adrian Price (AP) Auckland Transport

7. Sarah Rowan (SR) Opus

8. Jarrod Snowsill (JS) Opus

9. Ina Stenzel (IS) Auckland Transport

10. Peter Wiles (PW) Opus

Item Discussion and Action Actions

0 Apologies: Simon Lough, Nick Seymour, Irene Tse

28



1

Purpose of Workshop

MA detailed the purpose of the workshop – to evaluate the 3 concept design

options for the purposes of a Multi-Criteria Analysis (MCA) for 9 criteria. The

aim of the MCA is to facilitate a decision for the preferred concept design

option.

AP clarified that a similar process is also to be undertaken for the observation

platform.

Both

2

Project Background

AP presented a brief background of the project. ALL in attendance indicated at

least a moderate level of knowledge of the project background.

3

Scoring of Criteria

The scoring process involved a fluid discussion of the advantages and

disadvantages of each option by ALL in attendance, with scores allocated as

follows:

1. Poor

2. Mediocre

3. Neutral

4. Good

5. Excellent

The main points of discussion were recorded and have been captured below.

3.1

Traffic Safety:

Options 1&2:

o road could be narrowed earlier (closer to Cowie St end)

o ~300mm wide kerb before barriers

o could also include buffers, as per option 3

Option 3:

o Distance between buffers could be shortened (to 10m?)

o Different (rougher) pavement texture should be used along the

footpath side for the visually-impaired

o Preference would be for no lowered speed limit at this stage but

to revisit this issue at a later date if required.

Option 1 2 3

Score 4 3 2

29



3.2

Crime Prevention through Environmental Design (CPTED):

The differences between the three options are not expected significantly affect

the CPTED outcomes of the design.

Option 1 2 3

Score 3 3 3

3.3

Stormwater:

Option 3 has the lowest impervious surface of the three options,

followed by option 2, with option 1 introducing the largest impervious

area.

Option 3 has the largest potential for stormwater treatment due to the

reduced impact on Newmarket Park land allowing for greater areas of

treatment swales.

If possible, stormwater from Cowie St catchment is to be collected and

treated along with the stormwater from the new impervious surface.

This will require separation of the existing combined sewer at the

bottom of Cowie St.

Option 3 increased treatment potential is dependent on the ability of

the reduced carriageway width to carry stormwater from the Cowie St

catchment. If this is confirmed, the score for option 3 should be

increased to a 4.

Option 1 2 3

Score 2 3 3*

3.4

Landscape/Visual:

Planting on rail side unlikely for all options

Patterning on walls and abutments will be used to enhance the overall

aesthetic appeal of the project

Planted trees will likely need 10-15 years to re-grow to existing

age/height

Ayr St residents are keen to retain view of Newmarket Park, not bridge.

Option 1 2 3

Score 2 3 4

30



3.5

Ecology:

Ecological impact influenced by footprint. Largest footprint is for option

1, followed by option 2, with option 3 having the smallest footprint.

Stormwater treatment swales also support life, and therefore the option

allowing the largest area of swales (option 3) provides the most

ecological mitigation.

Option 1 2 3

Score 2 3 4

3.6

Earthworks:

The option with the smallest footprint (option 3) has the smallest impact

in terms of earthworks.

Option 1 2 3

Score 2 3 4

3.7

Urban Design:

Option 3 provides more opportunities for incorporation of urban design

elements, including into the buffers.

Option 1 2 3

Score 3 3 4

3.8

Heritage:

The differences between the three options are not expected significantly affect

the heritage impact of the design.

Option 1 2 3

Score 3 3 3

31



3.9

Level of Service:

The access and level of service provided to pedestrians and cyclists is

prioritised over that provided to vehicular traffic.

Option 2, designed to match the existing widths at Laxon Terrace and

provide minimal impact on Park land for a separated roadway option,

falls below AT Codes of Practice and is considered the weakest option

due to inadequate footpath width and the shifting of cyclists onto the

road.

While the 3m combined path in option 1 meets minimum standards,

current thought is that pedestrians prefer to not share space.

Option 3 doesn’t provide defined space for cyclists.

Option 1 2 3

Score 4 2 3

4

Observation Platform

Local resident feedback is generally split but roughly estimated to be

60% against to 40% in favour of the observation platform

Mana Whenua feedback has been strongly in favour of the platform

CPTED:

o The observation platform introduces additional passive

surveillance

o The platform will need to be well-lit, and not concealed

o The platform is expected to encourage positive use of the route.

Criteria Observation platform - Yes

Observation platform - No

Traffic Safety 3 3 CPTED 4 3 Stormwater 3 3 Landscape/Visual

5 3

Ecology 3 3 Earthworks 3 3 Urban Design 5 3 Heritage 3 3 Level of Service

4 3

32



5

Expert Weightings

ALL in attendance were asked for input into the relative weightings of the

criteria to be used for the MCA.

The following comments were noted during this process:

The weighting for cost can be increased in this case as the difference

between the three options for the remaining criteria is generally not

prominent.

Traffic safety and level of service remain prominent as they directly

address the project objectives.

Where the differences between the three options are notably minor,

such as for noise or earthworks, relatively small weighting has been

attached to these criteria.

Criteria Weighting

Economic 24%

Capital Cost Estimate 17%

Renewal/Operating Cost Estimate 7%

Safety 22%

Traffic Safety 17%

CPTED 5%

Environmental 22%

Stormwater 4%

Landscape/Visual 6%

Ecology 2%

Earthworks 2%

Urban Design 6%

Noise 2%

Cultural 8%

Mana Whenua Impact 6%

Heritage 2%

33



6

Other Comments and Wrap-up

General comments:

Fencing will be required at KiwiRail accessway

Additional signage will be required on Cowie St for all options

Signage and traffic calming will be required at the Cowie St-Parnell Rd

intersection

The location of turning heads, if any, needs to be addressed

No parking or stopping is to be allowed along the bridge for all options

Colour and/or texture of pavement surface can be used to differentiate

between vehicle and pedestrian regions for option 3

The use of rough-textured pavement surface could lead to noise issues

Wrap-up:

The scores arrived at from the workshop will be combined with scores for other

criteria to determine the preferred concept option and the preferred

observation platform option. The timeline for this decision is anticipated to be

by the end of the week (6th February, 2015).

AP, MA, NP,

JS

34


Appendix 2: Newmarket Level Crossing Project – Survey Results

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