Assessing The Underworld

An Integrated Performance Model of City Infrastructures

Thinking Differently

A Sustainability Assessment Framework for

Streetworks

Aryan Hojjati, Ian Jefferson, Nicole Metje, Chris Rogers

University of Birmingham

21st November 2017

Sustainability Assessment Framework

The Aim – “to develop a sustainability assessment framework forstreetworks, which establishes the true total cost (economic, socialand environmental) and ‘value’ of interventions, and thus buttressthe outputs from the ATU DSS to inform decision making and henceensure more sustainable and intelligent streetworks”.

…. by collecting detailed information that enables acomprehensive sustainability assessment of the project.

Utility Streetworks and Associated Costs

Issue Impact

~ £7 billion per annum: cost of utility streetworks to the UK economy

78% of which is indirect costs including social and environmental impacts

Road occupation due to utility streetworks causing traffic delays

Accounted for equivalent of ~ 6.16 million days of work in the UK in 2014-2015

An estimated 1.37 million streetworksundertaken by utility companies alone

This equates to 2.4 million road openings in the UK in 2014-2015

• In 2014-2015 alone, utility streetworks in England and Wales have incurred costs of more than £1.5bn.

• The projected cumulative total cost of utility streetworks in the UK from 2013 to 2030 is £319bn.

Sustainability

Reference: http://www.commons.wikimedia.org

Productivity

Environmental ImpactExample: Damages to tree roots (from utilities) and vice versa

Utility Streetworks and Associated Costs

Social ImpactExamples: Loss of utility provision, traffic delays, losses to local

businesses, reduced quality of open space

Utility Streetworks and Associated Costs

Review of Sustainability assessment tools

Halcrow Group Limited, 2008

Beronold, 2003

Hayes, 2012

Arup, 2016

The Framework

Streetworks Sustainability Assessment Framework (SSAF)

Conceptualisation:

• Pre-Appraisal tool: SPeAR® was adapted as SSAF-SPeAR to assess sustainability in utility streetworks projects

… based on the three pillars of sustainability with an additional focus on indirect economic costs.

• Integrating qualitative and quantitative assessment approaches by developing a Multi-Criteria Decision Analysis (MCDA) model.

Testing and validation of the SSAF and Sustainability Assessment Model on a number of real case studies both in the UK and the Netherlands.

The case studies include:

• Pipe-Jacking for sewer replacement in Belgium

• Pipe Subways in London

• Multi-Utility Tunnels in Amsterdam

4 Sets of Indicators (Direct Economic, Indirect Economic, Social, Environmental)

Headline Indicator Indicator Category

Construction Direct Economic Impact

Planning and DesignLabour and machineryConstruction materials

Construction worksTraffic management

Maintenance Direct Economic Impact

Planned maintenanceMonitoring

AccessEmergency repairsDecommissioning

Construction Indirect Economic Impact

Third Party utility damageCompensation to businesses for loss of profit

Compensation to customers for interruptions to services

Loss of income to asset owners or utilitiesCompensation to local authorities for damage to

their assets

Maintenance Indirect Economic Impact

GoodwillRequired Training (upskill)

InsuranceLoss of business to competitors

Lost Opportunity Cost

Criteria

Headline Indicator Indicator Category

Construction Social Impact

Delay costs to road users

Disruption to businesses

Disruption to local community

Health and Safety (nuisance)

Costs to local authorities

Maintenance Social Impact

Delay costs to road users

Disruption to businesses

Disruption to local community

Health and Safety (nuisance)

Costs to local authorities

Construction Environmental Impact

Energy efficiency

Materials and waste production

Carbon footprint

Water consumption and pollution

Biodiversity (flora and fauna)

Maintenance Environmental Impact

Energy efficiency

Materials and waste production

Carbon footprint

Water consumption and pollution

Biodiversity (flora and fauna)

Criteria

Results from Questionnaire

Industrial Experts Engagement:- Questionnaire- Interviews- Expert Panel Sessions

Questionnaire – to validate thedeveloped indicator sets and to captureexpert opinion on their importance andapplicability – distributed to a wide groupof industry experts.

… results of the questionnaire, and aseries of interviews and experts panelsessions informed the SustainabilityAssessment Framework for UrbanUtility Streetworks.

Example question in the questionnaire – With regard to utility streetworksprojects, specify the importance of the following headline cost / impact categories,where 1 is the most important and 4 is the least important.

Results from Questionnaire

Trenching – a sustainable solution?

The Challenge…

Open-cut remains the most widely adopted

solution for utility placement by practitioners

and yet various alternative solutions exist,

such as Trenchless Technologies (TT) and

Multi-Utility Tunnels (MUTs).

Possible Solution: Multi-Utility Tunnel (MUT)

Ground source heat

pump

Stored heat

District heating

District cooling

(Borehole abstraction)

HV/LV Electricity

Communications

Gas

Ventilation

Public roads

Public transport

Waste Collection

Stored water

Harvested and abstracted

water

Waste water

Clean water

Jefferson et al., 2006 Hunt et al., 2014

Application of the Pre-Appraisal part of the SSAF (with new sets of criteria) – Case Study Demonstration – Construction stage

Open-cut Trenching vs. Pipe Jacking, Belgium

Open-cut Trenching Pipe Jacking

Results

Summary

• A methodology was developed to both conceptualise the cost and

impacts across short term and long term

• A new suite of headline indicators and associated performance

criteria, coupled with the assessment method, was developed.

• For the first time a long term, total cost approach can be applied to

any potential streetworks activity.

• The pre-appraisal part of the tool was applied to a case study of a

sewer replacement project in Belgium: open-cut trenching vs pipe-

jacking (trenchless technology).

…. A far better performance was achieved for pipe-jacking

compared to the open-cut trenching (Hojjati et al., 2017).

• Overcoming barriers towards adopting alternative utility placement

options is vital toward achieving more sustainable, resilient and

liveable cities of the future.

Summary

• A methodology was developed to both conceptualise the cost and

impacts across short term and long term

• A new suite of headline indicators and associated performance

criteria, coupled with the assessment method, was developed.

• For the first time a long term, total cost approach can be applied to

any potential streetworks activity.

• The pre-appraisal part of the tool was applied to a case study of a

sewer replacement project in Belgium: open-cut trenching vs pipe-

jacking (trenchless technology).

…. A far better performance was achieved for pipe-jacking

compared to the open-cut trenching (Hojjati et al., 2017).

• Overcoming barriers towards adopting alternative utility placement

options is vital toward achieving more sustainable, resilient and

liveable cities of the future.

Considering short-term and long-term impact!

Demonstration of sustainable credentials of alternative

solutions

Sustainability Evaluation Method bespoke to utility streetworks

developed

Thank You