Download - Dr Joel Byrnes | Associate Director, AECOM

Intelligent Water Networks – is science the key to driving productivity and efficiency in urban water?

Dr Joel Byrnes| Associate Director, AECOM

November 2012

Intelligent Water Networks – Background•Intelligent Water Networks (IWN) Consortium of Victorian Water

Authorities, working with state government

•Industry Driver: The increasing costs and consequences associated with operating water, wastewater drainage networks

•Traditional approaches to monitoring condition and deterioration are invasive and costly....

•....But, monitoring technology advances have occurred in other sectors that are now relevant to water/wastewater/drainage networks

Intelligent Water Networks – Background

Task: Identify, review and prioritise monitoring technologies for enhanced asset management of

water/wastewater/drainage networks

Mapping technologies to asset types and performance indicators

•Water sector avoiding monitoring technologies that simply provide scientific innovation

Technologies providing business benefits merit further development

•Identified technologies must be matched to key assets and performance indicators

•Satisfy assessment criteria that clearly demonstrate the value of implementing technology

•Demonstrate economic efficiency in technology investment


Use “Failure pathways” to identify system parameters that can be monitored for each asset type

EVENTBURST MAIN

(ALL)Fracture/blown section

Perforation (i.e. localised corrosion

pitting, ductile rupture

(ALL)Surge pressure/cyclic

pressure

(ALL)Inappropriate pump/valve

operation

EVENTLEAK

(ALL apart from PE)

Joint leak

(ALL)Pipe deformation

(ALL)Pipe bending (broken

back)

(AC, MS(CL), DI (CL), CI (CL))

Internal corrosion

(MSCL, DICL, CICL)

Spalling of internal cement mortar lining

(MSCL, DICL, CICL)

Leaching of internal cement mortar lining

(AC, MSCL, DICL, CICL)

Source water, chemistry change (to soft water)

AC, MS(CL), DI(CL), CI(CL)External corrosion

(MS(CL), DI (CL), CI (CL))

External coating breach

(ALL)Soil movement

(ALL apart from PE)

Soil environment change

(ALL)Climate variables (temp,

rainfall)

(MS(CL))Cathodic protection

failure

Water supply -Burst & LeakMaterials key

AC = asbestos cementCI(CL) = cast iron (cement lined)DI(CL) = ductile iron (cement lined)GRP = glass reinforced plasticMS(CL) = mild steel (cement lined)PE = polyethylenePVC = polyvinyl chlorideRC = reinforced concrete

Rising Mains – Sewage Spill

EVENT SEWAGESPILL

(ALL)Pipe Fracture/Collapse

and/or Blockage


pressure beyond design limit

Inappropriate pump/valve operation

(ALL apart from PE/ PVC)

Corrosion of pipe wall/

Loss of strength


Loss of soil support/voiding


Axial bending of small diameter pipe (i.e. 'broken back')

(ALL apart from PE/PVC)

Internal corrosion

MS (CL)Cathodic protection failure


External corrosion

(MS, DI )External coating

breach


Sewage exfiltration

(ALL apart from PE)

J oint Leak

(ALL)Pipe deformation)

(ALL)Soil Movement

(ALL)Soil environment

change

(ALL)Climate variables (temp, rainfall)

(ALL)Aggressive chemicals

discharged into sewer


Sulphuric acid generation


Air release valve not functioning


Presence of occluded air


Sulphide generation in sewer

(ALL apart from PE)

Tree root penetration

Materials key


Failure pathway diagrams provides constraint for identifying relevant technologies


Tech

ID

Technology Asset type (s) Relevant failure event Primary distress indicator and pathway

A Acoustic instrumentation to monitor head loss/roughness/blockage Gravity Sewer Pipe Blockage (Reduced sewer

conveyance capacity)

Pipe blockage, Local constriction to flow

B Flow velocity monitoring to detect sedimentation Gravity Sewer Pipe Blockage (Reduced sewer

conveyance capacity), Sewage spill

Decreased flow velocities(insufficient for sedimentation

suspension), siltation, blockage, sulphide generation

through to internal corrosion, collapse

C Flow monitoring to detect blockage in gravity sewers (Penine Water

Group, Univ Sheffield)

Gravity Sewer Pipe Blockage (Reduced sewer

conveyance capacity)

Pipe blockage, Local constriction to flow

D Real time monitoring of dissolved Sulphide in sewers Gravity Sewer Sewage spill Sulphide generation, internal corrosion, collapse

E Pressure transients to detect internal deterioration Water Burst main Spalling of cement mortar lining, internal corrosion

through to burst main

E Pressure transients to detect presence of air pockets Sewer rising mains Sewage spill Presence of occluded air, through to sulphuric acid

generation

F Optical fibre monitoring for structural condition (External) Gravity Sewer Sewage spill Soil movement, pipe deformation, Joint Leak

F Optical fibre monitoring for structural condition (External) Sewer rising mains Sewage spill Soil movement, pipe deformation, Joint Leak

F Optical fibre monitoring for structural condition (External) Water Leak, Burst main Soil movement, pipe deformation, Joint Leak

F Optical fibre monitoring for structural condition (Internal) Water Leak, Burst main Surge pressure/cyclic pressure, Joint leak

G Soil temperature/moisture/pressure sensing to infer structural

condition

Gravity Sewer Sewage spill Soil environment change, soil movement, through to

sewage spill


condition

Sewer rising mains Sewage spill Soil environment change, soil movement, through to

sewage spill


condition

Water Leak, Burst main Soil environment change, soil movement, through to leak,

burst main

H In-situ Linear Polarisation Resistance to monitor soil corrosivity Sewer rising mains Sewage spill Soil environment change, external corrosion through to

sewage spill

H In-situ Linear Polarisation Resistance to monitor soil corrosivity Water Leak, Burst main Soil environment change, external corrosion through to

burst main, leak

I Surface based resistivity to monitor soil corrosivity Sewer rising mains Sewage spill Soil environment change, external corrosion through to

sewage spill

I Surface based resistivity to monitor soil corrosivity Water Leak, Burst main Soil environment change, external corrosion through to

burst main, leak


EVENT SEWAGESPILL


and/or Blockage





Corrosion of pipe wall/

Loss of strength




Axial bending of small diameter pipe (i.e. 'broken back')


Internal corrosion



External corrosion

(MS, DI )External coating

breach


Sewage exfiltration

(ALL apart from PE)

J oint Leak


(ALL)Soil Movement


change

(ALL)Climate variables (temp, rainfall)

(ALL)Aggressive chemicals

discharged into sewer









(ALL apart from PE)

Tree root penetration

Materials key



EVENT SEWAGESPILL


and/or Blockage





Corrosion of pipe wall/Loss of strength




Axial bending of small diameter pipe (i.e.

'broken back')


Internal corrosion



External corrosion

(MS, DI)External coating

breach


Sewage exfiltration

(ALL apart from PE)Joint Leak


(ALL)Soil Movement


change

(ALL)Climate variables (temp,

rainfall)

(ALL)Aggressive chemicals discharged into sewer









(ALL apart from PE)Tree root penetration

Tech ID: ETech ID: E

Tech ID: M

Tech ID: N

Tech ID: F, G, H, ITech ID: H, I

Tech ID: F, G

Tech ID: FTech ID: F, G, OTech ID: F, G, O

Tech ID: FTech ID: F

Tech ID: F

L

L

Tech ID: F, G

Materials key


Can ensure that technologies are relevant to actual deterioration processes

• Have identified/matched monitoring technologies to various stages of failure pathway for key assets

• But: Water sector need to assess value proposition in each case and prioritise technologies for further development

• Multi Criteria Assessment to compare technologies against:Potential to save operational response costs and reactive maintenance

costsPotential to save capital through renewal deferralRelative cost/asset coverage lengthFailure pathway coverage & ability for early detectionPotential to reduce social/environmental impacts

Assessment criteria for monitoring technologies

Assessment criteria for monitoring technologies

TECH ID TECHNOLOGY DESCRIPTION

CRITERIA WEIGHTING AND DESCRIPTION

OVERALL SCORE

OVERALL RANKING

4 4 3 2 3 3 3 3 3 2 2

Potential to save opex response

costs

Potential to save

preventative maintenance

costs

Potential to save capital

through renewals or

augmentation deferral

Potential to improve Levels of

Service at the same cost

Relative cost to procure and

install technology

Relative cost to operate

and maintain technology

Relative asset coverage

(length) per monitoring

device

Extent of failure pathway

addressed per monitoring

device

Potential to reduce

disruption through early

failure detection

Potential to reduce

environmental impacts

Potential to provide social

benefit

TECHNOLOGY RANKING (1 = Worst, 5 = Best)

AAcoustic instrumentation to monitor head loss/roughness/blockage

3 3 3 3 4 3 3 2 3 2 3 94 16 of 19

BFlow velocity monitoring to detect sedimentation

3 3 3 3 4 4 4 1 3 2 2 95 15 of 19

CFlow monitoring to detect blockage in gravity sewers (Penine Water Group, Univ Sheffield)

3 3 3 3 3 4 5 3 3 4 4 109 2 of 19

DReal time monitoring of dissolved Sulphide in sewers

4 4 4 3 2 3 2 2 5 2 3 102 10 of 19

EPressure transients to detect internal deterioration

4 4 4 3 2 3 4 3 4 2 3 108 3 of 19

FOptical fibre monitoring for structural condition (External)

4 4 4 3 2 2 4 4 4 2 3 108 3 of 19

GSoil temperature/moisture/pressure sensing to infer structural condition

4 4 4 3 3 4 1 4 4 2 3 108 3 of 19

HIn-situ Linear Polarisation Resistance to monitor soil corrosivity

4 4 4 3 2 3 1 3 4 2 3 99 12 of 19

ISurface based resistivity to monitor soil corrosivity

4 4 4 3 3 3 3 3 4 2 3 108 3 of 19

JContinuous monitoring of H2S gas in sewer networks

4 4 4 3 2 3 2 2 4 2 3 99 12 of 19

KStatistical inference monitoring of existing network data

3 3 3 3 3 3 5 3 3 4 4 106 8 of 19

LPump performance and condition monitoring (Yatesmeter)

3 3 3 3 4 4 1 1 3 2 2 86 19 of 19

MIn pipe sewage chemistry monitoring (CSIRO)

4 4 4 3 3 3 2 2 4 2 3 102 10 of 19

N Cathodic protection monitoring 4 4 4 3 4 4 3 1 4 2 3 108 3 of 19

O Infra-red thermography 4 4 4 3 1 2 2 2 3 2 3 90 17 of 19

P Real time hydraulic modelling 3 3 3 3 3 3 5 3 3 4 4 106 8 of 19

Q Real time water quality monitoring 3 3 3 3 3 3 2 2 3 2 3 88 18 of 19

R Permanent digital noise logging 3 4 3 3 4 3 3 3 4 4 4 110 1 of 19

S Ground penetrating radar 4 4 4 3 2 3 1 3 4 2 3 99 12 of 19

Prioritised IWN technologies• Top 6 IWN technologies from MCA prioritisation

“Detection” technologies to minimise operational response and social/environmental impacts of asset failures

“Predictor” technologies for early indication of deterioration and potential failure

Priority Tech ID Technology Description

1 R Permanent digital noise logging for leak detection in water mains

2 C Flow monitoring to detect blockage in gravity sewers

3 F Optical fibre monitoring for structural condition

E Pressure transients to detect internal deterioration

G Soil temperature/moisture/pressure sensing to infer structural condition

I Surface based resistivity to monitor soil corrosivity

Digital noise logging for water main leak detection

Cost-Benefit Analysis of Technologies• Following Multi-Criteria Assessment, a quantitative analysis also

undertaken for the most promising technologies• Intended to predict the financial impact on a water utility during

a pilot trial• Costs – capital, operating, maintenance, benefit realisation• Benefits – deferred capital, water saving, ‘tech replacement’

saving, reduced reactive maintenance, environmental and social benefits

Cost-Benefit Analysis of Technologies• For each technology, the benefit-cost ratio, net present value ($)

and return on investment (years) were assessed• Costs and benefits were calculated for a hypothetical trial area• A sensitivity analysis was also undertaken to identify

parameters that exert the greatest influence on NPV outcome

Cost-Benefit Tool: Example of Output

NPV outcomes most sensitive to reactive maintenance savings, but can be used to select

pilot trial areas

Cost-Benefit Analysis of Technologies: Recommendations

Tech ID Technology Description

NPV Sensitivity

Suggested pilot trial guidelines to maximise NPV25-Yr NPV (Average)

25-Yr NPV (High)

25-Yr NPV (Low)

R Permanent digital noise logging -$241,302 +$197,681 -$451,418

Large diameter, relatively old metallic mains in critical locations. This will target high consequence

mains and test hypothesis that noise loggers can provide early detection ability to pre-empt high

consequence bursts

Water mains constructed of MDPE. This will verify the enhanced performance of noise loggers in leak

detection for low stiffness, noise-attenuating materials where traditional leak detection is difficult.

FOptical fibre monitoring for structural

condition (External)+$26,513 +465,496 -$183,603

New pipe installations in high consequence areas. This presents an opportunity to investigate the

efficacy of external application of fibre optics on new mains without incurring the cost of exposing

mains and re-instating.

For Mild Steel mains, areas where stray current corrosion is possible, the installation of fibre optics

should be considered to detect leakage noise from localised corrosion in areas of coating breakdown

and inadequate cathodic protection

For GRP mains, fibre optics should be considered when bending stress from differential soil

movement is thought to be possible. Should also be considered for new installations where loss of

soil support and deflection thought to be possible.

Abandoned mains in low consequence areas. This presents an opportunity to investigate the

installation of fibre optics external to an existing buried main to detect changes in applied loads ahead

of failure.

ISurface based resistivity to monitor soil

corrosivity+$173,460 +$612,443 -$36,656

Large diameter, relatively old metallic mains in critical locations. This will target high consequence

mains and test the hypothesis that method can provide early detection ability to pre-empt high

consequence bursts

Long mains in areas of the network where localised saturated clay soils of low resistivity are thought

to exist.

Dr Joel ByrnesAssociate Director, AECOMt 03 9653 8466

0409 842 496 e [email protected]

Thank you