Lake Wyangan ProjectDave Gilbert and Chris Green

IA Conference 2014

The Murrumbidgee Irrigation Area (MIA)

Infrastructure Modernisation

Improve delivery system efficiencies Meet changing customer needs Reduce asset ownership costs Generate water savings Reduce infrastructure

footprint

Key Objectives

Lake Wyangan System

Closed system within a catchment of 7,000 ha Irrigation supplies to around 200 properties Ageing concrete-lined gravity supply channels Constrained system

limited to 220 ML/day Mix of hobby blocks,

horticulture and large area Social amenity provided

by Lake Wyangan

Background

Lake Wyangan Project Area

Lake Wyangan Project

Replace ageing infrastructure that is at risk of failure Enable delivery of contracted levels of service Minimise the impact on water levels and water quality and

the overall environmental health of the Lake Wyangan catchment

Realise the estimated water savings target for the project

Objectives

Lake Wyangan Project

Upgrade the existing supply system – Focus on renewal of ageing assets over water savings

Reconfigure the existing system – Focus on providing a secondary supply system for some areas

to address capacity constraints Build new assets to alleviate

requirement to upgrade some capacity constraints – Focus on creating new asset over

renewal of existing assets

Options considered

Lake Wyangan Modernisation

Reline and widen 15.8km of ageing concrete-lined Lake View Branch Canal (122,000 sq. m of shotcrete lining)

Replace open channels and pipelines at the end of their working lives with 13.8km of GRP and PVC gravity pipelines

Replace Dethridge wheels with electromagnetic flow meters compliant with AS4747

Automation of regulators and escape structures Install remote monitoring of flow

meters

Scope

Existing Channel Lining

Assessment of Existing Lining

1 2 3 4 5 6 7 8 9 101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263640%

20%

40%

60%

80%

100%

120%

Percentage of Collapsed and Failed Panels

Failed Panels

Collapsed Panels

Sector Number

Perc

enta

ge o

f Pan

els

Lining Design Criteria

Convey the required flow Construction within winter

shutdown periods Reduce seepage losses Prevent erosion / dispersion

of soil behind lining Durability for 80 years

design life Cost-effective solution

Ranking Fibre reinforced shotcrete Grouted fabric mat Shotcrete over sealed liner Coletanche (geotextile) with

asphalt / bitumen Shotcrete over a flexible

membrane Hypalon HDPE

Design Criteria

Technical Risk Reduction

Earthwork remediation and compaction Concrete mix and curing

– Unreinforced v. polymer reinforced shotcrete Shotcrete application

– Shotcrete lining over a geotextile Panel contraction and expansion

joints Lining detail at bank top Shotcrete surface finish

Shotcrete Lining Trials

Channel Re-lining

Channel Re-lining

Construction Schedule

Timing May 2013 –Nov 2014 Nov 2013/Nov 2014

Planning options

Survey and detailed design

Outlet designs

Stakeholder forums

Individual face-to-face meetings

Construction:

– Civil

– Mechanical

– Electrical

– Automation

Acceptance testing

New system begins operation

Key steps

Oct 2011– ongoing Oct 2011 – May 2013

Planning and design

Construction Testing/ Commissioning

Building relationships

Lake Wyangan Modernisation

Forecasting future customer behaviour and intentions Managing customer expectations Developing and adopting new design rules Establishing new business processes Anticipating changes to operating

practices Compressed construction window Delivering a successful project for

MI, customers and the region

Challenges

Acknowledgement

The Lake Wyangan Modernisation Project received Australian Government funding

of $50 million through the Private Irrigation Infrastructure Operators

Program in NSW

Thank You for Your Attention