Water savings in the Goulburn Murray Irrigation District T he journey from 2000 to 2012
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Transcript of Water savings in the Goulburn Murray Irrigation District T he journey from 2000 to 2012
Water savings in the Goulburn Murray Irrigation District
The journey from 2000 to 2012
Stephen Harding and Ian MoorhouseIrrigation Australia Conference, Adelaide June 2012
Overview
> The water savings study in 2000
> What happened next?
> Where are we now?
> Lessons learned
The Goulburn Murray Irrigation District
Study objectives
> Reduce water losses by at least 50 GL
> Determine the volume of savings
> Quantify the initial and continuing costs
> Identify priorities for water saving measures
> Identify processes for verifying and quantifying water savings
System performance pre- Modernisation
Water Within the District
Goulburn component of GMID
Murray component of GMID
Total Goulburn-Murray Irrigation
DistrictAverage Inflows
Reduced Inflows
Average Inflows
Reduced Inflows
Average Inflows
Reduced Inflows
GL GL GL GL GL GL
Actual Diversions at river offtakes 1780 1350 1110 985 2890 2335On-Farm Metered Allocations to Irrigators 1305 932 715 623 2020 1555Losses due to System Inefficiency 475 418 395 362 870 780Total System Efficiency 69% 63% 67%
Ref: DSE, 2008
System losses
Key recommendations
1. Improve metering accuracy
2. Consistent framework for calculating efficiency
3. Confirm findings with further detailed studies
4. Resolve policy issues eg. savings from better measurement
5. Develop water conservation plans across the GMID
6. Address issues created by reduced outfalls
7. Adopt a strategic approach to modernisation investment
What happened next?
> “Millenium” drought
> Foodbowl modernisation initiative
> NVIRP project
10 Years of Drought
> Driest 10 yrs on record
> Involves adjusting climate model results to a local scale
> Usually involves use of local-scale historical data to ‘calibrate’ and ‘validate’ the model 10 Year Rainfall Deficiencies
1 Jan 1997 – 31 Dec 2006
Challenges with existing distribution network> Extensive spur channel supply system
o Long notice required for water orderso Variable flow rates and channel heighto Low flow rateso Manually operated Dethridge wheel outletso High water losseso Risks of high costs to maintain into the futureo Difficult to achieve the size of property required to
generate economies of scale
Foodbowl modernisation initiative
Benefits of modernisation> Remove most of the small local channels allowing properties
to be amalgamated and supply systems rationalised, with improved paddock access when G-MW channels are removed
> Provide a far higher level of service at the farm gate witho Water available close to on-demando Higher and more consistent flow rateso Modern, customer operated and controlled automated
outlets that can be integrated with on-farm systemso Improved 24/7 monitoring and responseo Best practice water delivery efficiency
Ref: DSE, 2008
Modernisation framework
Channel automation
Metering upgrades
Channel lining
NVIRP progress
Targeted investment approach
Lessons Learned
1. Clear vision and objectives – what are we trying to achieve?
2. Early stakeholders involvement and engagement
3. Good quality data is essential
4. Holistic approach that includes the supply system and on-farm
system
5. A sustainability based, strategic approach to investment
decisions
6. Real gains are possible both off- and on-farm
Summary
Biggest modernisation program in the world
Fundamental change in thinking
Far reaching consequences for irrigators,
communities and the environment
Significant benefits still to be realised on-farm