Upcoming irrigation water availability


 

 

Friday 16 September 2022

 

Upcoming irrigation water availability update

This aim of this service is to reduce some of the uncertainty about upcoming irrigation water availability in the connected southern Basin and to assist with earlier and more informed farm management decision making.

As a result of the current high water availability, this email service is only being provided on an as-needs basis this season, which is likely to be monthly.

In this update:

  1. Summary.
  2. Water commentary
    – Recent developments with Goulburn inter-valley trading.
    – Why big horticulture is below the Choke.
    – Check out BoM’s new water tools.
    – Cubby Station’s 30GL dam burst – photos.
  3. sMDB irrigation water availability.
  4. Yesterday’s allocation announcements.
  5. Recent storage inflows.
  6. Climate outlook
    – Climate drivers.
    – Seasonal rainfall outlook.
    – Seasonal climate update webinar.
  7. Seasonal streamflow outlook.
  8. Spills and deductions.
  9. Recent evapotranspiration (ETo) rates.
  10. Useful web sites.

 

1.  SUMMARY

  • Southern Basin irrigation water availability is currently above the same time last year, and well above the 5-year average.
  • The MDBA Active Storage volume is 8,315 GL (97% capacity), which is around its maximum volume with Dartmouth Dam, Hume Dam, Menindee Lakes and Lake Victoria all effectively full.
  • Water allocations on the Victorian Murray and Murrumbidgee systems increased with yesterday’s (Thursday’s) allocation announcements.
  • On the Vic Murray allocations increased to 100% HRWS plus 12% LRWS, while Murrumbidgee allocations increased by 1% to 47% General Security.
  • Significant allocation increases on the Murrumbidgee system will depend on demand and use of water creating airspace in storages, followed by further inflows.
  • In NSW, ongoing wet conditions are supporting supplementary access to water.
  • The additional volume required for a LRWS allocation on the Goulburn system is about 380GL, which is less than inflows into Lake Eildon during August 2022 (405GL).
  • As of yesterday (Thursday 15 Sept), 158GL of private water had spilled from spillable accounts on the Vic Murray, while 24GL of private water had spilled on the Goulburn.
  • The outlook for October to December is for greater than an 80% chance of exceeding median rainfall on the irrigated plains and upper-catchments, at this stage.

 

2.  WATER COMMENTARY

Recent developments with Goulburn inter-valley trading

A plan for delivering water from the Goulburn IVT account to the Murray in 2022-23 has been released to support implementation of the long-term operating and trade rules introduced on 1 July 2022.  In wet years, little water will be delivered from the Goulburn IVT Account because there is likely to be significant unregulated flows to meet demands for water in the Murray.  Each year, depending on the trigger for additional trade opportunity during spring, there is likely to be between 240 GL and 300 GL of new Goulburn to Murray trade opportunity.  There was around 205 GL of water carried over in the Goulburn IVT account into 2022-23.

Further trade opportunities from the Goulburn to the Murray system will be announced in mid-October and mid-December based on seasonal conditions. From December, net trade will be capped.

Changes have been made to Goulburn IVT trade processing for 17 October.  Allocation trade applications will be processed manually by the relevant water corporation.  Allocation trade applications need to be submitted between 10.00am and 10.30am through the MyWater and Broker Portal, and applicants will receive notification of the outcomes of trade applications, no later than 5pm, 17 October.

Why big horticulture is below the Choke

This MDBA report, “An Investigation into the Location of Horticultural Water Demands,” explains why horticultural developments are located where they are in the Basin.  Factors influencing horticultural developments below the Barmah Choke include optimal temperature and sunlight, rainfall during harvest, trafficability, and the proximity to processing infrastructure, services and labour.

Check out BoM’s new water tools

BoM have recently provided an interactive online service that generates maps showing projected changes in rainfall, run-off, soil moisture and evapotranspiration (ET), out to 2085.  This water projections product complements BoM’s existing historical and forecast water outlook service on their Australian Water Outlook web site.

A webinar focusing on new BoM products to help manage a LaNina summer, including forecasts of the chances of the wettest (or driest) deciles, is being held at 11.30am on Thursday 6 October.  This webinar is part of the ‘ForeWarned is ForeArmed’ project and is hosted by the Australian Wine Research Institute.

Cubby Station’s 30GL dam burst

Satellite photos show a dam wall at one of Queensland’s largest cotton farms has collapsed, creating a ‘lake’ of water and floating cotton bales.

 

3.  sMDB IRRIGATION WATER AVAILABILITY

The graph below shows total southern Basin irrigation allocations, plus irrigation carryover volumes, minus irrigation spill – summed for the Vic Murray, Goulburn, NSW Murray, Murrumbidgee and South Australian Murray.

*Victorian volumes included in the above graph (and table below) are “private” allocation and “private” carryover” volumes.  NSW volumes are “consumptive” allocation and “consumptive” carryover volumes.  South Australian volumes are “irrigation” allocations.  Environmental and urban volumes are excluded to better reflect irrigation water availability.  Irrigation spill volumes deducted are those from the Vic Murray and Goulburn systems.  Losses of water due to water use have not been deducted from volume totals. 

 

The MDBA reports that the MDBA Active Storage volume is 8,315 GL (97% capacity), which is around its maximum volume with Dartmouth Dam, Hume Dam, Menindee Lakes and Lake Victoria all effectively full.

 

4.  YESTERDAY’S ALLOCATION ANNOUNCEMENTS

Water allocations were updated yesterday, Thursday (15 September).

Key messages included:

Vic

NSW

  • General Security (GS) allocations on the Murrumbidgee system increased by 1% to 47% GS.
  • Significant allocation increases on the Murrumbidgee system will depend on demand and use of water creating airspace in storages, followed by further inflows.
  • Ongoing wet conditions are supporting supplementary access to water.
  • NSW Murray remains on 100% HS and 110% GS.  Source:  NSW DPE.

 

The table below shows updated irrigation allocations and irrigation carryover volumes for major sMDB systems.

Compared to this time last year:
– Irrigation allocations for the major irrigation systems are generally higher or equal (except for the Murrumbidgee where GS allocations are slightly lower this year), amounting to a total extra of 1,068GL.
– More irrigation water was carried over into this season (2022-23).  Originally, an extra 150GL of irrigation water was carried over compared to last season.  However, NSW Murray carryover is now considered forfeited and replaced by allocation, given the 110% GS allocation.
– Over-all, there is currently a total extra of 710GL of irrigation water allocated and irrigation carry over, compared to this time last year.
Volumes spilled to date from private spillable accounts reported by GMW are 158GL on the Vic Murray and 24GL on the Goulburn.

System CURRENT ALLOCATION

15 Sep 2022

LAST YEAR’S ALLOCATION

15 Sep 2021

CARRYOVER

into 2022-23

Estimated volumes

CARRYOVER into

2021-22

Estimated volumes

Vic Murray 100% HR.  12% LR 77% HR 388GL.  Private 423GL Private
Goulburn 100% HR 85% HR 629GL.  Private 489GL Private
NSW Murray 110%GS.  100%HS 44% GS.  97% HS 478GL (46% total).  Consumptive. 543GL (43% total) Consumptive
Murrumbidgee 47%GS.  95%HS 52% GS.  95% HS 396GL (28% total) Consumptive 316GL (22% total) Consumptive
South Australia 100% HS 100% HS
Estimated total irrigation volume  4,563GL      3,495GL 1,413GL.  Not including NSW Murray 1,771GL

Sources:  Vic NVRM web siteNSW Dept Planning, Ind & EnvSA Dept Env & Water.  

 

The current seasonal determination for the Campaspe is 100% HRWS, Broken 100% HRWS and 69% LRWS, Loddon 100% HRWS and Bullarook is 100% HRWS and 100% LRWS.

 

5.  RECENT STORAGE INFLOWS

The MDBA graph below shows 5 day rolling average inflows for the Murray system.  Murray inflows recovered from the ‘dry July’ and have been well above the long-term average during August and September.  The MDBA reports that Murray system inflows for August were around 2,260 GL, which is within the highest 22% of inflows on record for August.

Source:  MDBA Weekly Report.

Lake Eildon inflows also recovered from the “dry July”, and in August were well above average and approached the wet scenario, as shown in the graph below.

Source:  NVRM.

6.  CLIMATE OUTLOOK

Climate drivers

Earlier this week, BoM announced that a La Nina had established.  Models indicate this La Niña event may peak during spring and return to neutral conditions early in 2023.

The negative Indian Ocean Dipole (IOD) continues.  Climate models indicate the negative IOD conditions are likely to continue into late spring. A negative IOD event is typically associated with above average spring rainfall for much of Australia. When a La Niña and negative IOD combine, it further increases the likelihood of above average rainfall.

Source:  BoM.

 Seasonal rainfall outlook

BoM’s outlook for the rest of September (19 Sep – 2 Oct) is for greater than 70% chance of exceeding median rainfall on much of the irrigated plains.

Yesterday BoM updated their climate outlook.  The outlook for October to December is for greater than 80% chance of exceeding median rainfall on the irrigated plains and upper-catchments, as shown in the coloured map below.

The chance of above median rainfall for October to December

Source:  BoM.

Seasonal climate update webinar

Yesterday’s ‘Seasonal Climate Update’ webinar with AgVic’s Dale Grey, is now available for Victoria, southern NSW and South Australia.

 

7.  SEASONAL STREAMFLOW OUTLOOK

The Streamflow Outlooks for September to November for Lakes Dartmouth, Hume and Eildon are all for high to median inflows.

Source:  BoM.

Streamflow outlooks for other storages and rivers can be obtained from the BoM Seasonal Streamflow Forecast web site.

 

8.  SPILLS AND DEDUCTIONS

All major storages across northern Victoria are approaching capacity, but with this comes releases and spills.

In yesterday’s northern Victorian Seasonal Determination announcement, it was reported that 100% of the allocation held in Vic Murray spillable accounts would be deducted with yesterday’s update, while about 31 gigalitres (about 8%) would be deducted from Goulburn spillable water accounts.   Also, “releases to manage Lake Hume and Lake Eildon levels will continue for some time, and Murray and Goulburn system entitlement holders can expect further deductions from spillable water accounts this year.”

As of yesterday (Thurs 15 Sept), 158GL of private water had spilled from spillable accounts on the Vic Murray system, while 24GL of private water had spilled on the Goulburn.  SourceNVRM.

In the “Current Risk of Spill” update issued earlier this week on Monday 12 September, it was announced the risk of spill from Lake Eppalock (in the Campaspe system) had increased to about 40 percent.

 

9.  RECENT ETo

Over the past 7 days ETo (evapotranspiration) has ranged from 0.6mm/day to 2.5mm/day, or an average of 1.9mm/day, at Kyabram.  For a reference crop of pasture, an average ETo of 1.9mm/day requires a surface irrigation interval of about 23 days – in the absence of rain!

  

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USEFUL WEB SITES – for more information related to upcoming irrigation water availability

 

Rainfall

Recent rainfall.  Map.  Rainfall for the past day, week or months.  BoM.

Recent rainfall.  Map.  Australian weather stations.  Daily, weekly, monthly rainfall all years. BoM.

Recent rainfall.  For select Victorian locations.  Past 7 days. BoM.

Rainfall since 9am.  Updated every half hour.  For select locations.  Rainfall (temperaturre and wind) shown on map as coloured text.  Click on “weather observations” (bottom right of screen).  Double click on the weather station (location) on the map for more details.  “Rain radar” web site.  BoM.

Forecast rainfall.  Map.  For next 4-day or 8-day period, or for any particular day over the next 5 days.  BoM.

Forecast rainfall.  For nominated locations. 7-day outlook.  Forecast rainfall (wind and temperature) given in 3-hour windows.  “MetEye” web site.  BoM.

MDBA Weekly River Murray Report.  Provides a weekly review of rainfall and lots of other important updates for the connected southern MDB.

 

Streamflow response and inflows

Murray system.  MDBA Weekly Report.  Inflow graphs are at the back of the report.  Compares recent inflows with long-term averages.  Weekly streamflow response commentary is also provided at the front of the report.

Murray system.  Click on a site (eg.Hinnomunjie or Jingellic) and select the “Flow” tab.  Updated daily.  MDBA.

Goulburn system.  Doherty’s, Jamieson, Gerrans Bridge and Glen Esk are some monitoring sites above Lake Eildon.  Updated daily.  GMW.

Goulburn Murray storage inflow data.  Graphs of relative monthly inflows.  Analysis of monthly and year-to-date inflows.  NVRM.

Campaspe, Broken, Loddon, Ovens and Kiewa Basins.  Updated through the day.  GMW.

River flood condition.  Current.  Graphs of recent river height relative to minor, moderate and major flood levels.  BoM.

Flood class level.  Shows minor, moderate and major flood levels for different monitoring sites.  BoM.

Annual streamflow differences and streamflow data.  For many Australian locations (“Hydrological Reference Stations”.)  Daily, monthly and annual streamflow data and analysis.  BoM.

Water data online.  Shows flow data (often measured as cubic metres per second “cumec”!) and useful analysis including monthly mean flows for hydrologic reference stations around Australia.  BoM.

Surface water monitoring sites.  Vic.  Stream level.  Streamflow data and reports.  DELWP.

Streamflow – NSW.  Shows current, historical and forecast flow rates and river levels for NSW river gauges.  (Select a location on the map and choose the “gauges” tab.)  Water Insights.  WaterNSW.

Past, current, forecast and projected run-off maps.  Forecast – for each of next 3 months.  Projected – 2030, 2050, 2070 and 2085.  BoM – AWO.

Past, current, forecast and projected evapotranspiration maps.  Forecast – for each of next 3 months.  Projected – 2030, 2050, 2070 and 2085.  BoM – AWO.

 

Streamflow forecasts

Seasonal streamflow forecast.  Up to 3-month forecast.  eg.  Forecast inflows for Lakes Hume, Dartmouth, Eildon, Eppalock or Nillahcootie.  BoM.

7-day streamflow forecast.  eg. For locations in the upper-Murray, upper-Goulburn, Campaspe or Loddon.  BoM.

Murray system.  Click on a site (eg. Hinnomunjie or Jingelic) and select the “Flow Forecast” tab.  7-day forecast.  MDBA.

 

 

Catchment condition

Current relative long-term rootzone soil moisture.  Map and graph.  eg. Type “Upper Murray River,” “Goulburn River” or “Broken River” into the Search Bar.  BoM.

Historical, forecast and projected soil moisture.  Forecast – for each of next 3 months.  Projected – 2030, 2050, 2070 and 2085.  BoM – AWO.

 

Seasonal water determinations

Current Northern Vic allocations.  Current allocations for the different Northern Victorian irrigation systems.  NVRM.

Historical Northern Vic allocations. Historical allocations data for the different Northern Victorian irrigation systems, back to 1994-95.  NVRM.

Current and historical NSW allocations.  Water Alloction Statements, iIncluding NSW Murray and Murrumbidgee.  DPIE.

Current and historical SA allocations.  Water Allocation Statements and pre-season announcements.  DEW.

MDBA Weekly River Murray Update.  Summary of current water allocations for different vallies in the sMDB, usually on the last page of the report.

 

Water allocation outlooks

Northern Vic.  Current outlook for the different Northern Vic irrigation systems.  NVRM

NSW.  Includes NSW Murray and Murrumbidgee.  The water outlook is included in the relevant Water Allocation Statements, usually on the back page of the report.  DPIE.

Northern Vic Water Balance (“rocket”) diagrams.   Graph showing a breakdown of the water in store and water commitments, for each Northern Vic irrigation district.  NVRM.

 

Climate outlook

Climate outlook.  Weeks, months and seasons.  BoM.

Climate Driver Update.  Over-all summary.  Pacific Ocean.  Indian Ocean.  Southern Ocean.  Sea surface.  Issued fortnightly.  BoM.

Outlook scenario for rainfall amount.  Map showing chance of rainfall amount for next week, fortnight, month or 3-month period.  BoM.

Chance of at least (rainfall).  Map showing probabilities of receiving a specified amount of rain for next week, fortnight, month or 3-month period.  BoM.

The Fast Break.  A farmer-oriented update of seasonal climate drivers and outlooks, including a summary of rainfall predictions for the next 3 months from 12 different climate models.  AgVic.

Climate driver tool.  Interactive tool that enables you to explore how rainfall at your selected location has been influenced by different climate driver phases, in the past.  The tool also provides analysis of long-term rainfall records.  AgVic, GRDC and SARDI.

 

Weather warnings

Victorian warnings.  Summary of valid weather warnings issued, including floods.  BoM.

River Height and flood class.  Provides data on current river height, flood class and whether rising, falling or steady.  Table and graphs.  BoM.

Streamflow flooding and recent rainfall.  Shows river condition (flooding) for monitoring sites across catchments.  Map.  BoM.

 

Water storage

MDBA River Murray Weekly Report (produced on Fridays):
– Graph showing ‘MDB Active Storage’, recent and over the last 20 years.  This graph only appears monthly, usually in the first week of the month
– A summary of storage volumes and weekly volume changes for southern MDB storages are given in tables (usually on about page 3).

Northern Vic Resource Manager.  Provides a breakdown of volumes currently available in allocation accounts, new allocation volumes in the current season, volumes carried over into the season, volumes in spillable accounts and net trade – for each irrigation district and for private, environmental and Water Corp holdings.

Goulburn Murray storages.  Shows current storage levels, weekly change and storage at the same time last year,  for Murray, Goulburn, Ovens, Broken, Campaspe, Loddon and Bullarook storages.  Graphs of storage levels this year, compared to previous years are shown.  Updated regularly.  GMW web site.

Goulburn Murray storages.  Shows storage level graphs and data for Murray, Goulburn, Ovens, Broken, Campaspe, Loddon, Kiewa and Bullarook storages.  Updated every 15 minutes.  GMW.

Goulburn Murray storages.  Shows graphs and data for observed volume, level and percentage full for GM storages.  (Select ‘System Status Report’, choose which ‘Basin’, select ‘Storage’, then select your storage.) GMW.

Murray storages.  Click on the storage (eg. Hume Dam) to get ‘percent full’ and current storage volumes.  This site is regularly updated.  MDBA.

Murray Darling Basin storages.  Shows ‘percent full’ figures for storages in the Basin.  Also provides ‘percent full’ for ‘Southern Basin total.’  Updated fortnightly.  The fortnightly MD Basin Storage Report featuring a map with current MDB storage volumes, can be downloaded from this page.  MDBA.

Murray Darling Basin storages.  Shows dam volume and ‘percent full’ figures for Basin storages, different systems (eg. Murray and Goulburn) compared to last year, and a break-down of how the water is shared (eg. private, environment, water corporation).  Updated regularly.  BoM.

NSW storages.  Provides “percent full”, current volume, inflow and release data for NSW storages.  Updated regularly.  (Select a location and the “storage” tab.  Water Insights – WaterNSW.

Archived Basin storage reports.  Provides an archive of fortnightly reports showing MDB water in storages, back to 2009.  MDBA.

 

Carryover volumes

Northern Vic Resource Manager.  Shows carryover volumes for each (Northern Vic) irrigation district.

NSW.  Carryover percentages for NSW Murray and Murrumbidgee systems are usually included in the Water Allocation Statements (usually in a table on page 1).  DPIE.

  1. SA. Developments regarding SA carryover and whether or not it is available in an irrigation season, are typically found in the pre-season announcements.

Vic Carryover Tool.  To help you work through carryover scenarios for your unique Vic farm situation.  DELWP (Vic Water Register).

 

Water availability

Unused water – Vic.  Shows volume of carryover, allocation, use, net trade, write-off and a graph of unused available water in recent seasons for each northern Vic valley.  Vic Water Register.

Available water by owner type – Vic.  Shows carryover, allocation, trade and spill volumes for Vic valleys. Private, environment and Water Corp ownership categories.  Current and previous years.  Scroll down for Further Insights.  Vic Water Register.

Water allocated and used – NSW.  Shows the volume of water allocated and used against entitlement type and ownership class.  This information is shown for the current year or previous years. (Select a location and click on the “allocation” or the “historical” tab.)  Water Insights.  WaterNSW.

River Murray flow and use in SA.  Shows river flow into SA and a break-down of water use.  Updated quraterly.  SA Dept of Env and Water.

River Murray Water Calculator – SA.   Shows SA allocation and entitlement volumes for different water classes under different water availability scenarios.  SA Dept of Env and Water.

 

District water use and trade – Northern Vic

District Water Use.  Water used in different Northen Victorian irrigation districts by private, environment and water corp owners.  NVRM web site.

Net Trade for Districts.  Trade in and trade out, for different Northen Victorian irrigation districts by private, environment and water corp owners.  NVRM web site

Water available by owner type.  Vic district carryover, allocation, trade and spill volumes.  Vic Water Register.

 

Risk of spill announcements

Northern Victorian Resource Manager.  Sometimes the Vic risk of spill information is included in the Seasonal Outlook announcements.

 

Current state shares in Murray storages

MDBA Storages.  Displays the shares of the MDBA “Active Storages” (Lakes Hume, Dartmouth, Menindee and Victoria) for Vic, NSW and SA.  This site also shows the relative “air space” for each share (Vic, NSW & SA).  Scroll to the bottom of the page and click on the PDF for the latest update. MDBA.

 

Intervalley trade (IVT)

Goulburn IVT 

Opportunity for allocation trade.  Interactive tool.  Vic Water Register web site.

Planned monthly IVT transfers.  Scroll down to the heading “Planned Inter-Valley Trade Transfers.”  GMW web site.

Goulburn to Murray trade rules.  Be carefult to stay informed about the latest changes to Goulburn to Murray trade rules.  Vic Water Register web site.

Barmah Choke

Barmah Choke trade balance.  Current and historic trade balance data.  MDBA web site.

Allocation trade opportunity.  Interactive tool.  Vic Water Register web site.

Murrumbidgee IVT

IVT Status.  Provides the current Murrumbidgee IVT Account Balance, whether trade is open or closed and backgound information.  WaterNSW site.

Annual plan for MDB IVT

MDBA River Murray System Annual Operating Outlooks. Outlines potential forward scenarios of IVT delivery for the irrigation season ahead – which can be useful if you want to gain a better understanding of how much water may be traded out of different valleys in the remainder of the season.

 

Water Market Outlook

ABARES Dashboard.  Water Market Outlook for sMDB water allocation prices in 2021-22 for wet, average and dry scenarios.  Water market reports are also provided.

 

Water market updates

Subscribe to these weekly water market reports:

Weekly Water Market Report.  H2OX.

Weekly Newsletter.  Ruralco.

Weekly Water Report.  Waterfind.

Weekly Water Wrap.  Waterpool.

 

Aither also produce Monthly Water Market Insights (fee for service) and other water market reports.

 

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This publication is provided solely for information purposes and no representation or warranty is made as to its quality, accuracy, completeness, suitability or fitness for any particular purpose. You should make your own inquiries as to its appropriateness and suitability for your particular circumstances.  The State of Victoria as represented by its Department of Jobs, Precincts and Regions accepts no duty of care and disclaims all liability in relation to use of this publication.

Information in these updates is provided to assist irrigators make more informed and earlier farm maangement decisions related to upcoming irrigation water availability.  The information is NOT intended to assist with financial decision making related to water investment or water trade.

Due to a need for the release of timely information, this report is not subject to rigorous checking and approval procedures.  Figures provided in this report are entered manually and are subject to error.  Information in this report needs to be checked with other sources.

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