Back to Allocations

Allocations – Bacchus Marsh & Werribee

High Reliability
100 %
Low Reliability
100 %

The allocation does not include any carried over water from last season.

Allocation is reviewed every fortnight and decisions are announced via this website, SMS, social media and sometimes by media release.

  • Allocation

    Every year, we set allocation levels for the western irrigation business, which tells customers what percentage of their river water entitlement they can take. This is separate to any recycled water entitlements.

    Southern Rural Water announces allocations every fortnight.

    A season lasts 12 months, from 1 July to 30 June.

  • Carryover

    This means that we will start the new system on 1 July. As a result, any unused water in your allocation account (ABA) at the end of this season on 30 June will automatically carry over to the next season, starting on 1 July.

    You need to have a water share linked to your allocation account to be able to carry over your unused water.

    How can you use carryover?

    Carryover gives you more flexibility to:

    • hold, use or trade water when it’s of the greatest value to your business; and
    • prepare for drought by holding enough water for use in the next season.

    Will there be much change?

    Carryover helps you manage your water to meet your business requirements. However, there will be small differences to allocations compared to the current system.

    At the start of a new season, we will calculate the volume of water carried over from the previous season. Then if there is more water held in the reservoirs than is needed to deliver the carryover, we will announce an increase to that season’s allocation.

    This means that in most years, the starting allocation may be lower than under the current system.

    If you use all of your water and do not carry over, then you may have less water at the start of the year. In normal years, this will even out as the season progresses, with increases in allocations going to those who have room in their entitlements.


    When you can carry over water from season to season, buying and selling water may be an important option for you to secure the right amount of water for your ongoing needs.

    If you have a Facebook logon you can lodge a post on the relevant group.  If you don’t have access to Facebook, contact the Customer Service team on 1300 139 510 and they can post on your behalf.

    Please note that if you want to trade water before the end of the season with the aim of carrying over any unused water, then you need to lodge your applications with us before 23 June to give us enough time to process it.

    How will at affect me?

    Below are a couple of examples of how carryover works.

    If you want to understand how carryover might affect your circumstances, please call us and make an appointment so we can explain how it will work in your business.

    Carryover:  Farmer A

    • Farmer A has a high reliability water share of 20ML and low reliability water share of 10ML
    • Allocation this season is 100% high-reliability and 15% low-reliability. This equals 21.5ML of water for farmer A (20ML of high reliability and 1.5ML of low reliability)
    • Farmer A uses 11.5ML of water in the season and so there is 10 ML of unused water
    • Farmer A carries over 8.5 ML of water to the next season. This is the 10 ML unused water minus 15% for evaporation loss, which is 1.5ML
    • Starting allocation for the following season is 40% high-reliability
    • Farmer A has 16.5 ML of water available for the start of the next season, made up of 8.5ML carried over from previous year, and 8ML of new season allocation (40% of their 20 ML high-reliability share)
    • As the reservoirs fill, Farmer A will receive further allocation increases up to a maximum of 13.5 ML – when he will have 30 ML of water which is the maximum under his water shares (20 ML high-reliability and 10 ML low-reliability).

    Carryover: Farmer B

    • Farmer B has 200ML high reliability water share and 100ML low reliability water share.
    • Farmer B uses 200ML of water in the season and so there is 15ML of unused water
    • Farmer B carries over 12.75ML of water to the next season. This is the 15ML unused water minus 15% for evaporation loss, which is 2.25ML
    • Starting allocation for the following season is 40% high-reliability
    • Farmer B has 92.75ML of water available for the start of the next season, made up of 12.75 ML carried over from previous year, and 80ML of new season allocation (40% of their 200ML high-reliability share)
    • As the reservoirs fill, Farmer B will receive further allocation increases up to a maximum of 207.5ML – when he will have 300ML of water which is the maximum under his water shares (200 ML high-reliability and 100 ML low-reliability)
  • Data that we use to work out allocations amounts

    We use a range of data to work out the amount of water we can allocate. Some of this is actual data and some of it is assumed data.

    Actual data


    Reservoir Maximum capacity SRW’s share Other shareholders Dead storage
    Pykes Creek 22,119 megalitres (ML) 99.74% Greater Western Water 0.26% 1922 ML (in drought, SRW can use floating pumps to reduce dead storage to 468 ML)
    Melton 14,364 ML 100%   141 ML
    Merrimu 32,516 ML 20% Greater Western Water 80% 570

    High and Low Reliability Water Shares

    The figures for these are in the Victorian Water Register and our Irrigation Planning Module (IPM).

    Total usage to date

    This figure comes from the IPM system. It includes data from meter readings, usage estimates since last meter readings, and orders lodged in the system.

  • Assumed data


    We assume that we are able to harvest all flows into both Pykes Creek and Melton Reservoirs, other than the legal passing flows.

    Flows into Merrimu are shared between Southern Rural Water, Greater Western Water and the State Government.


    We use a model to work out evaporation, based on average evaporation, area of storage and a 12-month period.

    Delivery and river transfer losses

    Delivery and river transfer losses can vary considerably, depending on weather, leakage and demand.

    Unused entitlement

    At the end of the season, any unused water is either carried over by an entitlement holder or forms part of the opening allocation at the start of the new season.

    Guaranteed inflows

    Guaranteed inflows are estimated by skilled staff.

  • Watershare & allocation trading

    Why trade water?

    Water in the Werribee and Bacchus Marsh Irrigation District is fully allocated; therefore no new water is available.

    To help make the most of water on hand, we ask anyone who does not plan to use their water to consider trading to others in the area.

    Water trading can help to:

    • reduce your water bill
    • provide additional income
    • maximise productivity for the district
    • build the local economy.

    As a purchaser, water trading can help to meet your needs during a dry spell, or when your existing allocation is not enough.

    What types of trades are available?

    Allocation trade

    You can trade any unused allocation from your Allocation Bank Account (ABA). These trades are for one season only and finish on 30 June each year. Water must be used by 30 June in the season in which the trade occurred. If this water remains unused at 30 June it will be returned to the communal pool for allocation the following year.

    Limited term transfer

    This is where you lease your water share to someone else for a set period of time. The transfer period can be from 1 year to 20 years, and the transfer does not change the legal ownership of the water share, A Limited Term Transfer will remain in place until it expires or is surrendered; even if the water share is transferred permanently (see below).

    The lessee is called the holder of the Limited Term Transfer, and is the only person who can surrender or cancel the Limited Term Water Share Transfer before its expiry date. Any allocations held by the seller at the time of the transfer remain in the seller’s ABA, but can be traded by the seller via an Allocation Trade (see above). Any further allocations will be added to the holder’s ABA.

    Permanent transfer

    This is when you sell all or part of a water share. The legal ownership of the water share changes, but any existing Limited Term Transfers against that water share will remain in place until they either expire or are surrendered.

    Delivery share transfer

    This is the permanent transfer of all or part of your delivery share. Restrictions apply where a delivery share can be traded within the district, as they directly relate to and influence the capacity of each of the delivery systems in the district.

    How are prices set for water trades?

    The price for the water needs to be negotiated between the seller and buyer. Southern Rural Water does not play a role in trading price negotiations.

    Statistics on past trades and transfer prices can be obtained from the Victorian Water Register

    Are there any application fees?

    For information about fees, please contact us on 1300 139 510 or visit our Prices and forms page.

    How can I find a buyer or seller of water?

    There are many ways to find buyers and sellers of water. You could advertise in the local paper, talk to your neighbour or use a trading exchange.

    Water trading exchanges operate throughout Victoria and link buyers and sellers who have lodged compatible bids. The following trading exchanges operate in our irrigation areas:

    Waterfind –

    More information
    For more information contact us on 1300 139 510

    Download BMID & WID allocation fact sheet