Social and economic impacts of the Basin Plan in Victoria February 2017



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9.2The nature of the problem


Before the unbundling of water entitlements in Victoria in 2007, all water entitlements were tied to specific parcels of land and the spatial distribution of these entitlements provided a good guide to where the water was most likely to be used. Now around 7% of all entitlements are not tied to land, but for the time being the spatial distribution of the remaining entitlements still provides a reasonable proxy for where they are most likely to be used.

In that context it is important to note that between 30 June 2001 and 30 June 2015 the volume of high reliability entitlements ‘tied to land’ in the GMID decreased from 1,648 GL to 992 GL, a 40% decrease (TC&A 2016, Table 5). The decrease includes a contribution to the system-wide movement of 175 GL of privately owned entitlements no longer tied to land. Allocations against a large proportion of these ‘not tied to land’ entitlements will be used in the GMID in many years – if this were to be apportioned between LMW and GMW diverters in the same ratio as entitlements currently tied to land it would amount to 116 GL15. A more realistic estimate of High Reliability Water Shares supporting irrigated enterprises in the GMID is therefore 1,108 GL, a 33% decrease since 2001.

To put this in perspective, this 540 GL reduction is greater than the volume of all high reliability entitlements held in the Murray Valley and Loddon Valley (formerly Pyramid-Boort) Irrigation Districts in 2001. The key difference in this comparison is that rather than being concentrated in a small number of locations, the purchases have been scattered throughout the GMID (Figure ). Because the changes in GMW customers’ water demands are spread throughout the network, opportunities to rationalise the network are much harder to identify and realise than they would have been had the transfers been concentrated in discrete areas.

Figure – Spatial distribution of water entitlements traded to the Commonwealth from farms in the GMID

Reduced water deliveries, and a potential reduced customer base, are resulting from:


  • Commonwealth acquisition of High Reliability Water Shares for the environment

  • Entitlement trade to LMW diverters to support continued horticultural expansion

  • Decreasing water availability resulting from climate change.

When entitlement trade out of irrigation districts was first allowed, there was an annual 2% limit on the total volume that could be traded out in any one year. This was intended to slow the rates of change in order to give communities time to adjust. This was lifted to 4% under the National Water Initiative, and was eventually abolished in order to comply with the Basin Plan Water Trading Rules in July 2014. While the limit was in place Victoria allowed exemptions to target Commonwealth water purchases to less productive areas or areas where infrastructure was being rationalised to avoid the loss of water in modernised areas and improve regional productivity (DSE 2009 and GMW 2016c). However, the abolition of the limit rendered those efforts largely unsuccessful.

Any reductions in water availability associated with climate change will compound the challenges posed by this reduction. Long-term reductions in water availability associated with climate change are uncertain, but under a medium climate change scenario DSE (2008) estimated water availability would decrease by around 25% by 2055. GMW (2016a) assumed a reduction of 20% in historic flows for the purposes of estimating deliveries for the most recent price review.


9.3Future outlook


Buybacks, trade out of the district and the drying climate are expected to result in significantly lower water deliveries in the GMID. GMW (2016a) estimates that water demand in the GMID over the next eight years will be in the order of 1,150 GL per year. This assumes no further impact on High Reliability Water Shares from Commonwealth water recovery programs, and no further purchases from LMW’s customers or horticultural developers in NSW or South Australia, but it does assume a 20% reduction in historical inflows due to climate change.

In the long term, average deliveries in the GMID are expected to be in the order of 1,200 GL16. This is 41% lower than long-term average deliveries of 2,020 GL modelled for Stage 1 of the Connections Project (NVIRP 2010, Table 2-2). In effect the Commonwealth’s water recovery from off-farm infrastructure investments has been working at cross-purposes with its water recovery from buyback. On one hand the off-farm infrastructure investments have been providing more efficient services, on the other hand buyback has rendered those modernised services less cost effective.

Reduced deliveries are a major challenge to GMW because its extensive asset base requires routine annual maintenance, operations and renewal. Therefore, its costs are largely fixed. Consequently the average cost of maintaining the delivery infrastructure goes up as the volumes being delivered go down.

GMW has few options for managing the risk of reduced deliveries other than to design a tariff system that is predominantly based on fixed charges. These tariffs are vetted by the Essential Services Commission and seek to provide cost reflective pricing. While GMW’s revenue is secure under the current arrangements, the marginal benefits its customers derive from its services are going down as total deliveries go down, and the effective price they pay to use each ML is going up. This is especially the case for those of its customers who have sold entitlements and wish to irrigate opportunistically when allocation prices are low.

Up until 2005/06 there was a close alignment between the volume of water entitlements tied to land in the GMID and the volume delivered. As illustrated in Figure , the volume delivered was relatively lower during the height of the drought, but it has been relatively higher than entitlement volume since the drought broke; this is the combined result of the breaking of the drought, entitlement trade to LMW diverters, buyback, and the ability to hold water entitlements now without linking them to land.

Figure : High Reliability Water Shares linked to land and water use in the GMID 2000/01 to 2014/15

Source: TC&A 2016 and GMW Annual Reports.

Figure shows that another important relationship has also changed over a similar period. The number of GMID delivery shares created at the time of unbundling was directly related to the number of High Reliability Water Shares linked to land in the GMID at that time. While the number of those water shares has since dropped by more than 35%, for the combination of reasons outlined above, the number of Delivery Shares, against which GMID irrigators pay their fixed charges, has dropped by less than 5%.



Figure : Change in Delivery Share and High Reliability Water Shares in the GMID relative to 2008/09 levels

Delivery Shares were initially designed as an instrument to ration the capacity of the delivery system during times of peak demand, but now that the off-farm infrastructure has been modified, rationing is now largely no longer necessary. Delivery Shares are now artefacts that reflect how much benefit landholders could derive from their access to the delivery system. As can be seen in Table , GMW’s Infrastructure Access Fee, which is charged per Delivery Share, makes up the bulk of its customers costs of irrigation supply.

Table – Breakdown of charges for a large irrigation customer in GMID – fixed charges are shaded blue



Fees

Charge per unit

Charge subtotal

Proportion of total charge

Entitlement Storage HRWS ($/ML)

$10.57

$4,333.70

13%

Entitlement Storage LRWS ($/ML)

$5.18

$-

0%

Service Point Remote Operate ($/service point)

$400.00

$800.00

2%

Infrastructure Access
($/Delivery Share)

$4,454.00

$20,933.80

62%

Infrastructure Use ($/ML)

$9.34

$3,829.40

11%

Surface drainage service ($)

$100.00

$100.00

0%

Surface drainage area ($/ha)

$11.73

$1,524.90

5%

Surface drainage Water Use ($/ML)

$5.60

$2,296.00

7%

TOTAL




$33,817.80

100%

Source: Fees from GMW Pricelist 2015/16

When Delivery Shares and the Infrastructure Access Fee were introduced there was some expectation that as irrigators sold entitlement they would trade or retire delivery share. As will be discussed further below, this has not turned out to be the case. As a proportion of 2008/09 levels, High Reliability Water Shares have decreased by 37% and delivery share by 4% (Figure ). Changes in water deliveries are more complex to analyse as seasonal conditions affect both allocation and use levels, as does the use of carryover and allocation trade. But over the long-term average water use is expected to decline in similar proportions to High Reliability Water Shares, unless there are allocations against Low Reliability Water Shares or allocations can be traded from NSW, LMW or South Australia.

The ratio of High Reliability Water Shares to Delivery Shares in the GMID has decreased from close to 90:1 in 2009 to 60:1 in 2016 (Figure ). Large customers with similar changes in their own ratios would see their effective charges per ML of HRWS increase (Figure ).

Figure : Ratio of High Reliability Water Shares to Delivery Shares and the percentage increase in Large Customer charges per ML of HRWS as HRWS is sold

Source: Delivery Share data provided by GMW.


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