Water Market Update: May 2026

Market snapshot

The WY2025/26 irrigation season is effectively over, but prices are not easing the way a normal late season would: carryover demand ahead of 30 June is holding the market at or near season highs — the same late-season dynamic Ricardo flagged across the southern Basin in 2024-25. Year-to-date VWAP sits at $258/ML for Zone 1A — the highest season average since WY2019/20.

Zone	Season VWAP ($/ML)	9-month volume (GL)
Zone 1A (Greater Goulburn)	$258	234
Zone 6 (Murray above Barmah)	$267	109
Zone 7 (Murray below Barmah)	$282	142
NSW Murray	$237	384
SA Murray	$291	96

To understand what drives prices, see our water pricing guide.

Allocation announcements — season wrap

Victoria

Final NVRM determinations for WY2025/26:

• Goulburn HRWS: 73% (final). Opened at 31% on 1 July, reached 62% after November rain, then crept up as updated carryover data freed more water.
• Murray HRWS: 100% (reached 17 November 2025). Opened at 39%.
• Goulburn LRWS: 0% all season — no low-reliability water issued.
• Murray LRWS: 0% — like the Goulburn, no low-reliability water was issued this season.

The Goulburn system stalled at 73% — Eildon inflows were below expectation throughout the season. No LROS (Low Risk of Spill) declaration was issued, meaning carryover holders in spillable accounts carried risk all year. In practice, with Eildon in the mid-40s, spill risk was negligible.

New South Wales

NSW Murray General Security allocations finished at just 10% — they doubled from 5% mid-season on improved inflows, lower evaporation and reduced delivery losses. Account balances, propped up by carryover, averaged about 45% of entitlement (roughly 754 GL). High Security fared far better. NSW allocations are more volatile than Victoria's — General Security can open at 0% in dry years.

South Australia

SA received its full allocation under the Murray-Darling Basin Agreement. SA Murray allocation prices traded at a downstream premium — $186/ML in WY2024/25 versus Zone 1A at $104/ML.

Storage levels — the critical numbers

Storage	Approx. %	Volume (approx. ML)	vs Last Year	Trend
Lake Eildon	46%	1,530,000	~10pp lower	Falling slowly
Waranga Basin	47%	203,000	Lower	Falling
Dartmouth Dam	65%	2,505,000	Lower	Stable
Hume Dam	23%	690,000	Lower	Bottoming
Lake Eppalock (Zone 2)	37%	113,000	Lower	Stable

The headline: GMW's regional storages are tracking roughly 9-10 percentage points below this time last year, and Eildon is on course to enter WY2026/27 (1 July) in the mid-40s. That is the tightest winter starting position since the drought years, though not yet at the WY2019/20 extreme.

Hume at about 23% is critically low, though Dartmouth (65%) provides backstop capacity. The Murray system will draw on Dartmouth to maintain Zone 6 allocations — this buffer keeps Murray HRWS above Goulburn HRWS in early season.

IVT status

The Goulburn-to-Murray IVT corridor is now in the post-15 December period — only back-trades create new opportunity. The effective season for forward IVT is closed.

For WY2026/27 planning: the first IVT tranche reopens on 1 July. Given the tight storage outlook, expect strong demand for Goulburn-to-Murray transfers early in the season. If the opening allocation is low and Murray irrigators scramble for Goulburn supply, IVT could come under pressure earlier than usual.

Weather and seasonal outlook

BOM's latest indicators:

• ENSO: Neutral-to-developing El Nino — model probabilities of an event rise sharply through winter
• IOD: Neutral through autumn (the IOD is climatologically inactive December-April); models increasingly favour a positive IOD developing in winter-spring
• Rainfall outlook (May-July): Below-average likely for southern MDB catchments
• Temperature outlook: Above average

This combination — a developing El Nino, the odds shifting toward a positive IOD, and a below-average rainfall outlook — is the bullish setup for water prices. If El Nino fully confirms by August-September 2026, winter/spring inflows will be below average and Eildon will struggle to recover. The last time these conditions aligned was WY2018/19.

What this means for WY2026/27

Price outlook

Scenario	Conditions	Zone 1A VWAP projection
Bull case	El Nino confirms + positive IOD develops	$400-500/ML
Central case	Neutral-dry, Eildon opens in the mid-40s	$300-380/ML
Bear case	Surprise wet winter and spring	$150-220/ML

Base case: Eildon enters in the mid-40s, opening HRWS at 30-40%, prices opening near current late-season levels ($300-340/ML) and peaking at $380-450/ML in January-February 2027.

If you need to buy next season

Start planning now. The early-season window (July-September) typically offers lower prices than mid-season. In a year where opening allocations will be low, locking in 50-60% of your requirement early gives you cost certainty before the market runs.

If you hold entitlements with carryover capacity, carrying any surplus from WY2025/26 gives you a head start on 1 July without touching the temporary market.

If you have surplus to sell

Late-season selling into May-June faces the June 30 cliff — holders dumping water before expiry. If you have surplus, consider:

• Selling now at current levels rather than waiting for a thinning market
• Carrying over if you have headroom (spill risk is negligible at current storage levels)
• Carrying over is essentially a bet that WY2026/27 prices will exceed current levels — given the outlook, that bet looks favourable

Carryover deadline reminder

Victorian carryover is automatic — unused allocation in your account at 30 June rolls into WY2026/27 as spillable water, up to 100% of your water share volume. The real deadline is the hold-versus-sell decision: once 30 June passes, you are committed to next season's spill risk and prices.

Given Eildon in the mid-40s and the dry outlook, carrying into WY2026/27 is strongly favoured. Spill risk is negligible.

Entitlement market

Permanent HRWS entitlement activity has increased this month. With the dry outlook strengthening, entitlement values are likely to firm. Historical pattern: entitlement prices lag allocation price rises by 3-6 months. The time to buy entitlements cheaply was WY2022/23 at $2,000-2,500/ML. Current levels are likely $3,000-4,000/ML and rising.

Frequently asked questions

Where does the price data come from?

VWR (Victorian Water Register) published trade data for Zone 1A and Zone 6. Ricardo Water Markets Reports for multi-zone coverage (Zone 7, NSW, SA). Our own brokerage activity supplements this with real-time visibility.

How often are allocation announcements made?

NVRM announces fortnightly during the irrigation season (approximately July-March). The first seasonal determination is published on 1 July.

What does IVT closure mean for me?

If Goulburn-to-Murray IVT is exhausted, Zone 1A water cannot transfer to the Murray system. Murray buyers lose access to Goulburn supply. Zone 1A prices may soften while Murray prices firm. Plan cross-zone purchases before IVT runs out.

How do storage levels affect prices?

Eildon's percentage full on 1 July is the best single predictor of the season's allocation price. Below 40% = expect $350+/ML. Above 80% = expect $50-120/ML. Monitor weekly at the GMW or BOM water storage dashboards.

Can I subscribe to these updates?

Yes. Contact us to join our monthly market update mailing list during the irrigation season.

Looking ahead

Key dates for WY2026/27:

• May-June 2026: Watch winter rain. Does Eildon recover?
• 1 July 2026: Season opens. First NVRM determination. Opening HRWS below 40% is bullish.
• August-October: BOM September outlook. Below-average for spring = buy signal.
• 15 October: Second Goulburn-to-Murray IVT tranche opens.
• November-January: Peak demand. Price apex.

The June 2026 update is now available, covering final WY2025/26 numbers, carryover decisions and the setup into the new season.

Disclaimer: This market update is general information only. It does not constitute financial, investment, or water trading advice. Water prices are subject to seasonal conditions, government policy, and factors beyond anyone's control. Past prices are not a reliable indicator of future prices. Seek independent professional advice before making trading decisions.

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