Melbourne desalination stories can describe an order for a financial year, a delivery milestone or a cumulative production total. Each number answers a different question. Keep its period and the activity it measures attached to it before comparing figures.
Start with the dated order announcement. It tells you what supply was requested. Evidence of production or delivery needs a record of that activity, not just the size of the order.
An order is a future supply decision
Melbourne Water's 7 April 2026 announcement records an order of 150 billion litres for 2026-27. That confirms a supply decision for the named financial year; it does not establish that the whole volume has already entered storage.
The utility's desalination-data page gives the plant's capacity as up to 150 billion litres a year. A capacity rate and an order can have the same number while describing different things. Capacity describes how much the plant can produce over a year; the order names requested supply for a particular year.
When sharing an order figure, keep the word order in the sentence. Replacing it with delivered changes the claim.
Follow the delivery period
The 4 April 2025 announcement records a 50 gigalitre order for the following financial year. A Victorian Government delivery update, last updated on 21 August 2025, says the first 10 billion litres had reached drinking-water storages, with delivery beginning in July.
That is a progress statement for the earlier order. It should not be presented as the delivery achieved against the later 2026-27 order. Keep the announcement date and the delivery update together so the sequence remains visible.
Check the units before comparing figures. Gigalitres and billion litres are equivalent, but an order, a milestone and an annual capacity still describe different activities. Before doing arithmetic, identify whether the record concerns requested volume or water actually produced or delivered.
Water enters a connected supply system
Melbourne Water's 21 April 2026 account of the water's journey describes treated desalinated water reaching Cardinia Reservoir and mixing with water from natural catchments. It associates Cardinia with southern and eastern Melbourne and the Mornington Peninsula.
That describes a connection into a supply system. It provides no current desalinated-water percentage at a particular address. A regional delivery total cannot be used to label every glass across Melbourne as having the same source mix.
For an accommodation question, use the address with the relevant water supplier. A reservoir connection is background to that inquiry, not an individual source-share result.
Keep production totals separate from today's tap
The desalination-data page states that, following completion of the 2025-26 order, the plant had produced 505 gigalitres since 2017. That is a cumulative production statement. The page does not give an exact cutoff date for that total.
It cannot establish how much of the later order has been delivered today. A later progress question needs dated production or transfer evidence for the correct period. The Melbourne city guide offers general visitor guidance; desalination planning figures do not replace local water-quality results or notices.
