Greater Sydney’s dams are 93.3% full (2,344 GL of 2,511 GL), down 0.4 points in a week; a year ago the same storages were 99.8% full.
15 storages reporting to the Bureau of Meteorology, latest reading 2026-09-27 23:00. Refreshed every 30 minutes.
Here are the fifteen storages that the Bureau of Meteorology groups as Sydney’s supply system, from Warragamba and the Upper Nepean dams to the Shoalhaven reservoirs and the small Blue Mountains dams, each with its latest volume, percentage, level and weekly movement. Under the table you will find how WaterNSW arrives at its Greater Sydney percentage, what Warragamba holds and how it is run in a flood, and which of these waters are open to anglers.
Percentage full is the Bureau’s accessible volume divided by the accessible capacity, as on its storage dashboard, so it can differ by a point or two from the operator’s daily report, which is the official figure. Year ago is the same storage on the same date last year. Dams with a fishing page link to it.
| Storage | Full | Volume (ML) | Capacity (ML) | 7 days | Year ago | Updated | Fishing |
|---|---|---|---|---|---|---|---|
| Warragamba DamGreater Sydney water supply (WaterNSW) | 95.3% | 1,931,633 | 2,027,000 | −0.3 pts | 99.9% | 27 Sept | No public fishing |
| Cataract DamGreater Sydney water supply (WaterNSW) | 76.7% | 74,569 | 97,190 | −1.0 pts | 99.2% | 26 Sept | No public fishing |
| Cordeaux DamGreater Sydney water supply (WaterNSW) | 76.5% | 71,645 | 93,640 | −0.4 pts | 99.6% | 27 Sept | No public fishing |
| Tallowa DamGreater Sydney water supply (WaterNSW) | 98.8% | 82,686 | 83,690 | −1.0 pts | 101.3% | 27 Sept | Tallowa Dam fishing report |
| Woronora DamGreater Sydney water supply (WaterNSW) | 91.7% | 65,809 | 71,790 | −0.2 pts | 101.0% | 27 Sept | No public fishing |
| Nepean DamGreater Sydney water supply (WaterNSW) | 74.8% | 50,662 | 67,730 | −1.1 pts | 97.2% | 27 Sept | No public fishing |
| Prospect ReservoirGreater Sydney water supply (WaterNSW) | 90.0% | 29,997 | 33,330 | −1.3 pts | 93.9% | 27 Sept | No public fishing |
| Wingecarribee ReservoirGreater Sydney water supply (WaterNSW) | 105.6% above capacity | 25,480 | 24,130 | −0.1 pts | 107.7% | 27 Sept | No public fishing |
| Fitzroy Falls ReservoirGreater Sydney water supply (WaterNSW) | 84.3% | 8,386 | 9,950 | +0.1 pts | 80.4% | 27 Sept | Fitzroy Falls Reservoir fishing report |
| Upper Cascade DamGreater Sydney water supply (WaterNSW) | 97.3% | 1,743 | 1,791 | +0.7 pts | 95.9% | 27 Sept | No public fishing |
| Medlow DamGreater Sydney water supply (WaterNSW) | 101.1% above capacity | 330 | 326 | +0.0 pts | 101.6% | 25 Sept | No public fishing |
| Lower Cascade DamGreater Sydney water supply (WaterNSW) | 92.3% | 281 | 305 | −7.7 pts | 96.8% | 27 Sept | No public fishing |
| Greaves Creek DamGreater Sydney water supply (WaterNSW) | 100.7% above capacity | 303 | 301 | +0.1 pts | 100.8% | 27 Sept | No public fishing |
| Middle Cascade DamGreater Sydney water supply (WaterNSW) | 96.7% | 162 | 167 | +4.7 pts | 100.3% | 27 Sept | No public fishing |
| Avon DamGreater Sydney water supply (WaterNSW) | — | 194,038 | — | — | — | 27 Sept | No public fishing |
Among storages of 5 GL or more.
90% and over60–90%30–60%under 30%no capacity published
Combined accessible volume of the 14 storages with a published capacity, as a percentage of their combined capacity, one value a day.
The Bureau of Meteorology groups fifteen storages into its Sydney supply system, and each one has a row in the table. Warragamba Dam sits in a narrow gorge on the Warragamba River, about 65 kilometres west of the city. South of Sydney, four dams were built on the Illawarra Plateau between 1902 and 1935: Cataract, Cordeaux, Avon and Nepean. Cataract and Cordeaux feed the Macarthur filtration plant for the Camden, Campbelltown and Wollondilly areas, Avon mainly serves the Illawarra, and together the four can send extra water to Sydney through Pheasants Nest Weir, Broughtons Pass Weir and the Upper Canal. Woronora Dam, finished in 1941, supplies Helensburgh, Engadine and parts of the Sutherland Shire and northern Wollongong. Further south, Tallowa Dam, Fitzroy Falls Reservoir and Wingecarribee Reservoir form the Shoalhaven Scheme, which WaterNSW describes as a back-up for the Sydney and Illawarra supplies. Prospect Reservoir and five small Blue Mountains dams, Greaves Creek, Medlow and the Upper, Middle and Lower Cascade dams, complete the list; the Bureau credits the five mountain dams with about 2,890 megalitres of accessible capacity between them.
WaterNSW’s Greater Sydney Dam Levels page opens with one number, the share of storage capacity in use, shown with its weekly change, the day’s water use and catchment rainfall, and it is updated daily. Ten storages sit behind that number: Warragamba, Avon, Cataract, Cordeaux, Nepean, Woronora, Prospect, Tallowa, Fitzroy Falls and Wingecarribee, each listed with a capacity and a current volume in megalitres. Adding up those volumes and dividing by the listed capacities reproduces the headline. Warragamba’s listed capacity of 2,064,680 megalitres is close to four-fifths of the ten-storage total, so the Greater Sydney figure rises and falls largely with it, and a sharp change at a small reservoir barely registers. The Blue Mountains dams are not on that list. The rainfall panel gives an area-weighted average for the whole Greater Sydney catchment plus separate totals for the Warragamba, Nepean, Woronora, Shoalhaven and Blue Mountains catchments, and WaterNSW notes that its rainfall figures change on weekdays only.
This table uses the Bureau’s accessible volume and accessible capacity for every storage, and the two organisations do not always count capacity the same way. WaterNSW lists Tallowa Dam at 7,500 megalitres, while the Bureau’s accessible capacity for Tallowa is 83,690 megalitres, so the two percentages for that dam can sit far apart on the same day. Wingecarribee is listed at 29,880 megalitres by WaterNSW and 24,130 by the Bureau, and Warragamba at 2,064,680 against the Bureau’s 2,027,000. At Avon Dam the Bureau’s volume currently runs above its own accessible capacity, so the Avon row gives a volume without a percentage. A total built from the Bureau’s figures also takes in the five Blue Mountains dams. When the Bureau adds up a region, it uses each storage’s latest reading if that reading is less than 30 days old, and if the storages without recent data hold more than 7 per cent of the region’s capacity, it keeps showing the last valid total instead of a partial one.
Warragamba Dam was built between 1948 and 1960 by about 2,000 workers on round-the-clock shifts, and a Workers’ Memorial in the grounds remembers the 14 who died during construction. Lake Burragorang, the water it holds back, stretches 52 kilometres from the wall and covers about 75 square kilometres, and WaterNSW gives the dam a capacity of 2,065 gigalitres. Sydney Water says about 80 per cent of Sydney’s drinking water comes from Warragamba and the rest from other dams, rivers and the ocean. It draws on 11 major dams through 13 delivery systems, and the privately owned Sydney Desalination Plant, able to supply up to 1.5 million people, becomes part of that network during drought. WaterNSW’s flood fact sheet describes Warragamba as the supply for more than 5 million people in Greater Sydney and the lower Blue Mountains. The proposal to raise the wall, Warragamba Dam Raising (SSI-8441), was meant to add temporary storage for large inflows so as to reduce flooding downstream; the NSW Planning Portal now lists it as withdrawn.
Under the rules that govern Greater Sydney’s dams, WaterNSW is not permitted to operate any of them for flood mitigation. Regional New South Wales is different: there WaterNSW can release water before forecast rain to make airspace, with targets set in consultation with community Airspace Reference Panels. During a flood, Warragamba’s gates are operated under the H14 operational protocol, with two objectives, the safety of the structure and ending the event with the lake back at full supply level. WaterNSW’s fact sheet explains that the big Hawkesbury-Nepean floods mostly come from East Coast Lows, that heavy rain in the Southern Highlands can take several days to reach the dam, and that the Grose, Colo and Upper Nepean add their own floodwater: in March 2021, water from Warragamba made up 60 per cent of the flood that reached Windsor. Avoiding that spill would have meant lowering the dam to about 60 per cent, roughly three years of Sydney’s supply. WaterNSW does not issue flood warnings; the Bureau does, the NSW SES leads the response, and WaterNSW’s WaterInsights portal and WaterLive app carry near real-time river and dam data.
The catchments of this system are declared Special Areas under the 2014 Water NSW Act: Blackheath, Katoomba and Woodford in the Blue Mountains, Warragamba, Prospect, the Metropolitan catchment, Woronora, Wingecarribee, Fitzroy Falls and the Shoalhaven. Under the Water NSW Regulation 2026, Schedule 1 land is closed to the public and Schedule 2 land allows entry on foot only; WaterNSW and the NSW National Parks and Wildlife Service manage them together, and fines reach A$22,000 for an individual. The picnic grounds at Warragamba, Avon, Cataract, Cordeaux, Nepean, Woronora and Wingecarribee all rule out fishing, boating and swimming. Angling in this system happens in the Shoalhaven Scheme. At Fitzroy Falls Reservoir, about 140 kilometres south of Sydney, WaterNSW allows fishing for trout and bass from designated spots on the eastern foreshore. Bendeela Recreation Area, on the Kangaroo River arm of Lake Yarrunga, offers camping, canoe launching and river fishing, with no motorised watercraft. Tallowa Dam itself is closed until mid-2027 for repairs to Tallowa Dam Road, with no vehicle access for launching or retrieving paddle craft there. The NSW Recreational Fishing Fee applies at every one of these waters, and WaterNSW posts blue-green algae alerts for parts of Lake Yarrunga and for Fitzroy Falls that are worth reading before a trip.
Find the Warragamba Dam row in the table: it shows the volume, the per cent full and the water level in metres above the Australian Height Datum from the latest reading the Bureau has received, which usually trails the calendar by a day or two. The percentage is worked out against the Bureau’s accessible capacity of 2,027,000 megalitres, a little below the 2,064,680 megalitres WaterNSW uses, so WaterNSW’s own Warragamba figure can differ slightly.
The table gives each of the fifteen storages in the Bureau’s Sydney system. For a single Greater Sydney percentage, WaterNSW’s dam levels page combines ten of them, and because Warragamba holds most of that capacity, its row is the quickest guide to where the total stands.
WaterNSW’s total covers ten storages and uses its own capacities, while the Bureau’s Sydney system adds the Blue Mountains dams and uses accessible capacities, which differ most at Tallowa Dam. Timing differs too: WaterNSW refreshes its page daily, and the Bureau publishes after its own checks.
A Warragamba reading above 100 per cent in the table means water above full supply level, passing over the spillway or out through the gates. For release and spill notices as they happen, register with WaterNSW’s Early Warning Network, and for flood warnings follow the Bureau of Meteorology and the NSW SES.
Only in the Shoalhaven part of the system: from the designated eastern-foreshore areas at Fitzroy Falls Reservoir, and on Lake Yarrunga from Bendeela Recreation Area. Warragamba, the four Upper Nepean dams, Woronora and Wingecarribee rule out fishing, and the remaining storages lie inside Special Areas.
Data: Bureau of Meteorology, Water Data Online and the Australian Water Storages dataset, © Commonwealth of Australia, CC BY; volumes supplied by © WaterNSW. Where the Bureau lists no capacity, or its capacity and volume are on different bases, a row shows the volume only. Text by Pablo Ruiz Quintero.
The facts on this page were checked against these pages, from the agencies, park services and operators that manage the water on 28 September 2026; anything we could not verify was taken out. Written by Pablo Ruiz Quintero. Errors are published in the verification log.