Monthly Water Update

Rainfall was higher-than-average across 78 per cent of the area, predominantly in the northern half of the region, as well as the southeast, central west, and southwest. Less than one per cent of the area experienced its highest rainfall on record since 1900 for May. Average rainfall was observed across 19 per cent of the area, predominantly in the south and southwest of the region. Only three per cent of the area, predominantly along the southern border of the region, recorded lower-than-average rainfall, including one per cent of the area experiencing very-much-below-average rainfall. Total rainfall was 70mm, 100 per cent higher than the long-term mean of 35mm for May. Rainfall was the eighth highest for May in the past 123 years.

Streamflows were higher-than-average for 67 of the 80 sites with suitable data, including 49 sites experiencing very-much-above-average streamflow conditions for May. At six sites, streamflows were highest on record since 1980 for May. Average streamflow conditions were observed at 12 sites with suitable data. Only one site recorded below-average streamflows for May.

Median streamflow salinity (electrical conductivity) varied between sites from 34 to 6204 μS/cm. Of the 64 sites with suitable data, streamflows were of high-quality for 46 sites, fresh for ten sites, brackish for six sites, moderately saline for one site, and saline for one site. Burra Creek at Worlds End (Low Flow) had the highest salinity of all reporting sites, due to discharge from unconfined aquifers.

During May, storage volumes increased in seven systems, decreased in two systems, and remained stable in nine systems. By the end of the month, the volume of water stored was 89 per cent of the total accessible capacity, which is 32 percentage points higher than the previous year.