A ONE-in-2000 year rainfall event earlier this year saw Lake Awoonga near Gladstone reach 193% of its capacity after record water inflows associated with ex-tropical cyclone Oswald.

That was one of the key points outlined in the Gladstone Area Water Board annual report which was tabled in State Parliament on Monday.

In the report, Gladstone Area Water Board chairwoman Mary Boydell said water levels at the Lake Awoonga spillway started overflowing on January 25 and continued until early May.

"Gladstone Area Water Board managed the spill event in accordance with its emergency action plan," she said.

"We were in continuous contact with the local disaster management group throughout the event, providing advice about modelling and consequences, and were also in close contact with the dam safety regulator.

"The dam infrastructure performed in accordance with design specifications, although the auxiliary spillway at Saddle Dam 3 and other infrastructure at Awoonga Dam will require some remediation work.

"This work will be completed before the next wet season."