The Warragamba Dam, Sydney: At 94.1% - May Reach Full Capacity By Midnight and Spill Throughout the Week, Officials Say

The Warragamba Dam has reached the 94.1% level as of 5pm today, March 1, 2012 according to the report of The Sydney Catchment Authority (SCA). With continuous rainfall, the Warragamba Dam may reach its full capacity and begin spilling throughout the week. Current inflows to Warragamba Dam are at 130,000 megalitres per day.

According to the same report, "Warragamba Dam was built for water supply, not flood mitigation" this simply means that there won't be any spilling unless the dam is full.

SCA Acting Chief Executive Sarah Dinning released a statement yesterday, February 29th about conducting a pre-flood gate test at the Warragamba Dam today since it is likely to fill in the coming days for the first time since August 1998.

"As part of our standard flood preparations there are a number of actions taking place at the dam to prepare for the expected large inflows.

"This includes checking of our plant and equipment, ensuring pumps can operate under flood conditions and placing generators on standby.

"Importantly as part of these preparations the SCA will conduct a test of the flood gates on the dam to ensure they operate automatically to release water down the spillway when the dam is full.

"During the test, the gates will be manually opened for around 10 minutes to confirm they are working as expected, which will result in a slight discharge of water. This occurs when the dam rises to one metre below full storage," Ms Dinning explained.

"At this stage, we plan to test the gates tomorrow morning between 8am and 10am. However due to the variable weather conditions, we have staff available around the clock and the test will occur as soon as the dam reaches one metre below full storage.

"Once the test is completed, the gates will be closed and switched back to automatic mode."

It is important to note that during a flood, the gates on the dam will operate automatically to release water down the spillway.

"This protects the safety and integrity of the dam by preventing water going over the top of the dam wall.

"Once Warragamba Dam is 80mm above its full storage level the drum gate opens automatically.

"If the water level rises to 230mm above full storage level, the four radial gates on either side of the drum gate also open.

"Water released through the gates flows down the spillway into a pond more than 100 metres below.

Ms Dinning said the SES was responsible for flood management downstream of the dam.

"The SCA provides information on dam levels and discharges to the Bureau of Meteorology and the SES.

"The SCA will continue to monitor rainfall and inflows across the catchments in line with our normal operations and we will post information about the dam levels on our website" Ms Dinning concluded.

Residents in affected areas should follow the advice of the SES and in a flood emergency, contact their local unit on 132 500.

Key contacts are:

Visit the SES floodsafe website for information on flood preparedness

Visit Bureau of Meteorology (BOM) website for the latest forecast and flooding information

Visit NSW Roads and Maritime website for the latest on road closures or call 132 701