Up to 150 first responders have descended on Lake Illawarra, but this time, no one is in danger.
State Emergency Service crews from the South Eastern region, covering Wollongong to Eden and inland as far as Yass and Cooma will be conducting training exercises on Lake Illawarra as part of Exercise Noah.
Joining them will be teams from NSW Fire and Rescue, Marine Rescue, NSW Ambulance and Surf Life Saving NSW.
Following a safety briefing, teams hit the water from Berkeley boat ramp just after 10am.
Over two days the teams will conduct exercises simulating flood rescues, including rescuing a dummy, as well as a nighttime exercise where teams will have to retrieve glow sticks that mark letters to form a word.
SES community capability officer Adam James said with teams normally dispersed over such a large distance, weekends such as this provided the opportunity to work together.
"We don't come across each other a lot, this gives us the chance to train together," he said.
The exercises will be coordinated from the mobile incident control centre, a custom built command centre about the size of a shipping container that expands to accommodate up to 12 operational support members.
The control centre can run on its own power and has been transported to remote areas where its self-contained internet and communications equipment support rescue crews in off-grid locations.
The exercises are based on a variety of scenarios, all of which are grounded in real-life responses that emergency crews have conducted in the Illawarra and elsewhere.
SES zone commander Tom Jory said the last time an exercise of this scale had been conducted was a decade ago in Bermagui, and while the teams were training for serious situations, the weekend was being run with a "spirit of fun" and to a more relaxed time frame.
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