Safe digging practices for backyard excavation in Hawthorn – avoiding power lines & water pipes?

Hey everyone, hoping to get some practical safety advice for an upcoming backyard project in Hawthorn. We're planning to dig deep trenches for a new garden drainage system and install heavy fence posts along our boundary. However, our property has multiple underground services including hot water supply lines, electrical cables, and irrigation feeds running through the yard at various depths. I've been reading through https://leaksrus.com.au/avoid-damaging-underground-pipes/ which breaks down how buried lines can sit anywhere from a few inches to 48 inches deep, and I'm terrified of an excavator bucket hitting a hot water pipe or live electrical conduit and causing a dangerous or super expensive disaster. Is there a reliable team for water leak detection melbourne and private utility scanning that can accurately locate and map all these underground assets before we start digging?