Brisbane City Mud Springs

This is a rare geological formation or which there are only possibly two in Australia. Although the formation always existed, in 1946 they started to grow rapidly larger until, there were five mounds 3 metres high. In 1970 a bore was sunk to 360 metres to look for natural gas. Further tests showed there was a substantial amount of methane gas at 1300 metres The mud goes down to 30 metres. A stream of water runs from a sub artesian basin behind Bald Hills. The water hit a clay capping which is over a dome of gas. In 1970 the Brisbane City Council moved the mounds when it excavated to lay a large water main across Graham Road. As a consequence of the excavation a huge amount of mud started to surge up from a hole accompanied by a dreadful smell of hydrogen sulphide gas. Hawbridge Street was isolated for eight weeks while the Council carted away truckloads of mud. The land around it then sank. Sheet pilings were dumped on the mud to form a caisson, the pipes dragged through and 12 truckloads of concrete were placed over the pipes to hold them down. The crust is only 15 cm thick. It is advisable not to enter the fenced off area.
Information supplied by Joe Spina, 1997 (History wording sign).