Mark runs a very successful caf selling Malaysian food and has taken some time off work during the Christmas period to spend some time with his family. He has decided to visit a lake at his local National Park, which is a popular spot for water skiing, swimming and boating activities. The National Park is managed by the Marra Marra Council (hereafter Council).

There has been recent restoration works of the lake done by the Council which had to temporarily pause due to a labour shortage. As a result, parts of the lake were shallow while other parts were deep. Further, due to dredging done as part of the restoration works in the lake, there were rocks which had been displaced from the Deep Water section into other sections of the lake.

The Council had erected a sign next to the deep water section, indicating 'Lake restoration works in progress in this area. Displaced rocks. Visitors beware.'

Thomas, Mark's 16 year old son, an inexperienced water skier, upon reading the sign, was under the impression that the section of the lake in the far right hand corner, was not affected by displaced rocks. He believed this to be true especially since he did not see any signage in the far right hand corner of the lake where he intended to ski.

In fact, the water in the far right corner of the lake was also littered with displaced rocks due to strong water currents which had transported some of these displaced rocks further away from the sign into the far right hand corner of the lake. While skiing, his skis hit a large displaced rock causing him to lose his balance from his skis and suffer head injuries when his head hit a sharp rock in the water.

Meanwhile, Mark had decided to have a couple of alcoholic drinks before boating in the deep water section of the lake. The boats were hired from Boating Needs Pty Ltd (hereafter Boating Needs), a boating hire out service next to the lake. He decided to let loose after a long year and exceeded the usual safe boating speed limits marked on the signs around the lake. Visibility was poorer than usual. However, Mark was not keeping a good lookout and collided into another boat which had broken down a few days earlier and had been left to the side of the lake. Boating Needs had been advised previously of the near-miss accidents that other boats had with the broken-down boat in the past few weeks, especially when visibility was poor. Boating Needs however took no action to address this risk.

Advise using the IRAC format, as to the legal position of Mark and Thomas under the Tort of Negligence. In your answer, please discuss the elements as well as potential defences for each of them.