 The state of Eyre Highway remained relatively unchanged throughout the 1940s and 1950s . The road received yearly maintenance , but further , more expensive works were not warranted due to the low traffic volume of approximately fourteen vehicles per day . However , the maintenance and grading was hindered by a lack of rainfall – the road was smoothed out each year , and small sections were gravelled , but the soil the road was made from was too weak to be an effective road surface . When it did rain , even in small amounts , the road would become boggy , from patches that had broken down into a powdery substance ( known as " <unk> " ) during dry periods . Large numbers of vehicles travelling the highway in 1962 , for the Commonwealth Games in Perth , damaged the road in numerous locations , and the lack of moisture required salt water to be pumped from 350 feet ( 110 m ) below the surface for use in repairs and maintenance . 
