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 "bulldust") 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 below the surface for use in repairs and maintenance. Work to seal Eyre Highway was undertaken in the 1960s and 1970s. As the federal government refused requests from Western Australia and South Australia for a special allocation to fund the sealed road, the work was left for the states to finance, over a number of years. Construction began in 1960, at the Norseman end. By the end of that year had been reconstructed, and was ready to be sealed over a width. were sealed in 1961, another were completed by 1963, and in 1964 the seal reached out from Norseman. By the mid-1960s, approximately were being sealed each year. With increased priority given to the project from 1966, Western Australia's portion of the highway was completed in 1969, with a ceremony held in Eucla on 17 October. In South Australia, a decade-long program to seal the highway began in the mid-1960s. The first section to be completed was the route between Port Augusta and Ceduna, in December 1967. In October 1972 the Ceduna to Penong seal was completed, and the final link to be sealed, between Penong and the state border, was completed with a ceremony held on 29 September 1976 near Wigunda Tank, South Australia. Between Yalata and the state border, the highway was realigned and deviated considerably from the original unsealed route. In deciding the new alignment for the South Australian section of the highway between Yalata and the state border, long, straight, flat sections were purposely avoided to prevent driver boredom and consequent fatigue, as well as sun-glare and glare from oncoming headlights. The new alignment also took into consideration the potential tourism opportunities provided along the coast of the Great Australian Bight. The older route, Old Eyre Highway, runs