Additional to his Parliamentary Party responsibilities, McArdle assumed the role of Shadow Minister for Health in August 2008, until the LNP's emphatic victory in 2012. Following the party leadership change, McArdle remained in his position as Shadow Minister for Health. After the Liberal National Party's landslide win in the 2012 Queensland state election, McArdle was appointed as Minister for Energy and Water Supply by Premier Campbell Newman, overseeing long-awaited and modernising reforms in energy and water security, after a series of natural disasters and an historical drought.