He was pragmatic in office, tackling many chronic problems in Istanbul including water shortage, pollution and traffic chaos. The water shortage problem was solved with the laying of hundreds of kilometers of new pipelines. The garbage problem was solved with the establishment of state-of-the-art recycling facilities. While Erdoğan was in office, air pollution was reduced through a plan developed to switch to natural gas. He changed the public buses to environmentally friendly ones. The city's traffic and transportation jams were reduced with more than fifty bridges, viaducts, and highways built. He took precautions to prevent corruption, using measures to ensure that municipal funds were used prudently. He paid back a major portion of Istanbul Metropolitan Municipality's two billion dollar debt and invested four billion dollars in the city.