In the 27 years since the foundation of Shenzhen, an urban infrastructure of streets, lighting, sewage, environmental care, drainage and transport has been developed in Shenzhen. The city government strives to improve its management of the infrastructure network. The city’s construction area totals 719.88 square kilometers. In 2006, the city’s investment in urban infrastructure reached 40.784 billion yuan, up 23.9 percent over the previous year. Tap water is now available for use in all households in the city.