Share of prefectural governments' civil engineering expense Japan FY 2021, by purpose
In the fiscal year 2021, close to 44 percent of the total budget for civil engineering work of prefectural governments in Japan was utilized for constructing roads and bridges. The total value of expenditures of prefectural governments on civil engineering work during the measured time period amounted to over 6.3 trillion yen.
The majority of the roads in Japan are made of asphalt. In order to reduce the heat from the "urban heat island" phenomenon, the Japanese governments, especially the Tokyo metropolitan government, are promoting the water retentive pavement and heat insulation paving of asphalt.
