I was reading the topic about how painting buildings white reduces the temperature and then I wanted to find out about the roads and pavements as well, so I googled and found this: Research paper
It is about changing the albedo of a surface, which is the amount of light it absorbs and that affects the amount of heat it absorbs and stores and how much it heats the air, and it can make a big change. You do need to plan where to change it carefully though, otherwise it just reflects more heat into buildings around and they use more energy for cooling.
Changing some of the surfaces in US cities, because the research is from the US - MIT, can lower the temperature by 2.5 - 2.7 degrees.
It's amazing how simple some environment solutions can be, like just changing the colour of walls and roads.