Take a look at a nice pack of 6 materials for Unity that will help you create wet roads inside the engine. The pack comes with tons of customizable parameters and features a cool road shader.
Want to create realistic roads in your game? This asset will help you.
6 different reflecting materials with the ability to adjust the puddles. 3 Layers of Wet Textures. You can adjust material parameters. Materials with Roughness map (reflection) and Normal map.
* Night Panorama not included.
Textures: 1024px-2048px
You can find more details here.