I count 3 speedbumps on that road: Here, Here and Here. The first one is by a load of houses, so is presumably well lit. The second two are less well lit, so I guess the van came over one of those two.
The driver was presumably driving East (if not, they drove across the other side of the road to mount the pavement), so I'd guess the driver was about here when the van came over the speed bump - the last bump is around the corner, so probably wouldn't have dazzled the driver.
If that's the case (And I know there's lots of ifs and buts), then the driver and van were both heading along a straight road, yet the driver was surprised when the van went over the speed bump, so swerved onto the pavement, over the kerb?
The mind boggles.