Non-functioning Footpath

When a footpath cannot be used for walking, it is considered to be a faulty design. What happens to this footpath? 
The weep holes in the 1m high retaining wall discharge rain water onto the footpath. The footpath has no drainage discharge and level is lower near to the wall, so water accumulates there. In tropical climate, the moment water accumulates, algae flourish, making the floor slippery besides wetness. Nobody wants to walk on this kind of footpath.

One of the solutions is to provide drains near the retaining wall to drain the water away from the main footpath, a shallow one is sufficient. This drain shall connect to a discharge outlet such as manhole or to the drain beneath the footpath through uPVC pipe.

The other solution is to re-surface the floor such that it slants gently (say 1:200) towards the grass verge. As long as the water can flow away immediately and not stagnant, the floor will be walkable.