Question

Where does surface water collect if it does not flow to the ocean

Answer 1

Multiple reasons...
It could get absorbed into the soil.
It may be absorbed by plants.
It might go through permeable rock and into a groundwater store. 
It could also evaporate. 
It could, instead of flowing into the ocean, flow into another water store such as a lake or pond. 
If it is a large amount of water, humans might dam the area to collect and store the water for long term use. 

Hope these answers are alright.