I want to know which scenario is more efficient and more economic in surface runoff management in an urban region which is highly dependent on water resources.
your question is so general! from which viewpoint you meant surface runoff managment in an urban area. Generally, surface runoff management differs from other catchment managemnets in a way that you deal ith catchments which thier most areas are imprevious, so the time of concentration as well as the amount of runoff would be considerably high! Nevertheless, we would make some decisions to control surface runoff at its source, through LID, BMP.
Kindly be more explicit and tell what do you exactly need and mean. Thanks.