Best flow routing algorithm for determining location where spill enters stream?

What would be the best flow routing algorithm for determining the quickest (shortest) path that a spill would take when traveling to a stream?

My best educated guess would be that the D8 would provide the quickest path for a spill traveling from land to the stream. It minimizes dispersion (which would most likely slow the spill down) and maximizes velocity (ignoring surface friction due to different landcover types - if this can be ignored).

Does anyone have any experience with this?