Likely minimal flow; likely too low for any reasonable whitewater experience.
The section name fibs just a little when it says "Whitaker Avenue" -- that is the turn-off from S.27th Street.
Follow Whitaker east (to its end), then turn onto a short dead-end stub of W.Bottsford Avenue.
Park in that stub and carry down among the scrub/shrubbery to the creek.
Look downstream before you put on to ensure passage is clear through this brief narrow tree-lined area before the cement ditch begins!