A debris removal tool uses a screen to separate the debris coming into the tool from the moving fluid. The fluid that gets through the screen then operates a flow sensing device that is preferably a turbine whose speed of rotation or other characteristics of its movement generates a signal that is picked up by the measurement while drilling tool and conveyed to the surface. The surface personnel first respond by turning off surface pumps to allow debris to fall by gravity off the clogged screen. If that fails, the tool is pulled through the well fluid inducing a reverse flow through the screen to get the debris blocking it to go back into the well through the debris removal tool inlet.
