The hydrodynamic mechanisms which subserve the outflow of newly created outflow canals in sclerostomy procedures are to a large extent obscure. The model presented here has strong analogies to a closed electric circuit and assumes that aqueous humor is pumped by the secretion pump into the anterior chamber, leaves the eye via the artificially created sclerostomy canal, and returns via the venous and arterial system to the ciliary body. The model attempts to describe the stationary situation which determines the intraocular pressure following sclerostomy in terms of the internal resistance of the secretion pump, the resistance in the sclerostomy canal, the resistance beyond the external ostium of the sclerostomy canal, the pressure in the anterior chamber, the pressure beyond the external ostium of the canal, and the secretion pressure exerted by the secretion pump.