Seepage holes can become clogged over time due to limescale build-up or overlying material and thus impair or even prevent the seepage function of the pipe. To restore the seepage effect, we have built a new type of structure for partial seepage hole cleaning. In this process, the blocked hole is blasted with a targeted water jet and at the same time even the overlying material (seepage packing, debris or foreign bodies) is loosened or removed.