PNe often express multipolar, point symmetric shapes - while their progenitors are characterised as having spherical layered structures. As stars depart from the AGB asymptotic, they launch powerful jets that are believed to be responsible for creating the diverse shapes of PNe. Examples of collimated jets are those traced by water masers, in post-AGB objects named “Water Fountains" (WF), with jet speeds ~100 km/s and sizes ~1000 au. WFs are very rare due to their short timescales (~100 yr) and as such the launching mechanism of their collimated jets remains an unresolved puzzle. In this talk, we introduce our VLBI water maser observations of IRAS 18113-2503 showing a WF with spectacular bipolar bow-shocks in their high-speed collimated outflows. Through VLBA and VERA observations, we unveil the spatio-kinematical structure of the bipolar bow-shocks and the trigonometric distance to the source (12 kpc). Seen for the first time in WFs, the measured 3D maser velocities (>200 km/s) show that the jets are formed in very short-lived (tens of yr), episodic outbursts (period ~10-20 yr), which are intrinsically linked to the driving source (binary system?). We also note that these short-lived, episodic ejections observed in the WF mimic what we have also observed previously in protostars.