In the middle of December 2018, the water level of Super-Kamiokande reached 37.5 meters— nearly full. After final work at the top of the detector, filling resumed. On January 29, 2019, when the water level was full and the covers of the tank were closed, Super-Kamiokande data taking restarted.
Professor Masayuki Nakahata, the spokesperson of Super-Kamiokande says “I am relieved that the upgrade work finished successfully and that observation has restarted with pure water. We plan to dissolve gadolinium in the tank around the end of this year or the beginning of next year in order to enter a new phase of observation”.