<p>A side access tank facility is provided. The side access tank facility comprises an enclosure for containing water therein. The enclosure has an opening disposed in a side wall thereof. A cover covers the opening in a water sealing engagement with the enclosure. The side access tank facility further comprises an in-tank equipment holding structure for holding in-tank equipment at a predetermined position inside the enclosure. A moving mechanism is provided for moving the in-tank equipment holding structure between a position inside the enclosure and a position outside the enclosure.</p>