part of visceral mass water vascular system BTO:0002125 BrendaTissueOBO The water vascular system is a hydraulic system used by Echinoderms for locomotion, food and waste transportation, and respiration. Composed of water filled tube feet and ampulla, Echinoderms move by contracting the muscles around the ampulla forcing water in the tube feet, which causes the foot to extend propelling the animal forward.