Watering from underneath can save on watering costs; approximately 30% of water used in an overhead spraying system does not make it to the riding surface. Also, water application should be more uniform than an overhead system, leading to a more uniform riding surface. Finally, particularly for an indoor arena, in an overhead system the spray can wet side walls leading to rotting of wood, corrosion of metal, and mold growth – this does not happen if the water is supplied from underneath.
Traditional ebb/flow systems were of the 'flooded' type, where a large reservoir of water sits on a water-tight membrane at the base. Some have plastic modules at the base to distribute the water upwards into the footing. One disadvantage is that the constantly flooded base tends to promote bacterial growth, leading to discoloration of the footing, malodour, and slime, which coats the base components and can block pipes. Another disadvantage is that if the lower impermeable membrane should leak, then the system continually fills with water, leaving the owner with an expensive water bill. Because of its complexity, a third disadvantage is that the systems are expensive.