plumbingdrainageengineeringequipment
What is the difference between a balance tank and a surge tank?
Quick answer
A surge tank stores water that has run off the pad, returning it to the recirc loop. A balance tank handles water-level fluctuations between the pad surface and the equalizing line. Many splash pads combine both into one buffer tank. Sized at 1.5-3x the active pad water volume.
Surge tanks and balance tanks serve related but distinct functions in recirculating splash pad systems. The surge tank receives runoff water from the pad surface drains, settles out heavy debris, and stores water for the recirc pump. The balance tank handles water-level fluctuations caused by the pad surface filling and emptying as features cycle, preventing pump cavitation and overflow conditions. Many smaller splash pads combine both functions into a single buffer tank sized at 1.5-3 times the active pad water volume — large enough to absorb a full pad of water without overflowing. Larger or more complex pads use separate tanks connected by an equalizing line. Both tanks need access hatches for cleaning, level sensors with high and low alarms, overflow weirs to sanitary sewer, and bottom drains for purging. Maintenance requirements (annual purge, inspection) are identical for both tank types.