Actuator suppliers for Sequencing Batch Reactor (SBR) decant weir applications are often challenged by consistently high mechanical loads. These demands can be met by tailor-made, modular Auma actuation solutions with high torque range and equally high safety performance levels. Auma reports that the duty cycle of weirs is such that the actuator is required to perform 6000 revolutions per day. As a result, actuators need to provide consistently high performance standards for just under six million revolutions per annum. Results from tests conducted by De Vos Chater and Associates of Perth showed that a typical weir experiences substantial positive and negative load reversals during every stroke which require as much as 900Nm of torque. Meeting the exacting demands of SBR decant weir operation, Auma’s actuation solution includes GK bevel gearboxes with actuators/gearboxes equipped with high corrosion protection if required. WwTWs equipped with Auma SBR decant technology include nine Australian sites. Listed among the utilities that use Auma’s actuation solution is SA Water’s Bolivar Environment Improvement Program: the scheme contains twelve weirs and provides treated wastewater suitable for direct irrigation.