The Olympos Centre at Burgess Hill (previously known as Triangle Leisure Centre) was opened in March 1999 by Mid Sussex District Council. The Centre, which receives an average of 1000 bathers per day, boasts an 8-lane, 25m indoor competition pool, a separate leisure pool with indoor and outdoor rapids, splash pool, toddler's pool, spa pool and two flumes.
Challenge
Mid Sussex District Council chose to install medium-pressure UV disinfection units from a proprietary UV manufacturer when the pools were originally built, however they were not completely satisfied with the results. After noticing a deterioration in the water quality due to increasing combined chlorine levels, they decided to contact Evoqua Water Technologies for a solution.
Solution
After an initial assessment, the decision was taken to install Evoqua Barrier® M medium-pressure UV units. Ultraviolet technology is proven to deliver fast, reliable, effective, economical, and environmentally-friendly disinfection, effective for the removal of odorous and potentially harmful chloramines in swimming pools.
Medium-pressure UV is considered to be particularly effective at chloramine reduction. Barrier M UV units have a unique energy reducing and compact space-saving design, combined with an increased lamp life from 4000 hours to 9000 hours over the original UV package. Other benefits include competitive capital and spares price packages and a significant reduction in water consumption.
Results
Prior to the Evoqua installation, the combined chlorine levels at the Olympos leisure pool had peaked at 2.4mg/l. When the two Barrier® M UV units were switched on in September 2005, the chlorine set points were lowered to 1mg/l. Within 72 hours the combined chlorine in both pools had fallen to below 0.2mg/l, with the UV output, set by the disinfection control, programmed at the lowest of the four settings.
Twelve months after the Barrier M UV units were installed, The Olympus Centre also took delivery of a Evoqua DEPOLOX® Pool system. In addition to being to able to monitor the parameters of free chlorine and pH-value, the DEPOLOX Pool system goes one step further and offers sensors for total chlorine, Redox, conductivity and temperature, all combined in one single unit.
The total and free chlorine sensors are used to measure the combined chlorine levels in the pool and increase the UV dose during periods of sustained high pollution input, thereby optimizing the energy input required to maintain ideal bathing conditions.
This is a key benefit for Olympos as they can receive up to 12,000 bathers on an average bank holiday weekend. The DEPOLOX Pool system provides a digital output signal to the circulation pump inverter drives to reduce the circulation rates of the pools during periods when ideal water quality conditions allow for a lower turnover rate (e.g. overnight). This delivers cost-savings without jeopardizing the pool water quality.