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Gibraltar’s wastewater system has provided a unique challenge for pump companies. P&M Pumps the UK distributor for Vaughan Chopper Pumps, and Aquagib, the company appointed by the Government of Gibraltar, took on that challenge. They worked together to provide a long term solution, but for several years there was a need for significant maintenance and repair resulting from pumps not coping with heavy rag, and solids entering the wastewater system.
Unique challenge
The problems Aquagib were experiencing were mainly due to the necessity to avoid using submersible pumps because of salt water corrosion. This was primarily due to pumping stations on Gibraltar utilising the sea water available to them for all of their waste water flushing systems including domestic flushing and in the pumping stations. Initially the answer to the problem was for the pumping stations to utilise a priming system involving a concept developed originally for filling steam engine water tenders with clean water. When used with an open-channel impeller centrifugal pump these systems operated to specification. However, as a result of significant changes in the nature of the solids (being less degradeable) the pumps became increasingly less reliable and prone to blockages within the priming system, causing the pumps and components to fail prematurely.
Combined with difficulties in obtaining critical spare parts for the pumps, which are now obsolete, the cost of maintaining the pumping stations in Gibraltar was unacceptable. Aquagib’s search for a solution was answered with the help of a Vaughan SP6K chopper pump, which was supplied initially on a trial basis at the Waterport Pumping station. Situated adjacent to the prestigious Ocean Village complex and one of Gibraltar’s high profile pumping stations, the Waterport Pumping facility is on an area of reclaimed land which includes several high value apartment developments overlooking a marina, restaurants, bars and other leisure facilities. The Waterport Pumping facility is on the important pedestrian route from the busy cruise liner terminal into Gibraltar town. Consequently, the frequent pump breakdowns resulted in high maintenance costs, noise and odour pollution in the local community and potential health risks, in an area that was particularly sensitive.
Smooth running
Following the successful trial of the pump, a standard Vaughan self-priming chopper pump was installed at the Waterport pumping station in October 2007 and has run consistently well with only routine maintenance required. Due to this consistently reliable operation, Aquagib have installed a second pump at the Waterport site. Furthermore, another seven Vaughan Chopper Pumps have since been installed in other pumping stations in Gibraltar. There are plans to replace others in the future and utilise them in the new pumping stations being planned.
Conclusion
Commenting on the success of the pumps, Derek Cano, operations director of Aquagib said: “Vaughan pumps have solved an on-going difficulty we have had for many years in dealing with pump blockages, they work effectively in unscreened sewage with a high sea water content”. He added: “P&M Pumps has provided excellent support which has enabled us to install and operate the pumps effectively”.
Through their experiences at numerous installations, P&M Pumps have been able to demonstrate that Vaughan Chopper Pumps can bring significant cost-savings. In most cases, retrofitting a Vaughan Chopper Pump into a problematic area improves the whole process and will be self-financing, with payback periods of less than one year, thereafter minimising the effect to the budget holders.
