by Wade Stafford, Vice President, Wastewater Services
The life of a lift station is strenuous. Working to elevate wastewater is a daunting task on its own, but these systems must also operate within a highly corrosive environment, battle the presence of non-dispersible materials, and work continuously to maintain wastewater systems. Needless to say, these systems face tremendous amounts of strain from installation throughout their lifetime.
While common throughout the United States, the state of Florida has the highest concentration of lift stations in the country, with JEA’s wastewater system being comprised of over 1,300 pumping stations alone. These systems are commonly used in commercial and municipal sanitary sewer systems at the lowest point in a gravity pipeline to pump water from lower elevations to higher elevations so gravity can once again be the driving factor of movement in guiding the wastewater to water treatment facilities.
Despite their necessity and importance in our everyday lives at home, work, and businesses, lift stations rarely get recognized for their efforts. Often, their work is utilized but the system itself is left to follow the run-to-fail maintenance strategy, never serviced, or repaired until inevitable failure strikes.
Lift station capacity can range from 20 GPM to upwards of 100,000 GPM, with an average of 10,000 GPM. Transporting these massive amounts of corrosive wastewater every minute, lift stations must receive preventative maintenance and routine cleanings to minimize expected wear and tear and extend the system’s life. Neglect can lead to avoidable system failure, emergency services, and losses due to downtime.
Even further, proactive efforts beyond preventative maintenance can not only prevent unexpected expenses but bring in drastic costs savings. Site-specific wastewater system modifications can help property owners avoid failures via proactive reworkings and advancements in technology.
Lift stations utilized advanced electrical and plumbing technologies, that if properly maintained, can last upwards of 15 to 20 years. As with all technology, over two decades an array of innovations in the field can be made while technologies employed are worn due to usage. Proactively installing updated technology within systems can maximize the functionality and ROI of lift stations.
A life cycle cost analysis report performed by Xylem found that over a 15-year period, installing two new pumps within a lift station had a break-even time of fewer than four years and reduced overall costs by $53,000 . This was achieved by taking into consideration the geography, energy usage, and maintenance requirements for the installation’s location.
If a system has a history of repeated failure, retrofits should be considered. Retrofits are small-scale changes or redesigns in part of the system to install new capabilities that were not previously there. A common retrofit is the installation of sewage grinders at locations experiencing frequent and repeat clogging due to flushable wipes, rags, and other fibrous materials that damage pumps. These sewage grinders are not only capable but specifically designed to prevent clogging in high-risk lift stations by grinding collected materials into a fine slurry that can easily pass through lift station pumps.
The average cost of clogs for one lift station is estimated to reach $30,000 annually. One lift station grinder manufacture determined 4,000 retrofits of their grinder pumps have saved sewer agencies $120 million annually. After grinder installation, sites that once required de-clogging on a weekly basis no longer faced this challenge and the correlating repair costs.
Continual inspections and repair identification should be performed regularly. Replacing damaged pumps, valves, compromised pipes, electrical components, and frequent pumping of debris for removal from the wet well can prevent failures by being proactive in catching possible causes of failure before they occur. This mitigates expensive emergency services costs and prevents losses due to downtime.
One city with a population of 140,000 utilizes 70 municipal and 120 privately owned and maintained lift stations all working together to move and manage the city’s wastewater. If all these individual lift stations had installations, retrofits, and repairs to maximize efficiency, imagine the expansive cost savings that could occur in the city, let alone across the state and country.