A municipality is home to an aging wastewater lift station. Pumps are nearing the end their usefulness, the controls require modernization, and the access hatch should be replaced. Yet the concrete wet well remains solid and sturdy.
Do you think the station should be demolished and rebuilt? Not necessarily. The better question to consider is whether the existing infrastructure will support the pumping system of the latest standards, without compromising reliability and capacity.
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A well-designed pump station retrofit can preserve the infrastructure’s value while replacing parts that no longer meet operational standards.
Begin with the Structures that nobody wants to replace.
It’s expensive and difficult to repair the wet well due to its location in the ground, linked to pipes and essential for the collection of wastewater.
A concrete structure that is still usable could reduce the excavation and construction.
However, damage to the access hatch may complicate your decision. Romtec Utilities identifies wet well hatch replacement as a common retrofit requirement. Instead of affixing a hatch to deteriorated cement replacing the entire top layer can be a better option. This approach can be employed to increase access and improve the usability of the structure without needing to rebuild the whole wet well.
A More Powerful Pump Changes the Engineering
If a neighborhood in the area has seen a significant increase in population since the original lift station was installed. Existing pumps may not be able with the growing flow of wastewater.
A pumping station upgrade could involve higher-horsepower pumps, but equipment selection cannot happen independently of the surrounding system.
Engineers should also assess the system’s hydraulic requirements including the flow and head total dynamic. The installation of a bigger pump without considering the circumstances can cause more problems than it resolves. Making plans for future capacity at the time of initial design makes future expansion easy.
Make sure the wastewater is moving during Construction
A retrofit to a wastewater pump station presents a problem that normal project for replacement of equipment may not face: the station may require operation throughout construction.
Contractors are still working, and wastewater is still expected to arrive. According to the plan an interim bypass pumping system could be needed to keep service running while the existing equipment is taken down or new equipment is installed.
Romtec Utilities was able to address this kind of challenge at the Federal Law Enforcement Training Center in Brunswick, Georgia.
The project involved replacing two old wastewater lift stations, while operating the facility. The site-specific engineering packages, bypass pumping techniques allowed for the existing station footprints as well as operational needs. This case illustrates why it is important to take into consideration the sequence of construction before installing.
When replacement becomes the better Choice
Not every station can be rehabilitated. Sewer lift stations could need to be rebuilt when they have a seriously damaged wet well or a lack of capacity for structural strength.
The selection should consider structural integrity, equipment compatibility, construction access to the site, service continuity, and long-term operating needs. Romtec Utilities starts retrofitting and replacing projects by identifying components that will be retained and those that need to be replaced.
The company then develops engineering solutions tailored to the site, as well as preliminary plans as well as budget estimations. Prefabricated components are also beneficial to facilitate installation and reduce some on-site requirements.
The Project isn’t Completion until the Pumps Have In Place
The modern lift station must work as a whole. Before returning a lift-station to normal operation, initial tests, commissioning and verification of equipment are required to make sure that the pumps, controls and related equipment operate according to design.
Maintenance and operation manuals along with the training of operators are vital. Prior to taking over the responsibility of the station, personnel responsible for maintenance must understand new procedures, equipment and documents.
Retrofitting successfully preserves infrastructure that still has value and addresses the shortcomings that forced modernization.
Municipalities and facilities owners need to look beyond immediate repair. The most successful projects incorporate new equipment into existing structures to maintain essential service during construction. They also prepare the pumping system for continued operation for many years.