The wastewater lift station in an urban municipality is old. The pumps are nearing the limit of their lifespan, the controls are outdated as well as the access hatch is worn out. Although the concrete wetwell appears structurally sound, it needs to be modernized.
Image credit: romtecutilities.com
Should the entire station be destroyed and rebuilt? Not necessarily. The more important question to consider is whether the current infrastructure will support a pumping system that meets the latest standards, without compromising reliability and capacity.
Retrofitting a pump station could be a fantastic method to preserve infrastructure and replace elements that have become obsolete.
Begin With the Structure No One Would Like to Replace
The wet well is usually one of the most costly and challenging components to replace, as it’s hidden, connected to the existing pipes, and crucial to the collection of wastewater.
Retaining a concrete construction that is still serviceable can minimize the digging and construction.
However, deterioration around the access hatch can make the choice. Romtec Utilities identifies wet well hatch replacement as a standard retrofit requirement. Instead of attaching a brand new hatch to deteriorated concrete and replacing the entire top slab may offer a more long-lasting solution. This technique can be utilized to increase accessibility and enhance the structure’s usability without needing to rebuild the entire wet well.
An improved pump can alter the engineering
Imagine a neighborhood that has seen a significant increase in population since the original lift station installation. Existing pumps may not be able to deal with increased wastewater flows.
The improvement of a pumping system may include more horsepower, but this cannot be done without considering the entire system. To get more powerful pumps you might need modify the discharge elbows or pipe. It is also possible to replace electrical controls or valves.
The engineers should also take into consideration the requirements for hydraulics of the system, including the rate of flow and the dynamic head total. Installing a larger pump without evaluating the situation may cause more issues than it resolves. Planning for future expansion during initial design will allow for a much simpler process to grow later on.
Make sure that the water for waste is moving during construction
A wastewater pump station retrofit introduces a challenge that ordinary equipment replacement projects may not face: the station may need to remain operational throughout construction.
The water continues to flow even while contractors are working. According to the study it is possible that a temporary bypass pumping system is needed to keep service running while existing equipment is removed or new equipment is installed.
Romtec Utilities tackled this type of challenge in the Federal Law Enforcement Training Center at Brunswick, Georgia.
The project required the replacement of two old wastewater lift stations while also maintaining the operation of the facility. Specific engineering for the site packages, replacement systems for packaged equipment, and bypass pumping methods helped accommodate the existing station footprints and operational needs. The example illustrates the importance of focusing on construction sequencing prior to the installation process begins.
When replacement becomes the better Choice
It is not possible for every station to be renovated. Sewer lift stations may need to be rebuilt for a damaged wet well or inadequate capacity for structural strength.
In making a decision, it is essential to think about the structural integrity of the building, its compatibility with equipment, the accessibility to construction, the continuity of services and long-term requirements. Romtec Utilities begins retrofit and replacement projects by identifying which components will be left and which need to be replaced.
From there, the company develops site-specific engineering solutions as well as preliminary designs and budgetary estimates. Prefabricated components can assist in simplify installation and decrease on-site construction.
The Project Isn’t Finished When the Pumps Begin to Run
A modernized lift station must operate as an integrated system. Before returning it for regular maintenance, start-up testing and commissioning ensures that the pumps, controls, and the associated equipment work according to the approved design.
Maintenance and operation manuals along with the training of operators are essential. Maintenance personnel must be familiar with new equipment and operating procedures, and the necessary documentation prior to taking responsibility for the station.
Retrofitting infrastructure can preserve its value, while also eliminating the limitations that prompted modernization.
Municipalities and facilities owners need to be aware of the need for more than just immediate repairs. The best projects incorporate new equipment into existing structures and continue to provide essential services even while construction is in progress. They also prepare the pumping system for continued running for a long time.