The sewer lift station in the municipality is old. Pumps are about to expire their service life, and controls need modernization and the access hatch must be replaced. Although the concrete wetwell is solid structurally, it requires to be updated.
Should the entire station be destroyed and rebuilt? Not necessarily. It is important to consider whether the infrastructure in place can support modern pumps without compromising future capacity, reliability, or maintenance access.
Image credit: romtecutilities.com
A thoughtfully designed pump station retrofit can preserve important infrastructure and replace components that no longer meet operational standards.
Start with the Structures That Nobody Will Want to Replace
Wet wells are typically the most expensive and difficult element to replace because they are constructed underground and attached to existing pipes, and vital to wastewater collection.
A concrete structure that is still usable could make it easier to dig and build.
However, deterioration around the access hatch may complicate the choice. Romtec Utilities says that wet well hatches are typically replaced in retrofits. Rather than attaching a new hatch to a damaged concrete structure, replacing the entire top slab may be a better option. This technique can be utilized to increase access and improve the functionality of the structure, without the need for rebuilding the entire wet well.
The design of a more powerful pump is distinct
Consider a neighborhood that has experienced a significant increase since the opening of the lift station. It’s possible that the existing pumps are no longer adequate to handle the increase in wastewater flow.
A pumping station upgrade could involve higher-horsepower pumps, but equipment selection cannot happen independently of the surrounding system.
Engineers also need to evaluate the requirements of the hydraulic system, including the flow and head total dynamic. The installation of a bigger pump before evaluating the conditions may cause more issues than it resolves. Planning for future expansion during the initial design phase will help you to add more capacity later on.
Make sure that the wastewater is kept moving during Construction
A retrofit of a wastewater pumping station presents a problem that normal construction projects for new equipment do not face: the station may require operation throughout the construction.
Even when contractors are busy, wastewater continues to arrive. According to the plan it is possible that a temporary bypass pumping system may be required to ensure service is maintained as the old equipment is removed, or new components installed.
Romtec Utilities embraced this challenge in the Federal Law Enforcement Training Center, Brunswick, Georgia.
The project involved the replacement of two older wastewater lifting stations, whilst maintaining the operation at the facility. Specific engineering for the site and packaged replacement systems and bypass pumping strategies helped adapt to the station’s footprints and operational demands. This is a good example of how the order of construction should be carefully considered before installation.
In the event that replacing becomes the best alternative
Not every station can be renovated. A seriously damaged wet well structure that is not strong enough, or major changes in the hydraulic requirements can make the sewer lift station replacement more suitable than altering the existing structure.
It is vital that the decision taken takes into account structural factors the compatibility of equipment and construction accessibility, as well being long-term operational needs. Romtec Utilities starts retrofitting and replacing projects by identifying elements that will remain and those that will need to be replaced.
The company can then design engineering solutions tailored to the location, including preliminary plans and budget estimates. Prefabricated parts are also helpful to organize installation and reduce the number of on-site requirements.
The Project isn’t Over Until the Pumps Begin to Run
The modern lift station must function as a complete system. Before returning it for regular maintenance, start-up testing and commissioning ensures that the controls, pumps and the associated equipment work according to the design approved.
Manuals as well as training for operators are equally vital. Maintenance personnel must know the new equipment, operating procedures, and other documentation before they take over responsibility for the station.
A successful retrofit helps preserve structures that are still useful as well as addressing the weaknesses which led to the need for modernization.
Municipalities and owners of facilities must think beyond repairs that are immediate. The best projects incorporate new equipment into existing structures to ensure that essential service is maintained as construction progresses. Also, they prepare the pumping system for continued running for a long time.