A disused wastewater liftstation can be located in a municipal. The pumps are nearing the limit of their lifespan The controls are old and the access hatch has deteriorated. Although the concrete wetwell appears solid structurally, it requires to be updated.
Do you think the station should be demolished and rebuilt? Not necessarily. The more important question to consider is whether the current infrastructure will be able to support pumps that meet the latest standards, without compromising reliability and future capacity.
Image credit: romtecutilities.com
Retrofitting an pumping station that has been meticulously designed could save valuable infrastructure, and can also help in replacing parts that are no longer in compliance with the operational standards.
Start with the structure isn’t being replaced by anyone.
It’s expensive and time-consuming to change the wet well since it is submerged in the ground, connected to pipes and is vital for the collection of wastewater.
The concrete structure can be retained to decrease excavation and construction work.
However, the deterioration of the access hatch could complicate the process. Romtec Utilities identifies wet well hatch replacement as a standard retrofit requirement. Instead of affixing a new hatch to a damaged concrete structure replacement of the entire top slab may provide a more durable solution. This could increase the accessibility to the structure and extend its lifespan, without needing to replace the entire structure as well.
A More Powerful Pump Modifies the Engineering
Imagine that a residential area has exploded in size from the time of the first lift station installation. Existing pumps may not be able to deal 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 must also consider the hydraulic requirements of the system, including the rate of flow and the dynamic head total. If you install a bigger pump and do not consider these aspects it could create operational issues rather than solve the problem. Making plans for future capacity in the initial design can allow for later expansion much more easily.
Make sure that the wastewater is kept moving during Construction
Retrofitting a wastewater pump station could be a new challenge. As with other equipment replacement projects, the station must continue to operate during construction.
Even when contractors are busy the wastewater still flows in. Based on the nature of the project an interim bypass pumping system may be necessary to ensure the service until existing equipment is taken away and new components are installed.
Romtec Utilities was able to take on this challenging task at the Federal Law Enforcement Training Center, Brunswick, Georgia.
The project involved replacing two of the old wastewater lift stations in the meantime, and maintaining the operation at the facility. Site-specific engineering packages, replacement systems for packaged equipment, and bypass pumping techniques helped adapt to the station’s footprints as well as operational requirements. The case study illustrates the importance of focusing on construction sequencing before installation begins.
If you think replacement is the better alternative
Each station is not able to be repaired. If the sewer lift station needs to be replaced due to a seriously degraded well, structural constraints or major changes in the needs for hydraulics, it may be more appropriate to replace the station rather than alter.
The choice should take into account structural health, equipment compatibility accessibility to construction to the site, service continuity, and long-term operating requirements. Romtec Utilities begins retrofits and replacements by identifying parts that are to remain and those which need replacement.
From there, the firm creates engineering solutions for specific sites including preliminary designs, as well as budgetary estimates. Prefabricated parts can also help facilitate installation and cut down on needs for construction on site.
The project won’t be finished until the pumps kick in
The modern lift station needs to be able to function as a system. Before returning a lift station to normal service, restart testing, commissioning, and equipment verification are necessary to confirm that the pumps, controls and other equipment are operating as designed.
Operator training and operation and maintenance manuals are equally crucial. Maintenance personnel must be familiar with the latest equipment as well as operational procedures, as well as the necessary documentation prior to taking charge of the station.
An effective retrofit will preserve the infrastructure that is still valuable as well as addressing the weaknesses which led to the need for modernization.
Municipalities and facility owners need to think beyond immediate repairs. Most successful projects blend new equipment and existing structures. They provide essential services while construction is underway and set up the pumping system for a lifetime of operation.