The wastewater lift station of a municipality is old. The pumps are at the final stage of their life and the controls are dated as well as the access hatch is degraded. The concrete wet well is sturdy and solid.
Should the station be gone? Not necessarily. The best question to ask is whether the existing infrastructure can support the pumping system of the latest standards, without compromising reliability and capacity.
Image credit: romtecutilities.com
A carefully engineered pump station retrofit can preserve valuable infrastructure while replacing components that no longer meet operational requirements.
Start with the Structures Nobody Would Like To Replace
The wet well is typically one of the more expensive and disruptive components to replace because it is located underground, linked to existing piping, and essential to the collection of wastewater.
If the concrete structure remains in good condition, retaining it could decrease excavation and construction work.
The deterioration of the area around the access hatch could affect this decision. Romtec Utilities has identified wet-well hatch replacement as a crucial retrofit. Instead of affixing a new hatch to a damaged concrete structure replacement of the entire top slab might provide a more durable solution. This method can increase accessibility and improve the functionality of the structure without re-building the entire wet well.
A new pump improves the engineering
Imagine a neighborhood which has seen significant increase since the opening of its lift station. It is possible that the existing pumps are no longer sufficient to handle the increasing wastewater flow.
An upgrade to the pumping station could include higher horsepower pumps, however the selection of equipment is not independent of the rest of the system. The more powerful pumps could require modifications to elbows for discharge, pipes valves, electrical controls and other elements.
Engineers must also consider the hydraulic requirements of the system. This includes the flow rate as well as the dynamic head total. If you decide to install a larger pump without evaluating these conditions, it can cause problems with operation rather than addressing them. Planning for future capacity during the initial design phase can help later expansions to be much easier.
Keep Wastewater Moving during Construction
Retrofitting wastewater pumps is a unique problem which isn’t faced by other construction projects. The station could need to be operational during construction.
Contractors continue to work and the wastewater will continue to flow. Based on the nature of the project, temporary bypass pumps may be required to keep services during removal and the installation of existing equipment.
Romtec Utilities addressed this type of issue at the Federal Law Enforcement Training Center in Brunswick, Georgia.
The project involved the replacement of two older wastewater lift stations in the meantime, and maintaining the operation at the facility. Site-specific engineering, packaged replacement systems, and bypass pumping strategies were used to allow for the existing station footprints as well as operational needs. This case illustrates the importance of taking time to think about the sequence of construction prior to constructing.
If you think replacement is the better option, replace it.
Each station is not able to be rehabilitated. Sewer lift stations might need to be rebuilt for a damaged or insufficiently functioning wet well. capacity for structural strength.
The decision must take into consideration structural integrity, equipment compatibility accessibility to construction as well as service continuity and long-term operational requirements. Romtec Utilities begins retrofits and replacements by identifying elements that will remain as well as those which need replacement.
The company also develops engineering solutions that are specific to the location, including preliminary plans and budget estimates. Prefabricated parts are also helpful for organizing installation and reducing certain requirements on site.
The Project is Not Fully Complete Until the Pumps are In Place
Modernized lift stations should function as a system in one. Prior to returning the lift station back to service, startup tests and commissioning are a way to make sure that the pumps and controls as well as other equipment are performing according to an approved design.
Maintenance and operation manuals and also training of operators, are essential. Maintenance workers must be aware of the new equipment, operating procedures, and documents before they can assume responsibility for the station.
Retrofitting infrastructure successfully preserves its value, while addressing limitations that led to modernization.
Municipalities and owners of facilities must think beyond repairs that are immediate. The most successful projects integrate the latest equipment in existing structures to maintain essential service as construction progresses. They also prepare the pumping system for continued running for a long time.