Pump Station Anatomy

Understand the key components, fittings and features of a Harlequin Pump station

Pump stations are made up of several components, each with an important role in collecting and pumping wastewater to its discharge point. But what are the different parts, and what does each one do?

In this guide, we’ll explain the main components of a pump station, how they work together and the common fittings and features you may encounter.

1550 Pump station - main

What is a pump station?

A pump station is a tank and pumping system designed to collect and automatically move wastewater from one location to another when it cannot flow by gravity alone.

Wastewater enters the underground tank and collects until it reaches a set level. A float switch activates the pump, which then pumps the wastewater through a discharge pipe to its required destination, such as a sewage treatment plant, septic tank or mains sewer.

Pump stations are commonly used where the outlet is higher than the incoming drainage pipe, where there is insufficient natural fall, or where wastewater needs to be transported over a longer distance.

How does a pump station work?

A pump station collects wastewater in an underground tank and automatically pumps it to a higher level or another location when gravity drainage isn’t possible. As wastewater enters the tank, the water level rises until a pump float activates the pump. The pump then removes the wastewater through the discharge pipe. Once the water level falls to the set level, the pump switches off.

Pump stations are available with single or twin pump configurations, depending on the application and level of reliability required.

Single Pump Stations

A single pump station uses one pump to move the collected wastewater. The pump is automatically controlled by float switches, starting when the wastewater reaches the required level and stopping once the level has fallen.

Single pump systems are commonly suitable for smaller domestic applications where one pump provides sufficient capacity.

Twin Pump Stations

A twin pump station has two pumps working together as part of the same system. The pumps are typically controlled so that they alternate during normal operation, helping to balance usage and wear. If the incoming flow increases, both pumps can operate together where the control system allows.

Twin pump systems also provide additional resilience. If one pump becomes unavailable, the second pump can continue operating.

Twin pumps are often considered for larger domestic, commercial or higher-flow applications, where additional pumping capacity or greater operational resilience is required.

Pump station components explained

Below you will find a useful infographic explaining the key parts of a pump station. The pump stations will vary based on the supplier and method of manufacturer but most will resemble the below in most parts. 

Options for the Pump Station

The Harlequin pump stations have 3 variations, each of which can come with a single or twin pump. 

Effluent pumps 

these are drainage pumps and are suitable for following a treatment plant, septic tank or moving surface water. These ones are not suitable for pumping raw sewage. 

Sewage pumps 

these are solids handling vortex pumps , they pump sewage up to a treatment plant or other suitable discharge point. It is important that ONLY sewage and toilet paper are flushed when using these pump stations. 

Grinder pumps 

these are also solids handling pumps for sewage, however, these are more accommodating for sites where you have less control over what is being flushed. For example, public toilets, campsites or rental properties

Single pumps

Single pump stations come with one submersible pump with integrated float switch. It is recommend to have a high level alarm fitted – this will indicate when the water or sewage limit has risen above the safe operating levels. 

Twin pumps

Twin pump stations come with 2 submersible pumps and a high-level alarm as standard. The twin pump station provides increased reliability and continued operation should one pump experience a fault. (all pump sizes, other than the 450 Litre, have the option of a twin pump)  

How often does a pump station need servicing? 

The servicing frequency for a pump station depends on the type of pump, how frequently it is used, the amount and type of wastewater being pumped, and the manufacturer’s recommendations.

As a general guide:

  • Regular checks – Periodically inspect the pump station for unusual noises, smells, leaks or alarms, and check that the pumps are operating correctly.
  • Routine servicing – Pumps, floats, valves and electrical components should be inspected and maintained in line with the manufacturer’s recommended schedule.
  • Tank cleaning – The pump chamber may need periodic cleaning to remove accumulated silt, grease and debris that could affect the pumps or floats.
  • Pump inspection – Pumps should be checked for blockages, wear and correct operation, particularly where they handle solids or wastewater.
  • Emergency maintenance – Any high-level alarm, pump failure or unusual operation should be investigated promptly to help prevent an overflow.

For commercial or heavily used systems, more frequent servicing may be required.

💡Always follow the manufacturer’s maintenance instructions for your specific pump station, as servicing requirements can vary between models and applications.

Choosing the right pump station 

Choosing the correct pump station is important to ensure it can handle your wastewater requirements and suit the conditions of your site. There are several factors to consider:

  • Capacity – how much wastewater will the pump station need to handle?
  • Application – is it for a domestic property, commercial premises or another application?
  • Pump type – would a single or twin pump configuration be most suitable?
  • Pump performance – what flow rate and pumping head are required?
  • Inlet and outlet levels – how far and how high does the wastewater need to be pumped?
  • Tank size – is there sufficient storage capacity for the expected flow?
  • Pipework – what size and length of discharge pipework will be required?
  • Site conditions – is there suitable space, access and ground conditions for installation?
  • Power supply – is a suitable electrical supply available for the pump and controls?
  • Maintenance – consider access to the pump, floats, valves and other components for servicing.

Not sure which pump station you need?

Our team can help you identify a suitable pump station based on your application, expected flow, pumping distance, head requirements and site conditions.

Contact Us Browse pump stations

Why Choose A pump station?

Key benefits include:

  • Efficient wastewater transfer 
  • Suitable for challenging sites 
  • Automatic operation 
  • Flexible installation 
  • Single or twin pump options 
  • Additional resilience 
  • Reduced risk of backflow 
  • High-level protection
  • Range of capacities 
  • Suitable for a range of wastewater applications 

💡 Important: The correct pump station depends on factors such as expected flow, pumping distance, pumping height (head), tank capacity and site conditions. Always check the manufacturer’s specifications and installation requirements before choosing and installing a system.

A sewage pump station is typically required when a property or drainage point sits below the level of the main sewer or intended discharge point. It may also be needed where wastewater has to travel across a site and there is insufficient fall for a conventional gravity drainage system.

Typical applications include homes, extensions, basement bathrooms, rural properties, commercial buildings, holiday accommodation and developments located some distance from the main sewer.

Choosing the correct pump station involves more than simply selecting a tank capacity. The amount of wastewater being produced, horizontal pumping distance, vertical lift (head), incoming pipe depth and required flow rate can all affect which system is suitable.

If you're unsure, provide as much information about your project as possible before ordering so that the requirements can be checked and a suitable system identified.

Ideally, you should know:

  • What is being pumped – sewage, foul water or other wastewater
  • Number of people or properties being served
  • Incoming pipe diameter
  • Incoming invert depth
  • Approximate horizontal pumping distance
  • Approximate vertical lift
  • Intended discharge point

For more complex installations, additional site information may be required before the correct pump and chamber combination can be specified.

A single pump station contains one pump and is commonly used for smaller domestic and lower-demand applications.

A twin pump station contains two pumps, providing additional capacity and redundancy. Depending on the system, the pumps may alternate during normal operation to share the workload, while the second pump can provide additional capacity or backup if required.

Twin pump systems are often considered for larger, commercial or more critical installations.

A sewage pump station uses a pump designed to handle foul wastewater and the solids normally associated with domestic sewage. However, not every wastewater pump is suitable for handling solids.

The type of wastewater being pumped should therefore always be considered when selecting a system rather than choosing solely by chamber capacity.

A pump station moves wastewater rather than treating it. Depending on the drainage design, it may pump to a mains sewer, septic tank, sewage treatment plant or another suitable discharge point.

The appropriate destination will depend on the individual site and drainage requirements.

Yes. The pumps require an electrical supply to operate. Depending on the system, control panels and high-level alarms may also be fitted.

Electrical connections should be installed by a suitably qualified person and in accordance with the manufacturer's installation requirements.

During normal operation, the pump activates automatically as wastewater reaches its operating level. If the pump fails, there is a power interruption or the discharge becomes blocked, the level inside the chamber can continue to rise.

A high-level alarm can provide an early warning of a problem, allowing action to be taken before the chamber reaches capacity.

Yes. A pump station should be periodically inspected and maintained to ensure the pumps, floats, pipework and controls continue to operate correctly.

Maintenance requirements depend on the system and its level of use, but regular servicing can help identify wear, blockages and other potential problems before they result in a system failure.

Some underground pump stations can be installed in areas subject to vehicle traffic when the correct installation method and appropriately load-rated access cover are used.

The chamber itself should not automatically be assumed to withstand vehicle loading. If the proposed installation is beneath a driveway or trafficked area, the requirements should be checked before ordering.

Yes. Pump stations can be quite technical to specify, particularly where wastewater needs to be pumped over a significant distance or elevation.

Provide the type of wastewater, number of users, incoming invert depth, horizontal pumping distance and vertical lift where possible. These details can then be used to help identify a suitable pump station for the application.

Looking for a sewage treatment plant?  View our complete range.

View the range