When pumping wastewater and sewage, reliability, solids handling capability, and ease of maintenance are paramount. Self-priming pumps offer an alternative to submersible pumps in wet wells — with advantages in safety, maintenance, and long-term costs. In this article, you will learn how self-priming pumps are deployed in wastewater and sewage applications, what challenges arise, and what Gorman-Rupp solutions are available.
Why Self-Priming Pumps for Wastewater?
Traditionally, submersible pumps are used in sewage pump stations and wastewater pumping stations. The pump is then located in a wet well, directly in the medium. This creates challenges: maintenance takes place below fluid level, staff must work in confined spaces, and failures result in longer downtime.
Self-priming pumps are installed dry and above ground. Maintenance is safer and faster to perform. The pump draws the wastewater through a suction line, without having to be in the medium itself.
For more information about the differences between both pump types, read the comparison article on self-priming pump vs. submersible pump.
Challenges in Pumping Sewage Water
Sewage water is not a simple medium. Its composition is unpredictable and constantly changing. Typical challenges:
- Solids and fibers.
Sewage water contains wipes, fibers, plastics, and other waste. This requires a pump with sufficient solids handling capability and a clog-resistant impeller. - Grease and deposits.
Grease can accumulate in the pump housing and suction line. A self-cleaning sump system prevents deposits in the system. - Corrosion and wear.
H₂S (hydrogen sulfide) and abrasive particles accelerate wear. Material of construction and wear parts must be adapted to this. - Fluctuating flow rates.
Sewage water experiences strong flow fluctuations (dry weather vs. peak rainfall). The pump must operate reliably over a wide duty range.
Self-Priming vs. Submersible Pump at Sewage Pump Stations
At sewage pump stations, dry-installed pump chambers with self-priming pumps are increasingly being used instead of wet wells with submersible pumps. The main reasons:
- Maintenance takes place above ground, without confined space risks
- Failures can be remedied faster thanks to inspection covers and shimless adjustment
- The availability of the pump station is higher due to shorter maintenance stops
- The Total Cost of Ownership is often lower
An above-ground pump station also offers advantages in terms of safety and working conditions. Read more about the benefits of above-ground pump stations.
Gorman-Rupp Solutions for Wastewater
- Super T-Series®
Self-priming centrifugal pump with solids handling capability up to 76 mm. Available with the Eradicator® Solids Management System for clog-resistant operation. Discharge sizes from 50 mm to 250 mm, maximum flow rate up to 215 l/s. Warranty up to 5 years. - Super U-Series®
Self-priming pump with high-efficiency multi-vane impeller (up to 75% pump efficiency). Suitable for municipal wastewater and WWTP applications. Dimensionally interchangeable with the Super T-Series®. - Ultra V-Series®
Designed for the heaviest solids handling applications, including sewage water with wipes, fibers, and other difficult-to-pump materials. - Reliasource / SCS
Modular pump station system with self-cleaning sump. Above-ground maintainable, suitable as a complete sewage pump station or lift station. Replaces traditional wet wells with submersible pumps.
View the complete overview of self-priming pumps on the product page.
Benefits: Safety, Maintenance, and Availability
In summary, self-priming pumps for wastewater and sewage offer the following benefits:
- Safety — no work in confined spaces, no contact with the medium during maintenance
- Service-friendly — above-ground access, inspection cover, quick impeller and seal replacement
- Availability — shorter downtime due to easier maintenance
- Lower TCO — fewer labor hours, fewer emergency measures, longer service life
For more information about the cost structure, read the article on costs and TCO of self-priming pumps.
Need advice on the right pump for your sewage application? Contact our pump specialists.
