Overpumping & Bypass

WJ Groundwater carry out temporary overpumping and bypass pumping of water or sewage effluent during construction, maintenance, repairs and upgrade works.


Our experience includes draining lagoons and ponds, overpumping sewage and water from manholes and chambers, constructing and operating bypass systems for sewage treatment works, carrying out emergency works to pump away flood and rain water, and even temporary diversion of natural water features such as streams and rivers. We offer cost effective solutions that are carefully designed to meet the needs of our clients.

Whilst maintenance and upgrade works are carried out at sewage treatment works, our fleet of electric or diesel pumps can be used to bypass sewage from one section of the treatment works to another. Whilst pumping sewage it is important to ensure that there is no risk of spillage, damage or malfunction of the overpumping system. To provide confidence 100% standby pumps are used as backup, filter screens are used on suction hoses and pumps to reduce risk of blockages from rags and large objects, and HDPE pipework are often used where high flows are expected.

To design an effective overpumping system it is important to understand:

  • access constraints on site
  • noise pollution constraints due to working in or next to residential areas
  • minimum and maximum flow rates
  • duration of works
  • size of rags and suspended solids
  • distance between suction and┬ádischarge points.

This information is used to choose type and capacity of overpumping system, and what levels of backup, monitoring, supervision and alarms are required.

WJ have a fleet of pumps with large solid handling capacity ideally suited to pumping sewage effluent, including electric sump pumps and diesel surface pumps. Whether your overpumping requirement is 10l/s or over 10000l/s WJ Groundwater have a solution.

Lower Running Costs & Diesel Management

We are running a fleet of highly fuel-efficient, remotely monitored pumps and generators, these are all maintained in excellent working condition, along with an asset renewal program to ensure the fleet is continually updated.

  • Our new generators are powered by Volvo Penta industrial engines, these are powerful, reliable, very economical and fitted with DSE (Deep Sea Electronics) remote communication interfaces for optimum efficiency.
  • Our latest diesel pumps are fitted with Smart Controllers, with manual, automatic or remote starting and stopping capabilities, and alarms for engine on/off.

The generators and pumps monitoring systems send data on their running parameters and operations to ensure ultra-efficiency and reducing site supervision costs.

These systems are providing very cost-effective pumping solutions, so much so, we are pleased to offer dewatering and over-pumping rates including the supply and management of diesel.

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WJ Philippines Projects

We deliver an outstanding service to clients of all size, from simple residential dewatering to large-scale national projects.

Dan CarpenterOverpumping and Bypass