Designed to site requirements

INTRODUCTION

Located by Southwark Bridge on the south bank of the Thames, the former home of The Financial Times is undergoing a full refurbishment and upgrade.

We were asked to supply two pumping stations, one foul water and one surface water for the building, which will become the headquarters of a multi-national media company.

The foul station will accept waste from basement level WCs and showers which cannot be gravity drained.

The surface water station will empty a large rainwater attenuation chamber which previously stored water for the building’s sprinkler system.

METHOD

Based on the requirements supplied by our client we specified a 2.4 m diameter by 4 m deep MagnaPro Twin with DN80 vortex pumps with 3-inch galvanised steel internal pipework and discharging to a 90 mm rising main. Straightforward.

However, the pumping station chamber was to be installed below a concrete car park ramp which was 1.5 m thick at that location. This would mean that all servicing and repairs would require confined space entry and man-riding equipment, along with a difficult and unnecessarily risky procedure to remove the pumps.

We extended the guide rails out of the chamber to just below finished floor level and moved the junction boxes up. These changes mean that servicing will be much safer and quicker.

The surface water pumping station is within an 11 m long, 6 m wide and 5 m deep concrete sump, providing over 200,000 litres of rainwater attenuation. It will accept storm water from the roof and surface water from hard landscaping at ground level.

We recommend twin pump sets for all surface water applications because inflow cannot be controlled, and a second pump provides redundancy should the primary pump fail. However, the client requested we design a single pump system. To achieve the necessary total head and flow rate we specified a single 4.9 kW DN150 vortex pump.

The clear opening of the sump is at the opposite end of the chamber to the discharge point. The pipework inside the sump needed to be suspended from the ceiling. Due to the weight of DN150 ductile iron we instead chose to use DN150 electrofusion-welded high-density polyethylene. This pipework will be suitably robust whilst being much lighter.

A platform was assembled within the chamber so our engineers could install the pipework safely.

RESULTS

Both pumping stations have been adapted to site constraints. They will operate reliably whilst being designed for longevity and ease-of-service.

The guide rails were extended out of the chamber and the junction boxes raised to enable future servicing without the need for confined space entry or man-riding equipment.

The control panel is located nearby. It will be hidden and protected by shuttering.

The attenuation chamber is 5 m deep and has a capacity of over 200,000 litres.

A platform was assembled in the sump to allow our engineers to install the pipework safely.

The DN150 HDPE discharge pipe was electrofusion welded.

Our ever resourceful engineers installing the control panel in the rain.

 

FOCUS ON

System design

With over 30 years’ experience of designing wastewater pumping stations, we can specify systems for all requirements and constraints.

We offer no-obligation free site surveys and advice.

Need help with a wastewater pumping or drainage project? Contact our Sales Team at sales@edincare.com or on 01442 211 554 (Option 1).