When the pumping distance becomes too great for any one pump, Japanese experts Tsurumi recommend installing wastewater pumps in series. Sometimes construction projects require a level of performance that cannot be fulfiled by any one pump.

One example is the Koralmtunnel in Austria, which at 32.8km will be the longest rail tunnel in the country. Its construction presents a serious geotechnical challenge. Exploration tunnels are currently being built to evaluate the feasibility of the route, which will pass at depths of up to 1200m.

Contractors Max Bögl and Swietelsky are already on site carrying out this initial phase of the project. Starting from the west portal, the 2.6km long ‘Mitterpichling’ section is close to completion. Work has also begun on the 6km long ‘Paierdorf’ connection tunnel, where the groundwater had to be delivered upwards via the 120m high supply shaft.

“Considering the scale of the task it was unsurprising that no single-solution pump could be found at an acceptable cost,” says Tsurumi. “To solve the problem we developed an efficient cascade connection system. Two rising pipes are installed in the shaft and smaller pumps are fitted at 40m intervals. The units are equipped with a pressure relief valve, so that the accumulated water does not damage the mechanical seal.”

At the base of the shaft the abrasive groundwater is channelled into a basin, into which the lowermost pumps are submerged. “This solution has delivered such positive results that 17 Tsurumi pumps are now being used on the project,” adds the company.

The pumps come from Tsurumi’s KTZ-range. The multi-purpose pumps, designed for tough jobs are best sellers for company, whose European operation is headquartered in Düsseldorf, Germany. The range includes 250 models offering delivery volumes of up to 50m3/minute or 170m head. The model currently installed on the ‘Paierdorf’ site has an 11kW motor and is equipped with a four inch coupling, which can deliver 1440 litres per minute.

Tsurumi (Europe)


Tsurumi A Tsurumi Pump