ABS pumps help dewater Black Forest hydroelectric project

German tunnelling contractor Baresel Gmbh is using a mix of owned and rented ABS pumps on a tunnel dewatering application as part of a major project to build a 1400 MW hydroelectric power station in the Black Forest, close to the border with Switzerland.

The company has bought 11 J 205 (20 kW) pumps with serial connectors and soft starters, and rented four J 205 and six J 84 (9.4 kW) pumps from ABS, to dewater a 1720 m long exploratory gallery in the mountain. At the end of this gallery Baresel will drill further exploratory borings for the main cavern of the power station.

The pumps - built by ABS sister company CARDO Flow Solutions - are being used to continuously dewater the inclined tunnel up to a maximum flow of 50 l /s and at pumping heads of up to 120 m.

ABS suggested chains of three high-head J 205 pumps placed on special horizontal supports and connected in a row using steel tubes, rubber hoses and ABS-serial connectors at the bottom plate of each pump. The power supply to the pumping system incorporates ABS-soft start devices on each pump.

Rental pumps and additional pumps for stand-by and maintenance purposes are also part of the installation. These additional pumps have been used twice since construction started in October 2009; in April and in August when flows reached 37 l/s. The system handled the flows easily and there were no major delays to construction work.

Dietmar Dreyer, segment manager dewatering & rental at ABS Deutschland GmbH, tells IRN that this challenging project is a good example of the combined rental and sales service that it offers to clients.

ABS sells pumps to rental companies and is also a member of the Caterpillar allied vendors programme for the Cat Rental Stores, but it also maintains its own rental fleet for rent to end users of re-rental to rental companies. "With our own rental fleet we cover special demand for very big pumps, special sludge or waste-water pumps and accessories", says Mr Dreyer.

ABS Spain holds the largest stock of pumps - around 2500 units - and Mr Dreyer says there are 750 rental pumps in ABS's European area, covering Austria, Switzerland, Luxemburg and Germany.