On board Polarstern there are five networks for sea water:
- Seawater intake at box keel or alternatively a few meters aside of that via conic intake at depth of 11 meter and 10.5 meter respectively. Prior to the pump, the pipe split into two lines (sea also item 2). First line goes to „Klauspumpe“, rotating pump (25 qm/h). The pipes consists of stainless steel. The seawater-taps are available in all laboratories on E-Deck. This water is also used e.g. for cooling of laboratory containers.
- Seawater intake is the same like item 1. After mentioned split, the second line goes to room G-707 and seawater analyze systems “FerryBox” and the pCO2 analyzers. A displacement pump of Sinus type guarantees a minimum damage of bio-cells. Active pressure control devices are installed on each line to scientific analyzer.
- Seawater intake is inside tunnel of cross propeller at depth of ca. 7 meters. Two pumps can be used alternatively: Membrane pump (1-4 qm/h) or rotating pump (4 qm/h). Typically the pumps are providing water through Teflon pipes, but use of stainless steel pipes is also possible. The seawater-taps are available in all laboratories on E-Deck.
- Seawater intake is also inside tunnel of cross propeller at depth of ca. 7 meters. Only one system is supplied by seawater, namely the AutoFIM particle filter.
- Seawater intake at box keel on port side, outlet at box keel on starboard side. The devices supplied by this system is Seabird SBE21 temperature sensor and two Seabird SBE38 thermosalinograph. Both TSG are installed in one Seawater box to be provided by identical water.
The need of seawater must be announced before the cruise in formula "Einsatzplanung". As several scientific groups on board are typically requesting seawater a plan must be established, which group takes water from which network to avaid any conflict/overlap. The operation on board by means of switch on and off the pumps is executed by the ships crew and must be requested by chief scientist the day before.
In dirty by means of not clear waters like in harbours or the Wadden Sea the seawater pumps despite of "Klauspumpe" are switched off to availd soiling of pipes and analyzers.
A full cleaning procedure of pipes can be performed in shipyard only. It must be requested at schiffskoord@awi.de several weeks before shipyard. The rate/quality of cleanness must be outlined at request.
A post cleaning procedure of pipes can be performed during cruise. The time schedule of this cleaning procedure must be planned before the cruise and outlined in formula "Einsatzplanung". The cleaning procedure must be executed in compliance with the ships command and chief scientist.