Thursday 28 April 2011

St. Germans Pumping Station

I was privileged recently to be at a brand new pumping station in the Fens for its official opening. I was there to make a report for BBC Look East.



A pumping station was built at Wiggenhall St. Germans in 1934 for pumping water from the Middle Level Main Drain into the River Great Ouse, and thence to the sea at King's Lynn. Prior to that time discharge by gravity to low tides was possible, but peat shrinkage was making the land sink, and modern building methods were leading to faster rainwater runoff into the drains which fed the Middle Level. Now, if it were not for the pumps at St. Germans, the Middle Level and its tributaries would flood, inundating 170,000 acres of land including the towns of Whittlesey, Chatteris, March and Ramsey. The land has sunk to the extent that even a low tide is higher than the normal Middle Level level. On the day I went, the difference in levels was about 3.4 metres - but the pumps were not on as there had been little rain for several weeks.

Now the time had come to replace the original pumping station, and work started on the new one in December 2006. In April 2010, over a four day period, the old pumps were switched off, and the new station became operational.

I was told why the official opening was a year later, but I can't remember the reason now. Possibly something to do with tidying the site.

Lord James Russell revealed the plaque and pressed a symbolic big green button. His ancestor, William Russell, was the Earl of Bedford. It was he who instigated the draining of the Fens in the 17th century - employing Cornelius Vermuyden - and thus created Britain's "breadbasket", the large area of highly productive arable land.

The tour of the pumping station was fascinating. There are six pumps, each driven by a 1.5 MW electric motor - yes, that's one and a half megawatts! Three pumps can run from the mains electricity, but if four or more pumps are required, diesel generators are used. Each pump has its own 1.7 MW generator, each with a 40,000 litre fuel tank. The engines are V12 units made by Finning. The pumps' impellers are 2.6 metres in diameter and weigh 5 tonnes, and rotate only about one and a half times a second.

When all six pumps are running the station can shift 100 tonnes of water every second - it could empty an Olympic size swimming pool in 25 seconds!

Just as the engineering is awesome, so the building itself is striking. In black, with a glass front, it is beautiful as well as being functional. In a remarkable way it seems to fit in to the surroundings.

7 comments:

No Direction said...

Beautiful engineering.

Andy Tidy said...

Halfie
An interesting days work!
Andy

Brian and Diana on NB Harnser said...

You slipped up there, they probably change the diesel every 12 months, you should have found out who has the contract, it could have meant cheap diesel for life.

Halfie said...

Brian, one thing there wasn't space for in my report was that they can run a maximum of three pumps from the mains. If four or more are needed they have to run up the diesel generators, so I expect there's sufficient turn-round on the fuel for old diesel to be a problem. It's an interesting point, though!

Vallypee said...

What a nice assignment, Halfie! We have a lot of such pumping stations over in these very low lands. Maybe you could come and make a documentary about them some time. A few of them are very old and historically interesting.

Halfie said...

Well that would indeed be fascinating, VallyP, but I'm not let out very often!

Vallypee said...

Bad luck! It might be worth suggesting, though?