Report (Permission Visit) - Grand Cascade Pump Room, Alnwick - August 2015 | Underground Sites | 28DaysLater.co.uk

Report (Permission Visit) Grand Cascade Pump Room, Alnwick - August 2015


28DL Full Member
28DL Full Member
Whilst visiting Alnwick Gardens, a little sign in the Poison Garden caught my eye (read more about the Poison Garden here: http://bit.ly/1wDtjr1) saying that it was possible to go underneath the Grand Cascade, into the pump rooms. An hour later, I found myself here.


These pump rooms control the Grand Cascade, a 90-metre long fountain that forms the centrepiece of the Gardens. The original fountain was the single pool at the bottom, however it was then extended upon from 1997 to 2003. It is the largest of it's kind, and a 'feat of modern engineering'.


7260 gallons of water go down the 21 weirs every minute, along with the 350 litres shot out every second by various fountains and water jets. The two halves of the fountain, the Upper and Lower Cascades, are both controlled separately and have their own individual storage tanks.


The pump room itself is 80 metres long and 10 metres deep; enough room to park 9 double-decker buses. A system of sophisticated software, pneumatic and solenoid valves, and variable speed drives control the mechanical equipment that keeps this monster going.


The computer closest to us in this shot is the central control computer. The display at the top shows each fountain and water jet, and can be configured manually from there. The 3 blue boxes underneath show the quantity of water in each storage tank - in metres however, not litres. This all depends on the depth of the water in the tank. The bottom screen shows the commands and processes that run the 4 different shows that are created by the Cascade.


This pipe alone sends thousands of gallons of water up into the fountain.


This is the main generator for the Lower Cascade. It produces 70 HP, however if it was replaced with a modern generator it could produce double that amount and take up half the space.


First off I'd like to apologise for this picture, it's stuck like that :banghead
Anyway. What we see here is two things: the computer that controls the more technical part of the displays, and the steps that lead all the way around the fountain. If you were to walk up those steps you would get a lot wetter and a lot colder, but you would be able to walk around the whole perimeter of the Cascade.
The box you see to the right *ahem* controls the technical part of the displays. The Cascade also houses lasers, fireworks, smoke machines, LEDs, options to light up each individual pool - all which can be controlled from this computer. The main technician also has remote access to this from his own computer.


Being a 90-metre long, 40-metre wide fountain filled with water, you would expect it to get dirty. However the green tank you see (and the 3 behind it) control the hydrochloric acid that keeps the water clean. Another generator is situated at the foot of these tanks - that's the blue machine you see. The black containers are full of chlorine which is pumped and filtered into the system through that little yellow tube you see on the floor. Divers are sent down every 3 years to clear the bottom of the pools due to silt build-up.


Back here again. This time we see the two main pipes that control the two lower pools. These are connected to the two storage tanks that provide the water for the Lower Cascade, and a whirlpool is created at the bottom of each pool. However, the whirlpool on the left goes the wrong way due to the sheer force of the water coming down. It cannot correct itself.


The red piping you see here has little to do with the Cascade. When the Gardens were being built, a planning request was put forward to build the Treehouse (http://bit.ly/1DYa6bI). However, as the entire structure is constructed of wood yet houses a large kitchen, it needed a state of the art sprinkler system. The Cascade was promptly connected up to the sprinkler system inside the Treehouse, and the water is controlled and transported through the red pipes you see above.


If you've made it this far, congratulations! Hope you've enjoyed :thumb
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28DL Full Member
Interesting and very good write up enjoyed that..:thumb


28DL Member
28DL Member
Hey great post! I was just wondering why are hearing protection needed in the pump rooms? Which of the equipment is noisy? -Thanks