Walker, who was arguably the most experienced diver in the country at the time, had an extremely challenging job. His task was to descend into the flooded trenches in a primitive and immensely heavy diving suit and level the trenches, by removing the peat topsoil and then laying bags of cement to plug the water coming up from below. Walker's suit weighed dry, and the trenches were cramped and pitch-black; Walker had to feel around with his hands. Additional challenges were that the water was full of bodies and graves, which made the water septic. Walker worked 6 to 7 hour shifts almost every day for six years to achieve this, diving under the majority of the cathedral building. When he had completed his work in 1911, the pump could be used safely to remove the water without disturbing the foundations. In 1911, flying buttresses were added along the length of the south nave to complete the work.
Walker, who was arguably the most experienced diver in the country at the time, had an extremely challenging job. His task was to descend into the flooded trenches in a primitive and immensely heavy diving suit and level the trenches by removing the peat topsoil and then laying bags of cement to plug the water coming up from below. Walker's suit weighed dry, and the trenches were cramped and pitch-black; Walker had t,o feel around with his hands. Additional challenges were that the water was full of bodies and graves, which made the water septic. Walker worked 6 to 7 hour shifts almost every day, for six years to achieve this, divin.g under the majority of the cathedral building. When he had completed his work in 1911, the pump could be used safely to remove the water without disturbing the foundations In 1911 flying buttresses were added along the length of the south nave to complete the work.