You can see how this sluice channel entrance in the side of the Entrance Lock wall is about level with the control wheel we saw on the far side—if you look closely, you can see it immediately to the left of and behind the modern building in the background. Given what the lockkeeper described to me, I'm confident that this is where the water for sluicing the Gridion clean of silt came from—they fill Entrance lock, then open the sluice to carry water—which must be under reasonable pressure with a full lock—across to the far side where the Gridiron is, washing off the accumulated silt.
Clever, these Bristol engineers: no actual pumping required. Just tides and gravity.
And that's the last of my musing on the Gridiron. I'm not sure why I became so fascinated by a giant Victorian boat-sieve, but I did!
GPS Coordinates:
51.44924, -2.62325
Location: Hotwells
