Frost fairs held on the frozen Thames are well known but rarely is heard of the occasions when the Thames in London has been so low that people have been able to cross it safely on foot, an event that was much rarer in occurrence than the frost fairs. Here are a very few occasions from some sources of the Thames in London running very low.

1114: "This year was so great an ebb everywhere in one day as no man remembered before so that men went through the Thames both riding and walking east of London Bridge"
1114, April 4th: "River Thames in London so dry that children waded over between the bridges and the town. Under London Bridge only knee deep."
1114, October 10th: "The Thames on that day suffered a great want of water; for between the bridge and the Royal Tower and even under the bridge, the water of the river was so diminished, that not only horses, but also an innumerable crowd of men and boys walked through it, the water hardly reaching their knees."
1158: "An earthquake happened in many places through England and the River of Thames was dryed uppe, that at London men might walke over the same dryshod."

1281: "So great a drought than men passed over the river Thames dryshod between Westminster and Lambeth and over the Medway between Strood and Rochester."

1541: "A remarkable drought; almost all the small rivers dried up and the river Trent diminished to a straggling brook. The river Thames so low that the seawater even at ebb, extended beyond London Bridge."
1591: "The Thames was so dryed up, that a man might ride over it on horseback near London Bridge."

1592 September 5th: "One standing on the shore of the Thames could not see any water in it from London Bridge to Westminster"

1687 May 12th: "This day there was such a storm of wind as had seldom happened, being sort of a hurricane. It kept the flood out of the Thames so that people went on foot over several places above bridge."
1716 September 14th: "A very remarkable phenomenon occurred at London Bridge, when in consequence of the long drought, the stream of the river Thames was reduced so low and from the effect of a violent gale at WSW was blown so dry that many thousands of people passed it on foot both above and below the bridge through most of the arches. The channel in the middle of the river was scarcely ten yards wide and very shallow."

If only weather records were kept in those days - Those descriptions imply that we've had much drier periods than the likes of 1976 in the past.

Quite possibly so but also need to bear in mind that the Thames Embankment was not built until the mid 19th century and this constrained the river to a much narrower flow area than previously. By inference the river would have been faster flowing and deeper after this construction work in central London at least

Then there's the earthquake, some kind of uplift temporarily holding back water?

An unusually low tide coinciding with a period of extended drought?

However the same can’t be said of the Trent which one report mentions. It would be interesting to know where on the river this refers to.

One thing’s for sure and that’s we seem to reluctant to understand or consider historical evidence when considering the magnitude of any current weather event.

I do believe the Thames is now regularly dredging which would stop this happening again.

I worked in Canary wharf for about 5 yrs and used to stay in the hilton docklands, which if you dont know connects to Canary wharf via a small ferry across the thames.

I stayed here for 1-2 yrs with no issue at low tide... then around 2012/3 the tide ran so low that the ship could no longer dock on the jeti. It was literally mooring in approx 1-2 ft of water. below that and the ferry would stop. Once the tide turned the ferry would switch back on. This happened more than a dozen times, but i cant remember happening since...

I always thought this was tidal related, but thinking about it, the river is still flowing out, and still narrow enough to be affected by whats coming down the river.

I think I remember that in Richmond as well (which is also in the tidal section)

The river was so shallow that people were standing on stony outcrops in mid stream with metal detectors as that part of the river is very rarely above water level

There is quite a high difference between high and low tide on this strtch of the river and through central london so when there is a long dry spell and spring tides, then low tide appears just like a trickle of water in mid stream

In wet spells and spring tides, you can also get very high water levels as I came across in Richmond a few years ago (after I'd gone to get my wellies) which tooka  few people in the White Cross by surprise

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