What do the numbered boards standing in rivers mean? What are they measuring?

Answer 1

Water level in order to Prevent floods, because you can change the flood prevention methods e.g put in higher banks, change flood gage. If the water is going over the normal flood level frequently. They have been around for years

Answer 2

They are measuring the height of the river, ie water depth, which varies dependent on rainfall upstream, height of the local water table, state of the tide if the river is tidal etc.

Why, in some cases to show if the river is navigable and in others to indicate the likelyhood of flooding/the river bursting its banks. A further reason is to indicate the health of the river. Too little water in the river due to water extraction or extended periods of drought can mean a reduction in oxygen levels which can lead to the death of the fish population and a reduction in flow can also lead to a build up of toxins/effluent which would normally be flushed away or diluted substantially.

Answer 3

They are measuring the depth of the river to study the seasonal water rises in the river. So when there is a flood they can see how high it went and then know that it can do it again so build some flood defenses to try and stop it from flooding again.

Answer 4

Water level as a guide to flood prediction. On most UK rivers a far more sophisticated network of solar-powered electronic transmitter sensors is now in place to continuously monitor levels but the old boards still remain, probably because they're too much trouble to remove.

Answer 5

The numbered board display the water depth levels.

Answer 6

These numbers usually indicate the depth of water in feet or metres.

They show you the state of the water (usually river or tide)

By the side of the road they are placed in sections liable to flooding to give the motorist some idea of the depth of water he might (or might not) have to drive through.

When they have completely disappeared you are in trouble, so make for high land, preferably with a pub.

Answer 7

The depth of the water. I believe they may be in fractions or percentages of fathoms but could just be in old feet and inches. They are there for two reasons.
One is to check the level of the water with regards to flooding, the other is the check the depth of the water so that vessels know that they can clear the bottom.

Answer 8

Probably measuring the height/depth of the water, to help prevent flooding

Answer 9

It displays the depth of the water

Answer 10

These have recently been introduced by the government so people who are concerned about their weight can find out if they are the correct height for their weight.