Malham, the River Aire and other ‘water features’
Airehead is where the River Aire officially starts. It is about half a mile south of Malham in the Yorkshire Dales. Click on any image to see a larger version (especially useful for maps).
At Airehead, water comes out of the ground. This is called a spring. Airehead is a large spring, and we saw a small one too. We also saw springs at Gordale Scar.
A smaller stream or river that joins another, usually larger stream or river, is called a tributary. The actual join is called the confluence of the two rivers (especially when the two rivers are of approximately the same width).
A shallow section of river that a car or horse could cross is called a ford. The names of many towns and villages are derived from the word ‘ford’: for example, Oxford is where there was a ford where oxen crossed a river (Wikipedia). Here is a ford in Malham.
Waterfalls are where a stream or river flows over a vertical drop. There are two waterfalls in the Malham area: Gordale Scar and Janet’s Foss. The deeper water at the bottom of the waterfall is called a plunge pool. Waterfalls are usually caused by erosion of softer rock.
Where there is a bend in a river, the water flows more quickly on the outside of the curve. The water on the inside of the bend travels more slowly and the current is weaker. As a result of this, the outside of a bend is likely to show erosion where the water has rubbed away the rock and soil. On the inside of the bend, you are likely to find sand or pebbles that have been deposited because the water is not powerful enough to wash it away.
A weir is a low dam built across a river to raise the level of water upstream or regulate its flow. We saw two weirs: one at Gargrave and one at Saltaire. The town of Saltaire was named after Sir Titus Salt, who owned and built the town and its mill, and the river Aire.
The river Aire continues down the Aire valley past Apperley Bridge and into Leeds. The river gets larger as more and more tributaries ‘feed it’ with water that has fallen on the countryside.
The Aire does not reach the sea itself. It is quite a small river and eventually becomes a tributary for the larger River Ouse at Airmyn. The River Ouse (and the River Trent), eventually become tributaries for the massive River Humber that joins the North Sea near to the city of Hull.
On residential, Year 5 do the Ingleton Waterfall Walk. It is usually impressive but nothing like the scene on August 22nd 2016:
What could be the effect of this powerful surge of water as it rushes down the gorge?
This film also shows water gushing from White Scar cave that is sometimes visited as part of the residential. How had the water got into the cave?