Flood risks in Cerne Abbas 30.6.22

This afternoon we looked at a special map of Cerne Abbas showing the risk of ground water flooding. We discovered that there are actually lots of areas in our village that have a high risk of flooding. On our maps there were light blue, slightly darker blue and very dark blue areas to represent areas of low, medium and high risk. We looked specifically at our school and the immediate surrounding area. We talked about how close the river is to our school and how the school field is often very wet and soggy (even in the summer). We talked about how our village is also at the bottom of a valley. We used our hands to represent the valley, pointing our fingers downwards to recreate the two steep hills either side. We talked about how this contributes to the flood risk, especially in the winter when we have more rain.

We watched a very interesting Wessex Water video that illustrated the impact of ground water flooding upon the sewage system. The video explained that some areas are more prone to ground water flooding, particularly areas with chalky ground as the chalk acts as a sponge and holds lots of water. Maybe you could play with a sponge in the bath this week and see how different your sponge feels when it's filled with water and when it's been squeezed out. The video showed the pipes and the journey that waste water (from our toilets, washing machines/dish washers) travels from our houses and underneath our roads.

On our walk today we took a copy of the flood risk map. On our way we noticed lots of manhole covers. We realised that there must be lots of pipes underneath the road that we can't see, taking all our waste water out to the recycling centre. We talked down 'Kettle bridge lane' as it looked like there was a big patch of dark blue there on our map. We walked into the carpark and noticed something very interesting behind the fence. Lots of children could say it was a dam and knew that it would help to stop the river flooding. It was especially interesting as we couldn't actually see any water. We decided we should come back at different times of the year to see what is different and if the water levels change, particularly in the winter.

It might be interesting to have some conversations at home about where the water goes when it leaves your house. Can you spot any manhole covers close to your house? Are there other houses close to where you live? What happens to the water we use in the shower/bath? Does the water we flush down our toilet end up in the sea?

Here is a brilliant short video to watch explaining more about the water cycle and to explain where our water comes from: https://www.youtube.com/watch?v=tYFTEembPR0