Michael Goodhart and Bruce Huett from Cam Valley Forum visited Gretton School in Girton, Cambridge on 12th October 2023 for a full day to explore the nature of chalk streams with the pupils as part of their sustainability week. The day was organised by the sustainability teacher Yair Doza and the acting head of science Jenny McCran also participated.
Gretton school is for children with Autism from aged from 7 to 19 from Cambridgeshire and wider afield. It has about 140 pupils of differing abilities, some as boarders and others as day pupils.
Four sessions were held in the science lab. Bruce used a powerpoint to elicit responses from the children on their experiences of rivers and chalk streams. He explained how he was involved with a river group that had made significant changes to the river Mel in Melbourn, Cambridgeshire. One of the pupils lived in Meldreth and was able to recount his experiences of playing near the river.
Using slides depicting animals and plants in the river he explored how it was important to maintain a healthy river environment to support biodiversity. The children enjoyed the reference to Ratty, the water vole from Wind in the Willows, and were concerned about the threat to them from predators if water levels dropped. This linked into a discussion of food chains and the role of otters. Otter spraint – a small deposit containing fish bones that otters leave on rocks to attract females has been found in the Mel and interested the pupils.
Some pupils had enjoyed seeing kingfishers and some had encountered leeches, including having their blood sucked.
The Hach kit was used to demonstrate phosphate levels in water, giving a blue colour if phosphate was present. Luckily the distilled water didn’t turn blue but Mel water, from below the sewage works, did. However, surprisingly this was lighter than a sample from Byron’s pool.
Bruce also brought samples of gravel and soft chalk from the base of the Mel to illustrate how the base of the river was formed.
With some classes there was brief discussion on the spirituality of water and the many types of water gods and forms of spring, river and water worship around the world.
Leisure activities in and on water were explored and Michael talked about and showed pictures of his experience of learning to swim in the Cam. Bruce confused one of the pupils when he asked about which stroke he liked to use. He thought it was about stroking a cat!
Michael explained the idea of designating a stretch of the river for bathing.
He also raised the issue of the declining level of water in the streams and the problems of abstraction, over use of water and climate change (illustrated by a slide of a completely dried up Mel). This led into discussions on how we could reduce the amount of water we use, with interesting suggestions from the children. The dangers of flooding were also mentioned.
There were a lot of questions from some of the pupils and this kept Michael and Bruce on their toes.
The school was very appreciative of their efforts and it was an opportunity to widen the profile of Cam Valley Forum and raise chalk stream issues with a new audience.