A message is in from Claire Shahbazian Bedford of the Wandle Trust. her E-mail address is:- claire.bedford@wandletrust.org
I am leading a project to improve water quality in the River Wandle in Sutton. The project is being funded by the Environment Agency and I am also working closely with the Council. One of the study sites is Carshalton Ponds. This is a very important site within the borough but it currently suffers from poor water quality because of pollutants such as oil, grease and silt. However, there is a good possibility of improving water quality if these problems are tackled because the ponds also receive pure spring water. To begin addressing the problems, next week I will be applying chalk to the ponds. This is non-toxic and breaks down silt and increases water clarity. It counteracts acidity (appropriate for a chalk river like the Wandle) and helps increase oxygen levels and reduce methane levels. It poses no harm to wildlife, people or the environment.
I will be applying the chalk from a boat. The ponds will look whiter and a bit milky for a few days. This should disappear and there will be no other effects. The likely day for this work is Wed 18th December although it will depend somewhat on weather conditions. We will need calm conditions due to the powdery consistency of the chalk. Work will ideally be completed in one day and will certainly take no longer than two days. No roads or access around the ponds will be affected. I have attached a photo to show what this may look like. I will monitor improvements over the coming months. As the silt is deep in places, it is likely that further applications in following winters will be required. We have funding to cover this. This action should also reduce the Council’s costs for managing the ponds in the longer term. I will put up signs around the ponds to explain what is happening to passersby and if anyone has further questions I would be more than happy to answer them. I hope you will help the project by supporting this activity and pass on the news on as widely as possible.Click on:- Siltex-image-credit