On Tuesday 14th November, all members of LC2 listened to a talk by Rob Jansen from Severn Trent Water.
Severn Trent supplies fresh drinking water for 4.6 million homes and although 71% of planet Earth is covered by water, only 1% safe is to drink. The process of water purification is part of the new GCSE chemistry syllabus and so we learnt about what the stages are, which included: screening to remove large branches and other debris, clarification, filtration (where small insoluble particles are removed), and filters of activated charcoal (which remove pesticides and other chemicals). Finally chlorine is added to kill pathogens that can cause disease.
We then learned about sewage and looked at how a sewage farm deals with waste, this included some very important messages about what is and what is not safe to flush down the toilet. The bottom line is that only the three Ps can be flushed - pee, poo and paper. Wet wipes and fat cause terrible blockages in the sewers which costs millions of pounds to deal with. Each sewage farm produces two huge skip loads of insoluble waste (mostly wet wipes) each day, which is transported to landfill.
This was a very informative session which we really enjoyed.
Hannah and Jessica, LC2
