We took a walk down to the Umgeni river which runs past our school and is one of the most important rivers in the area. It is the river that feeds Midmar dam and in turn provides water for millions of people living Howick, Pietermaritzburg and Durban. We wanted to see what the quality of water was like as quality is as important as quantity in many ways.
We used the miniSASS and found 3 groups of invertebrates: Mayflies, other mayflies and water beetles. The pH was around 8 which is within the range for most aquatic animals and the temperture was around 14degrees. We also did the Phosphate and nitrate tests which were low 0.2 and 0.02ppm respectively, a relief to know that there is no pollution coming into the Umgeni at this point, however we do know that it is a very different story downstream when it gets to Howick..
We also realised that the readings could be different during Summer, the rainy season where there would be a lot more run-off from the farm lands around which could result in a higher P and N reading as farming in the area uses lots of fertilizers and pesticides.
We then went back to the classroom and wrote up a summary of our trip to the river - we drew pictures too and have sent these letters to a WE school in Ireland called Berring NS who have very kindly raised 400 pounds for our school to help us fix up our rain water harvesting systems!