Taylor River - Is it Really Clean
gained Michelle Mehlhopt 1st place in the environment section (yr 12 - 13), the Best Air and Water Exhibit, and 2nd IN THE FAIR.
Michelle is a 17-year-old from Marlborough Girls' College, who got the idea for her investigation from the recent controversy over the water quality of our local rivers.
Her aim was to see if the Taylor River water met health guidelines and if it varied down its length.
Michelle choose three sites, upstream, Blenheim town centre, and downstream.
To keep the tests fair, all samples were taken from the middle of the river at the same depth at the same time of day, several samples were taken over a long period of time in case conditions changed during a day or over weeks.
To measure the water quality Michelle took field measurements of temperature, pH, clarity (black disc), dissolved oxygen, and then took samples back to the lab to measure available oxygen by titration, and total solids by evaporation.
After finding averages for measurements at each site and looking for patterns and comparisons Michelle was able to determine that the water at all sites does meet with health guidelines.
However the water in town had the poorest quality, as it was least clear had the lowest oxygen levels and highest total solids. Michelle thinks one small tributary may be the cause.
Michelle got help from the Marlborough District Council, her chemistry teacher and the schools science technician.
Some useful advice: "start early, write a timetable / plan and stick to it, keep a detailed log"