A team of hydrogeophysics research students have used advanced GPS and ultrasound to conduct a survey of Forrest Hills lake.
The project was carried out by Lancaster Environment Centre (LEC) PhD students Paul McLachlan, Guillaume Blanchy and Michael Tso together with Building and Facilities Superintendent Andy Quin and involved conducting a topographic survey of the Forrest Hills lake bed and River Conder.
The students, commissioned by the University’s Facilities department, were given two key objectives. Firstly, to assess if the volume of water in the lake meant it classified as a reservoir under the Reservoir Act and, secondly, to assess the difference in elevation between the lake bed and adjoining river.
The survey was completed using LEC’s Trimble differential GPS and an ultrasound water depth sensor to measure the volume of the lake. The differential GPS works by setting up two antennas, one at a fixed ‘base station’ location and another mobile antenna called a rover. While the rover is used to collect survey data (in LEC’s research boat), the base station is able to account for any minor inaccuracies with the rover’s GPS readings, which allows for more accurate measurements be obtained.
“We set up the differential GPS to get x, y and elevation data from all around the lake to get its boundaries,” Guillaume explained. “The base station was set up in the middle of the survey area and we walked the rover all around the lake.”
The final results revealed that the current total volume of the lake is approximately 22,358m3, which puts it below the 25,000m3 limit for reservoir classification. Had the lake been classified as a reservoir, under the Reservoir Act, the University would have had to take extra consideration before developing in the area.
Michael commented: “It was a fun and memorable outreach experience. It allowed us to apply the practical skills we have learnt during our PhD study to help with the University’s Facilities Department.”
Professor Andrew Binley, the supervisor of the students, commented: “It’s great to see research students using their skills to tackle problems of direct relevance to University operations. Hopefully, we’ll see more examples of this kind of engagement and utilisation of the wide range of expertise that the student body offers”.
The lake forms the backdrop of the scenic Forrest Hills complex, the recently purchased award winning venue used for corporate events, conferences, management training and weddings and other functions.