By Trista McKenzie
We’ve just returned to Coffs Harbour after a successful week of fieldwork in Sydney! We were able to cover five different sites in Sydney Harbour and Botany Bay, which was really because we had a great field team.
At each site, we made “groundwater wells” by digging in the sand until we reached water. Each well represented a different section of the beach with respect to the tide. We also took surface water samples perpendicular to the shoreline – so that all of our samples lined up in a transect (Figure 1). This allows us to get a better idea of where the groundwater is seeping out along the shoreline. We primarily targeted low tide (because groundwater is driven by gravity and there is the greatest difference in the height of the groundwater level at low tide, meaning we anticipate the highest groundwater discharge), but also sampled at high tide in a few locations.
When it came time for sampling, we had two people sampling surface water, two people sampling groundwater, one person filtering the samples and doing the chemistry, and one person running around, helping as needed. This meant it was pretty crazy for about an hour while we frantically tried to get all of the samples within a short time frame.
After the samples were all collected, we processed some of the samples on the beach. Some samples had to sit for several hours incubating in the ambient water and others had to be drained through manganese fibers. During this time were still keeping busy, but it was definitely less hectic compared to while we were sampling.
The teamwork on this field trip was absolutely amazing – I don’t think I’ve ever worked with such a coherent, hard working team. From sampling, loading and unloading the truck everyday, and cooking meals, our success during this trip was absolutely because of the team effort. I really hope this team can come together again for more fieldwork!
Now it’s back to the lab to process the samples…