Group 1: Water quality measurements and surface water sampling

The date was 26.9 and our tasks was water sampling and water quality measurements. Weather was partly cloudy and athmosphere temperature was between 11 and 14 °C. There was no rain, so it was perfect day fo those experiments. We were participated by Kerkko, Svenja and Antti.

Water quality measurements

The task involved using a HACH HQ 40d Multi Meter measuring device to determine the following water properties from the sites: Temperature C°, pH, Conductivity µS/cm and oxygen content mg/l. The device had three separate corded sensors for pH, µS/cm and O2 with all of them taking the temperature. They needed to be switched between measurements and the sensor’s heads were placed under the water surface for reading. The pH sensor was kept in a neutralising chemical solution cap when not in use. We also took notes of the environment on the measurement sites.

 

Measurement device

The first location was the start of the output stream of Pieni-Valkeinen. The water was slightly brownish, it had a bit of flow, and the shore bottom gave of a putrescent smell. The second location was the end of the input stream to Pieni-Valkeinen. The wet mossy soil had the same rotten odour as the first site and the slowly moving water was cloudy from suspended solids. The third location was the source of the input stream a residential area runoff pipe creek. The water was stagnant, had cloudy clay appearance and it had brown-yellow iron oxide precipitation on the bottom. The fourth location was the end of the input stream to Iso-Valkeinen. The lake had clearer water than the other locations, the stream had decent flow and there was no specific odor.

Input stream source

Measurement at Iso-Valkeinen

Input stream source 62.93’132"N 27°65'739"E, Input stream end 62.92’941"N 27°65'884"E, Output stream start 62.92’890"N 27°66'227"E, Output stream end 62.92’889"N 27°66'527"E

The measurement results

 

Conclusions

Examining the results we can see that larger water masses in the lakes had higher temperature and oxygen content. The input stream source had clearly least oxygen, and that is probably because the stream was almost dry and water wasn’t flowing at all. On the other hand, in the output stream at lake Iso-Valkeinen had decent flow and much larger water mass, so the oxygen level seems to be three times higher than in the input stream source.

 Conductivity was highest in the upper watershed which could be because of the iron precipitation. Acidity measurements might be off because it took the sensor quite some time to calibrate the fixed pH on the sites. Alternatively, acidity might be linked to how stagnant the water was. 

Surface water sampling

The task consisted of taking samples from the areas surface water from three different locations at the Pieni- and Iso-Valkoinen in the northern part of Kuopio. Important for the water sampling is, to always check to take good water samples (without dirt or other foreign objects), so that the phosphorus, nitrogen, solid content and pH content can be reliably determined in the laboratory.

The three different locations are 1) in front of the input stream and 2) in front of the ouput stream of the Pieni-Valkoinen, as well as 3) in front of the input stream of the Iso-Valkoinen. For better orientation the locations are marked in the following map.

For every location we made sensory observations to check if there are any abnormalities or something unusual. At the Pieni-Valkeinen sampling points there was a putrescent rotten-egg smell especially when standing in the moss and mud. At sampling point 1) the colour of the water is a little cloudy, there are many dead leaves and lake plants at the edge of the lake. Also at location 2) there a many leaves and water plants, the colour is bit cloudy as well as brownish tinted/ has humic matter. In contrast at the Iso-Valkoinen input stream the water is pretty clear and there is no strong smell because of the sandy lake shore.

Front of the output stream

Iso-Valkeinen sampling location

Front of the input stream to Pieni-Valkeinen

To take the surface water samples we used 3 sampling bottles, a sampler with an extension handle to which the bottle can be attached, tape with a pencil to mark the bottles with the group number, date, time and location, also proper transportation equipment is needed.

The process of taking the water samples starts with rinsing out the bottle with lake water. Afterwards the bottle is placed in the extension arm and will be filled about ¾ with the lake surface water at the different locations. The bottle will be marked with important information

After taking the samples they need to be properly stored, which means to be protected from heat changes (optimal 4°C), direct sunlight and shocks. The bottles will be frozen so that they can be examined in the laboratory in a few weeks. 

Sampling equipments

Finished water sample

Conclusions

For us, this kind of examination involves high risk because of our inexperience in this kind of field work. There could have been some mistakes while taking the samples and that could cause some distortion in the results. When the samples are ready for examination, we can try to evaluate based on the results,whether there were any errors in the sampling.

We are going to exam the samples in the laboratory in a few weeks, so we dont have any results yet to make precise  conclusions. Although we can make assumptions based on our sensory evaluations. For example, in lake Iso-Valkeinen the water is much clearer than in lake Pieni-Valkeinen and there is no rotting smell on the onshore off Iso-Valkeinen. It is to be assumed that the water from Pieni-Valkeinen has at least more solid materials and is more phosphorous than lake Iso-Valkeinen.