malside_engelsk

A brook on Vennesla Østhei

Facts about the brook: The brook comes from a swamp from Vennesla Østhei, therefore the flow of the brook varies. It was relatively little water in the brook when we examined the brook, because of little rain during the last week. The upper testingplace the brook was before a housing area, and the second testingplace was after this housing area.
From line 2 the brook goes in pipes under the earth and out into the river of Otra.
The brook goes under the earth between the drawn line 1 and line 2.

Presenting the problem:
We wanted know if the brook was polluted. If yes , we would try to find the causes.
We also measured the pH. We used LaMotte pH test kit
We followed this prosedure.
The classification was done after this methode and this form.

Results:

Smell: It has an aromatic smell of seaweed. (Class 2)

Foam: In some places there is a considerable quantity of foam. (Class 3)

Water appearance: The water is clear, with small particles. (Class 1)

The bottom of the brook: There are slippery stones covered with long thread-like seaweed. (Class 2)

Bottom animals: We didn't find many creatures, the only creature we found was a maggot: Polycentropus flavomaculatus (12 mm) (Class 2).

The pH value in the water in the upper part of the brook was 5,8

The pH value in the water in the lower part of the brook was 6,3

The water tests were taken by the first and the second line.

Garbage and waste in the brook: There is little waste, and garbage in the brook. (Class 2)

Conclution:

Therefore we classified the brook as a second class, according to the form.
That means that the brook is moderatly polluted.

Written by Trond, Thomas, Henrik, and Kenneth.