- give the amount of pollutants and other chemical components leaving
the catchment through the stream
- together with results from the deposition programmes establish
chemical input/output balances for the catchment
Runoff water contains the main output of solutes from a catchment
area. A runoff water gauge is installed in a small dam at the
lowest part of the central stream. The output is calculated by
continually measuring the runoff water volume at the discharge
point and analysing the concentrations of chemicals in the water.
Water is sampled twice a month for chemical analysis.
- normal year: pH, conductivity, Na, K, Ca, Mg, Al, Mn, Fe, NH4, NO3, SO4, Cl, HCO3, total N and total C, volume of discharged water
- campaign year additionally: Cu, Zn, Pb, Cd, Hg, methyl-Hg and