- Name of measurement site: Teuronjoki
- Location: Hausjärvi, Mommila
- Catchment area : Teuronjoki drainage basin, (438 km2)
- Coordinates (ETRS-TM35FIN): P:6748311, I: 394846
Teuronjoki drainage basin consists of Pääjärvi drainage basin (220 km2) and Teuronjoki sub-catchment (> 460 km2). Agricultural fields comprise 23% of the total drainage basin The highest elevation can be found from Evo forest area where ground level is >180 m a.s.l. The elevation of Lake Pääjärvi is 102 m and Mommilanjärvi in the lowermost part 82.5 m a.s.l. The measurement point is situated 1.5 km upstream from lake Mommilanjärvi. Equally with Koiransuolenoja and Löytynoja sub-catchments the soils consist of clayey silt, sandy gravels, moraine and organic soils. Fields situated close to the stream are of fine soil material. Two wastewater treatment plants are located downstream from Lake Pääjärvi in Hämeenkoski and in Kärkölä. Treated wastewaters are discharged into Teuronjoki river. On-line measurements were started in December 2013, and since then also reference samples for water chemistry analyses have been collected year-round.