- Name of measurement site: Löytynoja
- Location: Hämeenlinna, Lammi, Pappilakylä
- Catchment area: Lammin Pääjärvi, Koiransuolenoja sub-catchment (6.2 km2)
- Catchment area: Lammin Pääjärvi, Löytynoja sub-catchment (8.0 km2)
- Coordinates (ETRS-TM35FIN): P:6768939, I: 393330
Löytynoja catchment is the second smallest among the Pääjärvi dranage basin. Agricultural lands comprise 17% of the catchment, and peatlands 14%. A large proportion of peat bogs were drained between 1960-1970. An esker is situated in the middle of the catchment, and it covers >60% the total area. Forestry is the dominant land-use like in all sub-catchments of lake Pääjärvi. Soils are formed from clayey silt, sandy gravels, moraine and organic soils. Fields situated close to the stream are of fine soil material. The length of Löytynoja stream is 4.4 km. It flows beneath Highway 12 towards the lake. The measurement point is situated 0.4 km upstream from lake Pääjärvi. On-line measurements were started in 2016, and weekly samples for water chemistry have been collected since 1991 during the open water season and since 2000 year-round.