Updated database v. 2018-02-26 26 February, 20188 September, 2021 New data of zinc surfaces and copper surfaces, e.g. copper facades or roofs, zinc rails or roofs, which can be calculated in StormTac Web by using the land use “Own”, see Guide Description of land uses 2018-02-26. Updated flow detention functions in serial facilities Updated concentrations for phosphorus, nitrogen and benzo(a)pyrene from woodland, farmland and other open land uses