The four Nordic cities included in the present study form a gradient both in climate, from oceanographic temperate in Tórshavn at 620 N to arctic in Tromsø at 69.70N, and in population, from less than 6000 inhabitants in Sisimiut to close to 120 000 in Reykjavík. The cities are different and far apart but products from the sea has been mainstay to the economy and societal development. Thus, the management of sewage from the municipalities must maintain a clean and healthy marine environment. The wastewater treatment varies, from screening on fine mesh, via septic tank based purification solutions, to no purification at all. We measured the contaminants in wastewater streams and in recipient samples, and with that in hand assessed whether the wastewater treatment appeared sufficient, and if not, which mitigating solutions could be relevant for wastewater purification optimisation.