The percentage of impervious surfaces in the drainage area or watersheds is correlated with the ow caused by rain in the pumping stations and with water pollution, represented by the conductivity and total concentration of metals.
Fylgni er milli hlutfalls þétts y rborðs á afrennslissvæðum og rennslis af völdum rigningar í dælustöðvum annars vegar, og vatnsmengunar (leiðni og heildarstyrk málma) hins vegar.