UTSLÄPP AV FOSFOR OCH KVÄVE VIA DAGVATTEN FRÅN TÄTORTER Exempel från Mjölby vid Svartån / Discharge of Phosphorus and Nitrogen with Storm Water
The result of a part of the studies of the transport of nitrogen and phosphorus to the Svartå river within the Motala Ström river basin is given. The amount of nutrients transported to the river with the storm water from the city of Mjölby has been estimated.
By maps and field investigations the size of contributing areas has been determined to 160 ha approximately, which causes a storm water volume of 800×103 m3/year normally. The total amount of phosphorus and nitrogen discharged with the storm water has been estimated to 0.24 ton/year and 1.6 ton/year respectively assuming a concentration of phosphorus of 0.3 mg/1 and a concentration of nitrogen of 2.0 mg/1. In 1984 the discharge of nutrients with the treated sewage water was 1.5ton phosphorus and 55ton nitrogen. The estimations can be improved after water sampling, water analysis, and flow measurements. “Complete abstract not presented.”