engleski

Highway Runoff Treatment in Croatia

In the Republic of Croatia at the beginning of the 80's, special technical requirements on highway drainage for the purpose of environmental protection against harmful effects of polluted runoff were introduced. These special requirements are valid for the zones of potable water resources protection, and in ecologically sensitive areas such as nature parks, potential potable water resources, and in ecologically valuable areas with unfavourable geological structure. Protection measures are predicted for normal exploitation and accidental situations (large spills of hydrocarbons from trucks). According to the practice applied so far, the environmental protection in that field involves the use of either an open or closed highway drainage system at the end of which there is an oil/grit separator (OGS). Additional protection is achieved trough special construction details the purpose of which is the safety against vehicle skidding from the traffic lane. However, in the karst regions such protection is not sufficient due to high permeability of karst, low capacity of self purification, and practical impossibility of any subsequent action. It is therefore necessary to treat additionally the highway runoff before its final disposal. The paper deals with law regulations and technical practice in highway runoff. Hydrological, ecological, technological, economical and other issues that influence decision-making are also analyzed.

highway drainage; environment; protection; polluted runoff; oil/grit separator; karst

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