Prospects and Limitations of Surface Runoff Quality Management in the Republic of Serbia

 Aleksandar Djukić1, Dejan Ljubisavljević1


1 University of Belgrade, Faculty of Civil Engineering, Bul. Kralja Alexandra 73, Belgrade, R. of Serbia; e-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Abstract

The paper gives an overview of methods and procedures for stormwater runoff quality control in urban areas, as well as experiences of various countries. It was estimated that it will take a series of administrative, organisational, technical and research efforts in order to establish efficient and sustainable measures for stormwater control and management in R. of Serbia.

Keywords: stormwater runoff, water quality, water management

 

 

Background

One of most important measures for the reduction of negative environmental impacts of urban wastewater, is wastewater treatment. Wastewater treatment is performed by using different combined treatment processes in order to achieve the required level of treatment, i.e. to remove pollutants to the required levels. There are two basic approaches to determining the required levels of wastewater treatment:

  • Determination of treatment levels based on the required recipient water quality standard. This methodology requires that the recipient maintains a certain water quality after mixing with the treated wastewater.
  • Effluent Standards - determination of the required treatment levels based on defined pollutant limit values in the treated wastewater. The best known example of this approach is the European Commission Council Directive 91/271/EEC, which requires that all urban wastewater from point sources greater than 2000 population equivalents (p.e.) must be treated to the level given in Table 1.

 

Table 1: Requirements for discharges from urban wastewater treatment plants as per Directive 91/271/EEC

Parameter

Maximum concentration in discharge

BOD5

25 mg / l

COD

125 mg / l

Suspended solids (from 2,000 to 10,000 PE)

60 mg / l

Suspended solids (more than 10,000 PE)

35 mg / l

Total nitrogen (from 10,000 to 100,000 ES)

15 mg / l *

Total nitrogen (more than 100,000 ES)

10 mg / l *

Total phosphorus (from 10,000 to 100,000 ES)

2 mg / l

Total phosphorus (more than 100,000 ES)

1 mg / l

* - The average annual

 

The EU Water Framework Directive (WFD), adopted in 2000, introduced a combined approach. The WFD requires prior regulation for point source discharges liable to cause pollution. Controls may include prevention of pollutant entry into water, prior authorisation, or registration based on general binding rules and laying down pollutant emission controls. On the other hand, WFD introduces the ultimate goal of "good ecological and chemical status" for all European waters by 2015. "Good ecological status" is determined by biological, chemical and morphological (physical structure) parameters based on specific river basin management plans.

Values given in Table 1 are related to wastewater generated by residential, institutional, commercial and industrial establishments and are not applicable to stormwater runoff (except for the small portion of runoff that is conveyed to WWTPs through combined sewer systems).