Removal of non-point source pollutants from domestic sewage and agricultural runoff by eco/vegetated drainage ditches (VDDs): Design, mechanism, management strategies, and future directions

Authors: MATHIEU, NSENGA KUMWIMBA - Sun Yat-Sen University; MENG, FANGANG - Sun Yat-Sen University; ISEYEMI, OLUWAYINKA - US Department Of Agriculture (USDA); Moore, Matthew; ZHU, BO - Chinese Academy Of Sciences; TAO, WANG - Chinese Academy Of Sciences; LIANG, TANG - Chinese Academy Of Sciences; ILUNGA, LUNDA - Université De Lorraine

Submitted to: Water Research
Publication Type: Review Article
Publication Acceptance Date: 5/15/2018
Publication Date: 5/18/2018
Publication URL: https://handle.nal.usda.gov/10113/5979940
Citation: Mathieu, N., Meng, F., Iseyemi, O.O., Moore, M.T., Zhu, B., Tao, W., Liang, T.J., Ilunga, L. 2018. Removal of non-point source pollutants from domestic sewage and agricultural runoff by eco/vegetated drainage ditches (VDDs): Design, mechanism, management strategies, and future directions. Water Research. 639:742-759. https://doi.org/10.1016/j.scitotenv.2018.05.184.
DOI: https://doi.org/10.1016/j.scitotenv.2018.05.184

Interpretive Summary: Agricultural runoff impacts rivers, lakes, and streams on a global scale, while in developing countries, domestic sewage is often an additional source of pollution. The use of vegetated drainage ditches to mitigate the variety of pollutants found in agricultural runoff and domestic sewage is an economical and environmentally efficient method for water quality improvement. This review examines the various designs and critical mechanisms for contaminant degradation employed by vegetated drainage ditches. Future directions and importance of this relatively new management practice on the landscape level are also addressed.

Technical Abstract: Domestic wastewater and agricultural runoff are increasingly viewed as major threats to both aquatic and terrestrial ecosystems due to the introduction of non-point source pollutants (e.g., nitrogen, phosphorus and metals) and organic pollutants (e.g., pesticides and pharmaceutical residues). With rapid economic growth and social change in rural regions, it is important to examine the treatment systems in rural and remote areas for high efficiency, low running costs, and minimal maintenance in order to minimize its influence on water bodies and biodiversity. Recently, the use of ecological/vegetated drainage ditches (VDDs) has been employed in treatment of domestic sewage and agricultural runoff, but information on the performance of VDDs for treating these pollutants with various new management practices is still not sufficiently summarized. This paper aims to outline and review current knowledge related to the use of VDDs in mitigating these pollutants from domestic sewage and agricultural runoff. Literature analysis has suggested that further research should be carried out to improve ditch characteristics and management strategies inside ditches in order to ensure their effectiveness. Firstly, the reported major ditch characteristics with the most effect on pollutant removal processes (e.g., plant species, weirs, biofilms, and substrates selection) were summarized. The second focus concerns the function of ditch characteristics in VDDs for pollutant removal and identification of possible removal mechanisms involved. Thirdly, we examined factors to consider for establishing appropriate management strategies within ditches and how these could influence the whole ditch design process. The current review promotes areas where future research is needed and highlights clear and sufficient evidence regarding performance and application of this overlooked ditch system to reduce pollutants.