Author(s): Ariel Ali Bento Magalhaes, Jose Rodolfo Scarati Martins, Fábio Paiva Da Silva, Lais Ferrer Amorim

Linked Author(s): Jose Rodolfo Scarati Martins

Keywords: Nonpoint; Pollution; Water quality; Runoff;

Abstract: The excessive use of water capacity, due to problems of availability, high demand and surface water pollution have caused great water stress. However, surface runoff have been identified as the cause of significant impacts on water and the aquatic habitat. Much is known about punctual pollution, which are easy to quantify, predict and their locations are known. Thus, it is essential to develop methods and concepts to quantify the pollutant load present in the superficial flows. The most striking feature of nonpoint pollution is the great variability of the concentration of the pollutants present on the surfaces captured by runoff. Concentrations vary by orders of magnitude between river basins, between different precipitation events, and also over the same event. Nonpoint loads can be quantified and estimated by several methods, such as: Exports Coefficients (EC) or Unit Loads, Event Mean Concentration (EMC) and Mathematical Simulation Models, many others or even combinations, improving reliability. Basically two approaches to model diffuse pollution are identified. The more widely used are lumped-parameter models, while more complex models are based on the distributed-parameter concept. Four models (USGS, HSPF, STORM, SWMM) were described briefly. Finally, it is shown that computer simulation models which accommodate the processes that water undergoes (in terms of quantity and quality) in the upland watershed and downstream waterbodies are highly needed. Techniques available for analysis and prediction of nonpoint source (NPS) pollution loads, concentrations and modeling are reviewed in this paper. This review indicates the need for extensive further research on the subject.

DOI: https://doi.org/10.3850/38WC092019-1683

Year: 2019