Pereira S P, Rosman P C C, Alvarez C, Schetini C A F, Souza R O, Vieira R H S F
Company of Water and Wastewater of Ceará (CAGECE)/Federal University of Ceará (UFC), Rua Tomás Lopes 85, Fortaleza, Ceará, Brazil E-mail:
Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil.
Water Sci Technol. 2015;72(6):928-36. doi: 10.2166/wst.2015.292.
An important tool in environmental management projects and studies due to the complexity of environmental systems, environmental modeling makes it possible to integrate many variables and processes, thereby providing a dynamic view of systems. In this study the bacteriological quality of the coastal waters of Fortaleza (a state capital in Northeastern Brazil) was modeled considering multiple contamination sources. Using the software SisBaHiA, the dispersion of thermotolerant coliforms and Escherichia coli from three sources of contamination (local rivers, storm drains and submarine outfall) was analyzed. The models took into account variations in bacterial decay due to solar radiation and other environmental factors. Fecal pollution discharged from rivers and storm drains is transported westward by coastal currents, contaminating strips of beach water to the left of each storm drain or river. Exception to this condition only occurs on beaches protected by the breakwater of the harbor, where counterclockwise vortexes reverse this behavior. The results of the models were consistent with field measurements taken during the dry and the rainy season. Our results show that the submarine outfall plume was over 2 km from the nearest beach. The storm drains and the Maceió stream are the main factors responsible for the poor water quality on the waterfront of Fortaleza. The depollution of these sources would generate considerable social, health and economic gains for the region.
由于环境系统的复杂性，环境建模在环境管理项目和研究中是一种重要工具，它能够整合众多变量和过程，从而提供系统的动态视图。在本研究中，考虑到多个污染源，对福塔莱萨（巴西东北部的一个州首府）沿海水域的细菌学质量进行了建模。使用SisBaHiA软件，分析了来自三个污染源（当地河流、雨水排放口和海底排污口）的耐热大肠菌群和大肠杆菌的扩散情况。这些模型考虑了由于太阳辐射和其他环境因素导致的细菌衰减变化。从河流和雨水排放口排放的粪便污染通过沿岸海流向西输送，污染了每个雨水排放口或河流左侧的海滩水域条带。只有在港口防波堤保护的海滩上才会出现这种情况的例外，在那里逆时针漩涡会使这种行为逆转。模型结果与旱季和雨季期间的实地测量结果一致。我们的结果表明，海底排污口羽流距离最近的海滩超过2公里。雨水排放口和马塞约河是造成福塔莱萨滨水区水质不佳的主要因素。对这些污染源进行污染治理将为该地区带来可观的社会、健康和经济效益。
