Abstract：
The Kereh River in Penang, Malaysia, has faced severe pollution for over 40 years due to untreated wastewater from swine farms in Kampung Selamat, discharged via stormwater drains. Despite official claims that all 77 swine farms treat their wastewater to meet regulatory standards, local non-governmental organizations and villagers have challenged this, though their concerns lack scientific backing. This study evaluates the river\'s water quality by analyzing samples from upstream (US), midstream (MS), and downstream (DS), and from Parit Cina-Parit Besar, a conduit for untreated swine wastewater. Fourteen parameters were measured against Malaysia\'s National Water Quality Standards (NWQS). Significant differences were found in six parameters: ammonium nitrogen (AN), biochemical oxygen demand (BOD), chemical oxygen demand (COD), dissolved oxygen (DO), total suspended solids (TSS), and oil and grease (OG). While Dunn\'s post hoc pairwise comparison showed no significant differences among river segments, mean values indicated increased pollution downstream, particularly after the convergence with untreated swine wastewater. River classification worsened, with water quality index dropping from 69.88 ± 11.37 score (Class III) US to 38.49 ± 12.74 and 50.44 ± 3.14 scores (Class IV) MS and downstream, respectively. A significant positive correlation between E. coli and AN (r = 0.71, p < 0.01) suggests a common point source pollutant, particularly the untreated swine wastewater. The river exhibits low oxygen levels and high organic matter and nutrient concentrations, especially MS and downstream, highlighting substantial ecological and public health risks. Effective enforcement of waste treatment regulations and enhanced monitoring are crucial for mitigating pollution and restoring the river\'s ecosystem. Collaboration between authorities and pig farmers is essential to improve water quality and maintain the river\'s ecological balance. PRACTITIONER POINTS: Severe Kereh River pollution: Untreated swine wastewater from Kampung Selamat pig farms, primarily via Parit Cina-Parit Besar, has degraded the river for over 40 years. Regulatory non-compliance: Despite official claims, untreated swine wastewater continues to pollute the river, challenging regulatory standards. Significant pollution indicators: Elevated levels of AN, BOD, COD, DO, TSS, OG, and E. coli signal severe pollution midstream and downstream. Water quality index drop: WQI scores classify midstream and downstream sections as polluted, indicating worsening conditions downstream. Urgent need for action: Enforcing regulations, improving wastewater treatment, and relocating pig farms are crucial for restoring the Kereh River.
摘要：
槟城的Kereh河,马来西亚,由于KampungSelamat养猪场未经处理的废水，40多年来一直面临严重的污染，通过雨水排放。尽管官方声称所有77个猪场都处理废水以符合监管标准，当地非政府组织和村民对此提出了挑战，尽管他们的担忧缺乏科学支持。这项研究通过分析上游(美国)的样本来评估河流的水质，中游（MS），和下游(DS)，来自ParitCina-ParitBesar,用于处理未经处理的猪废水的管道。根据马来西亚国家水质标准(NWQS)测量了14个参数。在六个参数中发现了显着差异：铵态氮（AN），生化需氧量（BOD），化学需氧量(COD),溶解氧（DO），总悬浮固体（TSS），和油和润滑脂（OG）。虽然邓恩的事后成对比较显示河流段之间没有显著差异，平均值表明下游污染增加，特别是在与未经处理的猪废水汇合之后。河流分类恶化，水质指数从69.88±11.37分（III级）下降到38.49±12.74和50.44±3.14分（IV级）MS和下游，分别。大肠杆菌和AN之间的显著正相关(r=0.71,p<0.01)表明是一个共同的点源污染物,特别是未经处理的猪废水。河流的氧气含量低，有机物和养分浓度高，特别是MS和下游，强调重大的生态和公共卫生风险。有效执行废物处理法规和加强监测对于减轻污染和恢复河流生态系统至关重要。当局与养猪户之间的合作对于改善水质和维持河流的生态平衡至关重要。实践要点：严重的Kereh河污染：KampungSelamat养猪场未经处理的猪废水，主要通过ParitCina-ParitBesar,这条河流已经退化了40多年。监管不合规：尽管官方声称，未经处理的猪废水继续污染河流，具有挑战性的监管标准。重要的污染指标：AN水平升高，BOD,COD,CODDO,TSS,OG,大肠杆菌发出中下游严重污染的信号。水质指数下降：WQI评分将中游和下游路段分类为污染，表明下游条件恶化。迫切需要采取行动：执行法规，改善废水处理，重新安置养猪场对于恢复凯瑞河至关重要。
