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Hurricanes and extreme stormwater events can transport fecal contaminants and a wide range of bacterial pathogens to receiving rivers and streams, threatening public health. This study investigated the impact of flooding on bacterial diversity and the occurrence of fecal and potential bacterial pathogens in Texas Rivers over a short (3 weeks and 3 months) and long time (12 months) after Hurricane Harvey. Water samples were collected from 8 sampling sites of Guadalupe and San Antonio Rivers during three sampling events and bacterial community structure was evaluated using next-generation sequencing (NGS). Results showed that Proteobacteria, Actinobacteria, Bacteroidetes, and Cyanobacteria were the predominant phyla in the water samples. Hierarchal cluster analysis and principal coordinate analysis indicated that bacterial community structure was significantly different in the water samples collected from flooded and non-flooded sites. At genus level, eight fecal-associated and twelve potentially pathogenic bacterial genera were detected in water samples, mainly from flooded sites collected during short-term sampling events. Overall, results suggest that NGS-based microbial water quality monitoring of environmental samples after flooding events could provide critical information about the wide range of pathogens, which can be further assessed by specific methods to identify the risk of exposure.

Walking, cycling, and feeder bus/tram for first- and last-mile (FLM) train access are often considered to have better health benefits, lower cost, and less environmental impacts than driving. However, little is known about the road safety impacts of these FLM access modes, particularly at a network level. This paper aims to investigate the impacts of train commuters’ access modes on road safety in Victoria, Australia. Macroscopic analyses of crash outcomes in each zone (i.e., Statistical Area Level 1) were performed using negative binomial (NB) and spatially lagged X negative binomial (SLXNB), accounting for potential indirect effects of mode shares in adjacent zones. This macroscopic analysis approach enabled the consideration of the safety effects across the network. The results showed that the SLXNB models outperformed the NB models. Commuting by train, either with walking or car as FLM access mode, was negatively associated with both total and severe crashes. In addition, commuting by train with feeder bus/tram access mode was negatively associated with severe crashes. Interestingly, commuting by train with cycling access mode was negatively associated with total crashes, with a larger effect when compared to walking and car access modes. Overall, the results suggested promoting active transport as FLM train access mode would lead to an improvement in road safety.