Blue-Green Infrastructure (BGI) consists of natural and semi-natural systems implemented to mitigate climate change impacts in urban areas, including elevated air temperatures and flooding. This study is a state-of-the-art review that presents recent research on BGI by identifying and critically evaluating published studies that considered urban heat island mitigation and stormwater management as potential benefits. Thirty-two records were included in the review, with the majority of studies published after 2015. Findings indicate that BGI effectively controls urban runoff and mitigates urban heat, with the literature being slightly more focused on stormwater management than urban heat island mitigation. Among BGI, the studies on blue- and blue-green roofs focused on one benefit at a time (i.e. thermal or hydrologic performance) and did not consider promoting multiple benefits simultaneously. Two-thirds of the selected studies were performed on a large urban scale, with computer modelling and sensor monitoring being the predominant assessment methods. Compared with typical Green Infrastructure (GI), and from a design perspective, many crucial questions on BGI performance, particularly on smaller urban scales, remain unanswered. Future research will have to continue to explore the performance of BGI, considering the identified gaps.

Stormwater management has focused increasingly on Low Impact Development (LID) techniques in recent years. Although their effectiveness has been demonstrated in a number of cases, methodologies for the selection of most appropriate solutions for individual sites are still evolving. The cost efficiency of implementing a wide range of LID techniques in a proposed land development in the City of London, Ontario, Canada was investigated using continuous hydrologic simulation and a recently developed LID costing tool. The results indicate that infiltration trench and infiltration trench in combination with green roof were the most cost efficient solutions for runoff reduction

Water reclamation implementation and management practices at municipal wastewater treatment plants throughout the world are reviewed and some implementation and operational issues are defined. The information is based on a conventional literature survey, on an in depth survey study of European, Israeli and Australian medium and large-scale water reclamation utilities and on the findings of a dedicated international workshop. The review identified over 3,300 water reclamation projects and designed the map of the main process technologies and their fields of product water application. The main conclusion of the enquiry is that the technological risks no longer represent a major concern for the development of water reclamation projects, rather issues such as the financing, failure management and social acceptance have become more critical.

Inappropriate disposal of wipes and other products that are either explicitly labelled or assumed by the consumers to be flushable via toilets is increasingly being cited as the cause of a range of sewer systems issues. In the rapidly growing and diverse market for these consumer products, there are significant variations in consumer information provided by manufacturers, product composition and behaviour in different components of wastewater system. This paper summarizes the results of assessing the labelling, drainline clearance and disintegration testing of 101 consumer products, adopting the International Water Services Flushability Group flushability specifications. None of the products tested satisfy the product labelling Code of Practice, and all products other than bathroom tissue failed the disintegration test, including the 23 products that were labelled ‘flushable’. The need for a global definition of a ‘flushable’ product exists and it is vital that it is brought into legislation in an effort to combat misconceptions around consumer products that may exist internationally.