Informal settlements suffer health issues due to inadequate toilet facilities and unsafe faecal sludge management (FSM). In addition to the people's unsafe management, sweepers provided emptying services informally with unsafe methods, and authorities adopted city-wide vacutug-based services where informal settlements are excluded. This paper explores factors causing unsafe FSM and develops a contextual model that includes informal settlements with environmentally safe city-wide services. It took Notun-Bazar Char Khulna as a case, and purposefully sampled toilets, settlement people, sweepers, and key persons for interview and group discussions. These responses located some existing sanitation intervention factors responsible for unsafe containment, emptying, conveyance, and discharge practice. This paper proposes equitable, impenetrable, and emptiable containment, periodical emptying and conveyance, adaptive equipment, adaptive health safety kit, and proximal safe discharge location as components of a context-sensitive model to include informal settlements with a city-wide environmentally safe FSM system.

Informal settlements suffer sanitation challenges of inadequate toilet facilities and a high accumulation rate of faecal sludge due to land crises and dense populations. However, settlement people who struggle with informal living, either way, manage to keep their toilets running. This research explores faecal sludge management practices by people in informal settlements. It took Notun-Bazar Char Khulna as a case, purposefully sampled toilets, and populations, and conducted interviews and group discussions among settlement people, sweepers, key persons, and detailed observations of settlement premises. It also mapped excreta flows and discharge locations in drawings and diagrams. It illustrates how faecal sludge from all types of containment ending in the water is unsafe. This study analytically finds practices related to periodical containment management, Collective emptying mechanism, and faecal sludge’s conditional conveyance available in the informal settlement. It suggests developing environmentally safe faecal sludge management in informal settlements with an appreciation of the identified practices.

The urban wastewater management system is one of the most important infrastructures for an urban residential area and any kind of infrastructure has some spatial considerations. The conventional centralized wastewater management system is an enormous structure that generally fails to address the needs of residential areas for the collection and disposal of domestic wastewater from on-site sanitation. The decentralized management system is a promising but challenging option due to its spatial aspect i.e., specific areas required for implementation. This paper explores the grounds of wastewater mismanagement associated with the spatial aspects. For this purpose, research has performed a spatial analysis of Khalishpur, a residential area of Khulna city of Bangladesh. Two sample tissues in ward 12 were selected based on diverse spatial configurations. The study was led through an area survey, local people’s interviews, and Key Informant Interviews. Several maps, sections, and supporting drawings were developed based on the survey data to explicate the problems of wastewater management systems influenced by spatial aspects. Finally, this research has tried to find out the indicators of wastewater mismanagement aligned by spatial features. That will be helpful for the authority of area planning and wastewater management in combined to develop a wastewater management system focusing on the spatial aspects.

The roof of the building needs insulation for thermal and humidity purposes. In Bangladesh lime-terracing is used for this purpose. Mortar made of slaked lime and powdered brick (local name: surki) is applied on the reinforced roof in 100 mm layer.  It works fairly well in the situation where the variation of internal and external temperatures is low. In Bangladesh this variation in the naturally ventilated rooms is not over 3○ C and lime terracing shows a time lag of about 5 hours at this range. Some of the problems of the conventional Lime terracing are (a) It is costly, (b) It allows heat leakage when atmospheric temperature rises above 35○ Celsius and also when there is wide variation in internal and external temperatures due to air-conditioning of the room. The authors of this paper devised an alternate system. In this system air pockets were provided inside the layer such that it became lighter, consumed less material and had more insulating properties. The air pockets were provided by using burnt clay pots available in the market. The system was named Burnt-Pot Roof Insulation, abbreviated as BPRI. It was first applied in Khulna, Bangladesh in the year 2002. The cost of construction was only 10% of the cost of conventional lime terracing. The system at present is having increasing use in the country.

Salinity has been considered as one of the major problems for building all over the world. The effect of salinity can be observed through the presence of dampness in building materials. Buildings in the coastal regions of Bangladesh are facing serious problems with dampness. Raised sub-soil water level and the presence of higher percentage of salinity in ground water are the common phenomena in this region. The building materials available in this region also contain higher percentage of salinity, which causes deterioration of the building materials. Khulna, one of the largest cities in Bangladesh is facing this problem. In recent years the sub-soil water level and saline intrusion into the soil has been increasing gradually. These factors are causing huge wastage of money yearly for protecting the buildings from dampness. Different attempts have been taken at the government and private levels for the prevention of dampness in structures. It has been observed that the conventional methods cannot cope with the increasing rate of the dampness. A proper research is very much needed to find out a sustainable solution and strategy to check dampness in the buildings. In doing this, it is important to find out the reasons for dampness and its magnitude so that the effective preventive measures may be taken. This paper intends to identify the source, distribution and magnitude of dampness in building materials in coastal regions of Bangladesh.