VEHA
Guidance
Guidance
Virtual Environmental and Humanitarian Adviser Tool – (VEHA Tool) is a tool
to easily integrate environmental considerations in humanitarian response. Field Implementation guidances are useful for the design and execution of humanitarian activities in the field.
Water pollution can affect people’s health. Bacterial, viral and parasitic diseases like typhoid, cholera, encephalitis, poliomyelitis, hepatitis, skin infection, and gastrointestinal diseases can spread through polluted water increasing the probabilities of overloading the capacity of excreta management systems due to diarrhoeal and vomiting cases. This impacts efficiency and capacity (that is increased amount of excreta generated due to health burdens).
In addition, proximity between water tubewells and latrines, soil porosity, groundwater table, topography, drainage, and stability of slopes, may result in pollution of wells from surface water, sewage, sludge, solid waste leachates, chemical spills, etc and subsequent sickness or disease.
Women often bear cleaning responsibilities and in many cases also are responsible for the disposal of human waste. During menstruation, pregnancy, and postnatal stages the need for adequate sanitation becomes even more critical and Toilet-avoidance dehydration is a particular health threat. Women are acutely aware of safety and privacy issues associated with the need for sanitation. In addition, cultural norms of femininity impose their own demands, for example, in some societies, pregnant women should not be seen in public, and pregnant women are prohibited from using public facilities. In other cultural settings, daughters may not use the same latrine as their fathers or fathers-in-law.
The environmental implications of not considering gender in excreta management activities are related to the pollution of soil and water resources due to improper design of facilities that force women and girls to use other spaces for their needs, but that are not suitable to receive the organic loads and contaminants from human waste.
Open defecation areas can be problematic for small people (e.g. children) and people with disabilities, because of design issues, the need for balance and core strength, difficulty of seeing key features, and potential lack of clean support structures. They often do not offer much privacy for things such as menstruation or cleaning of medical devices.
In addition, given that a lot of foreign items that might block sewage systems may be introduced by women (due to childcare (nappies) or hygiene (menstruation / sanitary towels), the sensitisation messages could be particularly targeted through spaces or structures where women can be most easily accessed. For example, question and answer sessions in meetings of women’s groups or similar.
Soil pollution
Water pollution
Eutrophication
Loss of biodiversity and ecosystems
Water and soil pollution due to the spread of faecal coliforms through soil/ground water.
Emergency pit latrines are an emergency short-term option only. They are usually defined using shallow trench latrines that are in direct contact with the soil. Inadequate management of this type of temporary facility may lead to groundwater pollution due to infiltration of faecal coliforms from raw sewage in the trenches.
Different soil types have different permeabilities (rates of infiltration). Rocky/gravel, sandy or loamy surfaces have higher rates of infiltration, meaning faecal bacteria travel faster through the soil towards groundwater reserves.
Avoid the use of shallow trench latrines wherever possible.
Locate any shallow trench latrines in non-porous soils that are not in direct contact with groundwater or surface water bodies. If this is not possible, provide temporary pit lining using large plastic sheeting or imported clay. Keep pits covered to reduce disease spread and regularly empty them and treat the sludge, or cover and bury the septage if safe to do so.
Open trenches should be avoided wherever possible and replaced with safer alternatives as soon as possible – including ventilated improved pit latrines, septic tanks, and local sewerage networks.
Where used, trenches should always be located downstream of water abstraction points, considerably separated from groundwater, accounting for seasonal variation, because trenches may serve the population for longer than intended, even though trenches are always only an emergency temporary solution.
Ensure that trench latrines are located where the soil is predominantly impermeable or conduct soil compaction or install lining to the base and sides of the trenches in order to minimise sewage infiltration into groundwater. Provide sufficient amounts of soil to cover faeces in the trenches after every use in order to prevent breeding environments for vectors that could spread diseases or contaminate surface water sources. For soils with higher infiltration rates, the trench surfaces should include an artificial impermeable lining or imported clay lining where possible.
When decommissioning shallow trench latrines ensure that collected waste is properly managed and disposed of and is treated following the standards required for the final disposal (including reuse or material for biogas production). After decommissioning, improved facilities should be constructed, which separate human excreta from human contact. Latrines/toilets should have an improved design, e.g. septic systems, slab covered pits, ventilated pits, etc.
Ground water abstraction in Cox’s Bazaar is from tube wells in highly sandy soil. The concentration of so many refugees in an overpopulated area has led to toilets being constructed upstream of tube wells, leading to water pollution from faecal coliforms. More recently, water supply networks have been constructed to supply many of the camps with clean water supplies.
Percentage of open defecation areas located and built considering the protection of ground water sources
Prevention of environmental damage
Soil tests to determine the most suitable locations for trench latrines and to identify areas that allow for soil compaction (include proctor tests, to determine the optimum soil water content and reach maximum compaction possible). If needed, impermeable lining materials. Also, understanding of groundwater flows (having to locate the field downstream of water extraction points)