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.

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VEHA - Field Implementation Guidance

Water supply, Sanitation and Hygiene Promotion (WASH)
Construction and material sourcing
Construction activities
Construction of sand filters

Construction of sand filters


Environmental factors causing/contributing to the needs and affecting the humanitarian activity

Sudden or progressive change in the environment adversely affects the lives or living conditions of people who may have been displaced from their origin. When environmental degradation occurs or sudden onset hazards impact vulnerable areas, people may be forced to move and relocate to areas that then require new infrastructure. The new infrastructure should be built to be resilient and strong enough to endure the impact of future natural hazards.

Gender, age, disability and HIV/AIDS implications

Excluded people hold the least power to influence decision-making whilst decisions regarding construction are usually made with people who hold significant relative power. Normally excluded people should be consulted regarding potential environmental impacts and regarding their personal needs and dependencies on the local environment.


Environmental impact categories

Air pollution
Soil pollution
Water pollution
Loss of biodiversity and ecosystems
Natural Resource depletion
Soil erosion

Summary of Impacts
Summary of potential environmental impacts

Riparian erosion due to the extraction of sand (sand mining) for the construction of sand filters.

Damage to sensitive aquatic ecosystems – affecting flora and fauna breeding, oxygen levels, sunlight, water temperature, food chains.

Impact detail
Detailed potential environmental impact information

Instream sand dredging causes substantial destruction of aquatic ecosystems and riparian erosion, by creating large changes in the channel morphology. Impacts include bed degradation, bed coarsening, lowered water tables near the streambed, channel instability, and bank erosion.

Depletion of sand in the streambed and along coastal areas causes the deepening of rivers and estuaries, and the enlargement of river mouths and coastal inlets. It may also lead to saline-water intrusion if it is near to the sea. Dredging can destroy breeding and feeding zones for fish and other aquatic creatures leading to local extinctions.


Summary of environmental activities

Careful site selection.
Seek alternatives to sand.
Seek alternative treatment to sand filtration.
Identify more sustainable/less impactful sand sources.
Control the amounts of sand extracted from river banks.

Detailed guidance for implementing suggested environmental activities

Careful site selection for dredging – assessing the impacts on aquatic ecosystems. Seek alternatives to sand wherever possible e.g. recent technologies reprocessing processing plastics to replace sand in construction, or seek more sustainable/less impactful sources. Control the amounts of sand extracted from river banks. Control the amounts of sand that people extract for the construction of sand filters and verify any changes in the channel morphology. Implement other types of water treatment processes at the household level with a lower impact on the environment.

Lessons Learnt
Lessons from past experiences

Riparian erosion is one of the major causes of sediment and contaminant load to streams, degradation of riparian wildlife habitats, and land loss hazards. Land and soil management practices are implemented as conservation and restoration measures to mitigate the environmental problems brought about by riparian erosion. This, however, requires the identification of vulnerable areas to soil erosion.

Because of the complex interactions between the different mechanisms that govern soil erosion and the inherent uncertainties involved in quantifying these processes, assessing erosion vulnerability at the watershed scale is challenging and requires the use of computer models.

Lessons from Fort Cobb Reservoir Experimental watershed in southcentral Oklahoma can be found here:,habitats%2C%20and%20land%20loss%20hazards.&text=The%20environmental%20features%20used%20as,%2C%20lateral%20inflow%2C%20and%20discharge

Activity Measurement
Environmental indicators/monitoring examples

Extraction of sand from rivers is controlled and limits of extraction are set according to the river properties

Activity status
Main Focus
Focus of suggested activities

Prevention of environmental damage

Resource implications (physical assets, time, effort)

Time, resources and expertise for site selection and sourcing alternative materials.

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