Associated Risks
Source of disease
◦ Unsafe disposal faeces can lead to the
contamination of ground and water sources
◦ Provide breeding sites for flies which may
carry infection
Transmission of disease
◦ Excreta-relates diseases is largely faecal-oral
High-risk groups
◦ Children under five years of age are most at
risk from communicable disease
Health hazards of improper
excreta disposal
Soil pollution
Water pollution
Contamination of foods
Propagation of flies
Transmission of disease from faeces
Sanitation Barrier
Criteria for a sanitary latrine
Excreta should not contaminate the
ground and surface water
Excreta should not pollute the soil
Excreta should not be accessible to flies,
rodents, animal
Excreta should not create a nuisance due
to odor or unsightly apperance
Technologies for excreta disposal
Cartage (Conservancy system)
◦ Example: Bucket latrine
◦ Disadvantages
Smell
Flies
Health risk to people
handling the excreta
Health risk from food crops
fertilized with raw excreta
Pit latrines
Pit latrine is a type
of toilet that collects
human feces in a hole in
the ground
Faecal matter is stored
in a pit and left to
decompose.
Unless specifically
designed
Pit latrines
Bad practice
Pit latrines
Advantages of pit latrines may
include:
Can be built and repaired with locally
available materials
Low (but variable) capital costs depending
on materials and pit depth
Small land area required
Pit latrines
Disadvantages of pit latrines may
include
◦ Flies and odors
◦ Low reduction in organic matter content and
pathogens
◦ Possible contamination of ground water with
pathogens and nitrate
◦ Pit latrines are often relocated or re-built
after some years
Simple pit latrine
Simple pit latrines
The simple pit latrine
is cheapest and most
basic form of
improved sanitation
available
Pour-flush pit latrine
Septic tank latrines
A septic tank consists of one or more
concrete or plastic tanks
Septic tank latrines
A septic tank is a form of on-site
sanitation that provides the convenience
of a sewerage system
Each household needs sufficient water to
flush faeces into septic tank efficiency
Generally, the removal of 50% of solids, 30
to 40% of BOD