Low cost Latrine OptionsLow cost Latrine OptionsLow cost Latrine Options Low cost Latrine Options for for 

Difficult AreaDifficult Area

Engr Mohammad AliEngr. Mohammad AliProject Engineer

Decentralized Total Sanitation Project (Dishari)A project of Dhaka Ahsania Mission

Implemented with joint support ofPlan Bangladesh, WaterAid Bangladesh and WSP-World Bank

Low cost Latrine Option in Plane Land   Low cost Latrine Option in Plane Land   

Ventilated Offset Latrine (Pan with PVC or Gutter)Ventilated Offset Latrine (Pan with PVC or Gutter)( )( )

Estimated Cost: Tk 435-535Durability: 5 members , 3-4 years

Ventilated Offset Latrine (Plastic Pan and Ventilated Offset Latrine (Plastic Pan and BendpipeBendpipe))(( p pp p ))

Estimated Cost: Tk 510-610 Durability: 5 members , 3-4 years

Offset Latrine (Plastic Pan with Siphon)Offset Latrine (Plastic Pan with Siphon)( p )( p )

Estimated Cost: Tk 475-575 Durability: 5 members , 3-4 years

Direct Pit Latrine (Plastic Pan , Water seal, Slab, Ring )Direct Pit Latrine (Plastic Pan , Water seal, Slab, Ring )

Estimated Cost: Tk 595-900 Durability: 5 members , 3-4 years

Latrine for Char/ Coastal/ Flood prone areaLatrine for Char/ Coastal/ Flood prone areaLatrine for Char/ Coastal/ Flood prone area Latrine for Char/ Coastal/ Flood prone area where Water Table is Highwhere Water Table is High

Latrine in Low land areasRaised Pit Latrine (RPL)( )Offset Pit Latrine: 4 optionDirect Pit Latrine: 2 option

Latrine in High land areasSemi Raised Pit Latrine (SRPL)Offset Pit Latrine: 2 optionDirect Pit Latrine: 2 option

Latrine in High land slum areasTwin pit Latrine: 2 option

Direct Pit Latrine: 2 option

Twin pit Latrine: 2 option

Latrine in Low land areasLatrine in Low land areas

Raised Pit Latrine (RPL)Raised Pit Latrine (RPL)

Offset Pit LatrineOffset Pit Latrine

Option  1:  Option  1:  WatersealWaterseal offset pit latrineoffset pit latrine

Materials required:Plastic pan, Water seal, 4” dia PVC pipe, RCC ring, RCC slab, Polythene and p p p g ybamboo.Estimated Cost: Tk1030

Option  2: Ventilated offset pit latrineOption  2: Ventilated offset pit latrine

Materials required: Plastic pan Bend pipe 4” dia PVC pipe 1 5 dia PVC pipe RCC ring RCC slabPlastic pan, Bend pipe, 4 dia PVC pipe, 1.5 dia PVC pipe, RCC ring, RCC slab, Polythene and bamboo.Estimated Cost: Tk 1075

Option 3:Option 3: WatersealWaterseal offset pit latrineoffset pit latrine bamboo liningbamboo liningOption  3:Option  3: WatersealWaterseal offset pit latrineoffset pit latrine‐‐ bamboo liningbamboo lining

Materials required:Plastic pan, Bend pipe, 4” dia PVC pipe, 1.5 dia PVC pipe, RCC ring, RCC slab, Polytheneand bamboo.Estimated Cost: Tk 975Estimated Cost: Tk 975

Option  4:  Ventilated offset pit latrineOption  4:  Ventilated offset pit latrine‐‐ Bamboo liningBamboo lining

Materials required: Plastic pan, Bend pipe, 4” dia PVC pipe, 1.5 dia PVC pipe, RCC ring, RCC slab,Plastic pan, Bend pipe, 4 dia PVC pipe, 1.5 dia PVC pipe, RCC ring, RCC slab, Polythene and bamboo.Estimated Cost: Tk 925

Latrine in Low land areasLatrine in Low land areas

Raised Pit Latrine (RPL)Raised Pit Latrine (RPL)

Direct Pit LatrineDirect Pit Latrine

Option  5: Option  5: Water seal Direct Pit LatrineWater seal Direct Pit Latrine‐‐sand envelop  sand envelop  pp pp

Materials required: RCC ring, RCC slab with pan, Polythene paper, gooseneck and bamboo.Estimated Cost : Tk 950

Option 6:  Water seal direct pit latrineOption 6:  Water seal direct pit latrine

Materials required:qRCC ring, RCC slab with pan, Polythene paper, gooseneck and bamboo.Estimated Cost: Tk 175

Latrine in high land  areasLatrine in high land  areasgg

Semi Raised  Pit Latrine (SRPL)Semi Raised  Pit Latrine (SRPL)

Offset Pit LatrineOffset Pit Latrine

Option 1:  Water seal offset pit latrine bamboo liningOption 1:  Water seal offset pit latrine bamboo lining

Materials required:Materials required:Plastic pan, Water seal, 4” dia PVC pipe, bamboo and fertilizer bag.Estimated Cost : Tk 625

Option 2: Ventilated offset pit latrine Bamboo liningOption 2: Ventilated offset pit latrine Bamboo lining

Materials required:Plastic pan Bend pipe 4” dia PVC pipe 1 5 dia PVC pipe Polythene and bambooPlastic pan, Bend pipe, 4” dia PVC pipe, 1.5 dia PVC pipe, Polythene and bamboo.Estimated Cost: Tk 670

Latrine in high land  areasLatrine in high land  areasgg

Semi Raised  Pit Latrine (SRPL)Semi Raised  Pit Latrine (SRPL)

Direct Pit LatrineDirect Pit Latrine

Option 3: One ring slab water seal direct pit latrineOption 3: One ring slab water seal direct pit latrinep g pp g p

Materials required:RCC ring, RCC slab with pan, Polythene paper, gooseneck and bamboo.Estimated Cost: Tk 605

Option 4:  Water seal direct pit latrineOption 4:  Water seal direct pit latrine

Materials required:qRCC ring, RCC slab with pan, Polythene paper, gooseneck and bamboo.Estimated Cost : Tk 730

Latrine in high land char slum areasLatrine in high land char slum areas

Shared Offset Pit Latrine (SOPL)Shared Offset Pit Latrine (SOPL)

Option 1: Community based twin pit latrineOption 1: Community based twin pit latrine

Materials required:RCC i RCC l b B i k C t P Ti B bRCC ring, RCC slab, Brick, Cement, Pan, Tin, Bamboo.Estimated Cost: Tk 6390 

Option 2: Community based Twin pit ventilated offset pit Option 2: Community based Twin pit ventilated offset pit latrinelatrinelatrinelatrine

Materials required:RCC ring RCC slab Pan Tin BambooRCC ring, RCC slab, Pan, Tin, Bamboo.Estimated Cost: Tk 5930

Site selection criteriaSite selection criteria

Sh ld b d d f f t t t d i i•Should be dry and free from water stagnant during rainy season.•Should be selected 10 meter away from any water sources•Easy access.•Sufficient space.•Water supply is available.•Safe for all.•Should consider condition of soil characteristics, land erosion and

flood level

Design ParametersDesign Parameters

The principal parameters to be considered in selection asuitable type of latrine for a specific community are based on

•soil characteristics•ground water conditions•nature and extent of flooding•nature and extent of flooding,•sources of drinking water and•socioeconomic conditions of the community.

Technical AspectsTechnical Aspects

Soil characteristicsSoil properties of a specific site such as•composition,•porosity and•porosity and•fineness

Soil properties are related to•the stability of pit,•capacity of latrine and•ground water pollution.

Pit Stability•Soil condition•Mixture of clay and sand is the suitable•If the soil is mostly sandy, pit caving in, particularly during the rainy season.

Technical AspectsTechnical Aspects

Capacity of Pit• liquid portion of the excreta percolates into the nearby soil. • Depends on the subsoil permeability.

Soil Type Infiltration Capacity (sewage),l/m2.dyp p y ( g ), /

Sands (e.s.>0.05mm) 50

Silts and loans (e.s. 0.002‐.005 mm) 30

Cl ( 0 002 ) 10Clays(e.s.<0.002mm) <10

Ground water Pollution• Ground water pollution largely depends on soil conditions. Bacteria do not penetrate more than 1 2 metres in most unsaturated soils•Bacteria do not penetrate more than 1-2 metres in most unsaturated soils,

Groundwater conditions• Reduced capacity of the pit•Groundwater contamination•Groundwater contamination.

Technical AspectsTechnical Aspects

FloodingProblems of latrine flooding arei) degradation of environment and the pit is submerged and excreta comes outi) degradation of environment and the pit is submerged and excreta comes out with flood water,ii) people lose sanitation facilities during flood period andiii) latrine get filled wilt silts whish renders them unusable and people may

t t d f ti d th h i i tiresort to open defecation and other unhygienic practices.

Availability of water •when choosing a sanitation options•when choosing a sanitation options. •Maintenance of latrine .