1. GuidelinesforLatrine Site
Selection
Getting the location right is very important in ensuring the use of the facility,
reducing its risk to public health and nuisance to the environment. Right
positioning of the facility away fromadverseenvironmental conditions can
enhance the operational life, e.g. positioning the toilet systemoutsidethe course
of run-off can help prevent the effects of erosion that havebeen witnessed in
some parts of Northern Ghana. In selecting a site for a latrine, the location of
wells and surfacewater sources, for example ponds, swamps, creeks,rivers etc.
must be clearly established. The following guidelines shall be used for the siting of
latrines:
• A latrine mustnot be locatedovera surface waterbodyand shouldbe at least100 feet(30 m) from
the edge of the floodplainof asurface waterbody.
• Publiclatrinesshallbe atleast50 metersfromnearestresidence orasfar as practicable.
• Latrinesshall be sitedawayfromtreestopreventobstructionof ventpipes.
• Latrinesshall be constructedwithenoughspace forvehicle accessandmovementduringdesludging.
• Inthe selectionof soil conditionsonwhichtoconstructthe latrines,avoid(if possible) rockyoutcrops,
unstable groundconditionsand depressionswithshallowwatertable.
• Latrinesshall be constructedwithadequate drainage toensure thatrainwaterdoesnotfloodthe pit.
The CompostingToilet
3. Compostingtoiletinstructions
A possible technologythatcansafelyandefficientlymanage humangeneratedfecesplusconserve
waterand energyisthe compostingtoilet.Unlike flushtoilets,little tonowaterisusedand the fecal
matteris treatednearbythroughthe processof aerobicdecomposition. Withacomposttoilet,the
wastesare not flushedawaybutare recycledbygeneratingthe environmental conditionsneededto
breakdownthe wastesandkill anypathogens.
Composttoiletstructure
The basic componentsof a compostingtoiletare:
1. The compost chamber,where the fecal andcompostingadditive mixtogetherfordecomposition
2. An exhaustsystemtoremove odors,heatandgasesfromthe decompositionprocess
3. Ventilationtoprovide aerationthatwill supportthe growthof aerobicorganisms
4. A wayof managingexcessliquidandleachate (optional)
5. A wayto withdrawthe compost
4. Composttoiletsystem
Generally,composttoiletscanbe dividedintotwodifferenttypes(althoughsome mayuse electricity
othersmay not,some flushwithasmall amountof water andothersuse no water(see Composttoilet
designs(Acrobat(PDF) 324kB Aug15 17))).The firstisthe self-contained toiletandithas a composting
reactor directlyunderneaththe seatwhere the fecesandcompostingmaterial are mixed.Itisone single
unitand the initial compostingoccurswithinit butisrecommendedthatitbe takento a largercompost
pile forfurthertreatment.Inthe central orremote chamberdesignthe toiletrestsabove alarge
compostingreactorwhichcouldbe locatedina basement.The chamberservesasthe central collection
pointand isable to decompose large amountsof fecesfromone orseveral toilets.
Siting and construction of pit latrine with slab
5. It iscommonlymade of concrete and coversthe pitof the latrine.Platformsmayalsobe made of wood
or bamboo.The slabhas a hole initthroughwithto defecate orurinate.
Platformconstructionanddesigninvolvesselectingthe type of slabyouwant.Thismay be a squatting
or a sittingslab.
It will alsoinvolve decidingwhat,if any,improvementsthe pitlatrinewillhave,calculatingthe
dimensionsof the slab,anddeterminingthe materials,labor,andtoolsneededtobuildit.
6. It wouldbe advantageoustodevelopdrawingsandplansforplatformconstruction andany
improvementsalongwithamaterialslist.Theseitemscouldthenbe giventothe individual incharge of
constructingthe pitlatrine.
The type of slabdesignedwill dependonwhetherthe usersprefertositor squat whenusingthe pit
latrine.Believeitornot, some people preferone overthe other.
There are advantagesanddisadvantagestoboth.Basically,itwill come downtothe preferenceof the
users.
Sittingisthe Americanwayandmost of us preferthe comfortand perceivedcivilityof anice toiletseat
as opposedtoan openhole overwhichyousquatto do yourbusiness.
Many people aroundthe worldpreferthe squattingposition.Itisa natural position,afterall thisishow
we poopedbefore we builttoilets.
It may alsobe viewedasbeingmore sanitary,since there isnocontactwitha possiblydirtytoiletseat.
Whateverthe user’spreference,youwill wanttodecide whatthatisand planaccordinglyforpurposes
of pitlatrine platformconstruction.
Sizing of HouseholdLatrines pit
To determine the depthof pitrequired,the total numberof people whowilluse
the facilityandthe desiredoperationperiodisneeded.below indicates
varioushouseholdsizesandbasedonthe desiredoperationperiodpresents
minimumrequireddepths.Pit volumespresentedinthismanual/handbookis
basedon a householdsizeof 10 people anddesignlifeof 8 years.
7. Sample Calculation for Sizing of latrine Pits
Solidsaccumulation
For a householdof 6 persons,inone year,the volume of accumulatedsludge (usingsludge
accumulationrate of 70 litres/capita/year) =6 x 70 litres= 420 litres=0.42 m3
(Thisallowsformaterialsusedforanal cleansing;reducedaerobicanddecompositionoverthe chosen5
yearoperational period).
Usinga basicinternal pit areaof 1.2 m wide x 2.15 m long= 2.58 m2
Resultingdepthof sludge =(0.42 * 5)/2.58 =0.814 m
Free board
Additional safe space above solidtoallow forcoveringwithsoilwhenpitisfull;minimum
free board= 0.3m
Total depthof pit= 0.814 + 0.3 = 1.1 m
