CONSERVANCY SYSTEMS three presentation (2).ppt

Conservancy and drainage

1. CONSERVANCY
ISAAC OROKO
Bsc. Evh-MU
By Isaac Oroko EHS KMTC Kabarnet
Campus 1

2. CONSERVANCY SYSTEMS
Aim:-
To equip the learner with knowledge,
skills and attitudes, to be able to select,
design and advice on construction of
conservancy systems.
By Isaac Oroko EHS KMTC Kabarnet
Campus 2

3. Objectives
Define terms used in conservancy
Describe the importance of excreta disposal
Outline diseases associated with excreta
Design conservancy systems
Describe conservancy systems with the aid of
sketches
Prepare estimates for particular system and
supervise the construction of the same
Discuss appropriateness of conservancy
systems in different premises
Explain merits and demerits of each
conservancy system
Discuss legislation relevant to conservancy
By Isaac Oroko EHS KMTC Kabarnet Campus 3

4. Definition of terminologies used
Conservancy
This is that system of sanitation where excreta is
returned directly to earth and includes where it
is temporarily stored pending removal as in
bucket latrine. In this system, water is not used
for the conveyance of the excreta.
Dry conservancy
Is where no water at all except the water that is
used in washing the floor of the toilet.
By Isaac Oroko EHS KMTC Kabarnet Campus 4

5. Terminologies continued
Semi-dry conservancy
It is where a little amount of water is used to
facilitate operation for example in aqua privy,
pour flush etc.
Night soil
It is another term for excreta
Note:
Objects of excreta disposal is composed of the
unwanted products of the human body
By Isaac Oroko EHS KMTC Kabarnet Campus 5

6. Significance/objectives of excreta disposal
Reduce gastro-enteric diseases
Avoid water contamination
Avoid land contamination
Eliminate nuisance from smell
It is unsightly
Promote health and improve state of hygiene
Reduce flies and other vermins
It can be reused as manure
By Isaac Oroko EHS KMTC Kabarnet Campus 6

7. Transmission of diseases
NB:-
•Methods of excreta disposal can be by use of
water
carriage system or use of conservancy system
•Humans themselves are the main reservoir of
most diseases that affect them.
•Transmission of excreta-related diseases from one
host to another (or the same host) normally
follows one of the routes shown in Fig. below.
•Poor domestic and personal hygiene, indicated by
routes involving food and hands, often diminishes
or even negates any positive impact of improved
excreta disposal on community health.
By Isaac Oroko EHS KMTC Kabarnet Campus 7

8. Transmission of diseases cont’
As shown in the figure, most routes for
transmission of excreta-related
diseases are the same as those for
water-related diseases, being
dependent on faecal-oral transmission
(waterborne and water-washed) and
skin penetration (water-based with an
aquatic host; soil-based but not faecal-
oral; and insect vector with vector
breeding on excreta or in dirty water).
By Isaac Oroko EHS KMTC Kabarnet Campus 8

9. By Isaac Oroko EHS KMTC Kabarnet Campus 9

10. Water borne diseases and fly related
Excreta is associated with diseases through the
Faecal – oral route e.g.
Dysentery
Cholera
Typhoid
Poliomyelitis
Infective hepatitis
Other gastro – enteric
diseases By Isaac Oroko EHS KMTC Kabarnet Campus 10

11. Continuation
Parasitism (Helminths)
Tapeworms
Roundworms
Hookworms
Flatworms
Other conditions of faecal – oral route
Diarrhoea
Vomiting
Other gastro-intestinal infections
By Isaac Oroko EHS KMTC Kabarnet Campus 11

12. Transmission routes
Diarrheal diseases that is, dysenteries and enteric
fevers have three things in common the organisms are
passed in:-
Faeces of the infected person
Water
Food
Faeces of the infected person
Faeces of infected animal water food

Susceptible person
By Isaac Oroko EHS KMTC Kabarnet Campus 12

13. Contact to contact
Transmission routes of viral
diseases e.g.
Hepatitis A – through faeces
Polimyelitis – in crowded
places where sanitation is poor
By Isaac Oroko EHS KMTC Kabarnet Campus 13

14. Faecal – oral to oral route
Faeces of infected person
Water Food
Susceptible person
By Isaac Oroko EHS KMTC Kabarnet Campus 14

15. Transmission routes of worm infections
through soil, water and animals
Soil based worms
Faeces of infected person
Crops(vegetable foods) Soil
Susceptible person
By Isaac Oroko EHS KMTC Kabarnet Campus 15

16. continuation
Worms with aquatic hosts
Infected person

Water Excreta
Cyclops Snail (Schistosome)
(guinea worm)
Fish and shell
fish

Susceptible person
By Isaac Oroko EHS KMTC Kabarnet Campus 16

17. Continuation
Worms with animal hosts
Faeces of infected person
Soil
Infected cow/pig/sheep/goat
Infected food
Susceptible person
By Isaac Oroko EHS KMTC Kabarnet Campus 17

18. Water related insect-borne diseases
Transmission route of water related
Blood of infected person
Mosquitoes/flies
Susceptible person
By Isaac Oroko EHS KMTC Kabarnet Campus 18

19. Continuation
Skin and eye disease (transmission route)
Infected person
Susceptible person
Note: All these diseases depend on
Poor water supply
Poor sanitation
Improper disposal of faeces
Poor hygiene
Insects which breed in waterBy Isaac Oroko EHS KMTC Kabarnet Campus 19

20. Other diseases directly related to
poor water supply and sanitation
Campylobacter
Giardiasis
Paratyphoid
Clonorchiasis
Enterobiasis
By Isaac Oroko EHS KMTC Kabarnet Campus 20

21. Problems associated with conservancy systems
Fly breeding and other vermin
Smell nuisances
Site problems that is unsightliness
Pollution of water
Pollution of land
Makes the place aesthetically objectionable
In some communities it is unacceptable
Drainage problems (the disposal of urine, water
used to clean or for washing the latrine incase of
blockage etc)
Sense of hygiene becomes very low
By Isaac Oroko EHS KMTC Kabarnet Campus 21

22. Disease control and pollution
The basic criteria on conservancy system to be
used or the criteria to determine type of system
to adopt (reasons for disposal)
Avoidance of water contamination
especially the underground water
where the water table is very high
Avoidance of soil contamination
Minimizing of fly-breeding
(control of fly-breeding in the
bucket latrine is very difficult)
Minimizing of smell
By Isaac Oroko EHS KMTC Kabarnet Campus 22

23. Pollution cont’
Minimizing of handling of excreta
that is minimize direct handling of
excreta for example in bucket
latrines.
Suitability of the site to be used for
example the prevailing wind, the sub-
soil, the rocks, the underground
water etc.
Acceptability of the type of
conservancy to be used by the users
(community).
Simplicity and ease of maintenance.By Isaac Oroko EHS KMTC Kabarnet Campus 23

24. Various conservancy systems
Open defecation
Cat system (shallow pit)
Traditional pit latrine (simple)
Aqua privy
Pour flush
Ventilated improved pit latrine (VIP)
Chemical closet
Bucket latrine
Over hung
Compost
Trench latrine
By Isaac Oroko EHS KMTC Kabarnet Campus 24

25. Open defecation
Is where there are no latrines, and
people resort to defecate in the open
This may be indiscriminate or in
special places for defecation
generally accepted by the
community such as defecation fields,
rubbish and manure heaps or under
trees
Note that due to the health hazards
created and the degradation of the
environment, open defecation
should not be encouraged
By Isaac Oroko EHS KMTC Kabarnet Campus 25

26. A problem of open defecation areas and flying
toilets in
 Mathare
NGO’s have been actively involved in mapping
water and sanitation, open defecation areas and
open drainages in Mathare.
 Its very surprising to see people shitting in an
open ground, not worrying about people
watching them.
By Isaac Oroko EHS KMTC Kabarnet Campus 26

27. Continuation of mathare
 Children in Mathare lack playing grounds and
recreational facilities.
 This is because a lot of free space is being used
by open defecation areas therefore forcing the
children to play near roads which often leads to
accidents.
By Isaac Oroko EHS KMTC Kabarnet Campus 27

28. By Isaac Oroko EHS KMTC Kabarnet Campus 28

29. Disadvantages
It encourages flies which spread
faeces – related diseases
In moist ground, the larvae of
intestinal worms develop, and;
faeces and larvae may be carried
by people and animals.
Surface water run – off from places
where people have defecated
results in water pollution
By Isaac Oroko EHS KMTC Kabarnet Campus 29

30. Note:
That due to the health hazards created
and the degradation of the
environment, open defecation should
not be encouraged
By Isaac Oroko EHS KMTC Kabarnet Campus 30

31. Cat system (shallow pit)
People working in the farms may dig a small hole
each time they defecate and then cover the
faeces with soil
Pits about 300mm deep may be used for several
weeks
The excavated soil is heaped beside the pit and
some is put over the faeces after each use i.e.
defecation
By Isaac Oroko EHS KMTC Kabarnet Campus 31

32. CAT SYSTEM
By Isaac Oroko EHS KMTC Kabarnet Campus 32

33. Advantages and disadvantages
No cost
Benefit to farmers as fertilizer/manure
Decomposition in shallow pits is rapid because
of the large bacterial population in the top soil
Flies breed in large numbers
Hookworm larvae spread around the holes
Hookworm larvae can migrate upwards from
excreta buried less than 1metre deep to
penetrate the soles of the feet of subsequent
users
By Isaac Oroko EHS KMTC Kabarnet Campus 33

34. By Isaac Oroko EHS KMTC Kabarnet Campus 34

35. Aqua-Privy
•An aqua-privy functions in a similar
manner to a septic tank whilst
avoiding the need for a consistent
water supply to operate a flush toilet.
•The water will drain off the top and
the sludge needs to be emptied on a
regular basis.
• An advantage of the aqua privy is that
it reduces odours.
•However, regular emptying could
become an onerous requirement.
By Isaac Oroko EHS KMTC Kabarnet Campus 35

36. Aqua privy
By Isaac Oroko EHS KMTC Kabarnet Campus 36

37. Advantages
Does not require a piped water
supply as a user can defecate
directly into the tank
It is a cheaper form of a septic
tank
By Isaac Oroko EHS KMTC Kabarnet Campus 37

38. Disadvantages
•The system can fail to reduce
smells if the water seal is not
maintained
•Water must be available and
plentiful
•Requires emptying
•Permeable land is needed to
drain effluent
By Isaac Oroko EHS KMTC Kabarnet Campus 38

39. By Isaac Oroko EHS KMTC Kabarnet Campus 39

40. Pour-flush
•Where water is more widely available or
traditionally used for anal cleansing a
pour flush latrine may be appropriate and
can bring a number of further benefits on
top of simple or VIP latrines.
•A water-seal is created by a plastic u-bend
which prevents bad odour and flies
affecting the user (this system is less
susceptible to building errors than the VIP
system).
•The system only requires a few litres of
water and so should not put a strain on
resources and could be provided by
greywater from the kitchen.By Isaac Oroko EHS KMTC Kabarnet Campus 40

41. Pour flush latrines
By Isaac Oroko EHS KMTC Kabarnet Campus 41

42. Advantages
•The system effectively reduces levels
of flies, mosquitoes and odour
•The system can incorporate an offset
pit (see figure above) and so can be
installed inside a household
•The installations are easy to keep
clean
•They work easily i.e. the construction
is not as complicated as a VIP latrine
By Isaac Oroko EHS KMTC Kabarnet Campus 42

43. Disadvantages
•Requires a supply of water to
operate the system
•The water seal prevents the use of
solid anal cleansing materials
•The plastic pan requires increased
skill to produce
•More expensive than simpler types
By Isaac Oroko EHS KMTC Kabarnet Campus 43

44. By Isaac Oroko EHS KMTC Kabarnet Campus 44

45. Simple pit latrine
The simplest form of pit
latrine is a hand dug pit that is
unlined and covered with a
series of wooden logs strapped
together allowing the user to
defecate into the pit.
This system can gradually be
improved.
By Isaac Oroko EHS KMTC Kabarnet Campus 45

46. Simple pit latrine
By Isaac Oroko EHS KMTC Kabarnet Campus 46

47. Advantages
Construction costs are low
(householders can perform a large part
of the work themselves)
Technology is simple and
understandable
Allow range of anal cleansing materials
Do not require water to operate
By Isaac Oroko EHS KMTC Kabarnet Campus 47

48. Disadvantages
•Possible groundwater
contamination if the pit is not
completely lined
•Not easy to construct in rocky
or unstable ground
•Fly and smell nuisance
By Isaac Oroko EHS KMTC Kabarnet Campus 48

49. By Isaac Oroko EHS KMTC Kabarnet Campus 49

50. Ventilated Improved Pit (VIP)
Latrine
•During the 1980s the VIP latrine was
developed in Zimbabwe.
•The main drivers for design were to
eliminate two unpleasant aspects of
using on-site sanitation systems, flies
and smell.
•Furthermore, the reduction of flies
can also reduce the transmission of
disease.
By Isaac Oroko EHS KMTC Kabarnet Campus 50

51. Continuation
Put simply, the technology facilitates
the flow of air through the system.
One important aspect is that the inside
of the toilet should remain dark as
means of attracting flies up a vent pipe
where they will eventually die and fall
back into the latrine.
Further information and details on
construction can be found in the
Practical Action technical brief
‘Ventilated Improved Pit Latrine’.
By Isaac Oroko EHS KMTC Kabarnet Campus 51

52. By Isaac Oroko EHS KMTC Kabarnet Campus 52

53. VIP continuation
•The interior of the superstructure
should be darker than the daylight
outside and the superstructure
building should be well ventilated so
as to allow the flow of air into the pit.
•The pit should have a vent pipe which
should be at least 100mm diameter
and should extend from the pit to
about one metre above the roof, and
the top of it should be fitted with a
fine-mesh stainless steel, or
aluminium fly-screen.
By Isaac Oroko EHS KMTC Kabarnet Campus 53

54. VIP continuation
•Flies which are drawn by smell into the
pit will be attracted up the vent pipe by
the brightness of daylight at the top it,
but cannot escape because of the
screen.
•Wind passing over the vent pipe will
cause an up-draught, removing any
smell and helping to draw flies up to
the top of the pipe
By Isaac Oroko EHS KMTC Kabarnet Campus 54

55. By Isaac Oroko EHS KMTC Kabarnet Campus 55

56. Cost estimate for a ventilated improved pit latrine

S. NoParticulars Quantity Unit
Cost
Amount
Kesh
1 Cement 2bags
2 Sand 50 bags
3 Pre-cast cement squatting slab with
drop-hole and footrest
1 No.
4 PVC air-vent pipe 3” dia-7 with
perforated top cover
1 No.
5 GCI sheets 2 Nos.
6 Timber d oor with tin sheet 5x2 feet 1 No
7 Country Bricks, 9 inch size 400 nos.
8 Masonry charges 2 days
9 Unskilled labour charges 2 days
10 Transport charges
Total Cost (approx.)
By Isaac Oroko EHS KMTC Kabarnet
Campus 56

57. Advantages
•Construction costs are low (householders
can perform a large part of the work
themselves)
•Technology is simple and understandable
•Allow the use of a range of anal cleansing
materials
•Do not require water to operate
•Controls smells and flies
By Isaac Oroko EHS KMTC Kabarnet Campus 57

58. Disadvantages
Possible groundwater contamination
if the pit is not completely lined
Not easy to construct in rocky or
unstable ground
Does not control mosquitoes
Vent pipe increases costs and can
make construction more complicated
Need to keep inside of latrine dark
Increased odour outside
By Isaac Oroko EHS KMTC Kabarnet Campus 58

59. By Isaac Oroko EHS KMTC Kabarnet Campus 59

60. Chemical closet
Modern chemical toilets are normally of the
following types:
•A cylindrical bucket fitted with a plastic
seat and lid; the capacity is usually 20-30
litres; after the bucket has been emptied
and cleaned, about 50 mm depth of fluid is
put in.
•Two tanks: the flushing-liquid reservoir
contains a mixture of fresh water and a
deodorizing chemical which is pumped
manually to the rim of the pan; discharge
is to the waste-storage tank.
By Isaac Oroko EHS KMTC Kabarnet Campus 60

61. Definition of chemical closet
Is a toilet without conventional
water and drain connections;
contains a fluid, usually with a
disinfectant and deodorant,
which neutralizes waste matter
chemically.
By Isaac Oroko EHS KMTC Kabarnet Campus 61

62. Chemical closet continuation
A single tank in which a flushing
pan is fitted; a manual or
electrically operated pump
recirculates oil, drawing it from the
base of the tank through a filter
and discharging it around the rim
of the pan; the pan has a counter-
balanced flap so that the contents
cannot be seen.
By Isaac Oroko EHS KMTC Kabarnet Campus 62

63. By Isaac Oroko EHS KMTC Kabarnet Campus 63

64. Cont’
A chemical toilet is a toilet using
chemicals to deodorize the waste
instead of simply storing it in a
hole, or piping it away to a sewage
treatment plant.
These toilets are most commonly
found on airplanes, trains,
caravans and motorhomes,
identified with a blue-colored dye
in the bowl water.
By Isaac Oroko EHS KMTC Kabarnet Campus 64

65. Recirculating oil toilet
By Isaac Oroko EHS KMTC Kabarnet Campus 65

66. Chemical closet continuation
•The fluid is normally a chemical diluted with
water which renders excreta harmless and
odourless.
•When containers are full, the contents are
tipped into pits or sewers, or pumped into
storage tanks.
•Chemical toilets are used in aircraft, long-
distance coaches, caravans, vacation homes
and construction sites.
•The chemical is expensive.
By Isaac Oroko EHS KMTC Kabarnet Campus 66

67. By Isaac Oroko EHS KMTC Kabarnet Campus 67

68. Bucket latrines
The system in which excreta are removed
from bucket latrines (also called night soil
latrines or earth closets) is one of the oldest
forms of organized sanitation.
Bucket latrines are still found in many towns
and cities in Africa, Latin America and Asia,
because their low capital cost makes them
attractive to underfunded local authorities.
In some rural and peri-urban areas,
members of households take night soil to
manure heaps or apply it directly to fields as
fertilizer. By Isaac Oroko EHS KMTC Kabarnet Campus 68

69. Bucket latrine continuation
In towns and cities, night soil is
often collected by sweepers
engaged by householders on
contract, or by the local authorities.
Buckets are usually emptied into
larger containers near the latrine.
In some places labourers carry
these containers by hand or on
their heads; hand-carts, animal-
drawn carts, bicycles and tricycles
are also used.
By Isaac Oroko EHS KMTC Kabarnet Campus 69

70. Continuation
Night soil collection should never
be considered as an option for
sanitation improvement
programmes, and all existing
bucket latrines should be
replaced as soon as possible.
The number of bucket latrines is
declining rapidly.
By Isaac Oroko EHS KMTC Kabarnet Campus 70

71. By Isaac Oroko EHS KMTC Kabarnet Campus 71

72. Good operation
•A container made of non-corrosive material
is placed beneath a squatting slab or seat in
the bucket chamber, with rear doors which
should be kept shut except during removal
and replacement of the bucket.
•The bucket chamber should be cleaned
whenever the bucket is removed.
•The squat hole should be covered by a fly
proof cover when not in use.
•The cover of the seat should be hinged and
the cover of the squatting slab should have
a long handle.
By Isaac Oroko EHS KMTC Kabarnet Campus 72

73. By Isaac Oroko EHS KMTC Kabarnet Campus 73

74. continuation
•At regular intervals (preferably each
night) the container should be removed
and replaced by a clean one.
• Full containers should be taken to
depots or transfer stations where they
are emptied, washed and disinfected
with a phenol or cresol type of
disinfectant.
•In some towns it is the practice to
provide two buckets painted in different
colours for each latrine.
By Isaac Oroko EHS KMTC Kabarnet Campus 74

75. Continuation
•Containers should be kept covered
with tight-fitting lids while in transit
and the operators should be provided
with full protective clothing.
•Proper supervision and management
are essential.
•Defective buckets should be repaired
or replaced and transport vehicles
should be kept in good order.
By Isaac Oroko EHS KMTC Kabarnet Campus 75

76. continuation
In some systems, urine is diverted
away from the buckets to reduce the
volume to be dealt with.
It is usually channeled to soak pits,
but may be collected separately and
used directly as fertilizer.
Water used for washing latrines and
bucket-chambers should pass to soak
pits, and should not be allowed to
pollute the ground around the
latrines.By Isaac Oroko EHS KMTC Kabarnet Campus 76

77. Disposal methods
The practice of dumping night soil
indiscriminately into streams or on open land is
objectionable and causes health hazards.
•Sewers
Bucket latrines are sometimes found in
towns that are partially provided with
sewers, in which case it may be convenient
to discharge the night soil into a main
sewer.
Tipping points on sewers require careful
design to prevent contamination of
surrounding areas and should be as near
to the sewage works as possible.
Extra water may have to be added to
prevent blockage of the sewers.By Isaac Oroko EHS KMTC Kabarnet Campus 77

78. continuation
•Sewage treatment works
Night soil may be discharged into the sewage flow at
the works inlet, at sedimentation or aeration tanks,
or directly to waste stabilization ponds or sludge
digestion tanks.
•Trenching
Trenches about 1 m deep and 1 m wide may be filled
with nightsoil to within not less than 300 mm of the
top.
The trench is then backfilled with excavated soil,
which should be well compacted to prevent the
emergence of flies or the excreta being dug up by
animals.
At the end of each day any exposed excreta must be
covered with at least 200 mm of soil, well compacted.
By Isaac Oroko EHS KMTC Kabarnet Campus 78

79. continuation

After backfilling, the trench should
remain untouched for at least two years,
after which it can be re-excavated for
reuse and the contents used as fertilizer.
The trenching site should be close to the
collection area but away from
residential areas.
It should have deep and porous soil, be
well above the water table, and not be
subject to flooding.
By Isaac Oroko EHS KMTC Kabarnet Campus 79

80. Disposing of excreta from bucket
latrines by trenching
By Isaac Oroko EHS KMTC Kabarnet Campus 80

81. Reuse
Night soil can be used as a
fertilizer after all pathogens
have been destroyed.
It may also be added to
ponds for fish cultivation.
By Isaac Oroko EHS KMTC Kabarnet Campus 81

82. By Isaac Oroko EHS KMTC Kabarnet Campus 82

83. Overhung latrines
•An overhung latrine consists of
a superstructure and floor built
over water.
•A squat hole in the floor allows
excreta to fall into the water.
•A chute is sometimes provided
from the floor to the water.
By Isaac Oroko EHS KMTC Kabarnet Campus 83

84. Continuation
•Overhung latrines should never
be built in places where pit
latrines can be provided.
•However, they may be the only
possible form of sanitation for
people living on land that is
continuously or seasonally
covered with water.
By Isaac Oroko EHS KMTC Kabarnet Campus 84

85. Overhung latrine
By Isaac Oroko EHS KMTC Kabarnet Campus 85

86. Advantages and disadvantage
May be the only feasible
system for communities
living over water
It is cheap
May result in serious health
hazards
By Isaac Oroko EHS KMTC Kabarnet Campus 86

87. By Isaac Oroko EHS KMTC Kabarnet Campus 87

88. Cesspits
•Cesspits, like vaults, are
watertight tanks with sealed
covers (to keep out mosquitoes).
•They differ from vaults in that
they are usually located outside
the premises and collect sullage
as well as the wastes from
water closets.
By Isaac Oroko EHS KMTC Kabarnet Campus 88

89. Continuation
•The capacity may be sufficient
for up to several months' use.
•The cost of providing a regular
removal service for all the
wastewater from a house with
a good supply of piped water
can be very high, making
cesspits an expensive form of
sanitation.
By Isaac Oroko EHS KMTC Kabarnet Campus 89

90. By Isaac Oroko EHS KMTC Kabarnet Campus 90

91. By Isaac Oroko EHS KMTC Kabarnet Campus 91

92. Compost latrines
A composting toilet is a predominantly
aerobic processing system that treats
excreta, typically with no water or small
volumes of flush water, via composting or
managed aerobic decomposition.
This is usually a faster process than the
anaerobic decomposition at work in most
wastewater systems, such as septic
systems.
Composting toilets are often used as an
alternative to central wastewater
treatment plants (sewers) or septic systems.
By Isaac Oroko EHS KMTC Kabarnet Campus 92

93. Why compost latrine is selected
Typically they are chosen
To alleviate the need for water to
flush toilets,
To avoid discharging nutrients
and/or potential pathogens into
environmentally sensitive areas, or
To capture nutrients in human
excreta. Several manufactured
composting toilet models are on the
market, and construct-it-yourself
systems are also popular.
By Isaac Oroko EHS KMTC Kabarnet Campus 93

94. Operating process
Although there are many designs, the
process factors at work are the same.
Rapid aerobic composting will be
thermophilic decomposition in which
bacteria that thrive at high temperatures
(40-60 °C / 104-140 °F) oxidize (break
down) the waste into its components,
some of which are consumed in the
process, reducing volume, and
eliminating potential pathogens
By Isaac Oroko EHS KMTC Kabarnet Campus 94

95. continuation
Drainage of excess liquid or "leachate" via
a separate drain at the bottom of the
composter is featured in some
manufactured units, as the aerobic
composting process requires moisture
levels to be controlled (ideally 50% +/- 10):
Too dry, and the mass decomposes slowly
or not at all
Too wet and anaerobic organisms thrive,
creating undesirable odors
This separated liquid may be diverted to a
gray water system or collected for other
uses.
By Isaac Oroko EHS KMTC Kabarnet Campus 95

96. By Isaac Oroko EHS KMTC Kabarnet Campus 96

97. Pail closet
A pail closet (or pail privy) was a room
used for the disposal of human excreta,
under the pail system (or Rochdale
system) of waste removal.
The closet was a small outdoor privy
which contained a seat, underneath
which a portable receptacle was placed.
This pail, into which the user would
defecate, was removed and emptied by
the local authority, on a regular basis.
The contents would either be incinerated
or composted into fertilizer.By Isaac Oroko EHS KMTC Kabarnet Campus 97

98. LEGISLATION RELEVANT TO
CONSERVANCY
Public Health Act Cap 242
Local Authorities Act Cap 265
The Building Code
By Isaac Oroko EHS KMTC Kabarnet Campus 98