United Republic of Tanzania - Wash In Schoolswashinschoolsmapping.com/wengine/wp-content/uploads/2015/10/... · PL8-BQ Bill of quantity – for burnt brick superstructure (boys) with

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United Republic of Tanzania

Toolkit No.2: Technical Options for School WASH

Part I of 2

Options and Operation & Maintenance

First Draft for Piloting and Consultation

Oct 2010

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Toolkit No.2: Technical Options for School WASH

Part I of 2

Options and Operation & Maintenance

Oct 2010

All pictures by: Rashid Mbago

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Contents

Contents ....................................................................................................... 2

Technical Drawings and Bills of Quantities .................................................... 4

1 How to use this toolkit ........................................................................... 7

2 Technical options for water supply including drainage ........................... 8

2.1 Boreholes, shallow wells, springs, piped systems .................................... 8

2.1.1 Rainwater harvesting ................................................................................. 9

2.1.2 Shallow wells ............................................................................................ 11

2.1.3 Stand pipe (piped scheme) ...................................................................... 12

2.1.4 Protected spring ....................................................................................... 13

2.1.5 Boreholes ................................................................................................. 14

2.1.6 Small dams (charco dams) ....................................................................... 15

2.2 Drainage from water points and fencing ................................................ 16

2.3 Accessibility to water supply for children and adults with disabilities .... 18

2.4 Water quality and water treatment for drinking water .......................... 20

3 Technical options for latrines, urinals and bathing units ...................... 25

3.1 Latrine types ......................................................................................... 25

3.1.1 Improved pit latrine ................................................................................. 26

3.1.2 Ventilated improved pit latrine ............................................................... 29

3.1.3 Double vault ventilated improved pit latrine .......................................... 31

3.1.4 EcoSan latrine (double vault) - wet .......................................................... 33

3.1.5 Pour flush latrine (off set) ........................................................................ 35

3.1.6 Flush latrine with cistern ......................................................................... 37

3.1.7 Biogas-latrine ........................................................................................... 39

3.2 Latrine block designs versus costs ......................................................... 40

3.3 Lining materials for different ground conditions .................................... 43

3.4 Pit emptying ......................................................................................... 44

3.5 Urinals .................................................................................................. 46

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3.6 Girl friendly designs, bathing units or girls hygiene units ........................ 48

3.7 Accessibility to sanitation for children and adults with disabilities ......... 50

3.7.1 Pathways and ramps ................................................................................ 50

3.7.2 Doors ........................................................................................................ 55

3.7.3 Layout and handrails ................................................................................ 57

3.7.4 Latrine seats ............................................................................................. 59

3.8 Technical options for hand-washing ...................................................... 64

3.9 Technical options for solid waste disposal & sanitary pad disposal ........ 67

3.9.1 Waste collection units and waste pits ..................................................... 67

3.9.2 Disposal of sanitary pads ......................................................................... 70

3.10 School kitchens and dining areas ........................................................... 71

Appendix 1 – List of tables and figures ........................................................ 74

Tables ......................................................................................................... 74

Figures ........................................................................................................ 74

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Technical Drawings and Bills of Quantities

Part 1 of 2 of the Toolkit 2: Technical Options for School WASH (this document) is also accompanied by Part 2 of 2, which has the following technical drawings and bills of quantities included.

Drg BofQ Description Original design

Rainwater Harvesting Tanks

RW1(a) Bag made of Mariakani cloth for building a 3 cum jar of ferrocement

ASAL Consult

RW1(b) Standard design of a 3 cu.m ferrocement jar

(below ground collection)

ASAL Consult

RW1-BQ Bill of quantities for a 3 cu.m ferrocement jar ASAL Consult

RW2 Standard design for a 5 cu.m tank built of concrete in situ


ASAL Consult

RW2-BQ Bill of quantities and cost for a 5 cu.m tank of concrete in situ

ASAL Consult

RW3 Standard design of a 10 cu.m tank built of burnt bricks


ASAL Consult

RW3-BQ Bill of quantities and cost of a 10 cu.m tank built of burnt bricks

ASAL Consult

RW4 Standard design of a 23 cu.m ferrocement tank


ASAL Consult

RW4-BQ Bill of quantities of a 23 cu.m ferrocement tank


ASAL Consult

RW5 Standard design of a 46 cu.m ferrocement tank


ASAL Consult

RW5-BQ Bill of quantities of a 46 cu.m ferrocement tank


ASAL Consult

RW6 Standard design of water storage tank for 10 cu.m of burnt bricks

ARU & ASAL

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(above ground collection) Consult

RW6-BQ Bill of quantities for a storage tank for 10 cu.m made of burnt bricks

(above ground collection)

ARU & ASAL Consult

RW7 Standard design of water storage tank for 30 cu.m of ferrocement


ARU & ASAL Consult

RW6-BQ Bill of quantities for a water storage tank for 30 cu.m of ferrocement


ARU & ASAL Consult

Pit Latrines

PL1 Cement block (girls) – below ground – fully lined WEDC

PL2 Cement block (boys) – below ground – partially lined WEDC

PL3 Burnt brick (boys) – below ground – fully lined WEDC

PL4 Burnt brick (girls) – below ground – partially lined WEDC

PL5 Cement block (boys) – floor construction WEDC

PL6 Cement block (girls) – floor construction WEDC

PL7 Mud superstructure (boys) WEDC

PL7-BQ Bill of quantity – for mud-superstructure (boys) with fully / partially lined pit

WEDC

PL8 Burnt brick superstructure (boys) WEDC

PL8-BQ Bill of quantity – for burnt brick superstructure (boys) with fully / partially lined pit

WEDC

PL9 Burnt brick superstructure (girls) WEDC

PL9-BQ Bill of quantity – for burnt brick superstructure (girls) with fully / partially lined pit

WEDC

PL10 Cement block superstructure (girls) WEDC

PL10-BQ Bill of quantity – for cement block superstructure (girls) with fully / partially lined pit

WEDC

PL11 Urinal (boys) WEDC

PL12 Pit latrine floor plan and sections – girls ARU & WEDC

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PL13 Pit latrine floor plan and sections – boys

ARU & WEDC

Pour Flush Latrines

PFL1 Pour flush latrine, floor plan and elevation (girls) EEPCO

PFL1-BQ Bill of quantities - pour flush latrine (girls) EEPCO

PFL2 Pour flush latrine, floor plan and elevation (boys) EEPCO

PFL1 - BQ Bill of quantities - pour flush latrine (boys) EEPCO

Double Vault Ventilated Improved Pit Latrine

DVVIP1 Double Vault VIP latrine (boys) EEPCO

DVVIP1-BQ

Bill of quantities – double VIP latrine (boys) EEPCO

DVVIP2 Double Vault VIP latrine (girls) EEPCO

DVVIP2-BQ

Bill of quantities – double VIP latrine (girls) EEPCO

Ventilated Improved Pit Latrines

VIP1 VIP latrine (boys) - (no disabled access) MOEVT

VIP2 VIP latrine (girls) – (no disabled access) MOEVT

Water Closet

WC1 Water closet latrine block (boys and girls with disabled access)

MOEVT

Hand-washing

HW1 Tippy tap

HW2 Ferrocement jar fed from rainwater harvesting, 1 m3 ARU

HW4 Three unit pedestal sink with concrete surround ARU

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1 How to use this toolkit

This toolkit provides technical options for school WASH which can be selected based on the:

Available resources for construction

Ability to maintain (clean, repair, empty) the technology

Likely lifespan and ability to replace the technology

Cultural appropriateness

Availability of water

In particular for latrines, one of the most expensive components of school WASH, several options have been offered based on financial capacity. These include:

Full or partial lining

Mud walls, burnt brick, concrete block or other material

Thatch, iron sheet or other roofing materials

Each example technology is accompanied by the following information:

Name of the technology

Brief description of the technology

Picture

O&M requirements

Technical drawings

(When applicable)

Bill of Quantities

(When applicable)

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2 Technical options for water supply including drainage

2.1 Boreholes, shallow wells, springs, piped systems

The options available for improved water supply for schools include:

Boreholes with hand pumps or pumps and engines or generators

Shallow wells with hand pumps or bucket and windlass

Protected springs

Piped systems to stand posts

Rainwater harvesting

As most of these options require a specialist to design and install, this guideline will not cover them in detail. The guideline will focus on the aspects that can be supported locally by non specialists, such as how to ensure appropriate drainage, the construction and operation and maintenance of rainwater harvesting systems, accessibility for children and adults with disabilities and water treatment for drinking water.

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2.1.1 Rainwater harvesting


Rainwater harvesting


Rainwater is preferably collected from roofs made of metal sheets or tiles.The system consists of the roof of the building from where rain water flows through gutters and downpipes into collection tanks. Normally water may be abstracted from the tank by one or several taps; in the case of large tanks a motorised pump, hand-pump or a bucket and rope system may be used.

Fig 1. Rainwater harvesting

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Fig 2. Rainwater harvesting gutters

O&M requirements

Clean the catchment roof and gutters.

Replace broken or corroded parts of the system.

At the start of each rainy season empty the storage tank, remove silt and debris, diverge the first rain water.

Repair damaged and cracked parts of the system.

Chlorination can be done as recommended by manufacturer or water authorities.

Technical drawings

Rainwater harvesting tanks can be constructed using various construction methods. Some drawings and B of Qs are included in this manual, but alternatives can also be used. The examples (currently) included in this manual have collection points below the ground. Practice in Tanzania to have the collection point raised above the ground which is advisable to remove the water away from the collection point.

Drawings: RW1; RW2; RW3; RW4; RW5

Bill of Quantities

BofQs: RW1-BQ; RW2-BQ; RW3-BQ; RW4-BQ; RW5-BQ

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2.1.2 Shallow wells


Shallow wells


A shallow well is a type of well that uses simple method of exploiting groundwater. They can be constructed and maintained with local resources at very low costs. Shallow wells are suitable in areas with a high groundwater table and good water quality. The technology is relevant if there is enough water in the soft formation rock within 10-20 m from ground surface. They must be constructed with a well constructed drainage curtain to collect the waste water and to direct it away from the collection area to ensure hygiene and prevent contamination of the well water.

Fig 3. Shallow well with handpump

O&M requirements

Regularly check and repair fence, damage and cracks in the apron and the drainage channel.

Make sure the soak away is clear and operational.

Remove debris from the bottom of the well and deepen the well as necessary.

Technical drawings

Not provided – refer to technical experts

Bill of Quantities


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2.1.3 Stand pipe (piped scheme)


Piped scheme with stand pipe


Stand pipe is a supply system connected to public water supply system locally referred as domestic point (DP). The taps can be a globe or a self-closing type. The column or wall may be of wood, brickwork, dry stone masonry and concrete. Some stand pipes have a regulating gate valve in the connection to the mains that can be set and locked to limit maximum flow.

Fig 4. Standpipe

O&M requirements

Replace worn and damaged parts of the system.

Repair taps by replacing washers or replacing taps when they get worn.

Repair damage and cracks in the apron and the drainage channel.

Make sure the soak away is operational.

Taps need to be turned off properly after use to prevent wastage

Technical drawings


Bill of Quantities


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2.1.4 Protected spring


Protected spring


These are water source where water has percolated through the soil layers and re-appears from the ground and may flow away and collect to form streams, rivers or lakes downstream. The point where the water comes out from the ground is protected from damage or contamination. Spring water from protected springs can usually be free from pathogens and if the dissolved minerals are within permitted parameters they provide good quality drinking water.

Fig 5. Protected spring

O&M requirements

Clean the areas uphill from the spring, remove dead vegetation.

Repair the security fence.

Repair damage and cracked part of the system. Make sure the soak away is operational.

Technical drawings


Bill of Quantities


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2.1.5 Boreholes


Boreholes


Deep boreholes are suitable in areas where surface water sources and shallow aquifers tend to dry up during the dry season. Moreover the quality and cost involved in the treatment of surface water sources makes it advantageous to use deep groundwater as in most cases, deep ground water provides safe water for drinking except in areas where excessive levels of minerals are present.

Fig 6. Borehole, raised tank and pump house

O&M requirements

Replace worn and damaged parts of the system.

Carryout disinfection after flushing or when contamination is detected.

If defluoridation treatment plant is used ensure regular replacement of worn out parts including bone char.

The O&M for deep boreholes should be done in consultation with respective water department.

Technical drawings


Bill of Quantities


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2.1.6 Small dams (charco dams)


Charco dams


These are reservoirs for storing water, constructed in or adjacent to watercourses or within catchment areas, to store stream flow or surface runoff. Small dams are constructed by excavation, embankment or a combination of both and are typically designed to store 3,000 to 5,000 cubic metres of water, for one to two years storage.

Fig 7. Charco dam with fencing, stone filter and domestic point

O&M requirements

Ensure regular removal of silt, debris and vegetation from the dam and embankment.

Replace soil and re-compact the embankment.

Repair fence.

Remove silt and vegetation from feed channel

Technical drawings


Bill of Quantities


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2.2 Drainage from water points and fencing


Soakage pit, drainage channel, or collection chamber and fencing


These facilities collect wastewater from hand washing points and kitchen then direct it to either a soak-away pits or to a school garden. Fencing is provided to protect the water point facilities against damages.

Fig 8. Shallow well with handpump, fencing and drainage

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O&M requirements

Repair all worn out or damaged parts of the drainage system

Keep the drainage channel clear of debris and silt, ensure no ponding.

Ensure proper and regular cleaning.

Repair fence so it prevents animals from entering.

Technical drawings

Not provided, local designs should be developed using local materials

Bill of Quantities

Not provided, local designs should be developed using local materials

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2.3 Accessibility to water supply for children and adults with disabilities


Accessibility to water supply for children and adults with disabilities


Considering the layout and design of water facilities to enable children or adults with disabilities to also be able to access and utilise the facility. Design features include:

A ramp instead of a curb around a drainage platform

A solid slope / path to allow people using wheelchairs to access the water point

Posts or markers to assist people who are blind to find the direction to the facility

Sitting platform

Fig 9. Handpump with seat and wheelchair access

Pathway reaching the facility

with minimum with of 120cm

Ramp with a maximum slope

of 5%

Seating platform at 40cm

height within reach of the

pump

Dimensions of the area require

at least a 150cm turning space

Proper drainage

Firm, even and non-slip

surface

Taps with the longer handle or which can be pushed are easier to use for children and adults who have less ability to grip.

Fig 10. Tap designs that are easier to use with limited grip

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O&M requirements

Repair ramp and all worn parts.

Regular cleaning of the apron is required.

Technical drawings


Bill of Quantities


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2.4 Water quality and water treatment for drinking water

Table 1. Point of use water treatment options for schools

Options

Strengths Weaknesses Operation and maintenance requirements

Approximate capital cost (2010)

Approximate on-going cost per 1000

litres of water (2010)1

Ceramic bucket filter with silver in filter

Can remove all pathogens and also can remove turbidity (but would need more regular cleaning).

The ceramic filter itself is a bit fragile and can be damaged if not cleaned regularly.

Needs regular cleaning with a brush. After several months needs boiling.

USD 30 (or higher if larger safe storage container is used). (most of this cost is the bucket with tap which also acts as safe storage)

0.5 Euro

Boiling Kills all pathogens. Needs energy for boiling, hence time is required for fuel search. Environmental destruction if wood is used.

It requires regular cleaning of the container and needs fuel

Depends on the source of energy to be used for boiling.

17.85 Euro

Treatment with a household product

Kills all pathogens and provides residual effect to fight for

Does not work well in highly turbid water.

Pre-treatment of water is required if the water is turbid. Instructions must be followed.

No capital cost

(except for safe storage container)

0.24 Euro

1 1 International comparisons of price per 1,000 litres in the publication, ‘SMART disinfection solutions, Examples of small-scale disinfection products for safe drinking

water’, by NWP, Aqua for All, Witteveen Bos; KIT Publishers

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such as chlorine

recontamination.

Syphon filter

Removes pathogens and can be used with turbid water.

It filtration capacity is limited. No residual to fight recontamination. Not applicable to schools and other large institutions

Requires cleaning and replacement of worn parts

USD 15

(except for safe storage container)

0.51 Euro

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Water treatment options

Ceramic bucket filter

Fig 11. Ceramic bucket filter

Boiling

(with lid and concrete

floor)

Fig 12. Boiling

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Treatment with a household

product such as chlorine

Fig 13. Point of use water chlorination

Syphon filter

Fig 14. Syphon filter

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Biosand filter

Fig 15. Biosand filter

Candle filter

Fig 16. Ceramic candle filter

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3 Technical options for latrines, urinals and bathing units

3.1 Latrine types

The following sanitation options are recommended for schools:

Improved pit latrine (with Sanplat)

Ventilated improved pit latrine (VIP)

Double vault ventilated improved pit latrine

Ecosan latrines

Pour flush latrine (off set)

Flush latrine with cistern

Biogas-latrine (produces biogas) The subsequent sections outline briefly, the description of the technology, pictures, O&M, drawings and Bill of Quantities of the respective technology

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3.1.1 Improved pit latrine


Improved pit latrine (with Sanplat)


Improved pit latrine (with Sanplat) is a basic latrine that has a lower cost than other options. It consists of dug pit covered with a floor (log-soil or concrete). The improvement is done by installing impervious and washable slab namely SanPlat. The slab should be fixed securely and slightly raised above the ground to prevent water from flowing into the pit.

If the latrine is not a VIP, it should also have a close fitting lid for the hole. If it is a VIP then it should not have a led.

Fig 17. Improved pit latrine with hand-washing

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A sanplat for schools must provide a full washable slab, ie if a small sanplat such as this one are used then cement will also be needed to cover the full slab area

O&M requirements

Problem Operation or repairs required

Door broken or does not give privacy; loose hinges

Repair panels of door; put new hinges and grease them

Door cannot be locked from inside or outside

Find out causes of the damage; in case the lock do not function – replace locking devises , shatters and frames as appropriate

Cement plaster comes off the walls

Remove loose parts, clean and re-plaster with good cement mortar.

Leaking Roof Repair or replace damaged iron sheets on existing roof

Lid is broken or missing Replace the entire lid

Slab is broken, has holes or missing.

Replace entire slab

It is advisable the slab to be cast with adherence to approved ratios and if possible simple testing should be carried out

Damaged foundation Repair the foundation with cement mortar/concrete as appropriate

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Pits are full Dig a new one if the space is available and the toilet does not allow emptying Empty pit latrine if design allows Note: All school toilets should be designed to allow emptying

Dirty toilets Ensure proper and regular cleaning of the toilet

Technical drawings

PL1, PL2, PL3, PL4, PL5, PL6, PL7, PL8, PL9, PL10

Bill of Quantities

PL8-BQ, PL9-BQ, PL10-BQ

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3.1.2 Ventilated improved pit latrine

Name of technology

Ventilated improved pit latrine (VIP)


VIP latrines are designed to reduce two problems frequently encountered by traditional latrine systems: the smell and flies breeding. A VIP latrine differs from a traditional latrine by the inclusion of a vent pipe covered with a fly screen.

A common problem with VIPs in Tanzania are that the fly mesh is not replaced when it becomes damaged and the vent pipe also becomes brittle and splits and is not replaced.

Fig 18. Ventilated improved pit latrine with hand-washing

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O&M Requirement










Replace entire slab




VIP latrine: Vent pipe is broken, worn out fly screen

Install new vent pipe and replace the fly screen


Technical drawings

Drawings PL1 to PL13 can be adapted by the addition of a vent pipe per drop hole and a ventilation panel over each door

Drawings VIP1, VIP2 (although these two designs do not have disabled access)

Bill of Quantities

BofQs for PL8, PL9 and PL10 can be adapted to become VIP latrines

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3.1.3 Double vault ventilated improved pit latrine

Name of technology

Double Vault Ventilated Improved pit latrine (DVVIPL)


The double vault latrine has two shallow pits, each with their own vent pipe but under only one superstructure. The cover slab has two-drop holes, one over each pit. Only one pit is used at a time. When the first one is full, its drop hole is covered and the second pit is used.

Fig 19. Double vault ventilated improved pit latrine

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O&M requirements










Replace entire slab




VIP latrine: Vent pipe is broken, worn out fly screen

Install new vent pipe and replace the fly screen


Technical drawings

DVVIP1 (boys)

Bill of Quantities

DVVIP1-BQ (boys)

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3.1.4 EcoSan latrine (double vault) - wet

Name of technology

EcoSan Latrine (double vault) - wet


The double-vault ecosan latrine consists of two watertight chambers (vaults) to collect faeces. Urine is collected separately as the contents of the vault have to be kept relatively dry. Urine and stabilized feacal matter are to be used as fertilizer.

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Fig 20. Ecosan (double vault) - wet

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O&M requirements


Ensuring material is appropriate for re-use

As the waste will be used as a fertilizer after it has become safe it is important that only feacal waste and organic matter goes into the pit

Care must be made to ensure no plastic or other materials such as sanitary towels enter the pit









Replace entire slab



Pit in use is full Close off the full pit and leave it closed for a minimum of one year

Open other pit for use

After a year without use, empty the full pit and keep closed until the second pit is full

Use the material from the first pit as fertilizer (it is safe after one year of leaving to stand)

When the second pit is full, close the second pit and revert to the full pit

Repeat the cycle Note: All school toilets should be designed to allow emptying


Technical drawings


Bill of Quantities


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3.1.5 Pour flush latrine (off set)

Name of technology

Pour flush latrine (off set)


This is a type of latrine which uses water to flush or convey faecal matter from a pedestal or squatting pan to a pit, 1-3 litres of water are enough to flush the contents. A pit located off-site. The pour flush latrine can have a single or twin pit.

Fig 21. Pour flush latrine (off set)

2

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O&M requirements










Replace entire slab



Blocked pipe Use flexible rod to unblock pipe and flush with water to wash blockage through into the pit

Soakaway pit is full Empty soakaway pit latrine if design allows Note: All school toilets should be designed to allow emptying


Technical drawings

PFL1

Bill of Quantities

PFL1-BQ

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3.1.6 Flush latrine with cistern

Name of technology

Flush latrine with cistern


Flush toilet is interchangeably used with water closet (WC). It is mostly a permanent and hygienic way of human excreta disposal. It requires a piped water supply with a constant supply of water to function properly and has higher maintenance requirements than a pit latrine. There is no smell due to the water seal.

Fig 22. Flush latrine with cistern

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O&M requirements










Replace entire slab



Blocked pipe Use flexible rod to unblock pipe and flush with water to wash blockage through into the pit

Soakaway pit is full Empty soakaway pit latrine if design allows Note: All school toilets should be designed to allow emptying


Cistern stops flushing water Check inside that the flushing mechanism is not broken – request a fundi to help repair if problem is not obvious

Rope or handle breaks Replace rope of handle with a new one

Technical drawings


Bill of Quantities


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3.1.7 Biogas-latrine

Name of technology

Biogas-latrine


Biogas-latrines are integrated units, consisting of ventilated improved pit latrines, with septic tanks attached. The septic tanks, which serve as bio-digesters, differ from normal septic tanks in that processing is carried out in an anaerobic environment. The treatment of waste is more thorough than in a normal septic tank, and there is an outlet for the biogas produced in the process which can be used for cooking.

Fig 23. Biogas-latrine

Technical drawings


Bill of Quantities


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3.2 Latrine block designs versus costs

The following three levels of option for the latrine block design are identified to be appropriate for use in schools. One option is going to be adopted from WEDC mode but it will need modification in order to make it child friendly e.g ensure that the facility can be used throughout the year (Urinal & hand washing facilities need to roofed, provide rainwater harvesting system). Other options can also be utilised such as: double vault and pour flush latrine may be adopted from EEPCO or the MOEVT designs with the latrines inside a building structure. All these have to meet the minimum standards as specified in the guideline. The WEDC model provides different cost options but ensures that each has a minimum standard of:

Safety (partially or fully lined pit and concrete slab)

Privacy with lockable doors and a privacy screen

Hand-washing with drainage, set at the exit from the unit

Urinal for boys or washing / bathing unit for girls

Accessibility for disabled children Using alternative materials: Note that in the case of the designs with mud walls, or burnt brick walls other alternatives can also be adopted with techniques used locally such as: Stabilised soils using local products such as:

Sand and clay

Straw, plan fibres

Wood ashes

Cow dung

Termite hills

Stabilised soils using manufactured stabilisers such as:

Lime and pozzolanas

Portland cement

Gypsum

Bitumen

Commercial soil stabilisers

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Table 2. Cost options for school latrines

Lower cost option Medium option

Higher cost option Reference

Where funds are limited The target minimum standard for Tanzania

Simple pit latrine with access for emptying

Modified WEDC design:

Partially or fully lined pit (PL1, 2, 3, 4)

Concrete slab (PL5, 6)

Mud walls, thatched roof – stablilised soil walls can also be used (PL7)

Natural materials for doors




Burnt brick walls – stabilised soil bricks could also be used (PL8, PL9)

Corrugated iron roof

Corrugated iron doors with wooden frame




Cement block walls (PL10)


Wooden panel doors

Drawings modified from WEDC original designs for the Tanzania context

VIP latrines with access for emptying

Modified WEDC design As above with addition of vent pipe with fly mesh and air vent above the door



Drawings modified from WEDC original designs for the Tanzania context

MOEVT VIP design:

Fully lined pit (VIP1, 2)

Cement block superstructure


Note – no disabled access included in the designs

MOEVT Infrastructure unit

Double vault VIP

EEPCO design:

Double vault VIP(DVVIP1)

Cement block or burnt brick walls

Concrete slab


EEPCO

Pour flush EEPCO designs:

Ceramic pour flush bowl

Cement block walls

Concrete floor


EEPCO

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Pour flush to pit latrine / septic tank / sewer

Cistern flush / water closet

MOEVT designs:

Water closet latrines inside the building structure

Disabled access latrine

MOEVT Infrastructure unit

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3.3 Lining materials for different ground conditions


Pit lining for different ground conditions


Pit lining techniques can be dry or mortar bond. Materials that can be used for lining include; stabilised blocks, burnt bricks, trapezoidal blocks, rocky blocks, stones, woven basket and cement blocks. Soil filled plastic sacks can also be used. Pits can be fully or partially lined.

Fig 24. Ring beam of burnt bricks and mortar and woven basket below

Fig 25. Rough stone lining

O&M requirements

Proper burning for burnt bricks is required while appropriate ratio and curing for the case of trapezoidal and cement blocks is needed.

Technical drawings

Included in latrine block designs – PL1, PL2, PL3, PL4.

Also refer to local expertise.

Bill of Quantities

Included in latrine block design Bill of Quantities. Also refer to local expertise.

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3.4 Pit emptying


Pit emptying


It is essential that all latrines should be designed for emptying with both an access hole and enough space for a suction tanker to reach the latrine. A latrine becomes much more cost effective when it can be emptied and is emptied on a regular basis.

If a latrine is not designed for emptying then once it is full the latrine will have to be abandoned.

Fig 26. Emptying a latrine with a gulper

Fig 27. Emptying a septic tank with a suction tanker

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O&M requirements

Good practice for pit emptying which is a critical part of operation and maintenance of a latrine is:

Design the pits for emptying – with an opening that can allow emptying by suction tanker, sludge gulper or by hand and also enough space to get a suction tanker near enough to the pit to be able to get the suction pipe in to the pit sludge.

If there is not enough space for a suction tanker then a portable sludge gulper can be used.

There is a need to know where the pit contents can be disposed of – this information can be obtained from the local government authority or municipal council.

Care must be taken to ensure safe handling of the sludge and those involved must wear protective clothes and practice good hygiene.

Community awareness and mobilisation should be undertaken for regular pit emptying.

Pits that are to be emptied will need to be fully lined to ensure pit stability.

Considerations for design what are being considered / trialled at present:

Design the pit to be smaller so that it requires more regular emptying so that the users get used to this process.

Having a sloping bottom to the pit to ensure that the sludge falls down to the lowest point under the access hole through which the pit is emptied.

Technical drawings

Emptying compartment has been included in all latrine block designs.

Bill of Quantities

N/A

46

3.5 Urinals


Urinals


A location where boys or girls can urinate and the urine is taken away via slopes or containers and pipes for disposal. The provision of urinals can reduce queues for toilets at breaks times. Water is needed to wash the urinals regularly to prevent smell.

Urinals can be provided for girls but only for younger girls who have not reached puberty.

Fig 28. Trough urinal - boys

Fig 29. Ceramic bowl urinal - boys

47

IMPORTANT NOTE – Girls urinals are only suitable for young girls pre-puberty

Fig 30. Girls urinal

O&M requirements


Smelling Clean at least twice a day with water and detergent powder using a soft brush with a long handle. The detergent powder can be sprinkled in the evening to be washed in the next day.

Clogging of pipes Remove the sieve over the drainpipe and insert a flexible, thin stick to push the blockage through. This can also be done from the soak-away end. All solid waste around the urinal areas must be collected properly and disposed off in the school waste pit.

Ensuring good practice in use of the urinals

Teach pupils and students toilet manners.

Technical drawings

Included in toilet block designs for boys – PL2, PL3, PL5, PL7, PL8, PL11, VIP1, WC1

Urinals can also be for girls

Bill of Quantities

Included with toilet block designs – PL7, PL8

48

3.6 Girl friendly designs, bathing units or girls hygiene units


Girl friendly designs, bathing units or girls hygiene units


Girls at school have particular needs. These include:

a) Safety and security when using the latrine to prevent sexual attack

b) Privacy when using the latrine

c) Facilities which allow the girl to deal with menstruation with privacy and dignity

Examples of girl friendly design features include:

a) Privacy screen in front of the doors

b) Lockable doors from the inside

c) Water available at the latrine for personal hygiene – ideally it is best to have water inside the latrine to aid privacy during menses

d) Hand-washing and water available in private area (for cleaning blood from hands if soiled)

e) Private room or area for washing or bathing in the latrine block

f) Somewhere to discretely dispose of sanitary pads or to wash soiled menstrual cloths – the containers should not be see through and the bin should have a lid (this will also be useful for when the bin is moved for emptying)

Fig 31. Girls hygiene unit / room

49

O&M requirements


Sanitary bins need emptying Sanitary refuse bins need to be emptied on a regular basis and the waste handled carefully to prevent contact with the menstrual blood.

Sanitary towels and old cloth must be disposed of appropriately. Refer to section 3.9.2.

Floor needs cleaning Floors to be cleaned with detergent at least once a day and waste water washed into drain.

Water container empty Fill the water container on a regular basis

Clogging of pipes Remove the sieve over the drainpipe and insert a flexible, thin stick to push the blockage through. This can also be done from the soak-away end. All solid waste around the urinal areas must be collected properly and disposed off in the school waste pit.

Technical drawings

Included in standard latrine block designs – PL1, PL4, PL6, PL9, PL10

Bill of Quantities

Included with standard latrine block designs – PL9-BQ, PL10-BQ

50

3.7 Accessibility to sanitation for children and adults with disabilities

3.7.1 Pathways and ramps

Dimensions and other specifications

2.1

Min width: 1.20 m

Max gradient: 1:20 (5%)

Min length of landing: 1.20 m

In between landing: every ten metres

Handrails (70 and 90 cm height) or curbs (5 cm height)

Firm, even and slip-resistant surface

Ground surface indicators (e.g. colour contrast) at the top and bottom of the ramp with minimum width of 60 cm

Adequate water drainage

Barrier free

Picture: CBM

Fig 32. Acceptable slopes for wheelchair users

51

Low cost option

Compacted soil Bricks/stones

Fig 33. Slope made of compacted soil / bricks / stones

52

Medium cost option

Concrete ramp with curbs or handrails on the sides

Fig 34. Path with curbs and tactile strips to assist a child or adult who are blind

Fig 35. Concrete ramp with curbs

53

Fig 36. Technical drawing of handrails for improving accessibility inside latrines

54

Higher cost option

Concrete ramp with resting stages and hand-rails

Fig 37. Concrete ramp with hand-rails and resting platforms

55

3.7.2 Doors

Dimensions and other specifications

A level platform (“landing”) outside the door, minimum length: 120 cm

Minimum door width: 90 cm

Door opening outside

Fig 38. Door handrail for ease of opening

56

Handles / locks Pull handle on the inside needed for closing (see photo above)

Height of the pull handle: between 0.90 and 1.20 m from the floor

Large hole and light materials

Fig 39. Easy grip door handle and lock

57

3.7.3 Layout and handrails

Dimensions There must be a

turning circle of 150cm inside the latrine Minimum internal dimensions 1.5m x 1.8m with the seat to the left side near the back wall Handrails at 70 and 90 cm, on right hand side when seated on the toilet

Fig 40. Concrete block and wooden seat with handrail options for ease of transfer to and from the latrine seat

58

Fig 41. Layout of the minimum dimensions for an accessible latrine unit

59

3.7.4 Latrine seats

Low cost option (approx cost = 20,000)

Cement blocks with wooden top:

Width of seat: 50 cm

Depth of seat: 40 cm

Height of blocks: 35 cm

Hole: 25x10 cm

Good finishing required for durability and hygiene reasons

Fig 42. Concrete block for use in a latrine and a wooden seat

60

Medium cost option (approx cost = 48,000 TShs)

Moveable wooden stool:

Different dimensions for children and adults


Larger stool:

Seat height above ground = 500 mm

Seat size = 420 mm x 420 mm

Smaller stool:

Seat height above ground = 375 mm


Item No. Description Quantity Unit Rate

Total (TSHS) Dar es Salaam cost

1 Timber

1'' x 12'' x 8 ft 1 PC 25,000 25,000

2 Nail 2'' 0.5 Kg 4,800 2,400

3 Glue 0.25 Litre 4,000 1,000

4 Machine works 1 Lumpsum 5,000 5,000

5 Finishing

Msasa 0.5 M 3,000 1,500

Varnish 0.5 litre 6,000 3,000

6 Labour charge

10,000

TOTAL

47,900

Fig 43. Wooden stools for use in a latrine with bill of quantities

61

Fig 44. Technical drawing of large wooden stool for use in a latrine

Fig 45. Technical drawing of a small wooden stool for use in a latrine

62

Medium cost option (approx cost = 78,000)

Moveable chair with armrests:


Larger chair:

Seat height = 500mm

Seat size = 420mm x 420mm

Backrest = 500mm high

Smaller chair:

Seat height = 375 mm


Backrest = 320 mm high

Seat – child and adult - Mninga wood

Item No. Description

Quantity Unit Rate

Total (TShs) Dar es Salaam

cost

1 Timber

1'' x 12'' x 10 ft 1 PC 30,000 30,000

2'' X 6'' X 7 ft 1 PC 20,000 20,000

2 Nail 2'' 0.5 Kg 4,800 2,400

3 Glue 0.25 Litre 4,000 1,000

4 Machine works 1 Lump sum 5,000 5,000

5 Finishing

-

Msasa 0.5 M 3,000 1,500

Varnish 0.5 litre 6,000.00 3,000

6 Labour charge

15,000

TOTAL

77,900

Fig 46. Wooden seat for use in a latrine with bill of quantities

63

Fig 47. Technical drawing for a large wooden chair for use in a latrine

Fig 48. Technical drawing for a small wooden chair for use in a latrine

64

3.8 Technical options for hand-washing


Tippy tap, water jars and hand-washing basins


Water Jars.

This refers to water jars made of ferro-cement or any other materials. Alternatively PVC tank such as SIM tank can be used, the tanks should collect water from toilet roof; during dry season provision for refilling should be made by asking pupils to bring water from home. Otherwise there should be a connection between the main school rain water tank and the jars at the toilet.

Hand water facilities should be a channel basin with multiple taps using push cork. Hand washing facilities should also be available for children with disabilities.

Soap (preferably liquid soap) should be made available. Water from hand washing channel/basin should be drained to garden

Tippy taps

Tippy taps can be made of calabash/Kibuyu or plastic container hanged in wooden poles with a paddle joined in a rope. Soap contained should be part of tippy tap.

Fig 49. Multiple tippy taps with liquid soap for hand-washing in schools

65

Ferrocement hand-washing jar connected to rainwater

SIM tank connected to rainwater

Fig 50. Hand-washing from a rainwater harvesting ferrocement hand-washing jar next to the latrine

Fig 51. Hand-washing from a SIM tank rainwater harvesting tank next to the latrine

66

Hand-washing sinks

Fig 52. Concrete hand-washing sink

Taps

Fig 53. Tap designs

O&M requirements

Repair the damaged parts/fittings

Clean the tank and check the tap

Replace the worn out parts

If vandalised replace the facility Keep the soakage pit clean and clear from silt

Technical drawings

HW1, HW2, HW3, HW4

Bill of Quantities

HW1-BQ, HW2-BQ, HW3-BQ, HW4-BQ

67

3.9 Technical options for solid waste disposal & sanitary pad disposal

3.9.1 Waste collection units and waste pits

The solid waste storage facilities recommended for school include standards dust bins, improvised bins, waste pits and collection point. The solid waste storage and disposal facilities may include:

Plastic containers of different colours and capacities (old or new)

Aluminium or metal containers (old or new)

Improvised containers

Waste pits.


Plastic, aluminium containers and waste pits


Plastic and aluminium containers are manufactured by industries with capacities ranging from 20 litres to 60 litres. The containers will be of different colours to help the sorting processes at source. The containers sizes to be used will depend on the type and solid waste generated by each school. Moreover, the container sizes will depend on the collection frequency. The waste pits are dug on ground at the school surroundings can be used for both storage and final disposal especially for organic solid waste.

Fig 54. Metal bucket with lid

Fig 55. Wicker basket with lid

68

Fig 56. Plastic bin

Fig 57. Plastic bucket

Fig 58. Pedal bin

Fig 59. Waste collection unit above ground

Fig 60. Waste collection pit for organic materials below ground

69

Fig 61. Waste pit for burial of organic waste

3

O&M requirements

Appropriate containers sizes and materials should be used. Containers should emptied regularly and washed / cleaned with soap.

Solid waste can be burnt in waste pits before they are covered with a layer of soil to prevent smell and flies.

Worn out and stolen bins should be replaced.

Students have to be taught solid waste sorting at source and all dust been should be thoroughly covered.

Technical drawings

Not provided

Bill of Quantities

Not provided

70

3.9.2 Disposal of sanitary pads

Name of the technology Disposal pit or small drum incinerator

Brief description of the technology This a specifically designed pit constructed for the purpose of keeping pads similar to placenta pit used in health facilities. The pit should be constructed with cement blocks, burnt bricks or stones with permeable base to allow seepage to infiltrate. It should be covered with a concrete slab provided with drop hole.

Alternatively a small drum incinerator similar to those used in emergencies for health facilities, can be used. A small drum incinerator must be well fenced to keep pupils away as they become very hot.

Fig 62. Protected waste pit

Fig 63. Drum incinerator – must be fenced

O&M requirements

Ensure that pupils (girls) are taught about the appropriate disposal of sanitary pads.

The sanitary pits should be water tight and have a special cover to prevent animals and birds to scavenge the disposed wastes.

If a drum incinerator is used it to be kept fenced, the waste burnt every day or every few days depending on the volume and the ash removed regularly.

Technical drawings

To be added later

Bill of Quantities

To be added later

71

3.10 School kitchens and dining areas

Name of the technology Hygienic kitchen and dining areas

Brief description of the technology Where schools provide food for children and staff the good hygiene of the school kitchens must be ensured and good food handling practices ensured at all times.

The school kitchen and dining hall should meet minimum hygienic standards (e.g. cleanable floor, adequate water supply, ventilation, free from vermin and rodents, separate storage of raw and cooked food, etc).

Location of the kitchen should be away from sources of contamination like latrines, disposal sites, otherwise there should at least be an intervening ventilated space.

Water supply and soap for regular hand-washing by the cooking staff must be near the kitchen area.

A bench or rack should be provided for the safe drying and storage of cooking pots and utensils.

Wherever possible a dining area with seats and tables with washable surfaces should be provided for students to eat their lunches.

Fig 64. Washable floor and drying rack in a school kitchen

72

Fig 65. Seat and washable table in a dining area

O&M requirements

Operation and maintenance of kitchen and dining areas:

Kitchen surfaces should be cleaned with detergent at least once a day.

The water should either be poured into a pit or into a unit with a simple grease trap to catch the solids and grease.

The disposal area for waste water which has food pieces within it must be covered with soil or cleaned on a regular basis to prevent vermin and bad smells.

Tables, seats and floors should also be cleaned daily with water and detergent.

Drainage areas from water points must also be kept free flowing and clean and hygienic.

Maintain a clean and hygienic serving area.

Maintain a clean and hygienic clean-up area, which is removed from food preparation.

Food preparation and handling:

If the school provides food, it should be prepared with safe water and by a cook who practices hand washing with soap before preparing and serving food.

Kitchen staffs that are having infectious diseases must not handle food.

All food handlers should undergo medical examinations every six months and

73

those who are found to be sick should be treated and recovery ensured before resuming their duties.

Food should be handled and prepared with utmost cleanliness: school kitchens should be cleanable and meet minimum hygienic standards.

Kitchen utensils must be washed with warm water and detergent and dried safely.

Contact between raw foodstuffs and cooked food must be avoided.

Food should be cooked thoroughly and stored at a safe temperature prior to serving.

Safe water for washing fresh raw ingredients should be used.

Particular care to only provide hot food is needed during cholera outbreaks as poor food hygiene is a major means of transmission.

Students may be involved in serving and clean-up.

Minimise the number of hands contacting food and utensils (in the transferring of food between the cook and the students).

Technical drawings

Not provided

Bill of Quantities

Not provided

74

Appendix 1 – List of tables and figures

Tables

Table 1. Point of use water treatment options for schools ............................................................... 20

Table 2. Cost options for school latrines ........................................................................................... 41

Figures

Fig 1. Rainwater harvesting ............................................................................................................ 9

Fig 2. Rainwater harvesting gutters ............................................................................................. 10

Fig 3. Shallow well with handpump .............................................................................................. 11

Fig 4. Standpipe ............................................................................................................................ 12

Fig 5. Protected spring .................................................................................................................. 13

Fig 6. Borehole, raised tank and pump house .............................................................................. 14

Fig 7. Charco dam with fencing, stone filter and domestic point ................................................. 15

Fig 8. Shallow well with handpump, fencing and drainage .......................................................... 16

Fig 9. Handpump with seat and wheelchair access ...................................................................... 18

Fig 10. Tap designs that are easier to use with limited grip............................................................ 18

Fig 11. Ceramic bucket filter............................................................................................................ 22

Fig 12. Boiling .................................................................................................................................. 22

Fig 13. Point of use water chlorination ........................................................................................... 23

Fig 14. Syphon filter......................................................................................................................... 23

Fig 15. Biosand filter ....................................................................................................................... 24

Fig 16. Ceramic candle filter ............................................................................................................ 24

Fig 17. Improved pit latrine with hand-washing ............................................................................. 26

Fig 18. Ventilated improved pit latrine with hand-washing ............................................................ 29

Fig 19. Double vault ventilated improved pit latrine ....................................................................... 31

Fig 20. Ecosan (double vault) - wet ................................................................................................. 33

Fig 21. Pour flush latrine (off set) .................................................................................................... 35

Fig 22. Flush latrine with cistern ..................................................................................................... 37

Fig 23. Biogas-latrine ...................................................................................................................... 39

Fig 24. Ring beam of burnt bricks and mortar and woven basket below ........................................ 43

Fig 25. Rough stone lining ............................................................................................................... 43

Fig 26. Emptying a latrine with a gulper ......................................................................................... 44

Fig 27. Emptying a septic tank with a suction tanker ..................................................................... 44

75

Fig 28. Trough urinal - boys ............................................................................................................. 46

Fig 29. Ceramic bowl urinal - boys .................................................................................................. 46

Fig 30. Girls urinal ........................................................................................................................... 47

Fig 31. Girls hygiene unit / room ..................................................................................................... 48

Fig 32. Acceptable slopes for wheelchair users ............................................................................... 50

Fig 33. Slope made of compacted soil / bricks / stones................................................................... 51

Fig 34. Path with curbs and tactile strips to assist a child or adult who are blind .......................... 52

Fig 35. Concrete ramp with curbs ................................................................................................... 52

Fig 36. Technical drawing of handrails for improving accessibility inside latrines .......................... 53

Fig 37. Concrete ramp with hand-rails and resting platforms ........................................................ 54

Fig 38. Door handrail for ease of opening ...................................................................................... 55

Fig 39. Easy grip door handle and lock ............................................................................................ 56

Fig 40 Concrete block and wooden seat with handrail options for ease of transfer to and from the latrine seat .......................................................................................................................... 57

Fig 41. Layout of the minimum dimensions for an accessible latrine unit ...................................... 58

Fig 42 Concrete block for use in a latrine and a wooden seat. ....................................................... 59

Fig 43. Wooden stools for use in a latrine with bill of quantities .................................................... 60

Fig 44. Technical drawing of large wooden stool for use in a latrine .............................................. 61

Fig 45. Technical drawing of a small wooden stool for use in a latrine .......................................... 61

Fig 46. Wooden seat for use in a latrine with bill of quantities ....................................................... 62

Fig 47 Technical drawing for a large wooden chair for use in a latrine .......................................... 63

Fig 48 Technical drawing for a small wooden chair for use in a latrine. ........................................ 63

Fig 49. Multiple tippy taps with liquid soap for hand-washing in schools ...................................... 64

Fig 50. Hand-washing from a rainwater harvesting ferrocement hand-washing jar next to the latrine .................................................................................................................................. 65

Fig 51. Hand-washing from a SIM tank rainwater harvesting tank next to the latrine .................. 65

Fig 52. Concrete hand-washing sink ................................................................................................ 66

Fig 53. Tap designs .......................................................................................................................... 66

Fig 54. Metal bucket with lid ........................................................................................................... 67

Fig 55. Wicker basket with lid ......................................................................................................... 67

Fig 56. Plastic bin ............................................................................................................................ 68

Fig 57. Plastic bucket ....................................................................................................................... 68

Fig 58. Pedal bin .............................................................................................................................. 68

Fig 59. Waste collection unit above ground .................................................................................... 68

Fig 60. Waste collection pit for organic materials below ground ................................................... 68

Fig 61. Waste pit for burial of organic waste .................................................................................. 69

Fig 62. Protected waste pit ............................................................................................................. 70

Fig 63. Drum incinerator – must be fenced ..................................................................................... 70

Fig 64. Washable floor and drying rack in a school kitchen ............................................................ 71

76

Fig 65. Seat and washable table in a dining area ........................................................................... 72

Documents

United Republic of Tanzania - Wash In Schoolswashinschoolsmapping.com/wengine/wp-content/uploads/2015/10/... · PL8-BQ Bill of quantity – for burnt brick superstructure (boys) with