Operation and Maintenance manual for VIP latrines and rainwater harvesting systems in schools
The manual was written in reference to the Safety Standard Manual for Schools in Kenya issued by the Ministry of Education in 2008 and is intended for the use of the Board of Management, teachers and caretakers in Kericho. Ventilated Improved Pit Latrines 1. Components of a Ventilated Improved Pit (VIP) latrine A VIP latrine consists of three major parts: A hole in the ground the pit in which urine and faeces are collected; The latrine slab with a squat-hole and foot rests the cover of the pit on which the user stands when using the latrine; The super structure or shelter which is also known as an outhouse that provides privacy and protection from sun and rain. 2. Why is a VIP latrine special compared to a common latrine A VIP latrine is a pit latrine that has been fitted with a vent pipe and a fly screen. Through these two parts smell will be avoided. Air circulates down the squat hole into the pit and up through the vent pipe and takes with it the bad smell. Inside a VIP latrine it is quite dark. Flies that might enter the latrine through the door or the air vent will be attracted to the light in the vent pipe where they are trapped against the fly screen and will eventually fall back into the pit and die. In this way they cannot leave the latrine and carry with them faeces that contain germs that can transmit diseases to people. The illustration below shows all parts of a VIP latrine and how it works. 2 / 17
3. Use of latrines VIP latrines in schools often come as blocks of more than one. They are usually separate for girls, boys and teachers. As with all other buildings on the school compound the latrines need to be used carefully so they can last for a long time. And similar to all other buildings the latrines need to be kept clean. Ideally, the squat hole is closed with a cover. When using the latrine, the squat hole cover should be removed and the feet should be placed on the foot rests. When leaving the latrine nothing should be left on the latrine floor if it does than the student or teacher should immediately clear the floor using water and a brush. All dirt should be brushed into the squat hole. Before leaving the latrine the squat hole cover needs to be put back on the squat hole. No cleaning materials other than (toilet) paper and no rubbish should be thrown into the pit. The same is true for sanitary pads which should also not be thrown into the pit but be wrapped and disposed off in a special bin. Using the pit as a rubbish bin will fill it up too quickly and can block the pipes when the pit is emptied through a pump. All the same is true also for the urinals for girls and boys keeping them clean and not leaving any rubbish behind that can eventually block the urinal drain is important. Doors and gates need to be closed carefully not to damage them. It is good practice that older children assist a younger child to use the latrines by showing them how to use them properly, especially at the beginning of each new school year for the students of class 1 and younger children if the school has a section for ECDE. 3 / 17
4. Operation and maintenance of latrines To keep the latrines clean and usable for a long time, some extra work needs to be done additionally to what is mentioned in the chapter above. These tasks are called operation. The superstructure and slab need to be regularly cleaned with water and disinfectant to remove any faeces and urine. Appropriate anal cleaning materials should be available for the latrine users at all times, such as toilet paper. All tasks that fall under day-to-day operation are listed in the next table. Responsibilities and schedule for operation of the latrines Task Who is responsible? Frequency Tools and equipment needed Clean all latrine floors and urinals Empty sanitary waste bins Check the cleanliness of the latrines and urinals including waste bins (and emptied) and that squat hole covers are there Check whether there is toilet paper available all times Purchase of toilet paper Check that all doors are lockable Clean the fly screen and the inside of the vent To keep the latrines usable for a long time the structures need to be maintained. As a first step all parts of the latrines need to be checked regularly. Depending on what you find during the checks some parts might need repair or replacement. Through regular inspections it will be clear which parts need attention. The table below will help to know what to check, by whom and when. It also shows what repairs can be done by the caretaker and for which work external help is needed, e.g. the de-sludging. 4 / 17
Responsibilities and schedule for maintenance of the latrines Task Who is responsible? Frequency Materials and spare parts needed Repair of doors if they do not lock Tools and equipment needed If vent pipe is blocked pour water down through it to remove spider webs Check the condition of the super structure for cracks on the walls and the floors Repair the cracks in the walls and floor Check the condition of the roof and gutters Repair roof and gutters Check that the vent pipe and fly screen are intact 5 / 17
Task Who is responsible? Frequency Materials and spare parts Tools and equipment Repair vent pipe and fly screen Check the foundation of the latrine Repair the foundation of the latrine Check any loose soil around the foundation of the latrine Refill and compact soil around the latrine foundation Check whether latrine pit is full De-sludging of latrine pits A special note on the management of the pit When the pit of a latrine is full, it can no longer be used. The time it takes to fill the pit depends on the size of the pit and the number of users. To avoid that the latrine cannot be used anymore, the pit needs to be emptied. The emptying of a pit can either be done manually with shovels and buckets, with a manually powered pump or with a motorized pumps mounted on a truck that carries a tank to transport the sludge. For the faecal sludge to be pumpable, usually water needs to be added to the pit and the content needs to be stirred up. This is part of the pumping service. It is recommended to use the commercial pump service if available. The faecal sludge will be transported by road to either a sewage treatment facility or to be composted safely elsewhere. There are numerous licensed waste hauling companies providing such service in bigger towns such as Kericho. To reduce the volume of faeces in the pit, and to reduce odour and fly problems in the latrine, a range of commercial products are available. These pit additives are composed of microorganisms that trigger chemical reactions and speed up a decomposition process. Cheap and effective alternatives are wood ash or sawdust that are added to the sludge regularly 6 / 17
5. Trouble shooting for latrines and hand washing stations Although regular checks are carried out, problems that can cause the latrines to not properly function can occur. The following table lists these problems and possible solutions. Problem Probable cause Possible solution Fluids stagnating on the latrine floor Floor constructed not sloping towards the squatting hole Add another floor layer, consult with artisan to know which materials are needed Foul odours in the latrines at certain times of the day (usually early morning) No air circulation if outside air temperature is colder than the air in the pit Put all covers on the squat hole at the end of each school day Pit nearly full Pit needs to be emptied Rainwater tank for hand washing does not fill up Blockage in down pipe Remove blockage by cleaning or replacing filter of the inlet pot Gutter is damaged or sagging Leaky tank Check levels of gutters and correct if required, add more brackets to lift gutters Check for leaks and repair or replace tank Leaky valve or tap Check for leaks and repair or replace valve or tap; Monitor usage of the valve or tap 6. Operation and maintenance of hand washing facilities The use of hand washing facilities is quite simple. It involves opening the lid, refilling the container, closing the lid, opening and closing the valve or tap. When washing hands, water should be taken only from the valve or tap. Maintenance on the other hand involves regular cleaning of the container with water and disinfectant to remove any dirt, repairing leakages/cracks, unblocking drains and replacing damaged components. 7 / 17
Schedule and responsibilities for operation and maintenance of the hand washing facilities Activity Who is responsible? Frequency Materials & spare parts needed Tools & equipment needed Clean surrounding area of hand washing facilities Check the cleanliness of surrounding area of hand washing containers Refill hand washing containers Check whether hand washing containers are refilled Test whether taps are functioning and not leaking Repair of tap in case of leakage Check whether there is soap next to the hand washing containers Refill soap for hand washing containers Purchase soap for hand washing containers Clean and disinfect containers 8 / 17
7. Trouble shouting for hand washing facilities Although regular checks are carried out, problems that can cause the hand washing facilities to not properly function can occur. The following table lists these problems and possible solutions. Problem Probable cause Possible solution Cracked or leaking tank or container Poor workmanship Inadequate operation and maintenance Repair the tank or container Contaminated tank or container Poor hand washing method Proper hand washing method Corroded tank Low ph value (acidic water) Neutralise the water with rainwater Damaged tap or valve Poor material of tap Wrong method of operation Replace the tap with high quality manufacture 8. Essential of tools and spare parts for operation and maintenance for latrines and hand washing facilities In order to operate and maintain latrines and hand washing facilities a few items and tools are needed. Some might be already in the school to keep the class rooms and offices clean and carry out repairs. Others might need to be bought especially. Broom: shop bought to clean all surfaces, especially latrine floors and surrounding area of hand washing facilities. Bucket: to fetch water for wet cleaning with brushes and brooms. Ladder: can be self-made or shop bought to check blockages in the vent pipe, down pipes, gutters, roofs and so on. Hinges: to repair doors. Vent cap: might need to be replaced when broken. Taps for hand washing facility: if leakage cannot be repaired, tap will need to be replaced. Gutters: it is good to have always a few pieces in stock to be able to replace them if needed. All items, tools and spare parts can usually be bought from hardware shops. In Kericho you will find the spare parts at the shops of Mutai Hardware, Visnuu Hardware and Gokul Hardware. Rainwater Harvesting Systems 9. What is rainwater harvesting Rainwater harvesting is a technique used for collecting, storing and using rainwater. The water can either be collected from roofs or surface runoff, e.g. hills or rocks. In rooftop harvesting, the rainwater is collected from the roof of the building, e.g. a class room. The water will be stored in an open or closed tank. This method has a relatively low investment cost, depending on the kind and size of the storage tank. 9 / 17
Advantages of water supply from rainwater harvesting systems at schools: Apart from the initial investment cost, the provisions for operation and maintenance are relatively low; It reduces the burden of children having to fetch water from unsafe sources and to bring drinking water to school daily; It can provide supplementary water for other purposes such as irrigation for school gardens; 10. Components of a roof catchment rainwater harvesting system The system consists of six major parts: Roof catchment: the surface that receives rainfall directly; Gutters and down pipe: transport water from the catchment to the storage; Brackets hold gutter, fixed to facia board; First flush: acts as filter, preventing water from the roof catchment that might be contaminated especially after it has not rained for several days from entering the storage tank; Inlet pot with filter that is placed at the top of the storage tank to prevent particles, leaves and other bigger objects from entering the storage tank; Storage tank: where the water is kept before it is used, fitted with a tap to access water. 10 / 17
11. Quality of water from a roof catchment rainwater harvesting system Rainwater is relatively free from impurities except those picked up by rain from the atmosphere. Wind-blown dirt, leaves, faecal droppings from birds and animals, insects and contaminated litter on the roof can be sources of contamination of rainwater. The quality of rainwater may deteriorate during harvesting, storage and use, especially if stored in open tanks. It is important to follow hygiene measures during storage of water and when drawing water from the tank or at the point of use to avoid health risks. Risks can also be minimized by good design and operation and maintenance. Welldesigned rainwater harvesting systems with clean catchments and storage tanks supported by good hygiene at point of use can offer drinking-water with very low health risks. To minimise the risk from rainwater harvested from roofs it is recommended to: Include and use a first-flush filter to regularly drain the water from the roof after dirt might have settled there; Involve the Ministry of Health for a regular monitoring of the water quality; The following water treatment methods can be carried out in addition to provide safe drinking water at the point of consumption: filtration and chlorination. 12. Operation and maintenance of roof catchment rainwater harvesting system Rainwater harvesting systems require few skills and little supervision to operate. Major concerns are the prevention of contamination of the tank during construction and while it is being refilled during a rainfall. If the water is to be used for drinking purposes, filtration and chlorination or disinfection by other means (e.g. boiling) is recommended. The following should be considered in the operation of rainwater harvesting systems: A procedure for eliminating the "foul flush" after a long dry spell deserves particular attention. The first 10 minutes of each rainfall should be diverted through the first flush to not enter the storage tank since they are most likely to contain undesirable materials which have accumulated on the roof between rainfalls. 11 / 17
Responsibilities and schedule for operation of roof catchment rainwater harvesting system Task Who is responsible? Frequency Tools and equipment Check cleanliness of area around tank and draw points/ taps Supervise the cleaning of the tap stand and the areas around tanks Check that taps can be opened and closed easily Use first flush to flush out water of the first rains Check that no leaked water from tank is collecting in puddles around tank The following guidelines should be considered in the maintenance of rainwater harvesting systems: Gutters and downpipes need to be periodically inspected and cleaned carefully. The storage tank should be checked and cleaned periodically. All tanks need cleaning; this applies to both plastic and masonry tanks. Use of a chlorine solution is recommended for cleaning, followed by thorough rinsing. These steps have to be taken to properly clean the storage tank. It is recommended that this is carried out once per term. 1. Disconnect the down pipe; 2. Empty storage tank by opening washout (masonry tank only) to about a quarter of the height; 3. Use ladder to step up the storage tank; 4. Step on water tank; 5. Open tank man-hole cover and put ladder in the tank; 6. Enter tank with two persons; 7. Close the washout; 8. Clean the walls and floor of the tank with broom and brush, keep man-hole cover open; 9. When tank has been cleaned completely, open the washout and rinse tank with buckets of clean water, keep man-hole cover open; 10. Close the man-hole cover and lock it with a padlock; 11. Reconnect down pipe. 12 / 17
Responsibilities and schedule for maintenance of roof catchment rainwater harvesting system Activity Who is responsible? Frequency Materials & spare parts needed Tools & equipment needed Check the gutters for dust, debris, leaves, other materials e.g. polythene papers Cleaning of guttering system Check the gutters for damages Check fascia board Repair or replace fascia board Repair or replace gutters Checking of the inlet pot Clean inlet pot 13 / 17
Activity Who is responsible? Frequency Materials & spare parts needed Tools & equipment needed Check filter on the overflow and breathers pipes (for masonry tanks only) Replace fly-screen on the overflow and breathers pipes (for masonry tanks only) Cleaning of the tank Repair of cracks/leakages of superstructure of masonry tank Check functionality of man-hole cover Repair or replace man-hole cover Check taps for functionality Repair or replace taps 14 / 17
Activity Who is responsible? Frequency Materials & spare parts needed Tools & equipment needed Repair of the leaking /faulty pipe fittings such as gate valve or tap Check pipes and valves for damages and leakages 15 / 17
13. Trouble shooting for roof catchment rainwater harvesting system Although regular checks are carried out, problems that can cause the rainwater harvesting system to not properly function can occur. The following table lists these problems and possible solutions. Problem Probable cause Possible solution Water does not enter tank No water in tank Water does not last long after end of rains Smelly water Blockage in down pipe Gutter is not installed at a gradient to allow water to flow to the tank Gutter sags Leaky tap Leaky tank Storage volume is low compared to consumption Organic matter in the tank decomposing Remove blockage, Clean or replace filter of the inlet pot Check levels on gutter and reset levels if required Add more brackets on the gutter Check for leaks and repair Monitor usage Regulate consumption by locking tap Provide additional storage if more water can be harvested; However, check whether tanks usually overflow. If not, then additional roof area and storage is required. Drain tank and clean tank A special note on the drinking water containers In some cases, the water will need to be treated before drinking to remove particulate matter (e.g. by filtering or chlorination). Disinfection with chlorine can easily be learned and needs to be done strictly in accordance to the prescriptions on the used product. Chlorine-producing chemicals should be stored in a cool, dry place, and care should be taken not to get any of the chemicals in the eyes or on clothes. Apart from cleaning and occasional replacement of containers and utensils, no maintenance is needed. The chlorine solution or aqua tablet should be organised by the Board of Management. 16 / 17
14. Essential of tools and spare parts for operation and maintenance for rainwater harvesting systems Tools and Equipment Use 24 pipe wrench Tightening or loosening 1 to 2 outlet of inlet pipes 36 pipe wrench Tightening or loosening 3 to 4 outlet of inlet pipes and its feeding Screw driver set Adjusting screws Broom, buckets, hard brush and hoes Cleaning the catchment surface, tanks, tap stands and troughs Shovel Cleaning the catchment surface, tanks and man-holes Ladder Getting on top of the tank to check on water level or access man hole to clean tank Die stock Pipe treading Spare parts that the schools should always stock: Tap washers, mesh, tap, spare gutter pieces. All items, tools and spare parts can usually be bought from hardware shops. In Kericho, you will find the spare parts at the shops of Mutai Hardware, Visnuu Hardware and Gokul Hardware. 17 / 17