About UNEP
United Nations Environment Programme
Division of Technology, Industry and Economics
top image
space space space
Newsletter and Technical Publications
<International Source Book On Environmentally Sound Technologies
for Wastewater and Stormwater Management>

8.11 Case studies (Topic k)

The following two case studies demonstrate the use of on-site deposal methods that are most commonly used in the Region as well as composting toilets that are currently being trialed. Both studies were commissioned by SOPAC.

8.11.1 Case Study 1: Sanitation in the Federated States of Micronesia


In the 1970's the "benjo" Erepresented the state of the art in sanitary facilities in Micronesia. There were two types: over-water and over-land. The over-water benjo was the most conspicuous and often desecrated an otherwise pristine beach. It consisted of a small enclosure (a privy) with a hole in the floor elevated on poles over the intertidal zone. One would get to this facility by negotiating various types of cat-walks (not always an easy task for the new comer!). At low tide, the mess below these facilities was in plain view. At high tide, one was lucky if it got washed away. The bay in Colonia, Yap, was affectionately called "Benjo Bay" because of the prevalence of these facilities. Similar facilities could be found over rivers (even up-stream of bathing areas) and in mangroves (where there is little or no movement of the water). The over-land benjo was essentially an unimproved pit latrine --- little more than a hole in the ground with a house over it. The user of these benjos would wish he could fly into and out of them and perform his mission without touching anything. In many of the remote atoll islands, there were no toilet facilities at all. The beach or bush were the bath room.

In 1983 a cholera epidemic occurred in Chuuk. Some people say it was a blessing in disguise because it opened people’s eyes to the possible consequences of the prevailing sanitary practices. As a result of the epidemic, an effort was made to outlaw benjos of all types and a massive program of building water-sealed toilets in the remote areas was undertaken. Hundreds of them were built such that every household that wanted one could have one. The Chuuk State Rural Sanitation Program by means of aid from the U.S. government provided the materials for the construction of these facilities. In the district centre, a house-sewer connection program was implemented. Although the epidemic was confined to Chuuk, other parts of Micronesia took measures to improve the sanitary facilities on their islands as well.

Today, more than a decade later, it is interesting to observe the state of affairs with respect to toilet facilities throughout Micronesia. To be sure, the classic over-water benjo no longer exists. Has the situation improved? What is the status of all those water-sealed toilets that were installed? Are other types of sanitary facilities being used? This report attempts to answer these and other questions. First, some cultural factors are presented that are relevant to toilet use. Then, three types of toilets are discussed with particular attention being paid to their water requirements, their potential for polluting groundwater, and their cultural acceptability.

Cultural factors

The outer islands of Yap are closely tied to Chuuk culturally and linguistically. Customs (and language, especially) have little to do with Yap proper; the state boundary is a political one. There is a continuum of customs that varies from the most traditional in the outer islands of Yap to the least traditional in the high islands of Chuuk proper. The degree to which the islands follow traditional practices probably varies something like what is indicated below:

most traditional
outer islands of Yap
Pattiw islands in Chuuk
Namonweito Atoll in Chuuk
Pafeng islands in Chuuk
Mortlock Islands in Chuuk
least traditional high lagoon islands in Chuuk proper

In a report to the UNDP concerning the design of sanitary facilities for Woleai Atoll in Yap State (Winter, 1991), the writer noted that:

"Three cultural factors exist that must be considered in the design of sanitary and bathing facilities for Woleai. The first is that brothers and sisters and, to a lesser extent, other males and females in the same household can not use the same toilet. Separate male and female toilets must be provided.The second is that water for toilet flushing must be available at the toilet. This is required because defecation is a very personal matter that is never announced verbally or, in the case of flushing a toilet, by carrying a bucket from a distant well to the toilet. If one desires to use a toilet, he simply leaves the group he is in without announcing the purpose of leaving. This especially applies to women in a mixed group. This factor necessitates pumping of groundwater from the source to the toilet facilities (because wells cannot be located adjacent to toilets). A third factor that may be of lesser importance is that men and women's clothing are hung in separate areas after washing. This implies a need for a separate male and female bathing/washing areas".

On the other hand, on the high islands of Chuuk lagoon, it would not be a problem for brothers and sisters to use the same toilet. However, a person (especially a woman) would be embarrassed to be seen carrying a bucket of water in the direction of a toilet. Like so many aspects of island cultures, it is easy for an outsider to make an assumption that is way off base and that will seriously jeopardize the chances of success of a project. Customs vary from island to island. All that can be said is that the person who intends to introduce any change in lifestyle should do his best to first seek out reactions to a proposed project from candid sources. Island people are very polite. Often, rather than give a contrary view, a view that could save a project from failure, people will simply be quiet.

The income level on some of the traditional islands is extremely low. It is certain that some families can not even afford the cost of toilet tissue. This is a consideration that must obviously be factored into any program directed at improving sanitary facilities. A response to this issue is that many water-sealed toilets can tolerate other types of paper. This solves the financial aspect of the problem. All that is needed is a source of paper!

Water-sealed toilets

Like a conventional flush toilet, a water-sealed toilet employs a water trap to seal or confine odours to the sewer pipe or waste storage area. Unlike a conventional toilet, flushing is done manually with a bucket of water. Generally speaking, the types of water-sealed toilets in use in Micronesia are functional but lack the aesthetic qualities of the toilet found in the modern home. However, compared to nothing --- the beach or bush --- they are certainly an improvement.

On the high islands of Chuuk, the water-sealed toilets promoted in the cholera era are gradually disappearing and are not being replaced. Some have been damaged by typhoons. In other cases, the 220 litre drum beneath the toilet has become filled. Many have simply deteriorated with age. According to the former director of the Chuuk Rural Sanitation Program, there is a feeling among the general population that it is the government’s responsibility to replace the toilets. Rather than reverting to use of the benjo, people are using the beach and the bush.

On one of the high islands of Chuuk, the writer has observed a new type of benjo --- although its designers probably would not like that designation. It consists of a neat hollow box-like foundation of rock in the intertidal area over which a privy is built. Although the wastes are not exposed to view, the intertidal waters are surely contaminated with them.

Even on Weno, the commercial and governmental centre of Chuuk, it is common at sunrise to see people of all ages, shapes, and sizes taking a walk to the beach or bush in the early morning. The reason is that, even though the area is sewered, toilets might not be functional and/or there is no city water with which to flush them.

On some of the atoll islands of Chuuk there essentially are no toilet facilities. This is at least true in Namonweito Atoll and in the Pattiw area. It is probably true in some other areas as well. Even though water-sealed toilets were installed in these areas following the cholera epidemic, they were quickly abandoned because of the previously described cultural factors.

The writer suspects (but has not confirmed) that the Mortlock Islands in Chuuk State may make more use of water-sealed toilets. Nama Island has fairly well developed rainwater catchment and storage systems, the writer believes, due to the influence of a number of Chuuk State Rural Sanitation Program employees who were (now deceased) from that island. It is probable that they influenced the construction of toilets as well.

In 1990, the writer spent a month on Woleai Atoll, again gathering field data to assist him in the design of appropriate water supply and sanitation facilities. The only toilet on that atoll (5 inhabited islands) was for the UNV stationed on Falalop. This trip resulted in the recommendation of the same toilet design used in Maloelap (Winter, 1991). However, the UNDP did not provide funds for construction of the facilities. That was to be a local effort. The state of affairs in Woleai had not changed in 1992 when a water supply and sanitation survey was made on 13 of the outer islands of Yap State (Seyange, 1992). Aside from the same single toilet on Woleai, only two of the islands in the survey group had toilets. One of these islands had 3 water-sealed toilets, all public; the other supposedly had 70 toilets, 45 of them being public. The writer suspects that public toilets might not be such a good idea owing to the prevailing cultural factors and to the problem of determining who will clean them. However, this opinion is unconfirmed.

The writer recently made a survey of rainwater catchment and storage systems on Pohnpei Island. Although he was not specifically looking for toilet facilities, they did not seem apparent. It may be that in the rural areas of Pohnpei the bush is the prevailing sanitary facility as well.

An often cited objection to water-sealed toilets is that they require water for flushing. This is a valid objection if water from a household’s rainwater storage tank is used. However, if groundwater (assumed to be available in unlimited quantities) or seawater is used, it is not. This approach deserves consideration by any community contemplating construction of water-sealed toilets. Unfortunately, toilets are often constructed without first resolving the issue of a source of water for flushing.

Another common objection to water-sealed toilets is that they will pollute the groundwater, especially on atoll islands. This is indeed a valid objection. The writer would strongly suspect that, for example, in the model situation of Mwoakilloa, there is a high level of background contamination of groundwater due to human waste. This situation is probably unavoidable when toilets are sited near to closely spaced homes. Typically, dug wells are in place before the introduction of toilets and, typically, they are also near the home. It is easy to see that, in a populated community, there is a very high probability that groundwater will become contaminated after a program of toilet building. Ten years ago on Chuuk, when there was still a proliferation of water-sealed toilets, the writer recalls that it was frequently difficult to find an acceptable site for a new well because toilets seemed to be everywhere.

There are a few approaches to this problem. One is to only use a well for non-consumptive purposes. Toilet flushing and washing clothes can certainly be done with slightly contaminated water. One can also bathe in it (if he keeps his mouth closed!). However, this is probably an impossible rule to enforce in the case of small children. If one has a large enough rainwater storage tank, it might be possible to use it for bathing except in extremely dry periods. The important point is that, within reason, for some uses it doesn’t matter if a well is polluted. In so far as acceptable coliform levels are concerned, a possible guideline might be to require wells used for non-consumptive purposes to have faecal coliform counts that would be acceptable for recreational waters (less than 200 col/100ml).

The problem of groundwater contamination by water-sealed toilets depends on the siting of these facilities. If one is fortunate enough to able to locate a home in a pristine area, it is easy to site wells and toilets properly. This was discussed in the first section of this report.

VIP toilets

The ventilated improved pit latrine has recently been introduced to Chuuk State. The writer is not aware of its use elsewhere in Micronesia. The reason it was introduced is that it requires no water for flushing. Thus, it eliminates the problem of water supply which was often a concern for many of the users of water-sealed toilets. It also has other interesting features.

A VIP toilet is really nothing more than a pit latrine (over-land benjo) with a vent pipe added to the waste area. The logic of the procedure is that air passing over the end of the vent pipe will induce a draft resulting in a flow of air down the toilet and out the vent. When not in use, the toilet seat should be closed. This prevents light from entering the waste area by means of the toilet. If any flies have entered the toilet, they will ultimately try to exit via the vent pipe (flies are attracted to light). If the vent pipe is screened, two of the chief objections to the pit latrine can be eliminated: flies and odour.

During the early 1990’s, over 400 of these toilets were installed on the various islands of Chuuk. In general, they have been favourably received. The writer had the opportunity to inspect (use) one of them that was in service. To his surprise, it was indeed odour-free. Sometimes, it is hard to believe that a concept really does work!

The Rural Sanitation Program in Chuuk installed these toilets. According to its former director, the toilets are apt to develop odours in low lying areas. He suspects that this occurs when the groundwater table rises to the level of the wastes in the container. It is noted that this is not a good location for a water-sealed toilet either.

Personal taste is also involved in the selection of a toilet facility. One person that the writer spoke to concerning this type of toilet indicated that some people do not like them because you can see the waste products in the container. This appears to be a matter that could be addressed in public education programs.

An important feature of this toilet is that, if toilet tissue is unavailable, any of the wide variety of alternative traditional materials (that can fit through the opening of the riser!) is acceptable. As indicated in the discussion of cultural factors, this is an important economic consideration for some families.

Although VIP toilets do not involve the addition of significant amounts of contaminated liquids to the groundwater, it would appear that they would still degrade groundwater quality. The first section of this report indicated that research is required to determine acceptable distances between water-sealed toilets and wells. The same questions apply to VIP toilets.

VIP toilets have only been in use in Micronesia for a few years. They are slightly simpler to maintain than water -sealed toilets, do not require water for flushing, and will accept any alternative to tissue that is available. For these reasons they would appear to deserve consideration for application elsewhere.

Composting toilets

A number of composting toilets have been built as demonstration projects in Micronesia (6). At least two have been built in Yap, six in Pohnpei, and one in Kosrae. Other pilot projects may be in progress. Composting toilets have a number of desirable features. Like the VIP toilet, they do not require water for operation. However, in addition, they convert the waste into a resource that can be use as a soil conditioner. Thus, they cause no pollution of groundwater.

The earliest demonstration projects began in 1992. After around two years of operation, the users were happy with the units and report that they are pretty much odour-free.

Some of composting toilet models are commercially available. Others are based on a design developed by Greenpeace (Rapaport, 1995). The intent of the Greenpeace design is that it will be applicable for use in the remote areas of Micronesia. While it does use locally available materials, the construction of it is significantly more complex than a VIP or water-sealed toilet.

The major unanswered question with respect to composting toilets is how users will react to the requirement that the decomposed wastes must be removed from them periodically and spread on the soil somewhere as a conditioner. It may take a great deal of public education to convince people to do this. The long term success of the pilot projects in Micronesia still remains to be demonstrated.


      Main Menu


  • Brochure
  • IETC Brochure

  • International Year of Forests
  • International Year of Forests

  • World Environment Day
  • ??????

  • UNEP Campaign
  • UNite to Combat Climate Change