The problem I see with any kind of composting solution is that as far as I understood there is no substantial agricultural activities on these islands, and thus little motivation to acquire good organic fertilizer.
A bucket toilet might work just fine, however I really wouldn't be surprised if after a short time people just start dumping the contents into the backyard/ocean again.

Therefore my idea to implement an artificial reef for fish breeding. In north Vietnam I have seen a quite interesting way of making artifial fish breeding areas under the floating villages of Halong Bay. Basically they hang a lot of sand filled buckets under their floating rafts, and due to the high nutrient (the water is completely green from algae), shallow and calm waters of that area, it becomes a perfect breeding ground.

Well... sure this is probably not the perfect reuse of human remains, but one of the few where I actually see some benefit for the communities, and as the fish are (usually) not consumed directly/immediately, the negative health impact is probably relatively low.

Hi Christian,
I just visited Duramawang Elementary School, in the Philippines, which is a flooded area and I think you visited there as well...(i am not sure if you are the same Christian who visited there).

When I saw the area, i came to realize that UDDT is never a best or better option due to the difficulty of procuring resources within the area for maintaining and operating the UDDT...besides it's difficult to transport materials(e.g. sawdust, charcoal, etc) needed for daily operation for UDDT.
On the other hand, toilets with simple or conventional septic tanks is never an option as well since it is really a flooded area...
My opinion as better sanitation facility option for flooded area would be:
1.constructing a pour flush toilet
2. have a water proof septic tank
Treatment option: once the water proof septic tank is full, it will be locally desludge and placed in the pit which is lined with a thick plastic lining or tarpaulin to avoid groundwater or sea contamination. Once the sludge is already in the pit, it will then be treated through raising pH to 14 .

HI Christian,
Thank you for this option..

Terra Preta is wonderful, but i am still into pour flush with a water proof septic tank since charcoal is very much limited in island areas...


Thanks..

Analiza

Dear Analiza and Julius,
Thank you for this valuable input. I agree with you that UDDTs, Terra Preta and similar dry sanitation technologies are not suitable for this flood-prone area. That is why we have so far settle on pour flush toilets with a water-tight septic tank. However the discharge of effluent from the septic tanks is yet unclear. I thought to infiltrate it into the ground which would automatically happen during low tide, however I am not sure if the ground has the capacity to soak water. There was also an option mentioned in this discussion with a floating pipe to the sea, but that seem technically not easily feasible.

The suggestion from Julius on the aquaculture option seems very promising to me. We could use the pre-treated effluent from the septic tank and use it in a fish pond or artificial reef. In Darumawang they told me (I was there myself) and the other colleagues that they once had something like a fish pond, but somehow this project has failed. Not sure why, but a reasonable option to follow up.

@Julius, could you share pictures from the artifial fish breeding areas under the floating villages of Halong Bay in Vietnam?

I am attaching a sketch of the proposed toilet setup for the school. Please feel free to comment on it.

Best,
Christian

christian.rieck wrote: @Julius, could you share pictures from the artifial fish breeding areas under the floating villages of Halong Bay in Vietnam?

Here you go:


Edit: I *think* they are used for fish breeding, but maybe someone knows better? Might be for mussels?