Waste doesn't exist in nature.

Toilet

Our van came with a cassette toilet, which is a tank similar to a conventional household toilet, but it requires chemical additives (formaldehyde or quaternary ammonium compounds) to control odour and break down solids. These additives suppress bacteria but also prevent natural decomposition and require disposal at designated facilities.

A safer and more sustainable option would be a composting toilet, but since the van already had a fully functioning unit, I chose to repurpose it into a dry system rather than replace it.

Repurposing a cassette toilet as a urine-diverting dry toilet

When liquids and solids are kept separate, they are both manageable and even useful.

Liquids

The original tank is now used only for urine. It is odourless if diluted and emptied regularly. Urine is composed primarily of water, with nitrogen, phosphorus and potassium, which are nutrients for plants, so it can be diluted with water (about 1:10) and used as a fertiliser. When this is not possible, we can still dispose of it at any appropriate facility without worrying about chemical contamination.

Solids

Solids are managed separately. Before each use, the toilet is lined with a compostable bag and filled with sawdust. This keeps everything dry and odour-free during the initial composting stage. After use, we tie the bag and store it until it can be transferred to a dedicated composting system or disposed of at a public pet waste station. We don't use it directly as compost right away because it takes time for the material to become safe for soil.

What's left over

We try to minimise waste, but sometimes we still have organic and dry materials to manage.

Food scraps are stored with sawdust to prevent odours and pests until they can be added to a composting system or placed in a public compost bin. We follow a vegetarian diet so our scraps decompose more easily. For omnivores, some items may require different treatment.

Dry materials that cannot be reused or recycled are separated and stored until we find a suitable recycling centre or public bin to dispose of them.