Excreta disposal system especially suited for emergency situations. Shallow or deep trench latrines (from 15 to 200cm) are pit latrines with trenches instead of slabs and superstructure. They can be arranged as simple trench latrines or as multiple trench latrines. In the latter case they are an improvement of an open defecation field. They should be at a distance of 15-30m from any groundwater source and the bottom of any latrine at least 1.5m above the water table. Latrines should be backfilled when full to within 0.2m from the slab.