I am in a weird spot. Short story. Church was flooded again. We enclosed our pavilion to meet there till construction is over. Had a thetford upflush system donated. Pump doesn’t work. But can these toilets be used as standard European style rear flush ? My drain is right out side. We elected to use this system to keep from adding to concrete or cutting the existing. Building is temporary and will be removed. If I can use this toilet without pump. That would be awesome. Anyone tried this ?