Transport pods in sewage system

I was in a future city and the transport system comprised pods that were conveyed from one part of the city to another inside the sewage system. You got into one of a number of small pods, which were made of meatal and plastic, and it was injected into a pipe that was also filled with sewage, then it was sent at high speed to its destination. Other cities had similar systems but they were different in material respects. Some of the city systems had faults, while others were considered best practice. The city I was in had a system that was malfunctioning, and the sewage would remain coating the pods that came out of the pipe after they arrived at their destination; this was not how the things were supposed to work, I knew. The pods were very small and round and I felt unhappy about getting into one of them because of claustrophobia and because physically in my joints I am not very flexible, but I had to.

-- 25 December 2018