Manholes. Yes, manholes. And I'm not being tacitly gay here; I'm talking about the ornate manhole covers that can be found all over Japanese streets. Every city, as far as I can tell, has its own design. To see more, please visit my gallery Put a Lid on It.
Waste water, outside of Shin Yamaguchi station in Yamaguchi prefecture.
Another manhole for waste water in Shin Yamaguchi.
I'm not exactly sure what the difference between "waste water" (汚水, osui) and "sewage" (下水, gesui) is. A cursory search of the Internet suggests to me that osui is actually what we would consider "sewage", that is the water and excrement from homes while gesui pipes carries run-off from rain. (Don't trust me on this, though.)
Taken in Shin Yamaguchi. Not sure what it is, but has the look of . . . no, I won't venture a guess just yet.
Gessuidô, sewage pipe in Tsuwano, Shimane prefecture.
Osui, waste water, in Tsuwano, Shimane prefecture.
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