The Aquaducts of Edo

In Edo people found that digging deep wells was not that practical because the ground was soft, sandy and somewhat salty - which makes sense the proximity to the Pacific.  What they decided to do in the suburbs of Edo was lay the wooden aquaduct pipes about 1m underground and link them with large wooden wells.  The wood was kept pest free because of the salty soil and were also, therefore pretty long lasting.  The aquaducts were fed from reservoirs in the mountains.

The commoners had a community well rather than water to their house - and this was also close to the community toilet and bath.

Commoners were forbidden to have fires in their houses because of the risk of burning the enitre city to the ground (which happened many times bankrupting the daimyo had had to sustain a residence in Edo and back home) and the city was even alid out with very very wide streets to form as fire-breaks.  The bath was a place for locals to meet and have legal fire - and that history is the reason that in many Japanese cities today you still find community bath houses in the inner, older suburbs.