William here with a bit of news about water supply infrastructure. Damage initially caused by the Thursday quake was exacerbated by the Saturday quake. As an example, the Ryujin Bridge over Shirakawa, which primarily functions as a water conduit to feed the Toroku and Oe areas, completely collapsed, taking the conduit with it. (April 22 update from Kirk: The collapse of Ryujin Bridge was reported at the time but proved not to be true. I visited the bridge today and, not only was it still standing, cars were passing over it as usual.)
Detailed info is difficult to come by; likely, even the pros do not know. However, my uncle who works in construction said water should return to some areas from Monday. The return will be sporadic, with some areas receiving water before others. Also, those living in condominiums may face further delays due to building infrastructure damage, particularly roof-top tanks.
Finally, Kumamoto City has called again for water conservation. The majority of bottled water stored by the city has already been distributed, though supplies from the national government are expected. Of particular worry is the health of those hospitalized and the sanitation of those facilities.
