I read on this some time ago; it's hard to find more recent information on if it's gotten any better. The investors for these big buildings wanted to get in quick during the rush so they just built before the city was able to provide the proper infrastructure for such large requirements.
Toilet and drains works like normal for people living there, why should should most people take notice in buildings? They wouldn't think of it as third-world. Although, with the long waits, apparently illegal dumping into rainwater drains did become quite common, which, in turn, drains into the ocean. That's quite gross, especially for an area that is being promoted as a tourist area.
Here's the location on maps:
Yahoo Maps seems to have the most up to date imagery. They've actually built an allotment to the east of the sewage plant for trucks to wait before they go in. On
Google Maps the line is much shorter, maybe it was taken early morning, or more recently if the situation has gotten better.
Bing Maps doesn't even have the lot to the east on their map yet, but you can see the long lines of trucks going for about a mile to both the west and east.