[Default] On Sat, 15 Oct 2011 09:14:30 +0100, a certain chimpanzee, MM
, randomly hit the keyboard and wrote:

Or can builders opt to install individual septic tanks/cesspits?

These are small housing estates of up to, say, 50 houses not on mains
drainage.

Whichever works. If the area of land available to the individual
houses is large enough, they could have their own, otherwise a
communal system is required. I suspect it's the developer who would
prefer a single larger system than 50 individual systems.
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