Reading the recent thread about treatment palnts has made me wonder if we are overcomplicating things.   We have all sweated blood to reduce our heating bills by perhaps £1000 per year, and cut the concomitant environental impact. Good.   But spending £400 or £600 a year to run a treatment plant seems to me to be a backward step, as it is as much as, or more than, mains connection (South West excepted!).   As a household we are now on mains drainage, but at our old