songbird wrote:
some of them can be problems, in general if you are
going to use household waste water for the gardens it
is a good idea to switch to products which can be
biodegraded (often via what is called a reed bed) in
some manner before it gets to the gardens. some things
are toxic above small amounts so should not be used.
Are there detergents that really work and don't louse up
the water? Borax is obviously out of the question, bleaches
will have to be h2o2 based, but I think they're available.
the idea was that the soil should filter and clean the
remaining water coming from it, but they are discovering
that the soil does not clean it as much as expected so
effluent plumes are getting into the rivers and lakes.
Nutrients, or pathogens?
in the end mixing human waste with water makes the
problem much worse than needed because then the human
waste has to be taken back out of the water anyways.
why not just keep it from the water to begin with? so
until people realize that the initial design is horribly
flawed we'll be stuck with this rotten and pollution
encouraging mess instead of doing things in a much
smarter way.
Composting toilets are a good option in low-density
environments, but would they work in higher density places,
say 10ksf lots, 3bd/2ba houses? What about apartments?
with cheap energy much becomes possible, but if you
design a smarter system that doesn't pollute water to
begin with you can avoid a lot of problems (and expenses).
Most of the developed world uses single-stream sewage collection
and already makes at least a token effort to clean up the wastewater.
With a little more effort and energy the water could be cleaned up
enough to go back in the supply. From what I gather, solar energy
in Germany has fallen to zero cost for portions of the day. The
same is apt to happen here if wind and solar investments continue.
Reverse osmosis plants can stop and start relatively quickly, that
seems like a good use for the excess energy.
Here's a link that some might find interesting on the subject of
reverse osmosis and its efficiency:
http://urila.tripod.com/Seawater.htm
The article focuses on seawater desalination but the discussion
makes it very clear that domestic wastewater is much more efficient
to recover, especially if the degree of desalination is modest.
Hope this is of interest,
bob prohaska