Mark Brader wrote:
snip
Incidentally, a new air-conditioning system http://www.enwave.com
is now coming into use for major downtown buildings here in Toronto,
taking advantage of our location on Lake Ontario. Heat from these
buildings is transferred into water being drawn from the lake for
the city's drinking water system; the drinking water won't get
significantly warmer than it now does in summer, because the water
used for this purpose is coming from a new feed deeper in the lake
where the temp- erature is always 4 Celsius (at which water is
densest). Unfortunately, London doesn't have a Great Lake next to
it...

Yes, it does! According to LU's Environmental Report for 2003, they
pump over 30 million litres of water out of the tunnels every day. The
water originates either from the rising water table under London or from
leaking water mains.
--
Richard J.
(to e-mail me, swap uk and yon in address)