On 15/10/2011 09:29, MM wrote:
Where I live the sewage treatment plant recently broke down and needed
a new pump. Householders each had to pay a relatively small sum of
money in order to avoid tapping into the contingency fund which is
really there for replacing the entire plant in 20 years' time.

And then a number of residents refused to pay, for whatever reason I
don't know. Those who had paid got their money back and the bill for
the new pump plus labour etc was paid from the contingency fund
instead.
....
A new plant for 40 houses would cost around £35k at today's prices.In
20 years from now it could be double or treble that, so building up
the contingency fund is vital.

Does rhis imply the householders don't pay a sewage charge to the water
companies?

I'd not treat the money as a contingency fund for a new plant. There
should be an annual charge, payable by all (possibly based on ratable
value), which will cover all costs related to the sewage system. This
includes maintenance costs and capital costs, ie building up reserves if
necessary. You'd need something to administer this - whether it's an
existing company or a new one. They'd need to be able to take out loans
to pay for significant capital expenditure if their reserves were
insufficient, or to insure for the same costs.

When people balk at setting up such a thing, work out how much they'd
pay for the sewage charge to a water company.

Or of course get a utility to take on the whole thing for a one-off cost.