Janet Baraclough wrote:

Hello Janet

S I need to get a bridge to span an 18ft dyke.
S It doesn't have to be too ornamental, functional is
S fine. Does anyone have a favoured supplier.
I don't think there's a "Bridges R Us" type chain. Your
best bet is to open the yellow pages and find a local
engineering works who'll be able to knock up something to
suit your needs. You'll probably also need a builder on
site to erect/install it, but that's something you can
sort out with your engineer.

JB Probably the cheapest way to do it, it with 2 ex-telephone
JB poles as the spans, fixed to vertical stobs driven into the
JB banks, and planks nailed across the poles as the surface.
JB Farmers often have a stash of the poles.

Possibly, it's a shame the OP didn't give more details. I can't think
of many private gardens with 18' dykes in them, so it could be a
public garden or place where the public has access, in which case a
home-made bridge might not be good enough. (From the insurance POV,
certainly)

Plus, the thing about telegraph poles is that they're usually removed
because they've failed a safety inspection ('D' classified) which
means they're unsafe to be climbed. I wouldn't personally trust them
on such a long unsupported span for more than 1 or 2 people (think how
many people you can get on a bridge!) for more than 5 years or so.

--
Simon Avery, Dartmoor, UK Ý http://www.digdilem.org/