Pete C wrote:

I'm planning to dig a fairly shallow trench for some MDPE pipe, and
would like to hear any tips on how to go about it, or how long it
should take to dig 40m of trench.

It's not going to be that deep as it's in a well sheltered low lying
area, I was thinking of cutting down a cheap spade to dig a narrower
trench, or would this make it trickier to get the earth out?

If this is for water supplied by a utility company, then there are
restrictions on the depth - I believe most companies specify a 600mm
minimum depth.

If it's for a private supply, I wouldn't want to bury it less than 450mm
deep anyway. Not so much because of issues with freezing, but because of
risk of damage.

I don't know how shallow you intend to bury it, but I'd want to use a
digger for this. Even a 400mm trench 40m long would take a couple of
days to dig by hand, and that's in reasonable soil. If it's particularly
rocky then that could easily double.

--
Grunff