Channel drainage

Hi all, first post here! Looking for some advice please. Perhaps someone’s been in a similar situation.

I need to install a run off channel drainage (roughly 100m) in front of the grain stores to try to stop flood water from getting in.

Can anyone tell me which kind of channel drainage I will need? I read a guide that says I will need D400 so I’ve searched the internet and came across products such as these but they’re so expensive! It works out at around £6000 for the amount I’ll need.

Is this the only drainage that’ll do the job? There will off course be machinery running over it. Can anyone else recommend a more cost effective solution?