I need to build a mailbox post (for two mailboxes) and have confirmed underground power and data cables exist.
Unfortunately the plans don't specify the exact position or depth and it's likely the data cables are 300mm down. I don't have access to a metal detector.
Can I get away with 200mm concrete footings? With 50mm of gravel under the concrete?
I'm thinking of making wide shallow concrete footings, with steel bolts anchoring the posts. There will be two timber posts 300mm apart connected above ground with railings (planning to make it look like our fence).
Does this sound reasonable?