Pond below a septic tank

Hi all!

I’m considering building a small pond to catch water from a roof. It would be quite small, less than 1m deep and about 3x3m. It would be a nice feature for biodiversity and as thermal mass.

The only potential trouble I see is that it would be located about 1 or 2 meters downhill from an old (still in use) septic tank.

Would this septic tank have negative impact on the pond if I’m not raising fish? What about if I was to raise fish?

I don’t have any information about the septic tank (such as leach field, etc.), except that it’s a septic tank and it’s there.

Any insight would be much appreciated. Thanks!

No problem. Unless you have plans on any certification. A meter of soil is fine for a 'normal' household. i would be more concerned about actually hitting part of the field.