In article , John Towill
writes
I've asked this question on uk.diy as well, as I'm not certain of the best
venue. My septic tank soakaway runs diagonally across my garden, will it
adversely affect its function if I plant trees/shrubs near or over?
I suspect that the roots, seeking out water, will penetrate it, but bearing
in mind that they will utilise a lot of the water would it do any harm?

The only problem I see with planting anything 'big' over your soakaway
is that the roots will 'seek' the moisture and damage it (
A birch tree had practically blocked one of our septic tank pipes with
masses of fibrous roots (

--
Jane Ransom in Lancaster.
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