We're about to put a retaining wall around part of our land.
Some background.
We have 1.5 Rai of swamp close to the river, at our location the river is still tidal. Although we don't have river frontage ($$$$$) we do have tidal khlongs on 3 sides, 4th side is the road.
I want to put in a retaining wall round part of the perimiter the idea being to keep our expensive fill from disappearing with the tide.
The khlongs are 2-3m wide and of uncertain depth. The neighbours have similar walls down their side, one has a house wall close to the edge.
Our contractor wants to use driven concrete 'H' piles with an angled brace on the dry side, the gaps being filled with 2m concrete planks, we then fill in behind to level and gain a couple of metres of flat, useable garden.
I'm worried about driving piles this close to the neighbours although doubtless the water will absorb much of the energy.
Anyone got experience? What happens if next doors' wall collapses because of our contractors' activities? Our problem, their problem, contractors' problem?