Ground, water and flooding in Riverstone NSW

Riverstone flooded in 2021, with homes along Marsden Road inundated. That is a planning and conveyancing matter for any particular lot, and the flood mapping is the place to settle it. What belongs on a building inspection is narrower and closer to the house: whether the ground falls away from the slab, whether stormwater actually leaves the property, whether pits hold water, and whether condensate is discharged where it should be. We recorded water ponding in a silt pit and an air conditioner draining onto the ground at handover on Riverstone jobs.

Guides for Riverstone owners and buyers

29 January 2026 · 8 min read

Three weep holes, three different failures

Missing, too high, and off the flashing.

23 February 2026 · 6 min read

Damp proof course, and why it is a lock-up item

Rising moisture is stopped by a layer nobody sees again.

19 August 2026 · 6 min read

Insufficient ventilation, and what it costs later

Air movement is a structural question, not a comfort one.

Ground, water and flooding in Riverstone NSW: common questions

Do you assess flood risk?

No. That is council flood mapping and a conveyancer's search. We assess how the building handles water on and around the site, which is a different and much smaller question.

Why does condensate on the ground matter?

It puts a continuous trickle of water beside the slab, right where you want the ground dry. It should be plumbed to a legal discharge point.

What about the soil itself?

There is no valid suburb wide site classification. The class is determined lot by lot from that property's soil report, and the slab is engineered from it, which is why we check the slab against your engineering rather than against an assumption.