Structural Integrity An Issue?

Make sure it’s not a swale drainage for the council. The area around the buildings needs to slope away from the building to allow for drainage as per BCA requirements below. If they plant trees, that’s additional issue.
Section 3.1.2.3 of the BCA states:
‘Surface water must be diverted away from Class 1 buildings as follows:
(a) Slab-on-ground — finished ground level adjacent to buildings:
the external finished surface surrounding the slab must be drained to move surface water away from the building and graded to give a slope of not less than (see Figure 3.1.2.2);
(i) 25 mm over the first 1 m from the building in low rainfall intensity areas for
surfaces that are reasonably impermeable (such as concrete or clay paving); or
(ii) 50 mm over the first 1 m from the building in any other case.
(b) Slab-on-ground — finished slab heights:
the height of the slab-on-ground above external finished surfaces must be not less than (see Figure 3.1.2.2);
(i) 100 mm above the finished ground level in low rainfall intensity areas or
sandy, well-drained areas; or
(ii) 50 mm above impermeable (paved or concreted areas) that slope away from
the building in accordance with (a); or
(iii) 150 mm in any other case.

Thanks to you both for your replies. I'll take it up further with the council to ensure it's all up to snuff before the wet part of the year rolls around.