Plumber in Thirroul

Thirroul floods fast, and Council has said where. The suburb sits in the Hewitts Creek catchment, roughly eight square kilometres shared with Bulli. Wollongong City Council's own catchment page names three problem areas in Thirroul: Lachlan Street, where culvert blockages cause property inundation; The Esplanade, where shallow flooding affects the recreation zone; and the Corbett Avenue / Hamilton Road area, where mitigation works were assessed and "deemed economically unfeasible". If you are in that last group, Council has effectively told you the fix has to happen on your own property.

April 2022 is the event people here still talk about. On 7 April, Lachlan Street was described by the Illawarra Mercury as "a raging torrent thanks to a swollen Hewitts Creek", and it was the second time it had flooded in a fortnight. The same day a backyard at Kennedy's Hill partially slipped down the cliff face to the ocean. That is the pattern we plan for on Thirroul properties: not a slow river rise but a wall of escarpment water arriving within minutes of heavy rain. The NSW SES says the same thing about the whole Wollongong LGA, that flooding here "is dominated by flash flooding" with streams responding quickly to high-intensity rainfall.

Escarpment runoff is a plumbing problem before it is a council problem. Thirroul has about 400 metres of near-vertical catchment sitting directly behind it, so anything that funnels water at your boundary will be tested hard. Practically, that means sizing downpipes and stormwater lines for the real load rather than the minimum, keeping charged lines and pits clear, checking that surcharge gullies are at the correct height, and putting in overland flow paths and sub-floor drainage on the uphill side. Blocked conduits are so central to Thirroul's flooding that Council's 2019 flood study revision was rewritten specifically to incorporate its Conduit Blockage Policy.

The slope itself is documented. The University of Wollongong maintains a landslide inventory of almost 600 sites and around a thousand recorded events across the region, and Site 113 at Thirroul has sixteen documented recurrences since it first moved in March to April 1950, still active 54 years later in October 2004. On escarpment land, Wollongong DCP 2009 Chapter E12 requires geotechnical assessment by a qualified consultant. That matters for plumbing because trenching, soakwells and any concentration of water on a slope can all be geotechnical questions, not just drainage ones. We will tell you when a job needs a geotech before it needs a plumber.

The housing stock is layered, and each layer fails differently. Land subdivision here accelerated after 1906 with the McCawley Park Estate auctions, and the Excelsior No. 1 and No. 2 collieries ran from 1900 and 1902 through to 1962, so Thirroul has a genuine stock of pre-WWI and interwar miners' cottages, then post-war infill, then two decades of premium renovation. Behind a Thirroul wall we find galvanised steel, early copper, vitrified clay sewer with root intrusion, and sometimes all three spliced together by a previous owner. We CCTV before quoting anything structural rather than guessing from the age of the front door.

Thirroul is properly beachfront, so salt is in play as well. Copper pipework, hot water unit casings, outdoor taps, roof flashings and gutter fixings degrade faster within a few hundred metres of the surf. If you have a stainless or copper hot water unit sitting on the seaward side of the house, it will not last as long as the same unit at Figtree. Annual maintenance genuinely pays for itself here.