What's specific to Marion
30.7% townhouses and semis
At the 2021 Census, 67.7% of the suburb's occupied homes were separate houses, 30.7% semis, terraces or townhouses and 1.2% flats.
A quarter rented
24.8% of homes were rented, close to the state's 27.6%, with 33.9% owned outright and 29.8% under a mortgage.
Groundwater prohibition
The EPA lists 'Tonsley and parts of Clovelly Park, Mitchell Park and Marion' among its Groundwater Prohibition Areas, where bore water must not be used.
Infill on Council's mind
Marion's stormwater plan lists urban infill, more housing and more hard surfaces as future demands on its drains.
Infill and townhouse drainage
When one house block becomes two or three dwellings, roofs and paving replace garden, and more water heads for the drains at once. City of Marion lists infill among the future demands on its network, and says project work to lift drainage capacity is on target.
For owners, the practical issues are shared pipes and tight access. In a townhouse group, a blocked line may serve several homes, so check your title or community plan before anyone digs. A CCTV drain inspection shows where one home's pipe joins another's.
Bores in the prohibition area
The EPA sets up a prohibition area to protect current and future landholders from contaminated groundwater. Mains water and rainwater aren't affected, and buyers are told through the Form 1 statement. If a Marion property has an old bore, don't hook it up to irrigation or a tap until you've checked the EPA's prohibition area details.
Trees and trenches
City of Marion's July 2026 fact sheet explains the state tree rules. A tree is regulated once its single trunk measures 1 metre or more around, 1 metre above the ground, and significant at 2 metres. Any tree-damaging activity needs approval, and that includes earthworks in a tree's Structural Root Zone or Tree Protection Zone.
So a new sewer or stormwater trench near a large tree is a conversation with Council first. Relining, which repairs the pipe from inside, can avoid the dig: see pipe relining in Adelaide.
Other help nearby
Job pages: blocked drains, leak detection, hot water repairs and gas plumbing. Also in the City of Marion: Hallett Cove.
What we would do
On a townhouse or infill block, find out who shares your drain before the first quote: the answer changes who pays. If the job means digging, measure any big tree's trunk 1 metre up and ring Council if it's close to 1 metre. And leave old bores alone until you've checked the prohibition area. Then we'll match you with a drain specialist who works on tight sites.