Blocked Drains Boondall

1. Earthenware on the College Hill streets

   The blocks laid out through the 1950s and 1960s still carry earthenware branch lines, and decades of shrinking and swelling in the waterlogged soil have worked the sockets loose and left dips that trap paper and silt. A cracked but round pipe usually suits relining; a collapsed run gets dug.

2. Roots off the creek corridors

   Council's waterway vegetation mapping follows the creeks beside sections of Sandgate Road, Muller Road and Groth Road, and any drain joint that has opened on a backyard facing those green corridors is a moisture tap roots will find.

3. King tides at the outlets

   When a king tide lands on top of heavy rain, the Cabbage Tree Creek and Nundah Creek outlets stall, and stormwater pipes across the mapped storm-tide ground push water up through gully traps instead of carrying it away.

4. A second wave of estates

   The Gateway Motorway cut through the wetlands when it opened in 1986 and drove another round of housing, so the suburb mixes prewar weatherboard and fibro with 1980s and later brick veneer, each era with its own drainage habits.

At the last census Boondall counted 3,515 dwellings, 83 per cent of them separate houses, which is why most of the drain work here is backyard branch lines rather than shared stacks.