Wahroonga in brief
Ku-ring-gai and Hornsby
Ku-ring-gai Council's Wahroonga ward and Hornsby Shire's Ward B both name the suburb. ABS figures put 73.2% of its dwellings in Ku-ring-gai and 26.8% in Hornsby Shire.
Large share of houses
At the 2021 Census, 74.5% of occupied homes were separate houses and 19.6% apartments. 38.4% were owned outright, and 17.8% rented against 32.6% for NSW.
Three conservation areas
Ku-ring-gai lists the Mahratta, Wahroonga, and Heydon Avenue Warrawee Woodville Avenue Wahroonga conservation areas. Tree work there, or on a heritage item, needs a Council application.
Easements are private
On the Ku-ring-gai side, private inter-allotment drainage easements are maintained by the properties that benefit from them, not by Council.
When the shared drain blocks
An inter-allotment easement is a private drain that crosses lower lots so higher ones can drain. When it chokes with silt or roots, the water backs up into the yards upstream. Ku-ring-gai Council treats the line as the responsibility of the lots it serves, so the neighbours along it need to agree on the repair.
The same idea applies to sewer pipes. Sydney Water says every owner who shares a joint private service is responsible for it. One drainage plumber clearing and inspecting the whole run, with the cost split between the owners, is usually simpler than each house hiring its own.
Ku-ring-gai officers may also take no action where water is natural run-off from properties above, or where an approved drainage system simply overflows beyond its design capacity in a big storm. Your own pipes, from the house, garage and other structures to the kerb and gutter, are yours to keep working.
On the Hornsby side
About a quarter of Wahroonga's dwellings are in Hornsby Shire, and the Ku-ring-gai rules on this page don't cover them. Your rates notice tells you which council you're with. Ask that council about its own easement, tree and heritage rules before work starts.
Sydney Water's share
Sydney Water owns its main and the junction on it. From the house up to and including the point of connection, the wastewater pipes are the owner's, wherever the boundary falls. If it collapses under a footpath or road, Sydney Water may repair it for residential customers, once a licensed plumber confirms digging up the footpath or road is the only way. For the water supply, see leak detection in Sydney.
What we would do
If your yard floods during rain, find out whether your block drains through a shared easement before you call anyone. If it does, talk to the neighbours on the same line first, then have one drainage plumber camera-inspect the whole run so everyone sees the same evidence and the cost can be split fairly.