The Peninsula, Shire-wide
About 22,000 septic systems
The Shire has records of approximately 22,000 onsite wastewater systems, many in areas served by South East Water's Peninsula Early Connection Option: Portsea, Sorrento, Blairgowrie, Rye and St Andrews Beach.
Houses, and empty ones
At the 2021 Census, 85.4% of occupied homes in the Shire were separate houses. On Census night, 27.5% of its private dwellings were unoccupied, against 11.1% across Victoria.
South East Water
South East Water's service area runs from Port Melbourne to Portsea. Mornington, Rosebud and Sorrento are on its supply list, and the Shire works with it on sewer programs.
Many small catchments
VICSES says the Shire drains through many small catchments into Port Phillip Bay, Western Port Bay or Bass Strait, and the lead time before a flood may be limited.
On septic, or on sewer?
The Shire's Onsite Wastewater Management Plan for 2024 to 2029 lists what worries it: septic systems sitting in areas that already have sewer, ageing and poorly managed systems, stormwater flooding over systems, and parts of the Shire with no sewer at all. Difficult soils, nearby waterways and small lots make some systems work less well. The Shire also backs South East Water's work encouraging owners to connect.
Not sure which you have? Ask the Shire whether an onsite system is on record for your property. A septic specialist looks after tanks and treatment systems; on sewer, a drain plumber handles your side of the line.
Storm drains near the bays
In Mornington and Mount Martha, VICSES names Tanti Creek and Fishermans Creek as the main waterways, with 4 significant floods there between 2010 and 2022. Near the water the tide matters too: Port Phillip and Western Port tides can stop stormwater drains emptying freely, and in an extreme storm water can rise back out of the pits.
A yard drain that only struggles in a storm at high tide may sort itself out. One that stays blocked in dry weather needs a blocked drains plumber.
When the house sits empty
More than a quarter of the Shire's private dwellings were empty on Census night. The Census doesn't say why, but an empty house has nobody to hear a running toilet or spot a slow leak. If you're away for weeks at a time, turn the water off at the stop tap before leaving, and if a bill jumps while nobody was home, get a leak detection plumber to trace it.
What we would do
Settle the sewer question first. Ask the Shire whether an onsite system is recorded for your address, and if you're in Portsea, Sorrento, Blairgowrie, Rye or St Andrews Beach, ask South East Water whether you can connect. Then tell us the job, whether it's a tank, a drain or hot water. A licence-checked specialist can take it, and only that plumber gets your contact details.