As sewer and stormwater are gravity systems, the site must fall towards an existing or proposed sewer and stormwater connection for a subdivision to be possible. A ‘Dial Before You Dig’ search is not sufficient alone to determine if a site can be serviced as it doesn’t show the depth of relevant mains. If they are not deep enough to service the site, alternate mains may be required. There can also be capacity issues that could prohibit a subdivision in an area with costly upgrades required potentially at the developers’ expense.
Any land falling away from a street (rear falling) will usually have a sewer either passing along its lowest point or through the neighbouring property. Where a main sits in a neighbouring allotment, there will likely be a single sewerage connection provided to the site. A single connection can’t be used to service more than one allotment, and all lots must be provided with an independent sewer connection directly from a sewer main.
Where an existing main is located in a neighbour’s property, the property owner’s written consent is required to gain access to their land and undertake works to augment the sewer network and provide sewer connections to the new lot/s. Likewise, stormwater is nearly always required to drain through a pipe to a lawful point of discharge, and quite often, this may be to a street at the rear of a site passing through a neighbour’s property. As with the sewer, written consent from the neighbour is required to construct a stormwater pipe through their property, and in some cases, provide easements to council over the sewer or stormwater mains.
If agreement is required to undertake works in a neighbour’s property, but the neighbour has not consented, in many cases council will not approve a subdivision over the site. However, some council’s do not assess water and sewer services where there is a separate water corporation and can approve a subdivision application without assurance these services can be provided. There is a risk that in these circumstances council will approve a subdivision that cannot be acted upon if sewer and water cannot be connected if any consent from neighbours hasn’t been provided.
Each council has different policies on stormwater management, but the requirement to connect to the reticulated sewer system is usually always the same. For larger subdivisions, some may allow a private sewerage pump station to enable sewerage to be pumped uphill to the nearest reticulated sewer main, however this approach is inconsistent between different jurisdictions.