The sewer installation boundary is a manhole boundary, specifically a standard manhole (Abwasser Normschacht) that's astructural element. It can also represent the manhole's area, derived from attributes such as diameter and shape.

Sewer structure boundary manually recorded as a structural element representing the area of a sewage structure.

The structure is a discharge structure boundary, specifically the structure of an outflow inlet. This is where a sewer system discharges into a body of water (flowing or standing). Not all discharges require a structure;those without are recorded as "StormWaterDeliveryPoint". If a structure protects the discharge point, it's recorded as a DischargeStructureBoundary.

The item is a boundary representing the area of a sewage treatment plant, encompassing all its basins and buildings.

Infiltration structure boundary: This is the surface area where clean wastewater and slightly contaminated rainwater infiltrate the ground (as defined in the VSA guideline for rainwater disposal 2002). It's the structural extent behind the infiltration delivery point (e.g., a seepage shaft) that supports or protects the inflow into a retention body. The structure may be associated with a retention body(retention zone).

The sewer installation boundary's feed boundary (code 807) represents the extent of the feed point. This encompasses areas such as wells, specific buildings, or zones connected to the sewer network.

Sewer duct boundary: An open or closed channel for draining wastewater between two wastewater structures. From a structural perspective, it represents wastewater pipes. The area object is optional for the sewer duct(StructureEdgeObject "SewerDuct"). If the extent of the sewer duct is not satisfactorily represented by the line thickness (GravityLine, PressureLine) in map symbolization, this area can be used to show the specific extent of the duct.