For practical purposes, it is not only important to assess and document the condition of sewers, the position of the pipes in the ground is also of interest. Pipe run surveying and hydrostatic level measurement are instruments that contribute decisively to ensuring high quality inspection of sewers on private property.
Both procedures help the inspector to supplement the data on the sewer network and enable layout plans of complex lateral sewer networks to be drawn up. With the plan, besides the actual inspection results (documentation of defects etc.), you get a map of the pipe run with only a minimum of addi¬tional time and effort, as the survey is performed at the same time as the inspection. Pipe run surveying with 3D-GeoSense supplies the xyz coordinates of the laterals and thus provides a 3D plan that helps to find the locations of any required rehabilitation measures or other construction work (e.g. addition of further laterals). A hydrostatic level measurement allowing the level (z coordinate) to be determined even more precisely (accurately to a centimetre) can be per-formed to supplement the 3D-GeoSense pipe run survey. In addition to the pipe run survey in laterals, the run of mainline sewers can also be surveyed.
With the IBAK LISY 3 system for lateral inspection (satellite system and calibrated ORION with Kiel Rod guide unit and POLARIS as the case may be), the inspection and the pipe run survey are performed in one single operation.
The system permits the inspection of laterals from DN 100 upwards from mainline sewers. The system is driven by flushing or, as is now the case with the new LISY generation, also without flushing, simply by using the push rod of the LISY system. With the flushing alternative, the pump, the hose and the nozzle are opti¬mally suited to each other so that, together with the very light camera, it is possible to flush the system a long way without using very much water.
A great number of IBAK cameras are nowadays suited for the pipe run survey. There are the lateral cameras ORION 2.9, ORION 2.8L, NANO, NANO L and POLARIS as well as for example the main sewer camera ORPHEUS 2/3 as 3D versions. Using the additional required equipment (e.g. software, DEIMOS/PHOBOS) they measure the pipe run.
The IBAK pipe run survey system uses a very small, precisely precalibrated sensor.
It is particularly small and space-saving and is calibrated ingeniously before use.
This calibration and a compensation pro¬cedure to eliminate clear systematic sensor errors contribute to ensuring a most precise display of the run of the lateral network. The gradual generation of the lateral network can be observed in real time on the monitor. The operator can choose whether the survey is to be performed while the camera is moving forwards or in reverse. To survey the pipe run in mainline sewers, all that is required is a conven¬tional IBAK system equipped with the corresponding IBAK software and a camera with a precalibrated sensor. During the inspection of the collector, the xyz coordinates can be determined in this way without any additional effort and the actual pipe run can be displayed in the plan. The 3D-GeoSense survey, i.e. determining the xyz coordinates, is suppor¬ted by the procedure for hydrostatic level measurement in complex sewer networks that has recently been developed by IBAK. It is used to determine the differences in level or the invert elevation in mainline and lateral sewers. With this method, the elevation of pipe networks (z axis) is measured accurately to a centimetre. So supplementing 3D-GeoSense with hydrostatic level measurement is always recommendable when the elevation of the pipe run is a decisive part of the inspection results.
To enable the data collected with the camera to be further processed properly, the hardware is supported by special software tools. With IKAS evolution, data measured by the 3D sensor (xyz coordinates) can be collected fully automatically. This is done together with the TV ins-pection in a single operation. IKAS evolution also permits the real-time display of the surveyed pipe run as a network graphic* during the TV inspection. Map material (e.g. the layout of a building) can be read into the software and adapted to the correct size so that the resulting lateral run appears directly in the plan. The pipe run is saved unambiguously in terms of geography with three-dimensional coordinates (geo-referenced), so that you can always see at which position on the Earth the pipe run is located. The resulting layout plan can be exported easily to all supported sewer data formats**. It can be adapted to precise position coordinates, generally known as geo-fix points, with the assistant functions of the software*. IKAS evolution also supports the collection of the level measurement data which are determined semi-automatically by the level measurement system. The collection of this data is also performed in a single opera¬tion together with the TV inspection just like the pipe run survey with 3D-GeoSense. The level fixed points are analysed and adapted with the assistant function* in IKAS evolution.
* The IKAS evolution MAP Route Assistant is required!
** Depending on which IKAS evolution sewer interface is used
For further information on IKAS evolution refer to “IKAS evolution”