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3.1.1. Introduction et aperçu

QGEP consiste en une sélection d’outils et une implémentation en base de données pour travailler avec les données d’une structure de données assainissement et PGEE, abrégée en VSS-DSS.

Note

La structure des données pour les systèmes de drainage en milieu urbain de l’Association Suisse des Professionnels de l’assainissement (en allemand Verband Schweizer Abwasser- und Gewässerschutzfachleute (VSA)), habituellement abrégé en VSA-DSS, a été publiée en 1999 et représente depuis le standard valide pour les données concernant le PGEE (planning général d’évacuation des eaux) (en allemand Generelle Entwässerungsplanung (GEP)). En respectant les standards VSA_DSS, vous satisfaisez également aux exigences de la norme SIA405 assainissement, un sous-ensemble pour les réseaux d’égouts, tel que décrit dans la Norme SIA405 (brochure 2015/2016) <http://www.sia.ch/de/dienstleistungen/sia-norm/geodaten/>`_. Vous trouverez plus d’information sur la page principale du site VSA

Note

The current database implementation in PostgreSQL is for the Version 2015 of the VSA-DSS datamodel, including the extension for sewer TV inspections called VSA-KEK.

Note

We also recommend you to get a licence for the data model by purchasing the CD VSA-DSS with the datamodel in INTERLIS, object catalogues and additional description and introduction and transfer datasets in the VSA Shop

To work with QGEP-tools, it is important to know also the following norm: Wegleitung GEP-Daten which is a practitioners guide to modelling reality into GIS and hydraulic datamodel of the VSA and there specially the annex « Erfassungsgrundsätze » (data acquisition policy).

This is important because with VSA-DSS you do not only describe the manholes and channels (wastewater structures as constructive part), but with the nodes and reaches you do create the hydraulic model of the sewer network (network elements) also.

It is important to know the difference between primary and secondary wastewater facilities (pwwf / swwf). There are not the same rules for placing wastewater nodes in pwwf and swwf-networks. Catchment areas should be connected only to pwwf-network. Reaches are always created in flow-direction (flow direction in case of normal-flow).

To support the digitizing, QGEP uses two main-views: vw_qgep_wastewater_structure and vw_qgep_reach. To edit these main views, there is a special wizard and the preconfigured feature attribute windows of these views. The idea is, to support with the wizard the digitizing, so that 95% of the manholes and channels can be collected on the general-tab of the feature attribute-window, that means with as few mouse clicks as possible.

QGEP wizard

To use the wizard (Numériser les structures assainissement) is recommended for digitizing reaches because it supports snapping and connecting to the nodes preferred to the reaches. If you use the QGIS - Add line feature - tool you can not select and pick the nodes as easy.