Special structures (weirs, retention,..) and export to SWMM

[TriformMoritz]

It is crucial to easily to digitize and describe hydraulically special structure and export them for modeling, for this these points should be supported:

• Description of the hydraulic structure like in appendix 3 of the VSA-wiki (https://vsa.ch/fr/wiki/ ), "Guide des données de l’assainissement urbain", chapter 2.3
• Documentation of how to enter each of these special structures in TEKSI wastewater
• Automatic export to SWMM of these special structures.

[sjib]

• [x] Automatic export to SWMM of these special structures - is supporte in 13_vw_swmm_storages.sql and 02_vw_swmm_junctions.sql

@TriformMoritz Do you need any others? -- 5372 -- "stormwater_overflow"?

[TriformMoritz]

I am not able to model anything different than a very simple weir inside QGEP yet. For example (BEP): https://vsa.ch/fr/wiki/3-2-13-bassin-deaux-pluviales-bassin-de-decantation-en-connexion-laterale/

I am not able to tell to tell how to model this (I tried) in QGEP

• I cannot connect two or more "main" nodes.
• If I connect a main node, I am not able to make a detailed geometry (and I don't know to which node).
• Two or more weirs are difficult.
• The way documented by Urs works (for one weir) but is very difficult and not at all intuitive.

Please try yourself, I gave up after two hours.

The export to SWMM comes afterward. Concerning the SWMM export:

• Curves are supported in VSA-DSS (HQ-Relations), so they should also be imported into SWMM-> Weir curves, I don't think tidal curves are yet supported in VSA-DSS.
• Flow_valves (Limitateur_debit) are supported in VSA-DSS, so they should also be imported into SWMM-> Control curves.
• I am not sure if storage curves are supported in VSA-DSS.

[urskaufmann]

I have documented, how to construct the VSA-example 3.2.13 There is one real problem with the obj_id, that are automatic set as last_value+"-1" and therefor are too long (see also Issue #619 ) VSA Example 3-2-13 in QGEP.docx

There should be a new vw_overflow_line. And the network following should work also with this overflows.

[TriformMoritz]

My first problem: I cannot digitize, the error say : "Ajouter partie" at the end of my digitizing try:

[sjib]

I tried with two different projects I have - with the first one I get the same error as @TriformMoritz - with the other digitizing a detailed_geometry works fine. It is on the same database. The first node is within the network. The one that works is at the end (Vorflutereinlauf). When I try in that project file on a node within the network it also fails. So it looks not like a problem of the project file version. In German the message is 2022-03-07T16:59:52 WARNING Teil hinzufügen Tested with QGIS 3.16.14

[sjib]

Found some information here: https://github.com/qgis/QGIS/issues/41294 that has been fixed in 3.20 (https://github.com/qgis/QGIS/pull/41391). @TriformMoritz Can you check with the latest LTR 3.24 if this still happens?

[sjib]

And this hint in the documentation: If the geometry disappears after digitizing or if you get an message (like ‘Add part’), you have probably tried to digitize over a catchment area (or an other polygon theme) and the layer has set the avoid overlap option in the snapping settings. Do change the avoid overlap settings.

Very bottom of https://qgep.github.io/docs/user-guide/digitizing/digitizingdetailedgeometry.html

And here a screenshot of Snapping settings: In 3.24 it now gets more information - maybe you find out why it is invalid.

[TriformMoritz]

Works, thank you! The error message (of QGIS) should be clearer, like -> "Overlapping not allowed in snapping options" or "les options d'accrochage empèchent la création de la géométrie"

[urskaufmann]

Add part-error: Stefan showed the solution. See also Issue #628

[TriformMoritz]

So it worked (I actually had all the weirs defined already, but they weren't visible and not exported to SWMM so I could not check), thank you Urs for the view!:

I would propose:

1. Make the view editable -> Possibility to draw a weir line (and fill out the attributes), either in the wizard or in the edition of the view (like the line catchment to node). -> New feature in QGEP
2. Correct the OID error documented by urs (https://github.com/QGEP/QGEP/issues/619 )
3. Export to SWMM of weirs, storage units and dividers. -> New feature in SWMM

[tproduit]

• Flow_valves (Limitateur_debit) are supported in VSA-DSS, so they should also be imported into SWMM-> Control curves.

@sjib Is their a corresponding table in QGEP datamodel? I'm not able to figure out which one.

[tproduit]

• I am not sure if storage curves are supported in VSA-DSS.

@sjib Are they supported? Do they exist in QGEP?

[sjib]

Hydraulic classes in VSA-DSS

hq_relation and overflow_char (Ueberlaufchrakteristik) have the parameters needed for the SWMM curves (see chapter C.5 and 3.28. of the SWMM 5.2. User manual

Check whethe only Q-H relations are supported or also Q-Q relations (overflow_char.kind_overflow_char

[sjib]

• I am not sure if storage curves are supported in VSA-DSS.

@sjib Are they supported? Do they exist in QGEP?

What do you mean with storage curves? Do you mean hydr_geom_relation that describes the Relation between wetted section, wetted surface and height in a wastewater_node (e.g. bassin with special shape?)

[tproduit]

Feedback from technical user group (2022.05.18) In the corresponding QGIS form a tab "overview" could be created to ease the exploration.

[ponceta]

@TriformMoritz is there anything more action to do here?