Forcing

The regional models and the main water system share their forcing, in ribasim_nl.regional_model, for 2017 up to 2020. The run of the coupled model covers the first 2 of these 3 years.

flowchart LR
  lhm["LHM 4.3 results<br>LHM_433_budgets_update_makkink"] --> meteo["Precipitation,<br>evaporation"]
  lhm --> budgets["Drainage, infiltration,<br>surface runoff, sprinkling"]
  meteo --> basin["Basin / time"]
  budgets --> basin
  foreign["Measured foreign inflows<br>BuitenlandseAanvoer"] --> flow["FlowBoundary / time"]
  rwzi["RWZI model<br>Z-info, RwziBase"] --> flow
  flow --> model["Regional model"]
  basin --> model
  model --> fractions["LHM fractions<br>for tracing water"]

Four charts over 2017 and 2018: precipitation with sharp peaks, evaporation peaking in summer, drainage in winter, and infiltration in summer. — The forcing of a Basin of Delfland in the coupled run. Precipitation and evaporation act on the water surface, and drainage and infiltration exchange with the groundwater.

Precipitation and evaporation

Both come from the results of LHM 4.3, averaged per Basin, see ribasim_nl.set_forcing. Evaporation is the Makkink reference evaporation times the open water factor of Mozart, by month and decade. An LHM day starts at 09:00 in model time, so the forcing starts on the day before the start of the model.

Drainage, infiltration and runoff

ribasim_nl.assign_offline_budgets adds the MODFLOW-MetaSWAP budgets of the LHM, summed per Basin: negative values become drainage, and positive values infiltration.

Budget	Goes to
`bdgriv_sys1`, `4`, `5`	doorgaand and hoofdwater Basins
`bdgriv_sys2`, `3`, `6`, `bdgdrn_sys1`, `2`, `3`	bergend Basins
`bdgqrun`	`surface_runoff`
`bdgpssw`, sprinkling	hoofdwater and doorgaand Basins in the gravity controlled models, bergend Basins in the level controlled models

The script writes the budgets to mfms_budgets.arrow, and a check of the assignment to results/assign_validation.png in the model folder.

Foreign inflows

Streams from Germany and Belgium enter as FlowBoundaries with meta_categorie “buitenlandse aanvoer”. src/ribasim_nl/ribasim_nl/data/buitenlandse_aanvoer.csv lists the 55 inflows, all in Brabantse Delta, De Dommel, Limburg, Rijn en IJssel and Vechtstromen. ribasim_nl.transboundary_inflow matches them to the boundaries by name and location, and sets measured daily values from Basisgegevens/BuitenlandseAanvoer, with gaps interpolated. Outside the measurements, or without any, the inflow is the constant in that table.

Wastewater

The stage rwzi makes a separate model with pipeline/create_rwzi_model.py, of one FlowBoundary per treatment plant, linked to a Terminal at its discharge point. The flow rates are daily influent from Z-info, or else the yearly values of RwziBase, spread evenly over the days.

flowchart LR
  a["RWZI FlowBoundary"] --> b["Junction, was the Terminal"]
  b --> c["Route into or<br>out of the Basin"]

merge_rwzi_model adds the plants that discharge in the model, within 100 m of a Basin that is not bergend, or 3000 m in the main water system, and removes the others. attach_rwzi_junctions then moves each Junction onto the nearest route into or out of its Basin.

Fractions

ribasim_nl.assign_lhm_fractions labels the water by its origin, such as precipitation, drainage, or the neighbouring authority. The main water system has the same fractions, with the Rhine at Lobith and the Meuse at Monsin as Rijn and Maas. The model then tracks these fractions through the network, and ribasim_nl.delwaq can use them for water quality with Delwaq.