Add new shape for the North sea

[OnnoEbbens]

No description provided.

[KeesdeVriesW]

good plan! Please include other Rijkswateren as well. My suggestion: IJsselmeer/ Markermeer, Noordzeekanaal&IJ, Nieuwe Waterweg and all getijde-components of Grote Wateren.

[OnnoEbbens]

I found this WFS server from RWS that has the shapes we need. Using the existing nlmod function it is fairly easy to load this data.

url = "https://geo.rijkswaterstaat.nl/services/ogc/gdr/omgevingswet/ows?service=WFS"
layer = 'omgevingswet:oppervlaktewaterlichamen_rijk'
extent = dims.get_extent(ds)
gdf_swater = nlmod.read.webservices.wfs(url, layer, extent=extent)

The only difficult part is to find the right layer. The layers related to surface water are:

• 'grote_rivieren_bergend_deel_rivierbed',
• 'grote_rivieren_rivierbed',
• 'grote_rivieren_stroomvoerend_deel_rivierbed',
• 'kanalen_beperkingengebied_rijk',
• 'kustfundament_rijk',
• 'noordzee_beperkingengebied_rijk',
• 'noordzee_buiten_zone_dv_lat_beperkingengebied_rijk',
• 'oppervlaktewater_geen_kanaal_beperkingengebied_rijk',
• 'oppervlaktewaterlichamen_rijk'

I think it is nice to combine this data into a single shapefile with the surface waters suggested by @KeesdeVriesW. If someone can do this, the geopackages of these layers can be found below
geopackages_rws_oppwater.zip

[dbrakenhoff]

Partially solved by #242 where the cells with sea are derived from the DTM.

Keeping this issue open to add function to obtain the shapefile @OnnoEbbens proposed. Once this is done, we should remove the old shapefile.