1. Hydrological Feature coding
Take 2
By Albrecht Wirthmann, GISCO, Eurostat

2. Structure of the presentation
Review of comments
Main Changes
Coding structure
Code segments
Summary of code segments
Implementation of coding

3. Comments of 4th WISE workshop
Distinction between hydrological code and Identifier
Normalize code
Avoid River Basin Districts as part of code
(Instability, management unit)
Geographic resolution of coding
Bifurcations
Karst phenomena

4. Main Changes Code only for hydrological features
Modified coding structure
Sea Region code, commencement code, entity type list modified
Additional rules for special phenomena

5. Hydrological Features codes
River (sub) basins
(Main) River segments
Lakes (with outlet, local depression)
Coastal Waters
Transitional Waters
River water bodies
Lake water bodies
Coastal water bodies
Transitional Water bodies
Groundwater bodies
Artificial water bodies
Canals

6. Identifiers Canals River water bodies Lake water bodies
Coastal water bodies
Transitional Water bodies
Groundwater bodies
Artificial water bodies
Monitoring Stations
Point, non-point sources
Discharge points

7. Relationship between Hydrological Code and Identifier
Features with Identifier will be complemented with hydrological code of the area in which they are located
Hydrological code as foreign key
Type of Relationship depends on Resolution

8. Identifiers Follow GIS guidance: MSET#1#2…#22
MS = 2 character Member State identifier, ISO Alpha-2 country codes
#1.. = an up to 22 character feature code that is unique within the Member State.
Hydrological code as foreign key

9. Code segments of hydrological code
Sea Region
River Basin commencement code
River basin
Entity Type
(Conditional lake code)

10. Code Segment Sea Region
Identification of a sea region,
Modified Eco Region
mandatory
One digit, fixed length
Values 1-9

11. Code Segment Sea Region

12. Code Segment Sea Region
Final delimitation of sea regions based on Art. 3 data submission
Sea region boundaries at basin or RBD boundaries
Application by EC

13. Code Segment Sea Region

14. Commencement code segment
Commencement of river basin and coastal catchments
Covers entire territory of Europe
Unique in a sea region
3 digits, fixed length
Values
mandatory
Application should follow Pfafstetter principles
Application by EC

15. Commencement code segment

16. Code segment River Basin
Identification of major catchment
Identification of the river (sub)basin
Pfafstetter coding principles
1-11 digits, variable length
Values
mandatory
Spatial Resolution
1000 km² / 4000 km² within / outside EU
Introduction of certain level

17. Code segment River Basin42 44 46 48
Sea
Sub -
basin 26 43 45 47 49 41
Inter
basin 21 22 24 26 28 2 3 1 23 25 27 29 21

18. Code segment River Basin
462
464
466
461
463
465
467 42 44 48
Sea 43 45 47 49 41
262
264
266
261
263
265
267 22 24 28 2 3 1
Sub -
basins 26x 23 25 27 29 21

19. Code segment River Basin
Lakes
Connected to river network
Pfafstetter code of outlet
Not connected to river network
Additional identifier as last part of the hydrological code
Spatial Resolution: > 100 km²

20. Code segment River Basin
Connected
Lakes
One in- and outlet 2 3 4 5
Lake
code : -
015 25 LE

21. Code segment River Basin
Connected
Lakes
Multiple inlets 22 23 24 26 25 27
Lake code: LE

22. Code segment River Basin
Code Lake A: LE-01
Code Lake B: LE-02 22 23 24 25 A B
Lakes in local depressions

23. Code segment Lake ID Identifier of lakes in local depressions
Conditional segment for identifying lakes within a river basin
Append after entity type
conditional
2 digits, fixed length
Values: 01-99

24. Code segment Entity Type
Identification of coded feature
mandatory
2 characters, fixed size
Values ..

25. Code segment Entity Type
Entity type Values
BA River Basin
RS River Segment
RB River Segment; minor branch of bifurcation
RU River Segment; underground in Karst areas
LE Lake
LP Perennial Lake (in Karst areas)
CW Coastal Water
TW Transitional Water

26. Special Phenomena
Bifurcations
Karst phenomena
Canals

27. Special Phenomena Bifurcations
Lateral branches are coded in the same way as the other rvier features
Fictitious separation at divide
Code determined at confluence
Minor branches assigned with special entity type value

28. Special Phenomena Bifurcations Conceptual Separation 4-015-22RSRB RS

29. Special Phenomena Karst Specific entity type values for
Rivers flowing underground
Perennial lakes
If underground flow not identifiable, underground part of river not mapped, RS entity type value to be used for surface part

30. Special Phenomena Canals Canalized rivers part of river system
Canals not following natural drainage
Identifier
Hydrological code as foreign key
Split of canal when crossing river basin

31. Summary of code segments
Value type
Min., Max. Length
Sea Region
Number 1
Commencement code segment 3
River (basin) (Pfafstetter)
1-11
Entity Type
Character 2
Conditional unique string for lakes
0, 2
Maximum total length
7, 19

32. Application of coding Needs
River Network
Catchment areas
Sea areas
Topology
Connected at nodes
Flow information
Defined resolution
International
Topologically integrated

33. Application of coding Scenario 1
Application of code by EC
Reported River Network not suitable
CCM
Issue of application of code to national datasets

34. Application of coding Scenario 2
Application of code by MS
Reported River Network not suitable
Use of national or IRBD datasets
Issue of application of code to CCM
Issue of riverbasins outside EU

35. Application of coding Scenario 3
Mixed approach
Application of code by MS where suitable datasets exist
Reporting of river basins and rivers with codes to be repeated
Transfer of code to CCM by EC
Usage of CCM for other areas
Transfer of code to national data (if existing)
Integration of both datasets necessary
Identification of areas by RBD and basins

36. Approach Evaluation of Art. 3 deliveries (river basins)
Delineation of sea region borders by EC
Identification of regions and assignment of commencement code segment
Assignment of Pfafstetter code segment by MS / CA / EC by river basin
Coordination, quality assurance by EC
Rules for aggregation necessary?
Software tools for assignment useful?

37. Questions Stick to Eco regions for the sea for Sea Region coding
Minimum size of subbasins / hydrological level