1. WISE-GIS WG Koblenz 18-19 May 2009 1 Rationales for a reference GIS for Hydrosystems. The ECRINS development E uropean C atchments and RI vers N etwork S ystem Philippe Crouzet EEA With support from Walter Simonazzi (ETC/LUSI) and EEA IDS staff

2. WISE-GIS WG Koblenz 18-19 May 2009 2 Reference GIS for hydrosystems is prerequisite to producing accurate and representative assessments as well as offering host to legal reporting. To this end, and considering the strong relationships between land, water and economy the system must consist in: Calculable and nested catchments. Drained by relevant, nested and routed rivers, Completed by standing bodies (lakes, dams), Related to monitoring and usage points However rivers lakes, dams and points are geographical objects than can be seen, whereas catchments are concepts that need to be modelled.

3. WISE-GIS WG Koblenz 18-19 May 2009 3 River fragmentation (SEBI component): The Loire example (all known dams) Historical development Why not applying at the EU level? Model exists and is validated, Dams are placed (Eldred2) Because no calculable river system!

4. WISE-GIS WG Koblenz 18-19 May 2009 4 River Sea Watershed land Dam WWTP

5. WISE-GIS WG Koblenz 18-19 May 2009 5 Production starts from reality, e.g. rivers from maps What geographers see and draw is not what is needed for building reference system. Requirements are to: Clarify conceptual model, mitigated by data source affordability Identify objects: give usable and unique IDs Group by logical consistency: set watersheds Select what is important: choose homogeneous levels, Relate what relates to what: connect, Organise dependencies: route Make it understandable and improvable: document

6. WISE-GIS WG Koblenz 18-19 May 2009 6 Conceptual modelling Goals: Geometrical accuracy, homogeneous and comprehensive coverage, Complete topology “doable” with existing data sets and free of charges Stepwise model development (foreseeing Inspire implementation) Designed solution Operational scale 1/250k Based on “functional units”: the Functional elementary catchment (FEC) Made from CCM JRC, by post-processing and assimilation of other sources (ERM, Eldred32, etc.)

7. WISE-GIS WG Koblenz 18-19 May 2009 7 Selecting sources for building a system: Precision antagonist of accuracy? Highly geometrically precise national maps are too detailed for EU purposes Can provide by contrast attribute information on secondary (primary?) objects once structured and accurate functional network has been set Very detailed, but unusable Processing inserts coherence at the expense of limited precision losses

8. WISE-GIS WG Koblenz 18-19 May 2009 8 Concepts and production method: data source selection ItemCCM (v2.1)Geographical (ERM, etc.) AccuracyGood for large only Country depending Detailed objectsErraticAccurate and comprehensive HomogeneityGood if processedCountry depending CalculabilityFull (after processing) Often not DisseminationFreeLicensed

9. WISE-GIS WG Koblenz 18-19 May 2009 9 Mimicking suitable reality with FECs: Functional elementary catchments Definition: hydrological catchments centred on ~100 km 2 area, Built from CCM 2.1, (i.e: from MODEL) Hydrologically consistent (U/D dependencies, inside basins, etc.) In manageable number True containers of rivers Fitted by a single main drain Main drain (from CCM) FEC limits All rivers (here: national data set)

10. WISE-GIS WG Koblenz 18-19 May 2009 10 Solving CCM intrinsic problems CCM is a modelled catchment and network system: Smallest objects possibly inaccurate because DEM resolution and ArcHydro model, Being a model, it is fully connected and calculable, but objects are defined by the model, not by the envisaged uses Being a model it lack gazetting Being calculable, it can be improved by data processing, provided solutions are defined and implemented and recomputed in an improvement cycle Completely free of charges

11. WISE-GIS WG Koblenz 18-19 May 2009 11 Solving River Basin Districts oddness Districts are administrative management areas presented as if they were river basins. When used to build a river system They extend over sea, They don’t respect basin watershed They show large “holes” (corrected in further versions) Hence, adjustments are needed-> Functional RBDs

12. WISE-GIS WG Koblenz 18-19 May 2009 12 Building the FECS Elementary CCM catchments are very small, numerous (~2 millions), and not directly usable because the large range of sizes (few ha to 100’s km 2 ) FEC making consisted in implementing rules of aggregation into: Coastal basins and Continental FECS by building and populating adequate envelopes: the algorithm is based on Strahler levels, cumulated size, presence of basins and scoring criteria inside larger catchments Both are then merged into a FEC layer

13. WISE-GIS WG Koblenz 18-19 May 2009 13 Connection and routing Connection tells that A → B; B → C; D → C, etc. Routing tells is that A, B and C belong to river “River 1” and D to “River 2” Connection provided by CCM, routing is partly populated, hence: Name is given priority 1 in routing ID, The identified long drains are, Third are connection algorithm on catchment area (implementation on going) 1: Select end nodes 2: Define largest catchment area 3: loop on rivers already set

14. WISE-GIS WG Koblenz 18-19 May 2009 14 Aggregation watershedss Compute ”Functional RBDs” from the reported RBDs: Collection of FECS belonging to homogeneous basins inside the RBD Difficult process because high heterogeneity of RBD delineations Sub-units not ready enough yet Sub-catchments made to match Functional RBDs where RBDs exist Clipped (limited by shoreline) international RBDs The Functional RBDs contain the large basins Large basins (the FEC largest envelopes)

15. WISE-GIS WG Koblenz 18-19 May 2009 15 Aggregation watersheds Target is to cluster FEC (mean size ~100km2) into larger watersheds (~10,000 to 35,000 km2 for example) Being fully consistent with larges basins AND RBDs, Having hydrological relevance Which design and production are affordable Design algorithm derived from FEC envelopes making, adjusted: No natural envelopes, Larger target size makes results more sensitive to tuning Sub-basins (largest aggregation catchments) FRBDs reported in violet. Target 10,000 km2, 1470 objects

16. WISE-GIS WG Koblenz 18-19 May 2009 16 Pending issues (aggregation watersheds) When lowering the area target, too large catchments become a problem, “Too large” catchments are those that cannot be exploded by the simple algorithm used (selecting Strahler levels 6/7) Supplementary algorithm to cluster differentially Strahler level 5 in underway. Guadiana: RBD=sub- basin Andalucia Atlantic basins RBD= 6 sub-basin Strahler level 5 in the Guadiana basin

17. WISE-GIS WG Koblenz 18-19 May 2009 17 Lakes and dams Lakes pose serious problems because not linked to the rivers or the watersheds: CCM source quite homogeneous, locally inaccurate ERM source extremely heterogeneous and incomplete A single data set created (~180,000 lakes) by merging and connecting to the outlet river Experience suggests high difficulty in relating lakes and rivers by nodes, because conflicts between topology and geometry. River segment preferred since more operational. Types of relationships exemplified: lake on the main drain, lake out of main drain, endoreic lake

18. WISE-GIS WG Koblenz 18-19 May 2009 18 Dams Data sources: No CCM data source, ERM source heterogeneity beyond imagination and not documented (only point / multi line, no ID, no name, etc.) Eldred2 data source only for large dams, not totally geolocalised. Very complex processing carried out to sort out ERM dams into a single feature class and merging with Eldred (with priority to Eldred2) Available end May With WFD reporting, source for lake documentation

19. WISE-GIS WG Koblenz 18-19 May 2009 19 Documenting and data Documents are issued with β versions of datasets Report on the principles and the making of FECS, disseminated with FECs v2 β, Report on the main drains disseminated with main drains v1 β Report on aggregation catchments done Report on lakes and dams under preparation Disseminated data bases: CCM Source is 18 databases for catchments, 18 for rivers and nodes, 2 summary databases (40 DB) that require 96 intermediate processing databases (reallocated, export, result and service) plus application. ERM source is 2 lakes layer, 4 for dams, 2 for rivers Eldred2 unique source Results are in 1 database for FECs, 1 for river and nodes and 1 summary (Functional RBDs, aggregation catchments, etc), 1 for lakes and 1 for obstacles (possibly merged if possible), in CIRCA (IG: Water accounts and river fragmentation).

20. WISE-GIS WG Koblenz 18-19 May 2009 20 Achievement (16 /05/2009) StepConceptsPreparatory data Production programme ProductionPopulating / Gazeeting Functional elementary catchments TestedTested, repeated TestedDone (beta)Document, rainfall per FEC RiversTestedTested, repeated TestedDone (beta), headwaters to complete Document, proposed for reporting Functional RBDsTestedTested, repeated TesteddoneDocumented, WAccounts Aggregation catchments Tested doneSame as above Lakes & dams integration Tested Underway Analysing errors and maintaining AnalysedTestedUnderwayCorrecting under analysis Not started

21. WISE-GIS WG Koblenz 18-19 May 2009 21 Perspectives The β versions are under processing for making the « broad-brush » water accounts, Sorting out the whole set of rivers by FEC minus main drain is data source for « Small rivers » assessment, FECs connectivity and main routing is data source for stratified assessment of water quality, etc.

22. WISE-GIS WG Koblenz 18-19 May 2009 22 Immediate applications WFD “main rivers” are defined as those draining more than 500 km2 (or any other combination). The response is instantaneous: And can be use as selection mask to extract data from other layers, if greater precision is required, or complementary attributes

23. WISE-GIS WG Koblenz 18-19 May 2009 23 Applications for the next SoER 2010 Populating data Population per catchment / per cities withinn catchments ECVs per catchment (done for summary data ATEAM), on going for MARS data) Applications Water asset accounts / water balances underway Catchment stratification by drivers, altitude, etc. possible -> assessing water quality trends vs. drivers underway, (cf. 2007 methodology) River fragmentation by dams underway for amphibiotic (SEBI, liaising with hydropower) Small rivers issue: risks of dry-out Support for WFD reporting: underway

24. WISE-GIS WG Koblenz 18-19 May 2009 24 Ingredients for “small rivers” Documented observation point on “dry-out” events (more than 1,000 on 2 NUTS2)

25. WISE-GIS WG Koblenz 18-19 May 2009 25 Envisaged developments Currently: Seek for minor errors correction, and process a β3 version end 2009 Correct errors related to CCM model (e.g. karstic areas) Planned Integrate WFD reports to feed-back quality and inform on reporting issues Stepwise gazette the rivers names and reprocess routes Prepare a “CCM3” based ECRINS2 in 2011, with systematic input from geographical data at the source of hydro modelling

26. WISE-GIS WG Koblenz 18-19 May 2009 26 Pending issues (aggregation watersheds) When lowering the area target, too large catchments become a problem, “Too large” catchments are those that cannot be exploded by the simple algorithm used (selecting Strahler levels 6/7) Supplementary algorithm to cluster differentially Strahler level 5 in underway.

27. WISE-GIS WG Koblenz 18-19 May 2009 27 Thanks for your attention Data on CIRCA (ask for IG inscription) mailto:philippe.crouzet@eea.europa.eu