Grouping

Annexes - Data analysis - 3rd cycle

This section contains some of the exploratory data analysis that supported the revision of the data model.

It is not relevant for the understanding of the proposed model, but may be informative for data providers involved in the testing phase of the 4th cycle dataflows.

About the EEA discodata service

The example queries can be executed interactively in the EEA discodata service.
Note that some queries may timeout.
If you need to analyse the entire European dataset, download it in CSV format.
For example, the link https://discodata.eea.europa.eu/download/WISE_WFD/v2r1/GWB_GroundWaterBody downloads the data of the [WISE_WFD].[v2r1].[GWB_GroundWaterBody] table.

The data for this section can be derived from the following tables:

• [WISE_WFD].[v2r1].[SWB_SurfaceWaterBody_QualityElement]

• [WISE_WFD].[v2r1].[SWB_SurfaceWaterBody_QualityElement_qeGrouping]

• [WISE_WFD].[v2r1].[Monitoring_MonitoringSite_ChemicalEcologicalQuantitativeMonitoring]

• Published WISE Spatial datasets

To simplify the analysis, the information was extracted into a graph structure with nodes representing water bodies, and edges representing the link between monitored water bodies and the water bodies with grouping.

Show description

Example 37 Grouping - description of the tables used for analysis

SELECT [countryCode]
      ,[fromNodeId]   -- water body providing the monitoring data
      ,[toNodeId]     -- water body being assessed
      ,[qeCode]       -- quality element being assessed 
  FROM [edges]

-- Water bodies as "nodes"
SELECT [countryCode]    -- country code
      ,[nodeId]         -- water body identifier
      ,[waterCategory]  -- RW, LW, TW, CW
      ,[lat]            -- latitude in WGS84
      ,[lon]            -- longitude in WGS84
      ,[outDegree]      -- number of water body X QE using monitoring data from this water body
      ,[inDegree]       -- number of water body X QE providing monitoring data for the assessment of this water body
  FROM [nodes]

-- "nodes" with qeStatus plus derived information
SELECT [countryCode]      -- country code
      ,[nodeId]           -- water body identifier
      ,[waterCategory]    -- water body category
      ,[qeCode]           -- quality element code
      ,[qeStatus]         -- quality element status ('1','2','3','4','5','unknown',...)
      ,[assessmentMethod] -- assessment method
      ,[outDegree]        -- number of water bodies that are assessed based on data from this water body for the quality element
      ,[inDegree]         -- number of water bodies provide data for the assessment of this water body and quality element
      ,[isMonitored]      -- Monitoring schema: 1 if the water body is monitored for the quality element, 0 otherwise,
  FROM [nodes_qeStatus]

-- data from the Monitoring schema reporting
SELECT [countryCode] -- country code
      ,[nodeId]      -- water body identifier
      ,[qeCode]      -- quality element code
      ,[isMonitored] -- Monitoring schema: 1 if the water body is monitored for the quality element, 0 otherwise 
  FROM [nodes_qeCode_isMonitored]

Grouping and quality elements

“Reporting on the status assessment of Quality Elements (QEs) is expected not only where monitoring results are available for specific water bodies but also for all water bodies for which this information is available (e.g. through grouping). A status value should, therefore, be given for each of the relevant QEs that have been assessed for the water body and subsequently used to classify the ecological status or potential of the water body.” – From the WFD Reporting Guidance 2022

Grouping with water bodies that were not assessed by monitoring

“Schema element: qeGrouping
Guidance on completion of schema element: Conditional. If no monitoring data is available for this quality element in this surface water body and status has been derived through grouping by extrapolating monitoring data from other surface water bodies, indicate the codes of the surface water bodies which have been monitored and used for the classification of this water body. For example, if the status of surface water body A has been determined by extrapolating monitoring data from surface water bodies B and C, then the euSurfaceWaterBodyCode for surface water bodies B and C should be reported in this element. Quality checks: Conditional check: Report if and only if qeMonitoringResults is ‘Grouping’. Within-schema check: Each water body code reported must be identical to a thematicIdIdentifier reported for surface water bodies in spatial data. Cross-schema check: The SurfaceWaterBodyCode belongs to a different RBD. Please check that for that euSurfaceWaterBodyCode and qeCode, the value of qeMonitoringResults is ‘Grouping’. Cross-schema check: If a euSurfaceWaterBodyCode is valid and belongs to the same RBD, then the following condition must be true: for that euSurfaceWaterBodyCode and qeCode, the value of qeMonitoringResults must be ‘Grouping’.” – From the WFD Reporting Guidance 2022

The “Cross-schema check” specifications are incorrect and inconsistent with the “Guidance on completion of schema element” that requires the extrapolation to be made from a water body with qeMonitoringResults = ‘Monitoring’ (and not ‘Grouping’). The implementation of the quality control (i.e. the code base) was imperfect:

• For grouping across water bodies in different river basin districts, only an indicative ERROR could be flagged (because the reporting was done at RBD scale). The resulting inconsistencies affect 11861 of 230115 records (5.2%), mostly in Greece.

• For grouping with water bodies in the same river basin district, the inconsistencies affect only 669 records (0.3%). The cause was possibly a failure in the quality control process, but it is not possible to trace it back at this point.

Show results

Table 72 Grouping - inconsistencies due to inadequate quality control - 3rd cycle

country	qeCode	wb in different RBD	wb in same RBD	water bodies
BE	QE1-1 - Phytoplankton	0	1	1
BE	QE3-1-6-2 - Phosphorus conditions	0	1	1
BG	QE1-2-3 - Macrophytes	0	2	2
BG	QE1-2-4 - Phytobenthos	0	1	1
BG	QE1-4 - Fish	0	1	1
EL	QE1-1 - Phytoplankton	0	2	2
EL	QE1-2-1 - Macroalgae	0	2	2
EL	QE1-2-2 - Angiosperms	0	9	9
EL	QE1-2-3 - Macrophytes	1577	1	1578
EL	QE1-2-4 - Phytobenthos	985	26	1011
EL	QE1-3 - Benthic invertebrates	1155	59	1214
EL	QE1-4 - Fish	1100	53	1153
EL	QE2-2 - River continuity conditions	1801	78	1879
EL	QE2-3 - Morphological conditions	977	104	1081
EL	QE3-1-1 - Transparency conditions	0	76	76
EL	QE3-1-3 - Oxygenation conditions	931	6	937
EL	QE3-1-6-1 - Nitrogen conditions	931	6	937
EL	QE3-1-6-2 - Phosphorus conditions	821	6	827
EL	QE3-3 - River Basin Specific Pollutants	1574	22	1596
ES	QE1-2-3 - Macrophytes	0	13	13
ES	QE1-2-4 - Phytobenthos	0	6	6
ES	QE1-3 - Benthic invertebrates	0	5	5
ES	QE1-4 - Fish	0	1	1
ES	QE2-3 - Morphological conditions	0	3	3
ES	QE3-1-3 - Oxygenation conditions	0	4	4
ES	QE3-1-4 - Salinity conditions	0	6	6
ES	QE3-1-5 - Acidification status	0	2	2
ES	QE3-3 - River Basin Specific Pollutants	0	3	3
HR	QE1-2-1 - Macroalgae	0	2	2
IE	QE1-2 - Other aquatic flora	0	36	36
IT	QE1-2-3 - Macrophytes	1	5	6
IT	QE1-2-4 - Phytobenthos	0	3	3
IT	QE1-3 - Benthic invertebrates	1	7	8
IT	QE1-4 - Fish	0	4	4
IT	QE2-1 - Hydrological or tidal regime	1	1	2
IT	QE2-2 - River continuity conditions	0	1	1
IT	QE2-3 - Morphological conditions	0	1	1
IT	QE3-1-2 - Thermal conditions	0	1	1
IT	QE3-1-3 - Oxygenation conditions	1	3	4
IT	QE3-1-5 - Acidification status	0	1	1
IT	QE3-1-6-1 - Nitrogen conditions	1	3	4
IT	QE3-1-6-2 - Phosphorus conditions	1	3	4
IT	QE3-3 - River Basin Specific Pollutants	3	7	10
LT	QE2-2 - River continuity conditions	0	1	1
LT	QE3-1-3 - Oxygenation conditions	0	1	1
LV	QE3-1-6-1 - Nitrogen conditions	0	1	1
LV	QE3-1-6-2 - Phosphorus conditions	0	1	1
SE	QE1-1 - Phytoplankton	0	7	7
SE	QE1-4 - Fish	0	3	3
SE	QE3-1-1 - Transparency conditions	0	4	4
SE	QE3-1-5 - Acidification status	0	58	58
SE	QE3-1-6-2 - Phosphorus conditions	0	14	14
SK	QE3-3 - River Basin Specific Pollutants	0	2	2

Show code

Example 38 Grouping - inconsistencies due to inadequate quality control - 3rd cycle

SELECT [countryCode]
      ,[qeCode]
      ,SUM(IIF([to_euRBDCode] != [from_euRBDCode],1,0)) AS [numberInDifferentBasin]
      ,SUM(IIF([to_euRBDCode] = [from_euRBDCode],1,0)) AS [numberInSameBasin]
      ,COUNT(*) AS [totalNumber]
      FROM 
(SELECT -- toNode

       a.[countryCode]
      ,a.[qeCode]

      ,a.[euRBDCode] as [to_euRBDCode]
      ,a.[euSurfaceWaterBodyCode] as [to_euSurfaceWaterBodyCode]
      ,a.[surfaceWaterBodyCategory] as [to_surfaceWaterBodyCategory]
      ,a.[qeMonitoringResults] as [to_qeMonitoringResults]
      ,a.[qeGrouping] as [to_qeGrouping]
      
      -- fromNode
      ,b.[euRBDCode] as [from_euRBDCode]
      ,b.[surfaceWaterBodyCategory] as [from_surfaceWaterBodyCategory]
      ,b.[qeCode] as [from_qeCode]
      ,b.[qeMonitoringResults] as [from_qeMonitoringResults]
      ,b.[qeGrouping] as [from_qeGrouping]
      
  FROM [WISE_WFD].[v2r1].[SWB_SurfaceWaterBody_QualityElement_qeGrouping] a
  
  LEFT JOIN [WISE_SOW].[v2r1].[SWB_SurfaceWaterBody_QualityElement_qeGrouping] b
    ON a.[countryCode] = b.[countryCode]
    AND a.[qeGrouping] = b.[euSurfaceWaterBodyCode]
    AND a.[qeCode] = b.[qeCode]
    AND a.[cYear] = b.[cYear] 
    
  WHERE a.[cYear] = 2022 AND a.[hasDescriptiveData] = 1
  AND a.[qeMonitoringResults] = 'Grouping' 
  --AND a.[qeCode] != 'QE3-3 - River Basin Specific Pollutants'
  ) a

  WHERE [from_qeMonitoringResults] != 'Monitoring'
  GROUP BY [countryCode], [qeCode]
  ORDER BY [countryCode], [qeCode]

Inconsistencies with the data in the Monitoring schema

The information provided in the Monitoring schema might have provided an alternative data source to understand which water bodies where actually monitored.

However, in that specific case there was no quality control specified between the grouping data and the Monitoring schema data.

Therefore, and as the results of the Table 73 show, the inconsistencies between the grouping data and the monitoring schema data are high. According to the grouping data, 3550 monitored water bodies had their data extrapolated for the assessment of water bodies not monitored. However, for 2225 of those water bodies (62%) there is no evidence (in the Monitoring schema) of the water body having been monitored for (at least one of) the expected Quality Element.

Table 73 Grouping - inconsistencies with the Monitoring schema data - 3rd cycle

qeCode	countries	waterBodies	with inconsistency	percentage
QE1-1 - Phytoplankton	13	247	29	11
QE1-2 - Other aquatic flora	4	45	22	48
QE1-2-1 - Macroalgae	3	29	3	10
QE1-2-2 - Angiosperms	3	44	5	11
QE1-2-3 - Macrophytes	11	684	125	18
QE1-2-4 - Phytobenthos	11	1643	351	21
QE1-3 - Benthic invertebrates	15	1875	306	16
QE1-4 - Fish	14	1022	108	10
QE2-1 - Hydrological or tidal regime	6	250	12	4
QE2-2 - River continuity conditions	7	325	99	30
QE2-3 - Morphological conditions	8	441	126	28
QE3-1-1 - Transparency conditions	8	66	55	83
QE3-1-2 - Thermal conditions	7	386	171	44
QE3-1-3 - Oxygenation conditions	16	1616	1034	63
QE3-1-4 - Salinity conditions	9	374	161	43
QE3-1-5 - Acidification status	11	644	369	57
QE3-1-6-1 - Nitrogen conditions	16	1717	1058	61
QE3-1-6-2 - Phosphorus conditions	17	1800	1189	66
QE3-3 - River Basin Specific Pollutants	13	1820	544	29
«all»	19	3550	2225	62

Show code

Example 39 Grouping_water_bodies_grouped_with_themselves_3rdCycle_Table

SELECT [qeCode]
      ,COUNT(DISTINCT [countryCode]) AS [numberOfCountries]
      ,COUNT(DISTINCT [nodeId]) AS [numberOfWaterBodies]
      ,COUNT(DISTINCT IIF([isMonitored] = 0,[nodeId],NULL)) AS [number_withInconsistency]
      ,COUNT(DISTINCT IIF([isMonitored] = 0,[nodeId],NULL))*100/ COUNT(DISTINCT [nodeId]) AS [percentage_withInconsistency]
  FROM [nodes_qeStatus]
  WHERE NOT ([outDegree] > 0 AND [inDegree] > 0)
  AND [outDegree] > 0
  GROUP BY [qeCode] WITH ROLLUP
  ORDER BY [qeCode]

Basic errors

Table 74 Grouping - water bodies grouped with themselves - 3rd cycle

countryCode	from	to	qeCode
IE	IEWE_160_0700	IEWE_160_0700	QE1-2 - Other aquatic flora
IT	IT19CW04794	IT19CW04794	QE3-1-3 - Oxygenation conditions
IT	IT19CW04794	IT19CW04794	QE3-1-6-1 - Nitrogen conditions
IT	IT19CW04794	IT19CW04794	QE3-1-6-2 - Phosphorus conditions
IT	ITF015RWN011012156SABATO18SS3	ITF015RWN011012156SABATO18SS3	QE1-2-4 - Phytobenthos
IT	ITF015RWN011012156SABATO18SS3	ITF015RWN011012156SABATO18SS3	QE1-3 - Benthic invertebrates

Show code

Example 40 Grouping - water bodies grouped with themselves - 3rd cycle

SELECT [countryCode]
      ,[fromNodeId]
      ,[toNodeId]
      ,[qeCode]
  FROM [edges]
  WHERE [fromNodeId] = [toNodeId];

Table 75 Grouping - water bodies both receiving and providing data of a given quality element - 3rd cycle

country	nodeId	waterCategory	qeCode	qeStatus	outDegree	inDegree	isMonitored
IE	IESW_060_0100	TW	QE1-2 - Other aquatic flora	3	1	1	0
IE	IEWE_160_0700	CW	QE1-2 - Other aquatic flora	3	3	1	0
IT	IT09CI_R000OM173CA	RW	QE3-1-6-2 - Phosphorus conditions	2	1	1	0
IT	IT09CI_R000OM173CA	RW	QE3-1-3 - Oxygenation conditions	2	1	1	0
IT	IT09CI_R000OM173CA	RW	QE3-1-6-1 - Nitrogen conditions	2	1	1	0
IT	IT10N0100121AF	RW	QE3-1-5 - Acidification status	1	1	1	0
IT	IT10N0100121AF	RW	QE3-1-2 - Thermal conditions	1	1	1	0
IT	IT10N0100121AF	RW	QE3-1-3 - Oxygenation conditions	1	1	1	0
IT	IT10N0100121AF	RW	QE1-3 - Benthic invertebrates	2	1	1	0
IT	IT10N0100121AF	RW	QE3-1-6-2 - Phosphorus conditions	1	1	1	0
IT	IT10N0100121AF	RW	QE3-1-6-1 - Nitrogen conditions	1	1	1	0
IT	IT10N0100121AF	RW	QE3-3 - River Basin Specific Pollutants	1	1	1	0
IT	IT19CW04794	CW	QE3-1-6-2 - Phosphorus conditions	2	1	1	0
IT	IT19CW04794	CW	QE3-3 - River Basin Specific Pollutants	2	1	1	0
IT	IT19CW04794	CW	QE3-1-3 - Oxygenation conditions	2	1	1	0
IT	IT19CW04794	CW	QE3-1-6-1 - Nitrogen conditions	2	1	1	0
IT	ITF015RWN011012156SABATO18SS3	RW	QE1-3 - Benthic invertebrates	5	1	1	0
IT	ITF015RWN011012156SABATO18SS3	RW	QE1-2-4 - Phytobenthos	1	1	1	0
HR	HRJMO013	CW	QE1-2-1 - Macroalgae	1	2	1	1
IT	IT09CI_R000OM173CA	RW	QE3-3 - River Basin Specific Pollutants	3	1	1	1

Show code

Example 41 Grouping - water bodies both receiving and providing data - 3rd cycle

  SELECT [countryCode]
      ,[nodeId]
      ,[waterCategory]
      ,[qeCode]
      ,[qeStatus]
      ,[outDegree]
      ,[inDegree]
      ,[isMonitored]
  FROM [WISE_Sandbox].[tmp_grouping].[nodes_qeStatus]
  WHERE [outDegree] > 0 AND [inDegree] > 0
  ORDER BY [isMonitored],[nodeId];

Subset of countries for further analysis

The proportion of problematic records is relatively low: 1081 out of 88156 records (1.2%) and 343 out of 16958 water bodies (2%).

Nevertheless, a decision was taken to further analyse only a subset of 8 countries that have data regarding grouping where none of above issues was detected.

From the subset of countries:

1. Austria, Romania and Portugal have the highest absolute number of water bodies where grouping was applied,

2. Austria uses several monitored water bodies for the assessment of a given water body. Other countries reported similar approaches (EL,ES,IT,SE,SK), but were not included in the subset, due to data quality issues.

3. The remaining countries use only one monitored water body for each water body assessed via grouping. Monitored water bodies may supply data for the assessment of several non-monitored water bodies.

Show results

Table 76 Grouping - Countries with grouping data, and no detected issues - 3rd cycle

country	qeCount	wbMonitoring	wbGrouping	wbEither	maxOutDegree	maxInDegree
AT	6	1278	8002	8076	1718	25
CZ	11	24	29	53	3	1
DK	9	10	13	23	3	1
HU	6	72	78	149	2	1
NL	11	31	61	88	14	1
PT	16	148	228	376	7	1
RO	15	318	1497	1760	145	1
SI	6	2	3	5	2	1

Show code

Example 42 Grouping - Countries with available data, and no detected issues - 3rd cycle

SELECT [countryCode]
      ,COUNT(DISTINCT qeCode) AS [qeCount]
      ,COUNT(DISTINCT IIF([outDegree] > 0, nodeId,NULL)) AS [wbMonitoring]
      ,COUNT(DISTINCT IIF([inDegree] > 0, nodeId,NULL))  AS [wbGrouping]
      ,COUNT(DISTINCT nodeId)  AS [wbEither]
      ,MAX(outDegree) AS [maxOutDegree]
      ,MAX(inDegree) AS [maxInDegree]
  FROM [nodes_qeStatus]
  WHERE [countryCode] NOT IN
  (
    SELECT [countryCode]
          -- ,COUNT(*) as [count]
      FROM [WISE_Sandbox].[tmp_grouping].[nodes_qeStatus]
      WHERE ([outDegree] > 0 AND [inDegree] > 0)      -- error
      OR ([outDegree] > 0 AND [assessmentMethod] != 'Monitoring')  -- also an error
      GROUP BY [countryCode] )
  GROUP BY [countryCode]