Discussion Paper - Applying Earth observation to support ...€¦ · Earth observation (EO):...
Transcript of Discussion Paper - Applying Earth observation to support ...€¦ · Earth observation (EO):...
Applying Earth observation
to support the detection of
non-authorised water
abstractions
Discussion paper on the
development of Copernicus
tools and services
Report for the European Commission, DG Environment
Document information
CLIENT European Commission, DG Environment
CONTRACT
REFERENCE
070307/2013/SFRA/660810/ENV.C1 - under the Framework contract
ENV.D.I/FRA/2012/0014 “Framework contract to provide services to
support the development and implementation of EU freshwater
policies”
PROJECT NAME Applying Earth observation to detect non-authorised water
abstractions
PROJECT OFFICER Thomas Petitguyot
DATE 17 November 2014
AUTHORS Sarah Lockwood, Marion Sarteel, and Shailendra Mudgal
Bio by Deloitte
Dr. Anna Osann, Prof. Dr. Alfonso Calera
Universidad de Castilla-La Mancha (UCLM)
KEY CONTACTS Shailendra Mudgal
Or
Sarah Lockwood
Disclaimer:
The information and views set out in this report are those of the authors and do not necessarily reflect
the official opinion of the Commission. The Commission does not guarantee the accuracy of the data
included in this study. Neither the Commission nor any person acting on the Commission’s behalf may
be held responsible for the use which may be made of the information contained therein.
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Contents
Document information ..............................................................................................................................3
Glossary ....................................................................................................................................................3
1. Introduction ........................................................................................................................................5
1.1. Context ........................................................................................................................ 5
1.2. Objectives .................................................................................................................... 6
1.3. Approach ..................................................................................................................... 6
2. Opportunities from the use of EO for the detection of non-authorised water abstraction in the EU .7
2.1. Identified water managers’ needs for the detection and monitoring of water abstractions7
2.2. Potential of EO products for detecting and monitoring abstractions ........................... 7
2.3. EO applications for the monitoring of non-authorised water abstractions ................. 13
2.4. Possible range of complementary applications ......................................................... 14
2.5. Discussion of the potential of EO applications .......................................................... 15
3. Requirements for the detection of non-authorised abstractions and complementary applications 19
3.1. Technical requirements for the monitoring of water abstractions .............................. 19
3.2. Legal and administrative requirements for the detection of non-authorised abstractions21
3.3. Operational requirements .......................................................................................... 22
4. Current challenges at MS level ...................................................................................................... 23
4.1. EO technical capacity ................................................................................................ 23
4.2. Governance and political commitment ...................................................................... 27
4.3. Definition of water rights and availability of corresponding information .................... 28
4.4. Local data availability ................................................................................................ 28
4.5. Economic aspects...................................................................................................... 29
4.6. Summary ................................................................................................................... 30
5. Options for tools and services to be developed at EU level........................................................... 31
5.1. The requirement and opportunity to act at the EU level ............................................ 31
5.2. Identification of relevant options and recommendations ........................................... 32
5.3. Suggested roadmap for scenario selection and implementation .............................. 42
6. Further research needs .................................................................................................................. 45
6.1. Maps of irrigated areas .............................................................................................. 45
6.2. Evapotranspiration and abstraction monitoring ......................................................... 45
6.3. Governance ............................................................................................................... 46
References ............................................................................................................................................ 47
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Tables
Table 1: EO products suitability for the identified water managers’ needs, including
complementary applications ............................................................................................................ 17
Table 2: Overall characteristics of EO products for detecting non-authorised abstractions of types
1 and 2 .............................................................................................................................................. 19
Table 3: Overview of local data requirements, source of data and availability .................................. 28
Table 4: Opportunities and barriers to the use of Earth Observation for the detection of non-
authorised abstraction ..................................................................................................................... 30
Table 5: Overview of the scenarios for the development of EU products and services for the
detection and/or monitoring of non-authorised abstractions ........................................................... 32
Table 6: Summary of main characteristics of each scenario .............................................................. 38
Table 7: Overview of responsibilities for each scenario and step in procedure to detect non-
authorised abstraction ..................................................................................................................... 39
Table 8: Requirements for the development of Copernicus water abstraction tools and services ..... 41
Table 9: Roadmap towards implementation: overview. .............................................................. 43
Figures
Figure 1: Different temporal phenology patterns of wheat and corn both irrigated as it is
described by NDVI .............................................................................................................................. 9
Figure 2: Different NDVI magnitude patterns of irrigated and non-irrigated wheat ............................ 9
Figure 3: Different NDVI’s magnitude patterns of wheat with different levels of irrigation ............... 10
Figure 4: Example of annual map of irrigated areas in La-Mancha Oriental aquifer (Spain). Parcels
in yellow (red) indicate irrigation before 1984 (after 1984) ............................................................... 10
Figure 5: Overview of steps in using EO for detecting non-authorised abstractions.......................... 12
Figure 6: Overview of processing steps from crop water requirements (CWR) to water abstraction . 12
Figure 7: Overview of steps for the detection of non-authorised abstractions .................................. 14
Figure 8: Characteristics of water rights and suitability for the EO-based detection of non-
authorised abstractions .................................................................................................................... 22
Figure 9: Overview of demonstrative and operational EO tools and services. Asterisks indicate
methodology to obtain CWR ............................................................................................................ 23
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Glossary
Crop coefficient (Kc): the ratio of evapotranspiration observed for a given crop over that
observed for the calibrated reference crop under the same conditions
Crop phenology: study of the plants’ biological cycle throughout the year and its
seasonal and inter-annual response to climate variations, using different parameters
that describe the seasonal behaviour of the vegetation.
Crop water requirements (CWR): "amount of water required for compensating the
evapotranspiration loss from the cropped field" (Allen et al. 1998).
Earth observation (EO): collection of data and information about the Earth system using
remote sensing systems (mostly satellite-based, but also sensors on-board aircraft or
drones can be used).
Evapotranspiration (ET): transport of water from land surfaces into the atmosphere by
soil evaporation and plant transpiration.
Flow meter: an instrument for monitoring, measuring, or recording the rate of flow,
pressure, or discharge of water.
Ground truth: in-situ observations for the purpose of calibration and validation of EO-
derived parameters.
In-situ: refers to observations obtained through airborne sensors and ground based
installations.
Irrigation water requirements (IWR): crop water requirements minus effective (i.e.
usable for plant) precipitation.
Local data: all types of data (field measurements, databases, knowledge, and expertise
of local/regional crops and their phenology) acquired at local scale, i.e. for a
geographically-limited area.
Non-authorised abstractions: there are two types of non-authorised abstraction for
irrigation purposes. Both types can be either permanent or occurring during periods of
special restrictions (e.g. drought):
abstraction for irrigation in areas that do not have the necessary water
rights (non-authorised abstractions of the first type); and/or
irrigation water consumption beyond the legally allowed or assigned water
volume (non-authorised abstractions of the second type).
Normalized Differential Vegetation Index (NDVI): index that gives a measure of the
vegetative cover on the land surface. Dense vegetation shows up very strongly in the
imagery, and areas with little or no vegetation are also clearly identified.
Reflectance: the ratio of the intensity of reflected radiation to that of the radiation
incident on a surface.
Satellite image: digital image (e.g. of a land surface) obtained from a satellite-borne
sensor. EO sensors provide multispectral images covering several bands in the solar
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(and in some cases also thermal) spectrum.
Spatial resolution (of a satellite image): size of pixel corresponding to the size of the
surface area measured on the ground (depends on the sensor used and the satellite's
orbit).
Supplemental irrigation: ad-hoc irrigation depending on weather conditions.
Surface water balance (SWB): equation describing the flow of water through the Earth’s
surface.
Surface energy balance (SEB): flow of energy into and out of the Earth at the land
surface.
Water rights: authorisation to abstract water, characterised by a combination of criteria
related to:
water resources used: quantity and quality of the water, the source and
location;
characteristics of use: use, location and duration; and
administration of the right: ownership and transfer, security and
enforcement.
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1. Introduction
1.1. Context
Over-abstraction, or the abstraction of more water than is sustainably available, regularly triggers or
increases water deficits in the EU. It is currently considered the second most common pressure on the
ecological status of water bodies in the Union. The water restrictions or natural shortages it engenders
are a potential cause of conflicts between competing uses and could have substantial socio-economic
consequences.
In 2011, a quantitative target was set within the Roadmap for a Resource Efficient Europe1,
recommending a water abstraction level below 20% of the available renewable water resources. In the
2012 Blueprint to Safeguard Europe’s Water Resources2 document, the European Commission
reinforced its commitment for better water management, in accordance to the 3rd
Implementation
Report on the WFD3 that assessed the 2009 River Basin Management Plans and the 2012 policy
review of the Strategy on Water Scarcity and Droughts4. The Blueprint highlights the issue of non-
authorised water abstraction and recalls the responsibility of Member States on law enforcement. Non-
authorised abstraction consists in the abstraction of water without permits or beyond authorised
amounts, either over a year, or during a restricted period of time where the use of water is rationed.
Earth Observation (EO), in particular European Union’s Copernicus programme (ex-GMES5), was
indicated in the Blueprint to Safeguard Europe's Water Resources as a promising approach to
address quantitative issues related to water, through the detection of possible cases of non-authorised
abstraction and as a complement to the often limited field data available. Copernicus is composed of
three elements: (i) a space component with the development of the fleet of EU Sentinel satellites and
with an access to data from other satellites, (ii) a service component including atmosphere, land,
marine, emergency management, security and climate change services and (iii) an in situ component.
Several EO projects recently developed in the EU were co-funded in the framework of the Seventh
Framework Programme and linked to space-based applications research serving European society
(2007-2013) and the European Programme for the establishment of a European capacity for Earth
Observation, now known as “Copernicus”6. In 2014, new regulations were adopted, establishing a new
phase for the Programme which will feature new operational services by year 2020. The land
monitoring service addresses a broad range of environmental policies (water, biodiversity, nature,
soils, forest, waste…); a step by step approach was decided, starting with the multi-purpose products
at a global and European scale (such as the Pan-European land cover products CORINE Land Cover
and new High Resolution Land Cover layer). A local component providing detailed information on
targeted areas of interest will be progressively implemented including Urban Atlas, riparian areas
mapping and Natura 2000 sites monitoring. It might be extended to additional areas of interest and
1 http://ec.europa.eu/environment/resource_efficiency/pdf/com2011_571.pdf
2 http://ec.europa.eu/environment/water/blueprint/index_en.htm
3 http://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX:52012DC0670
4 http://ec.europa.eu/environment/water/quantity/pdf/non-paper.pdf
5 Global monitoring for environment and security services
6 www.copernicus.eu/
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further thematic services, taking into account users’ requirements and the outcomes of precursor
activities and studies such as this one.
1.2. Objectives
The purpose of this discussion paper is to assess the opportunity to develop a Copernicus service
dedicated to the management of abstractions for irrigation and provide a basis for the discussion on its
key technical specifications. It is aimed at the European Commission, in particular the DG ENV and
the DG ENTR, as well as the Research Executive Agency and the members of the Copernicus User
Forum.
1.3. Approach
This document is one of the outcomes of a study started in October 2013 and conducted on behalf of
the European Commission by BIO by Deloitte with Universidad de Castilla-La Mancha (UCLM)
(“Applying EO tools and services to detect non-authorised water abstractions”). Another deliverable is
the stakeholders Guidance document. Following the terms of the contract, it focuses mostly on non-
authorised abstractions in irrigation, although also exploring complementary applications based on
Earth observation in the field of water management. The document is based on UCLM’s long-standing
expertise in the use of EO for irrigation management (developed in many projects, e.g. SIRIUS
www.sirius-gmes.es), on lessons learnt from literature review, stakeholders’ interviews, case studies,
a series of four workshops7 and from the consultation of international EO experts and representatives
of water authorities. The list of consulted stakeholders, as well as further technical details and case
studies are available in the annexes to the Guidance document.
7 held in Spain jointly with Portugal, in Italy, in France, and in Greece.
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2. Opportunities from the use of EO
for the detection of non-authorised
water abstraction in the EU
2.1. Identified water managers’ needs for the detection and monitoring of
water abstractions
During workshops and interviews, stakeholders expressed their need for a better knowledge of water
abstractions and specifically on irrigation uses, irrigation infrastructures (channels, tanks), irrigated
areas and abstraction volumes. The operational needs emerged included different aspects:
continuous monitoring of irrigated areas and volumes abstracted from well-established
areas;
ensuring the reliability of self-declarations on water abstractions;
optimising field inspections to ensure compliance with legal requirements on water
abstraction;
ensuring compliance in regards to seasonal water restrictions in the event of drought
management.
Complementary needs included:
regularising historical water rights by means of a better identification of water users;
mapping of hydraulic works;
ex-post assessment on the implementation and efficiency of water management
systems, providing different time scales (crisis or structural) as a base for to adopting
future actions;
adjustment of water prices and implementation of a volume-based fee system;
support to irrigation scheduling to increase efficiency.
2.2. Potential of EO products for detecting and monitoring abstractions
The detection, of non-authorised abstractions requires:
all irrigated areas to have the necessary water rights clearly established (non-
authorised abstractions of the first kind); and/or
irrigation water consumption to remain within the legally allowed or assigned water
volume (non-authorised abstractions of the second kind).
Both kinds can be either permanent or limited to exceptional restriction periods of (e.g. in the event of
drought).
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In the first case, all irrigated areas need to be identified and cross-checked with all available
information/databases on irrigable areas (i.e. areas with a legal right to irrigate). Depending on
national and/or regional legislation, the legal right to irrigate may be linked to the land, an abstraction
point or a water source, either permanently or for limited periods of time (e.g. seasonal restrictions). In
the second case, irrigation water consumption should be monitored and cross-checked with regulated
allocation and/or hydrological planning data.
In either case, geospatial legal reference data (e.g. cadastral water rights, allocation to current
hydrological plan) is always needed. This also applies to any in-situ, non-EO-based approach. The
availability of legal reference data is a key condition for the detection of non-authorised abstractions
and is closely linked to the implementation of INSPIRE Directive and SEIS (Shared environmental
Information system) principles.
Earth observation (EO) can supply two key products to monitor abstractions and thus to support the
detection of non-authorised abstractions:
maps of irrigated areas (for non-authorised abstractions); and
maps of irrigation water consumption and abstracted volumes (second case).
For a detailed description of how these maps can be obtained see the following sections 2.2.1 and
2.2.2.
The detection of hydraulic works (channels, tanks) as sources of abstraction cannot be obtained with
High Resolution EO images, but requires orthophotography (airborne) or the employment of very-high
resolution satellites (<1m, like WV-2) (available at commercial image cost), implying a high cost and a
relevant resource intensity. This specific circumstance is not within the scope of this document, but
could be further investigated.
2.2.1 Potential of EO products for monitoring abstractions
The detection of irrigated areas (providing a clear identification of the exact location and areal extent)
requires land-use/land-cover maps that allow distinguishing irrigated from non-irrigated crops. A
successful and widely used methodology (also adopted and operationalized in the FP7 project
SIRIUS) implies the use of a supervised “multi-temporal classification” based on a time series of EO
images.
These images provide the temporal evolution of crops and vegetation during growing season through
spectral reflectances, derived Vegetation Indices, (like NDVI, the Normalized Difference Vegetation
Index, EVI, SAVI and others), and even, when available, surface temperatures. The classification
process based on temporal pattern recognition is based on the resulting differences of the canopy on
the above mentioned parameters that allow relating each pixel to a vegetation class. The classes need
to be defined on the basis of field work and previous knowledge of crop phenology in a given area.
The crop classification is the prerequisite for the identification of irrigated areas and the exact period of
irrigation.
The above mentioned process allows distinguishing:
different categories of crops (e.g. wheat from corn), as illustrated in Figure 1;
irrigated crops from non-irrigated crops within a same category of crops, , as illustrated
for wheat in Figure 2. This process also allows the detection of intermediate irrigation
magnitudes (e.g. high irrigation volumes vs. low irrigation volumes), as illustrated in
Figure 3.
The identification of plots that receive supplemental irrigation (i.e. less amount of water, but in a well-
selected timeframe) usually implies more difficulties: under this practice plots show lower contrast
compared to rainfed or irrigated plots of the same crop. Supplemental irrigation is usually used when
water stress occurs, and is employed both in extensive herbaceous annual crops and woody crops. In
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this case, precipitations data is needed to distinguish irrigation (the vegetation index, reflecting the
plant water status, does not differentiate between water coming from rainfall or irrigation). Where the
use of EO is not sufficient (e.g. woody crops with sparse ground cover, like vine or olive), in-situ
information like cartography based on very high resolution orthophotos can be used.
The whole procedure is not automatic. It requires a precise knowledge of crops and crop phenology,
and needs further corroboration by experienced operators. Figure 4 shows an example of an annual
map of irrigated areas (a comparison of the situation before and after the introduction of a new Water
Law in Spain).
Figure 1: Different temporal phenology patterns of wheat and corn both irrigated as it is
described by NDVI
Note: NDVI represents relative photosynthetic size of the canopy. These NDVI values can be converted to crop coefficient
values to estimate crop evapotranspiration.
Figure 2: Different NDVI magnitude patterns of irrigated and non-irrigated wheat
Note: Two parcels of wheat with the same sowing date and similar development at the beginning of the cycle (due to sufficient
amount of rainfall) exhibit a different behaviour in the dry months as a consequence of no irrigation in one of them (green dots).
CORN WHEAT
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Figure 3: Different NDVI’s magnitude patterns of wheat with different levels of irrigation
Note: Two parcels of wheat under different water supply: fully irrigated (red) and not well irrigated due a failure of pumping
(green). Sowing date is later in fall than in previous figure (leading to not enough rainfall during early phenology stage).
Figure 4: Example of annual map of irrigated areas in La-Mancha Oriental aquifer (Spain).
Parcels in yellow (red) indicate irrigation before 1984 (after 1984)
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2.2.2 Monitoring of abstracted volumes
The detection of non-authorised abstractions of the second type (volumes) requires mapping crop
water consumption over time during the growing season. This can be accomplished by using the same
time series of images used for the detection of irrigated areas, nonetheless requires further processing
(Figure 5 and Figure 6).
The basis of irrigation water requirements calculations is:
time series of reflectances and vegetation index (VI) maps can be converted into maps
of basal crop coefficient, the basic input for the widely used FAO56 model on crop
evapotranspiration calculations. The crop coefficient is analogous to a transpiration
coefficient. The FAO56 approach is the most widely used and operationally mature
method since the seventies to retrieve evapotranspiration from agricultural crops. The
crop coefficient can be obtained directly from linear relationships with vegetation indices
(Glenn et al. 2011) and/or from reflectance data and a series of intermediate
relationships involving fAPAR or LAI. The degree of accuracy of both methods is similar
(D’Urso et al. 2011), but as pointed out by Glenn et al. (2007) « it makes sense to use
VIs directly rather than convert them into LAI or fc estimates ». The VI-based basal crop
coefficient approach is operationally mature and can use spectral data from all sensors
at higher spatial resolution in order to obtain dense time series of images. The
upcoming Sentinel-2 constellation (providing suitable spectral imagery at 10 m of spatial
resolution and a revisit time of less than a week) could be a definitive tool in this
approach. Interpolation of consecutive images is used to fill the gaps (e.g. due to cloud
cover), and the product of basal crop coefficient and daily reference evapotranspiration
from the agro-meteorological station subsequently provides daily crop water
requirements on a pixel by pixel basis.
remote sensing of evapotranspiration can also be obtained from surface temperature
images by using additional techniques based on surface energy balance (Bastiaanssen
et al. 1998). Given that of all operational high-resolution satellites only Landsat currently
provides surface temperature (and with a revisit time of 16 days), and considering its
thermal channel spatial resolution of 100 m pixel size, this procedure is complementary
with the one previously described, and can provide an independent quality control in
suitable areas. The upcoming Sentinel-3 will also provide a thermal band, albeit at the
coarse pixel resolution of 1 km.
EO-driven soil water balance, according to FAO56, enables to calculate irrigation
water requirements on a pixel by pixel basis. Precipitation and soil hydraulic
characteristics are required. Following FAO56 procedures it is possible to calculate
irrigation water requirements under water stress situations, as is used either in
controlled deficit irrigation or in the case of supplemental irrigation. Knowledge of the
desired water stress degree is required, which needs local calibration. EO-based soil
moisture data can be useful in some cases, although its spatial resolution is only 250m
minimum pixel size (PROBA) or 500m (Sentinel-1).
the calculation of abstracted volumes require the efficiency figures of both irrigation
systems and irrigation distribution/storage.
Figure 5 and Figure 6 show the flux diagram of the whole process (including indications on the
sources of uncertainty and accuracy).
More sophisticated methods have been developed (e.g., D’Urso, 2005), going through a series of
intermediate physical parameters, like leaf area index (LAI). Comparative studies (D’Urso and Calera,
2006) show that the accuracy of these methods is similar to the direct NDVI approach.
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Figure 5: Overview of steps in using EO for detecting non-authorised abstractions.
Note: Crop Water Requirements (CRW) can be obtained either directly from visible and near-infrared (NIR) bands (left strand*)
or through the surface energy balance from additional thermal bands (right hand strand**).
The variation of water storage determine the irrigation requirements
Maps ofET/CWR* or ET/CWR**
Derived from the water balance. A simple approach (one layer model) is described in the FAO-56 manual.
Maps of Capillarity rise (estimated)
Maps ofRun-off (estimated)
Maps ofDeep percolation
Net irrigation water requirements
Maps ofPrecipitation
Precipitation data from
agrostations
Spatially distributedSoil Water Balance
I=ET+DP-Pp-RO-?S
Maps of variation in water storage in the soil
Water consumed at irrigation scheme
Water abstraction/Water demand
Uncertainties:-Precision of the LU/LC map-Efficiencies of the irrigation systems
Uncertainties:Efficiencies of the distribution/storage systems
Uncertainties:-Precision of soil maps(soil depth and hydraulic properties)-Knowledge of irrigation strategies (deficit irrigation?)
Figure 6: Overview of processing steps from crop water requirements (CWR) to water
abstraction
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2.3. EO applications for the monitoring of non-authorised water
abstractions
Where water rights are clearly defined and corresponding information is available, EO products
can support the detection of non-authorised abstractions by allowing:
The continuous monitoring of irrigated areas and abstracted volumes over large areas;
A better targeting of field inspections (the technology is recognised as able to provide
more objective sets of data compared to field inspection methods, and appears to be a
powerful decision making tool to direct and guide the detailed field inspection, e.g. by
providing targeted mission roadmaps for field technicians;) or even
Legal action in Member States, provided there is a legal recognition of EO as evidence:
the use of Earth Observation-derived data, considered as objective, can indeed provide
legal evidence in the event of legal conflicts. In a recent sentence (2012), the Spanish
Supreme Court validated remote sensing as a method for the recognition of water rights
and detection of illegal abstraction and for the identification of irrigated surfaces. The
Supreme Court decision established for the first time the requirements that this
methodology must meet in order to be considered as acceptable evidence in legal
proceedings: the provided service on the identification of irrigated areas must include
the presence in court of the individualised report about a plot, introduced by a senior
expert, who is responsible for its completion and quality.
The EU project Aperture (ENV4-CT97-437) investigated if and how high spatial resolution Earth
Observation (EO) data can be accurately and effectively used in judicial and extra-judicial proceedings
related to the implementation of environmental law. The main outcome of the legal investigations was
that there were no major constraints in the use of satellite images either in the court or in
administrative proceedings. The need for an expert who would explain technical matters in the court
cases was however strongly supported (Aperture Final Report, unpublished document, 2000), similarly
to the Spanish Supreme Court sentence.
A recent ESA study report states: "Broadly, the conclusion reached is that internationally there are no
major insurmountable barriers to the use of EO information by courts and administrative tribunals."
(European Space Agency, 2012). Purdy and Leung (2012) provide a summary of legal consideration
in the EU.
Figure 7 presents an overview of the steps leading to the detection of non-authorised abstractions
using EO images.
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Acquisition
of EO
images
Local ancillary
data (e.g. climate,
land use, water
balance)
Processing and development of maps
of irrigated areas and maps of water
consumption, incl. field validation
+
Estimation and mapping of water abstractions
Local ancillary data (e.g.
irrigation efficiency)
+
Comparison of legal reference data with EO-assisted estimates of abstractions
Verification on the field through targeted inspections Recognition of EO products as legal
evidence (e.g. in Spain)
Collection of legal reference data on water
rights
Detection of non-authorised abstractions
Identification of anomalies / suspicions of non-authorised abstractions
Figure 7: Overview of steps for the detection of non-authorised abstractions
EO products provide key information on water abstraction through the identification of irrigation
activities and the monitoring of abstracted volumes, both for routine and drought management.
However, like for in-situ non EO-based approaches, this information needs to be compared to legal
reference data to actually detect possible cases of non-authorised abstractions. Existence of water
rights and availability of corresponding information are a prerequisite for the detection of non-
authorised abstractions, irrespective of the method used to control abstractions.
2.4. Possible range of complementary applications
Due to the potential absence of prerequisites such as water rights, it is not always possible to detect
non-authorised abstractions in Member States (see Chapter 3). However, the EO products described
above allow for the development of a range of complementary applications that can meet some of the
water managers’ needs identified in section 2.1 and, more generally, contribute to the sustainable
management of abstractions and water resources in general.
In particular, EO maps can be used for the two following complementary applications:
where water rights are under a transition from historic to moderns management (e.g.
entry in force of new water regulations e.g. in Spain), EO products can help to detect
irrigated areas and regularise water rights. Similarly, maps of irrigated areas can
support the procedure of extinction of water rights after protracted non-use. Maps of
irrigated areas can be retrospectively obtained from satellite data for many years and
allow new assignments and a general review of water rights;
better understanding of irrigated areas, irrigation requirements and abstractions, in
order to better inform the development and/or revision of land and water management
plans;
ex-post assessment of the efficiency of water saving actions taken on the catchment at
different time scales (multi-annual, annual, monthly);
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implementation of a volume-based system of water fees and control of the accuracy of
self-declarations.
The detailed crop maps obtained with EO images can also be used to support the updating of
Copernicus land service products or the control of the implementation of CAP measures such as the
development of catch crops in France8.
More generally, maps of irrigated areas from satellite data can be shared and verified independently
by many stakeholders and thus provide tools for participation and conflict resolution.
The same EO maps could also be used to contribute to the following EEA indicators (source: Digest of
EEA indicators 2014, EEA Technical report 8/2014):
climate change indicators (growing season for agricultural crops, agrophenology, water-
limited crop productivity, irrigation water requirement);
water indicators (use of freshwater resources).
2.5. Discussion of the potential of EO applications
Earth Observation features a wider range of technical assets when compared to field observation
alone. EO can provide detailed maps of irrigated areas and monitor the level of water consumption in
large geographical areas (e.g. watershed scale) where field measurements provide point values of
evapotranspiration (ET) for a specific location, but fail in providing the ET on a regional scale. Images
can be obtained on a daily or weekly basis, depending on the resolution required. EO time series
provide basic products that can support and optimise field inspections by guiding it to selected areas.
Moreover, crop temporal pattern as recorded by EO products can be used as legal evidence in court (
with a recognised EO expert as a supporting testimony). Several comparative analyses show that
Earth Observation systems present a good accuracy compared to field measurement techniques of
crop water (Castaño et al., 2010; Cuesta et al., 2005) and water abstractions (Garrido-Rubio et al.,
2014). As an example, the application of SAMIR showed that the overall difference with field
measurements was only of 5% over 160 days. The average difference may however reach 18% of the
soil water balance at a weekly scale (Er-Raki et al., 2011). Current technical challenges (essentially
due to cloudiness and to the difficulties of differentiation of specific crop classes) can be solved with
more sophisticated approaches (e.g. interpolation of images, additional ground truthing, water balance
model) (see Chapter 3 on requirements).
EO provides estimates of water abstractions that are subject to uncertainties, and is not intended to
replace individual metering of abstraction points by means of flowmeters (although these may also be
subject to uncertainties).
The use of EO products is particularly valid to ensure the respect of routine water management
(controlling the compliance with standard water rights), where inspections can be carried out all along
the growing season. When an anomaly is identified on the EO maps, operators can rapidly verify the
conformity of abstractions directly on the field.
Under specific conditions, the use of EO products is also valid for drought management involving
seasonal water restrictions. Controlling the respect of these restrictions appears particularly
challenging, as they are generally applied on limited short periods of time, requiring great reactivity of
water managers to identify cases of non-compliance. EO can be a helpful tool in this respect as it can
8 Projet TETIS. Méthode d’évaluation par imagerie satellitaire des anomalies de cultures intermédiaires pour pièges à nitrate
(CIPAN) GEOSUD - DDT79. Presentation available at: www.cete-sud-
ouest.equipement.gouv.fr/IMG/pdf/06_DDT79_SatCIPAN.pdf
Use of Earth observation by water managers to detect and manage non-authorised water abstractions
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cover large areas, help target inspections and provide an opportunity to foster equity, easing
participation and transparency. The possibility to identify NDVI variations based on short term and
sometimes only partial water restrictions (vs. bans) has been questioned, but it is not a matter of
technical limitations in terms of time of EO images acquisition and processing (weekly images can be
available and, currently, the processing time from image acquisition to a final, ready for use product is
around two days on average, according to current Landsat8 production chain). The upcoming pair of
Sentinel-2 satellites are expected to provide at least a similar performance, at a higher spatial
resolution. The main possible shortcoming could rather be related to the magnitude and temporal
response of the canopy to small and short-term water restrictions. However, the identification of
irrigated areas from the time series of EO imagery is simplified in the event of drought, as a
consequence of lower rainfall usually implies water shortage in the root zone of crops, resulting in an
increase of the contrast between canopy of irrigated and non-irrigated crops, both spectrally and
temporally, as shown in Figure 2 and Figure 3. Therefore, images reliably explain the impact of
watering ban on vegetation development and thus enable a timely reaction to drive field inspection.
In the following cases, the use of time series of EO imagery for drought management has namely
been shown to be reliable (e.g., Calera et al., 2013):
irrigation was not allowed in sensible areas where the impact of abstraction could have
put at risk the ecosystem survival (river running dry along the path in which the river
loses water by infiltration).
reduction of abstraction were possible by decreasing the allowable amount of water per
unit of area for each water management unit (farm or group of farms with the same
source of water). A first estimate was based on the determination of the irrigated area in
each management unit. Monitoring showed that shifting irrigated crops from summer to
spring was a very effective measure to decrease abstraction.
Extensive assessments of costs of field measurements approaches alone and compared to their
combination with Earth Observation-derived information were carried out within the FP7 SIRIUS
project for pilot areas in Spain, Italy, Turkey, and Brazil. They showed that the cost of Earth
Observation services could be significantly lower than the cost of field measurement and inspection
alone. Water users associations have already demonstrated their willingness to pay for such services.
Use of Earth observation by water managers to detect and manage non-authorised water abstractions
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In summary, the use of Earth Observation-derived data to monitor water abstraction is a mature
system, and several service providers with demonstrated operational capacity have shown to be
ready to implement it. The new coming Sentinel data generation will provide new opportunities to
improve this system, in particular with Sentinel 2 (10m resolution) and possibly by taking advantage of
Sentinel 3 (thermal band at 1 km pixel resolution) or Sentinel-1 (soil moisture) data
The key benefits of EO-based monitoring of abstractions include:
large geographical coverage at adequate spatial and temporal resolution;
good demonstrated accuracy;
vastly increased efficiency of surveillance and inspection;
objective assessment tool and trusted by water users as such;
vastly reduced monitoring cost and needs for human resources;
acceptance by users and demonstrated high interest of representatives of water authorities.
additional benefits coming from the development of additional land-use and climate-relevant
datasets;
However, there is still little knowledge about its practical use, assets and shortcomings for the
detection and management of non-authorised water abstractions in specific situations beyond the
experiences of SIRIUS and a few other initiatives. The key barrier to the detection of non-
authorised abstractions, irrespective of the method used (in situ or EO), remains the existence of
defined water rights and the availability of corresponding spatially explicit information. Where
water rights are not defined, however, EO products can be used for a range of intermediary
applications meeting identified needs of water managers.
Table 1 highlights EO products suitability for the identified water managers’ needs.
Table 1: EO products suitability for the identified water managers’ needs, including
complementary applications
Identified needs of
water managers
EO
suitability
EO potential and assets Shortcomings and barriers
Ensuring the reliability
of self-declaration of
water abstractions
High EO enables full area
coverage to detect
“suspicious” parcels
Difficulty to clearly differentiate perennial crops (need for additional in-situ data)
Technicians may need training
Optimisation of
inspections
(abstractions control)
Implementation of
volume-based fees
and reliability of self-
declarations
High
EO enables full area
coverage to detect
“suspicious” parcels and
direct field inspections
there
Difficulty to clearly differentiate
perennial crops (needs additional in-
situ data)
Technicians may need training
Dependent upon the existence and
availability of legal reference data
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Identified needs of
water managers
EO
suitability
EO potential and assets Shortcomings and barriers
Respect of restrictions
for drought
management
Medium EO enables full area
coverage to detect
“suspicious” parcels
Difficulties to detect partial and short-
term restrictions in perennial crops
(needs additional in-situ data and/or
higher resolution EO time series)
Requires reactivity in the processing of
information and procedures in place to
handle on-demand requests by
organisations in charge of managing
water restrictions
Technicians may need training
Dependent upon the timescale and
nature of restriction measures
Monitoring of irrigated
areas and abstracted
volumes for a better
water management
High
Large area coverage at
adequate spatial and
temporal resolution
Users in many areas not yet prepared
(technically, expertise, administrative
structures)
Regularisation of
historical water rights
(e.g. Spain)
High EO provides the only
means to document
irrigated parcels in past
years (back to 1972)
Recognition as legal evidence achieved
e.g. in Spain, but not in most other MS
Mapping of hydraulic
works
Low
Ex-post assessment of
the efficiency of
actions taken, at
different time scales
High EO-based indices (water
abstraction vs planning;
irrigated vs irrigable)
enable full area
coverage at adequate
resolution
Users training and uptake needed
Adjusting water price
and implement
volume-based fees
High Based on estimation of
abstracted volumes
Users training and uptake needed
Irrigation scheduling High Near-real-time large
area coverage at
adequate spatial
resolution
Users training and uptake needed
Use of Earth observation by water managers to detect and manage non-authorised water abstractions
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3. Requirements for the detection of
non-authorised abstractions and
complementary applications
3.1. Technical requirements for the monitoring of water abstractions
Table 2 highlights the technical requirements for the implementation of an operational EO-based
system for the monitoring of abstractions (identification of irrigated areas and mapping of abstracted
volumes). It also presents associated advantages and shortcomings in terms of accuracy, costs and
applicability.
Table 2: Overall characteristics of EO products for detecting non-authorised abstractions of
types 1 and 2
Requirements Type 1
Mapping irrigated areas
Type 2
Mapping water consumption
Crop water requirements Irrigation water
requirements
Irrigation water
abstraction
Basic EO data
requirements
See box below
Time series of satellite images in visible and near-infrared (NIR) spectrum range (thermal
range optional)
EO
satellite/sensor
Sensor
resolution
Resolvable
parcel size
Image cost Comments
Landsat-8 30 m
1 ha free standard
processing
Landsat-8-
thermal
120m 15 ha free surface energy
balance (SEB)
Landsat-8 type
(Spot, IRS, DMC)
20-30 m 1 ha 1,000-5,000
€ per
100x100 km2
standard
processing
Sentinel-2 10 m 0.1 ha free planned 2015
Sentinel-3
(thermal)
1 km 10 km2 free SEB
commercial very-
high-resolution
around 1 m 0.03 ha 1,000-5,000
€ per 10x10
km2
increases
processing effort
(many small
images)
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Requirements Type 1
Mapping irrigated areas
Type 2
Mapping water consumption
Crop water requirements Irrigation water
requirements
Irrigation water
abstraction
Required EO image
frequency and
period
every 2-4 weeks during
growing season
every 1-2 weeks during growing season
Additional data
requirements
ground truth visits to a
small sample of fields
agro-met station
Ground truth
precipitation;
soil water
storage
irrigation
system
efficiency
local information about main crops phenology and development (for initial methodological validation in a new area and later to improve accuracy of both types)
existing land use/land cover maps (useful basis to start with, but not necessary
orthophotos or EO very high spatial resolution (useful for woody crops)
Required models none (FAO-56)
(Allen et al., 1998)
soil water
balance,
FAO56
none
Uncertainties (depend on ground
truth sampling)
soil evaporation* soil
parameters
system
heterogeneity
Accuracy
92% identified correctly
(Calera et al., 2013)
+-5-10% uncertainty for
herbaceous crops
Comparable with eddy
covariance uncertainty &
FAO56 based on field
work
(Glenn et al., 2011;
Tasumi and Allen, 2007)
10-20%
(Campos et al.,
2010; Glenn et
al., 2011;
Melton et al.,
2012b)
10-20%
(Garrido-Rubio
et al., 2014)
Cost** 1-3 €/km2/year 2-4 €/km
2/year ***
(implementation and maintenance of ground truth not included)
Limitations/barriers very small parcels
low contrast between irrigated and non-irrigated crops
woody crops with management under water stress, supplemental Irrigation
very frequent full cloud cover that can limit the number of exploitable images (in particular in Northern-Western EU).
Overcoming barriers SENTINEL2 (10 m pixel size) as the basis of constellation to obtain dense time series. Use of very high spatial resolution, as RapidEye, Quickbird, Ikonos, Pleiades, WorldView, etc.
Multiannual monitoring; dry years increase contrast between irrigated and non-irrigated crops.
Management of
drought and crisis
The designed system enables enforcement of Annual Exploitation Plan
Weekly monitoring enables to detect non authorised irrigation
Legend:
CWR=crop water requirements; IWR=irrigation water requirements; IWA=Irrigation Water Applied
* in crops that do not cover the soil completely, e.g. vineyards, olive and orchard trees
** Source: large-scale production line cost estimation in context of FP7 project SIRIUS
*** Cost depending on available local information: cadastre, maps of hydraulic properties of soil, (agro)meteorological stations
network, ground truth.
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Time and spatial resolution requirements for EO images
The detection of non-authorised abstractions of the first type (irrigated areas) requires land-use/land-
cover maps that allow for a distinction of irrigated crops. This is accomplished by multi-temporal
classification on the basis of a time series of EO images (for details of this processing, see the next
section). It is not possible to rely exclusively on existing land use maps (e.g. cadastral, CORINE Land
Cover) as they may not be updated and may be based on classes that do not take into account
irrigated vs. non-irrigated areas. The time resolution required by water managers and commissaries
for this purpose is to have a fairly cloud-free image (<10% cloud) every 2-4 weeks from about 2 weeks
before the start of the growing season until its end.
The detection of non-authorised abstractions of the second type (abstracted volumes) requires
mapping crop water consumption over time during the growing season. This is accomplished by using
the same time series of images as above in type 1, but with further processing (Figure 1 and Figure 2).
The time resolution requirement for this purpose is slightly different from type 1 mentioned above in
that one fairly cloud-free image is needed every 1-2 weeks, again from shortly before the beginning of
the growing season until its end.
For both types, obtaining images covering at least 90% of the area is normally sufficient.
The required time resolution for both purposes can best be achieved on the basis of a multi-sensor
constellation, integrating data from all available EO platforms. The corresponding inter-sensor cross-
calibration algorithms have been developed (Martínez-Beltrán et al., 2009) and a comprehensive
cross-calibration database has since been established.
The required spatial resolution for both types depends on the parcel size statistics in the area. Yet, the
current Landsat-8 type satellites can be used in most areas. This takes into account the need to
always aggregate 3x3 sensor pixels (compensating for geo-referencing uncertainties) in order to
obtain a stably geo-localised time series (i.e. making sure that the same pixel is in the same place in
all image-based maps) (Martínez-Beltrán et al., 2009). With the advent of Sentinel-2 (expected to
deliver operationally in 2015) parcels from 0.1 ha size can be resolved. In areas with particularly small
parcels, commercial satellites offer higher resolution, albeit at higher image and processing cost.
Sensors on-board low flying aircraft, ultralights, or drones accomplish the same, while offering more
local flexibility at high cost. The combination of various sensors and various data sources (i.e. the full
use of the multi-sensor constellation mentioned above) is essential for better efficiency of such tool.
3.2. Legal and administrative requirements for the detection of non-
authorised abstractions
As highlighted in Chapter 2, the definition and availability of spatially explicit information on water
rights (irrigable areas, abstraction allowances) against which to compare the EO-assisted products
(maps of irrigated areas and abstracted water volumes) is a prerequisite for the detection of non-
authorised abstractions. This is true irrespective of the method used (in-situ or EO-based). Depending
on their existence, status of implementation and nature, water rights are more or less suitable to the
detection of non-authorised abstractions, as illustrated in Figure 8. These water rights requirements
are sufficient to compare with EO products and better target field inspections.
Furthermore, optional requirements are the recognition of EO-based evidence in administrative and
legal procedures (e.g. sanctioning in case of abstraction beyond authorised volumes or outside
authorised periods, formal recognition of water rights from earlier legal situations) and the anchoring of
EO-based monitoring and control in national policies.
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Figure 8: Characteristics of water rights and suitability for the EO-based detection of non-
authorised abstractions
3.3. Operational requirements
The required infrastructure and expertise for using the service requires very little infrastructure
and expertise: a standard PC or laptop and some training of the user is usually sufficient. Users are
not required to have any technical or informatics background.
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4. Current challenges at MS level
In light of the requirements to develop EO-based tools and services for the detection of non-authorised
abstractions, MS are likely to encounter several challenges, as identified in previous projects and
through the interviews, case studies and series of workshops.
4.1. EO technical capacity
Following the discussion on requirements from chapter 3, MS would need dense time series of high
resolution imagery covering the entire crop growing season, and more specifically bi-weekly EO
images from a high-resolution (HR) Virtual Constellation (multi-sensor time series at 10-30m
resolution). These can be acquired with satellites like Landsat8 and DeIMOS, which are currently
available. A significant step forward in simplifying operations is expected from Sentinel-2, to be
launched later in 2014, which will be able to “see” spatial scales from 0.1ha. In areas where smaller
spatial scales prevail, RapidEye (5m by 5m) provides a high-quality reliable solution.
Beyond the availability of EO images, the challenge that could be encountered by MS rather lies in the
operation of EO-based monitoring. So far, EO-assisted abstractions monitoring has been introduced
only in two MS (Spain and Italy), at regional and/or local level. In contrast, EO has been used for
general water management in several MS, either at (pre)operational or test/demonstration level
(Figure 9). As the EO and supporting data needed for both purposes are the same, the step from
water management application to the focus on abstractions monitoring is quite straightforward
technically. It implies, however, more information, as well as appropriate legal and administrative
structures to be in place.
Figure 9: Overview of demonstrative and operational EO tools and services. Asterisks indicate
methodology to obtain CWR
There are tools and services for similar applications (agricultural sector, farm advisory, drought
monitoring, land-use) available in several MS, which partly require and use the same basic data.
These synergies can be explored.
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4.1.1 Services or applications for water management
MINARET (MonitorINg irrigated AgriculturRe ET) has been developed by the Regional Government of
Andalucía and the Spanish Research Council Córdoba as a planning and operational tool for routinely
monitoring crop water consumption in the irrigated lands of the Guadalquivir basin (Southern Spain). It
has been made available to the corresponding river basin authority for use in their operations. Like
SIRIUS, it is based on the Kc-VI approach (González-Dugo et al. 2013).
The Dutch company WaterWatch has offered products and services to monitor crop water
consumption for over 15 years and has carried out relevant studies in many African countries as well
as in Saudi Arabia and Yemen. Their approach is based on the SEBAL algorithm (developed by
Bastiaanssen et al. 1998), which estimates the components of the surface energy balance (SEB) from
Earth Observation data. It requires Earth Observation image data both in the solar and thermal
spectral range. The latter limits the achievable spatial resolution (e.g. Landsat solar channels at 30m
resolution, thermal at 120m, which means that only parcels larger than 15 ha can be resolved, in
contrast to 1 ha for solar channels).
The University of Idaho Department of Water Resources has further developed SEBAL into
METRIC (using a simplified calibration approach). Their initial services to monitor crop water
consumption and irrigation water abstractions for nearby water users associations have been
extended to other areas across the U.S. (Allen et al. 2007).
4.1.2 Services or applications for irrigation advisory (or irrigation scheduling)
They are also based on the mapping of crop water requirements. Many of the Earth Observation-
based irrigation advisory services also offer crop inventories, which provide the necessary information
for detecting irrigated areas. Of the nine examples provided in Figure 9, five are fully operational
(TOPS-SIMS, IrrisatSMS, IRRISAT, SIRIUS-IFAS, FieldLook), while the others have been applied and
demonstrated in individual cases.
TOPS-SIMS is a fully operational prototype for mapping crop water requirements (centred on irrigation
advisory), but also allows for monitoring crop water consumption (Melton et el. 2012).
The SIRIUS Integrated Farm Advisory Service has been established in the Spanish La Mancha
area. It offers irrigation scheduling as well as advice on fertilization and yield forecast (Calera et al.
2013a).
FieldLook has been developed by WaterWatch (now under the roof of eLEAF) and is based on
SEBAL (requiring thermal imagery).
The Italian IRRISAT service has been providing irrigation scheduling to large areas in the Campania
region (Vuolo et al. 2013).
IrrisatSMS (currently discontinued) offered irrigation advisory by SMS to farmers in Australia and
California (Hornbuckle et al. 2009a).
Use of Earth observation by water managers to detect and manage non-authorised water abstractions
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IrriSATSMS
The IrriSATSMS system combines satellite images data, meteorological data and location
coordinates to determine how much water crops have used and how long farmers need to run their
irrigation system each day.
IrriSATSMS uses satellite images derived from Landsat 5. These satellite images are collected
across Australia every 14-20 days.
Daily, customised, irrigation water management information is then sent out to irrigators by SMS
messaging. The service sends actual pump run times based on your individual irrigation
application rates, there by simplifying irrigation decisions.
IrriSATSMS (currently discontinued) was used to9:
manage and benchmark water use efficiency across 26 000 ha of irrigated cotton (in
2010/2011)
help 175 peri-urban irrigators in the Hawkesbury -Nepean Catchment
assist winegrape growers in the Murrumbidgee and Murray Valleys manage 60 000
megalitres of high security irrigation water for vineyard irrigation
SAMIR is a tool for estimating agricultural water requirements based on the Kc-VI approach,
combined with a distributed soil water balance model. It has been integrated with a range of models in
a decision-support system for irrigation water monitoring and management for use by the Tensift river
basin authority (Morocco) (Er-Raki et al., 2011).
AGRASER is a very complete system of farm advisory and has also been extensively used by
Mexican insurance companies.
Isareg and GISAREG have been developed by the University of Lisboa and applied in Portugal as
well as in Latin America.
TELERIEG has investigated irrigation advisory with a special focus on woody crops (e.g. citrus trees),
also using very-high resolution imagery from airborne sensors.
9 CSIRO website : www.csiro.au/Organisation-Structure/Flagships/Sustainable-Agriculture-Flagship/Irrisat-Project/Using-
IrriSATSMS.aspx
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TELERIEG PROJECT
The main objective of the TELERIEG project was to develop knowledge and tools on the
application of remote sensing and geographic information systems for the improvement of
irrigation water management and the response to natural risks affecting agriculture in the
Southwest Europe (Erena et Lόpez Francos, 2012).
The final results were an automated image processing system that generates daily maps with
useful parameter for irrigation management, and a geoportal gathering agro-climatic and
cartographic information, adapted to the INSPIRE Directive (Berthoumieu, 2012).
Concerning the application of remote sensing for the improvement of water management, three
different spatial resolutions for Earth Observation have been investigated:
Observation from a short distance or above canopy with a near infrared and visible
camera coupled with a thermal camera (10cm pixels) for irrigation scheduling in
vineyards (Bellvert and Girona, 2012), irrigation management of citrus trees
(Jiménez-Bello et al., 2012)
Observation with cameras installed on small aircrafts or satellite with high resolution
as SPOT, DMC (10cm to few meters pixels) for the estimation of actual
evapotranspiration (García Galiano and García Cárdenas, 2012)
Observation with satellites with a lower resolution as Landsat 5 (120 m) and 7 (60
m), HJ (China), NOAA, MODIS (240m for visible and 960 m for thermal) (50m to a
km pixel)
Using airborne platforms enables to get a high spatial resolution. However, this system has a cost
of about 150 000 to 200 000 € for the equipment plus about 150 €/h for the flight (or a bit less
depending on the aircraft cruise speed) (Berthoumieu, 2012).
4.1.3 Services or applications to support precision farming
The advent of Earth Observation via satellite systems has enabled the development of crop monitoring
systems and precision farming tools which are substantial assets for modern agriculture.
Satellite images enable providing information on current field and crop conditions that are essential for
agricultural management such as the NDVI index, the nitrogen deficit, soil moisture, weather forecast,
for a specific location. Several commercial companies offer crop monitoring tools that inform farmers
about their crops conditions and provide management advices at key stages of crop growth. These
tools are real decision support systems for farm management and help farmers to plan and carry out
agricultural operations. Remote management of crops makes it possible to target problematic areas
early in advance and react fast, thereby reducing the need for soil sample collection and analysis and
consequent late interventions10
.
These services or applications to support precision farming generally focus on input management, but
not necessarily on irrigation management. Consequently, they often do not provide maps of crop water
requirements (i.e. the information necessary for detecting non-authorized abstractions of the second
kind), neither do they provide maps of irrigated areas (i.e. the information required for the detection of
non-authorised abstractions of the first kind). However, they are based on Earth Observation images
which can be used to derive the information required to detect non-authorised abstractions. In
10
http://centres.insead.edu/social-innovation/what-we-do/documents/Farmstar.pdf
Use of Earth observation by water managers to detect and manage non-authorised water abstractions
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addition, they normally also either provide or have access to the local data needed to calculate crop
water consumption. Scale might be another issue here, as precision farming services often focus on
smaller areas, albeit at higher resolution.
Most relevant examples include Farmstar (used in France, Germany, Australia, Canada and South
Africa11
), Cropio12
(North America, Europe and CIS), FarmSat13
(France, USA and Australia),
FieldLook (Netherlands, Poland, Ukraine, Canada) and AgroSat (Spain).
FARMSTAR
Farmstar is a precision agriculture technology, developed by EADS-Astrium since 1996 and
operational in France since 2002.Since 2006, EADS-Astrium and Arvalis work together to develop
and commercialise Farmstar.
Astrium Services have access to a large satellite imagery and aerial data catalogue: SPOT satellite
family, Pleiades, TerraSAR-X, TanDEM-X, FORMOSAT-2 and DEIMOS14
. They operate satellite
and aircraft themselves and have thus full control over data acquisition.
Satellite data are combined with agronomic models that incorporate weather data and plot
characteristics informed by farmers (location, crop variety, date of sowing depth and type of soil,
type of irrigation system). Prescription maps are then generated and sent to farmers within 5
days15
.
Subscribing to the Farmstar service cost on average 10 € per hectare.
However, if Farmstar was implemented with a great success in France (250,000 ha in 2006)16
,
trials in the UK experienced problems. The main explanation is that unlike in France, farmers
cooperatives in the UK are fewer and work differently. British farmers seem to be more suspicious
concerning the productivity of ‘new-fangled’ technologies. Also, the weather and clouds presence
make clear satellite images more difficult.
In conclusion, “dual use” of irrigation advisory initiatives for detection of non-authorised abstractions
would involve additional steps of image processing and product generation (calculation of ET); the
derivation of maps of irrigated areas (from a time series of images); and possibly a mosaicking of
smaller images into a larger area.
4.2. Governance and political commitment
Water management happens in a complex web of institutions and other actors, at a range of
interacting spatial and temporal scales and over a range of equally interconnected governance and
policy levels (farm, local/regional, MS, EU). The acceptance of Earth Observation-derived information
for the monitoring of non-authorised abstractions seems to depend on local awareness of the issue
and political commitment to secure compliance with water rights, as well as on the support of
associations accompanying water users for such technologies and on the history of the use of Earth
Observation services for other purposes. The major difference in governance structure is introduced
by the water source. In areas irrigated from groundwater, we often find large numbers of individual
11
www.spectralcameras.com/files/Applications/precision-farming_farmstar.pdf 12
https://cropio.com/media/cropio_en.pdf 13
www.farmsatpro.geosys-na.com/Portal/Public/LoginGeosys.aspx?ReturnUrl=/portal/default.aspx 14
Astrium website : http://www.astrium-geo.com/en/209-our-activity 15
centres.insead.edu/social-innovation/what-we-do/documents/Farmstar.pdf 16
www.spectralcameras.com/files/Applications/precision-farming_farmstar.pdf
Use of Earth observation by water managers to detect and manage non-authorised water abstractions
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private farm holdings, sometimes (e.g. in Spain) grouped into an Irrigation Community. Areas mainly
irrigated from surface water are normally governed by Water User Associations (which are also in
charge of the land reclamation and channel networks). The monitoring and control of abstractions
(areas and volumes) are easier in surface water areas, where technical and social monitoring and
control mechanisms are normally in place already. Examples in Spain for instance show that
groundwater aquifers governed by an Irrigation Community can manage the abstractions of their
members quite well.
4.3. Definition of water rights and availability of corresponding
information
The common denominator to any approach for the detection of non-authorised water abstractions is
the availability of legal data regarding water rights. Where water rights are defined, data is mostly
available at the user level. Legal data on water rights are available in some MS, but not everywhere.
This means that there is not always the required legal reference data available against which to
contrast the EO-based monitoring data (see Annex 5 to the Guidance document about the availability
of water rights in the different countries).The compilation of water rights in a given area may therefore
require a combined top-down / bottom-up approach.
4.4. Local data availability
Table 3 provides an overview of the local data requirements and current knowledge about existing
sources and availability.
Table 3: Overview of local data requirements, source of data and availability
Datasets Details Sources Sources and data availability
Meteorological
data
Daily agro-
meteorological
data and rain
gauge data for
the calculation of
crop water
consumption
(agro)meteorological
station networks from
MS or WMO (World
Meteorological
Organisation) (in-situ
data)
Alternative options:
Meteorological satellites
(e.g., Meteosat Second
Generation) – data
products provided by
LSA SAF17
or numerical
weather prediction model
output data
Available in all MS
Potential synergies with the
Copernicus in situ coordination –
agreements foreseen with
Eumetnet
Soil maps of
water retention
Currently available pan-European
products or MS soil data
17
Land Surface Analysis Satellite Applications Facility; landsaf.meteo.pt
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Datasets Details Sources Sources and data availability
capacity facilitated by the European Soil
Portal hosted by JRC18
Local information
about main crops
phenology and
development
FAO database can be
used as basic
reference19
National databases
Currently available in some MS
and some areas
Abstraction
monitoring data
Flow meter (in-
situ) data in
selected locations
for calibration and
continuous
ground truthing of
crop water
consumption
Monitoring networks Available in some MS, for
pressurised systems Not
available for flood irrigation
systems (like in the South of
France)
Existing land
use/land cover
maps (optional)
CORINE Land Cover20
;
Copernicus new High
Resolution layers (1 ha
resolution) and 'local'
component products
(Riparian areas
mapping)
LPIS (for parcel
delineation and land
cover/land use)21
Available in all MS for 2006.
Currently being produced for
2012 data.
Access and availability conditions
vary widely across MS.
4.5. Economic aspects
Based on currently active services, the cost of implementing and running such a service has been
estimated at the order of 1-3 €/km2/year. This cost estimate is based on long-term precursor services
implemented in Spain and Italy as well as on the outcome of the FP7 project SIRIUS, where a fully
operational production line was developed and implemented in 8 countries on 4 continents.
According to the views expressed by workshop participants (users), the cost for abstractions
monitoring and control (as mandated by EU and national policy) should be assumed by the EU and
each MS administration. In contrast, if the service is intended to provide water management and
irrigation scheduling support (which helps farmers improving their business profit) then users have
expressed readiness to pay for it.
In the example of Junta Central de Regantes La Mancha Oriental (where an EO-assisted water
management and abstractions control service has been running for over 15 years), the annual service
cost has been shared equally between users, River-basin authority, and Regional Government.
18
Eurosoils.jrc.es.europa.eu 19
http://www.fao.org/nr/climpag/aw_3_en.asp 20
http://land.copernicus.eu/pan-european/corine-land-cover 21
http://ies.jrc.ec.europa.eu/our-activities/support-for-member-states/lpis-iacs.html
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4.6. Summary
Table 4 summarises the key factors in the implementation of an EO-assisted system or service for the
monitoring and control of non-authorised abstractions, keeping in mind that their importance may vary
depending on the local contexts.
Table 4: Opportunities and barriers to the use of Earth Observation for the detection of non-
authorised abstraction
Opportunities Barriers Variable factors
Technical Large geographical coverage
Good accuracy in identification of irrigated areas and mapping of abstracted volumes
Reliance on cloud conditions
Difficulty to identify small cultivated parcels
Calculation of abstracted volumes for some crop types require special ground truth calibration
Need for Earth Observation capabilities
Multi-sensor constellation.
Future Sentinel-2
Information on water rights and land uses
Economic Reduced costs and needs for human resources
Investments: costs of data / cost of human resources
Average cost of service: 1-3 €/km
2/year
Existing capabilities at water management authority (GIS, image processing)
Private providers to outsource the entire service or parts of it (image processing, webGIS)
Societal Acceptance and high interest demonstrated by representatives of water authorities
Participatory tool that facilitates collaboration between all stakeholders, transparency, conflict resolution
Little knowledge of the use of such technologies for the detection and management of non-authorised water abstractions.
Local challenges related to water
Support of key water users associations
Administrative
and legal
Efficiency of surveillance and inspection
Objective assessment
Consideration as legal evidence in at least one MS (Spain)
No water rights OR water rights based on flows OR based on volumes allocated to abstraction sources
Absence of information on water rights and detailed land uses (issue shared with other approaches for the detection of non-authorised abstractions)
Still little consideration as legal evidence
Political commitment to secure compliance with water rights
Governance in areas irrigated with groundwater (very large number of individual abstraction points) is often more difficult than with surface water (network of channels and abstraction points managed by users association)
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5. Options for tools and services to
be developed at EU level
5.1. The requirement and opportunity to act at the EU level
The requirement to monitor and control water abstractions has been defined in the Water Framework
Directive (WFD). Over-abstraction of water is also highlighted in the Blueprint to Safeguard Europe’s
Water Resources as a significant pressure impeding the achievement of Water Framework Directive’s
(WFD) good status objectives. At present it is mostly the Southern MS that are affected by the issue at
stake. However, several South-Eastern and Eastern MS have expressed their concern that non-
authorised abstractions may be a dormant issue which will soon become important to deal with and to
be prepared for. Non-authorised abstractions, which remain out of record, may play a substantial role
in over-abstraction22
. Therefore, the detection of non-authorised abstractions provides a crucial
opportunity for improving water balances across the EU and helps achieve WFD objectives.
However, despite substantial progress in water management throughout the EU and some EO pilot
cases, most MS dealing with the issue of non-authorised abstractions consider they still lack tools and
resources that enable them to detect and manage these unsustainable practices.
The Blueprint clearly indicates Earth Observation (EO) - in particular the EU’s Global Monitoring for
Environment and Security (GMES, recently renamed Copernicus) - as a promising tool and instrument
for the detection of non-authorised abstractions. The Blueprint Impact assessment (SWD/2012 382
final) assessed this recommendation by analysing policy options for metering (as the necessary action
for the volumetric measurement of water use, and, therefore, as a necessary basis for an effective
pricing policy). Option 2a, which consists in “Mapping all EU large irrigated areas via the GMES
initiative and matching these areas with water abstraction permits to help Member States enforce
them and tackle illegal abstractions”, is one of the four options initially considered to promote
metering. The Blueprint Impact assessment states that implementing Option 2a on Copernicus would
enhance water governance at the river basin and local level and is expected to be more effective and
efficient than in situ-based inspections alone. The document deems appropriate for the Blueprint “to
refer to the possibility for the Commission to foster metering take up through the enforcement of article
9 of the WFD and through the enhanced use of Copernicus mapping to support Member States in
monitoring water abstraction at catchment level.”(p.48)
The Blueprint impact assessment also reminds that 60% of EU river basins are international, shared
by two or more countries, and that action taken by a single or a few MS is not sufficient to sustainably
tackle quantitative aspects of water management across national boundaries.
Furthermore, monitoring of abstractions is a pre-condition for the proper implementation of pricing
policies in water stressed areas (WFD Art. 9). In order to be effective in cross-border basins and to
22
Which can also be due to over-allocation of water to users in a river basin, e.g. due to an overestimation of the available amounts, or to economic or political pressure.
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prevent negative effects on the internal market, economic incentives to use water at its true cost for
society should be applied in a consistent fashion in the EU. Therefore, also the metering principles,
tools and instruments should be consistent across all MS.
Yet, the need to act at EU level is triggered not only by the need to ensure consistency of water
allocation mechanisms in transboundary basins and a level playing field in the implementation of the
WFD, but also by the economies of scale and quality improvements that can be achieved by common
methodologies and datasets.
Most MS already confronted with water scarcity have shown high interest in the development of EO-
based water abstraction monitoring to complement more conventional approaches, such as the
reliance on flow meters. However, the implementation of EO-based tools and services has, so far, be
confined to isolated experiences as MS often lack expertise and the necessary enabling environment
to develop EO products for this purpose. A better knowledge of abstractions in general would support
the overall water management, and the same EO tools and services used for the detection of non-
authorised abstractions actually support a range of intermediary applications. One of them could be
the possibility to feed the EEA water-related set of indicators and thus help refine EU trends regarding
water uses and water balances.
The production of the basic map of irrigated areas and of the map of water irrigation requirements are
based on the same EO images for all EU countries, which highlights the opportunity to optimise efforts
to produce pan-European standard tools, and possibly services, to be used as such, or further
processed, within MS. Furthermore, for a system based on global data, as is the case with EO
images, cross-border interoperability is an important consideration, and adherence to and compliance
with the INSPIRE framework will also pave the way for a pan-European approach. This principle has
for instance been applied to a prototype (SIRIUS) from the first design of its services to their
implementation in 8 countries on 4 continents.
Copernicus has been conceived as a European monitoring system, in support of European policies as
well as of European platforms and sensors. Abstractions monitoring will provide a clear case of an
application that fills Copernicus with “life on the ground”, in true connection with and support of the
users that most need it (water managers at all levels, from farm to aquifer, irrigation scheme, river-
basin, and MS government), as well as in support of and supported by EU private sector capacities.
5.2. Identification of relevant options and recommendations
This section gives an overview of the different options (scenarios) for the development of Copernicus
water abstraction products, tools, and services identified in the study. These scenarios result in
different types of products, from a basic map of irrigated areas to detailed information on suspicions of
non-authorised abstractions. Member States are increasingly involved in data collection and
production from scenario 1 (not involved) to scenario 4 (full collaboration).
Table 5: Overview of the scenarios for the development of EU products and services for the
detection and/or monitoring of non-authorised abstractions
Scenario Narrative
1 EU Basic overview EU products based on space data and existing pan-EU
databases alone
2a EU-MS Low accuracy EU-MS product based on EU space data and local data from
readily available databases produced by the EU and MS – Low
accuracy
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Scenario Narrative
2b EU-MS High accuracy EU-MS product based on EU space data and EU and local data
from databases produced by the EU and MS and field work –
High accuracy
3 EU-MS-local Complete
legal check
EU-MS product based on the combination of EU space data,
local technical data produced by the EU and MS and MS legal
data
These options differ by the type of governance, degree of sophistication of processing, requirements
of supporting data or models, and involvement of specialised (non-automatic) quality control and/or
local knowledge and expertise. All have in common the basic requirement of dense time series (one
image coverage every 4 weeks, unless specified otherwise below) of high-resolution images (10-30m
pixel) in the solar spectrum, which can be delivered by Sentinel-2 and which have been delivered by a
wide range of EO satellites since 1982 (e.g., Landsat4-8, Spot, IRS, Aster, Formosat, CBERS, Rapid
Eye, Ikonos, Pleiades), and of high-quality basic processing to level-2 products (reflectance values,
radiometrically calibrated, georeferenced with high-precision, and possibly atmospherically corrected).
The primary coverage of interest includes irrigable (as defined in some MS hydrological plans) and
irrigated areas (from the same source and from Eurostat, EEA, FAO, and MS statistics databases),
which would put the focus on Southern MS and would concern about 8% of agricultural areas (i.e.,
154 539 km2). Should the detection exercise be more limited spatially for financial and/or resource
issues, a refined zoom could be relevant on areas fed predominantly by groundwater , in EU roughly
50 000 km2 (about 35% of irrigated areas)
23 (because these have traditionally been more difficult to
monitor by non-EO means, so there is less information available in existing databases).
Each scenario is assessed below following the six steps for EO-based detection of non-authorised
abstractions:
1- Acquisition of EO data and basic processing (radiometric, geometric, and atmospheric
correction and generation of basic products: NDVI maps and colour composites);
2- Generation of overview products (rough estimates of crop phenological curves as well as of
crop coefficient (Kc), crop water requirements (CWR), and irrigation water requirements (IWR)
maps);
3- Generation of maps of irrigated areas and phenology;
4- Generation of maps of Kc, CWR and IWR;
5- Generation of maps of water consumption and water abstraction;
6- Detection of non-authorised abstractions by comparison with legal data of abstraction rights
and water allocation.
They are screened against criteria including:
responsibilities of stakeholders for the production of data, processing and use (EU, MS,
local) ;
accuracy;
data requirements ;
costs.
23
Siebert et al., HydrolEarth.Syst.Sci, 14, 1863-1880, 2010.
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The specificities of each scenario are described in the text below and summarised in comparative
tables (Table 6, Table 7 and Table 8).
Scenario 1: EU product based on space data and existing pan-EU databases alone
The simplest scenario would provide two strands of very basic overview products.
The first strand would be space data and basic products (from EU and other sources) delivered
through a large-scale operational, largely automated production line under the responsibility of the EU
(i.e. Copernicus)). This entails the generation of maps of NDVI (and possibly other simple indices
and/or biophysical variables at large), which can be fully automated, plus maps of colour combination,
the generation of which needs manual supervision by experienced operators. The NDVI overview
maps can be used as a starting point for area selection for zooming in. The time series of NDVI maps
can also be used to extract “NDVI curves” (see below in scenario 2), which can give a very rough idea
of crop phonological curves. The colour combination maps give a first overview of crop vigour and
plant status. They can also be used at any water governance level as a first approximation for
directing field inspection.
The second strand would make use of existing pan-EU (or global) databases of non-EO data
(agrometeorological, precipitation, crop phenology) to calculate first estimates of phenology, crop
coefficient, CWR, and IWR. Both could be implemented fully on the EU level (Copernicus) and
integrated into the Copernicus governance mechanisms.
These products will be of practical use only to water managers (at national and regional level) with
some EO previous experience, so that they can visually assess crop status over wide areas (e.g. in
order to identify hot spots that need more in-depth monitoring). Their advantage lies in their low cost
and the availability of long time series (back to the first years of Landsat coverage in 1972) for
quantitative change assessment. Scenario 1 is a low cost scenario drawing from EO and existing
large-scale databases. The cost for setting up the operational production line will mostly depend on
more detailed specifications than those currently available (for instance, Sentinel-2 data will probably
have NDVI and colour composite included in level-2 products, which would substantially decrease the
costs). For illustrative purposes, however, the cost of implementing scenario 1 for Iberian peninsula
(Spain+Portugal, minus the islands) for one year, based on free images (currently Landsat),
processing & product generation, plus making products available to user via webGIS would be in the
order of magnitude of 0.20-0.50 €/km2/year (depending on the salary level of the personnel, here
calculated in ES).
Scenario 2 (version 2a and 2b): EU-MS product based on EU space data and
supporting local data produced by the EU and MS
Scenario 2 builds on scenario 1 and brings the added value of including the use of non-EU data
available at MS (all levels of water governance). These supporting local data are required for a more
accurate calculation of crop coefficient, crop water requirement, irrigation water requirement and
further products (irrigation water consumption and abstraction), as well as for the mapping of irrigated
areas. Three different kinds of products and/or services can be produced within scenario 2:
maps of irrigated areas ;
calculation of crop coefficient, evapotranspiration / crop water requirements, and
irrigation water requirements;
calculation of irrigation water consumption and abstraction.
For each of these products, two levels of sophistication (and thus, accuracy) can be achieved:
one without ground truthing, leading to scenario 2a (including the production of irrigated
area maps), but with additional information from readily available databases from the
EU and MS compared to scenario 1. There, the processing and product generation for
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scenario 2a can be fully produced at EU level, based on available pan-EU, MS and/or
FAO databases; and
one with ground truthing (defined as calibration and validation of EO-data products
using in-situ data) in addition to readily available databases, leading to scenario 2b.
There, a collaborative mechanism for EU-MS synergy similar to the Copernicus Land
Monitoring, in particular CORINE is required.
i- A set of annual maps of irrigated areas are obtained from supervised crop classification based
mainly on the temporal evolution of NDVI (which in turn is used to generate crop phenological curves).
This requires a temporal resolution of one image coverage every 2-4 weeks during crop growth
periods. The spatial resolution obviously depends on the parcel size statistics of the area. Sentinel-2
will cover 80-90% of parcels in most areas and MS (estimate based on agricultural statistics).
The basic EO data products for this purpose are “NDVI profiles” per pixel (i.e., graphs of NDVI values
versus time, extracted from a time series of images over the same area, which by themselves are still
meaningless). These temporal profiles are available from scenario 1.
The next step is the analysis of these temporal profiles based on local data (including in-situ). It
requires information on the major crop classes in a given MS and their phenology. Knowledge of the
phenological curves is required for the main crops in each area (both irrigated and non-irrigated) as
the contrast between these curves allows for differentiating and thus identifying the crops. Regional
agronomic knowledge and ground truth are the main sources to obtain it. For crops that are more
difficult to identify from EO alone further supporting local information may be required (e.g.
orthophotos or very-high-resolution EO in the case of woody crops, see Table 2).
Colour composite images (RGB24
), generated at EU level (see scenario 1 above), provide visual
support for the classification process. A dynamic visualization webGIS with SOLAP (spatial online
analysis) capability, like SPIDER developed in SIRIUS, is an essential tool for this purpose, as it
allows efficient generation and visual comparison of NDVI temporal profiles and their correlation with
all available supporting data. Expertise and experience in performing this kind of analysis is required in
order to derive meaningful crop classification (based on and including the generation of the
phenological curves of all major crops).
From there, two levels of accuracy can be achieved, following versions 2a and 2b of this scenario:
an EU-wide approach (scenario version 2a, under EU responsibility) would entail the
use of all available and relevant pan-EU (Copernicus, EEA, JRC, Eurostat), MS and
FAO databases on regional soils, crops, and agronomy. Depending on the quantity and
quality of available information in each area the accuracy of resulting classification may
be lower than indicated in the previous chapters. The percentage error of mis-
classification would depend on the areal percentage of “difficult” crops (e.g., woody,
low-ground-cover vegetables, supplemental irrigation areas). However, this approach
would still provide extremely useful information at EU and MS level about irrigated
areas, possibly also their historical development, and current hotspots that would need
more detailed investigation ;
a more accurate approach (scenario version 2b, under shared EU-MS responsibility)
would entail the use of in-situ data involving local/regional collaboration. This would
24
RGB is the common denominator of all high-resolution sensors in the virtual multi-sensor constellation. NIR (Near-infrared
spectroscopy) and SWIR (Shortwave Infrared Imagery) may allow higher spatial resolution but are not included in all satellites in
the virtual constellation.
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need to be integrated into MS governance mechanisms. A CORINE-like mechanism25
of EU-MS collaboration would probably be the most effective and efficient way of
integrating both levels (EO and local) in this case.
In both versions of scenario 2, harmonisation of data, methodology and end-products needs to be
achieved both at MS level (e.g. between different regions or river basins) and at EU level (e.g.,
definition of interoperability standards, agreement on overall relevant crop classes).
Crop classification, and subsequent mapping of irrigated areas, is a multi-annual process in which
knowledge is accumulative improving itself with a basic set-up of the first classification in year 1 and
subsequent annual updates over a period of 3-5 years, at the end of which all major crops in the area
will have been included. Further annual updates are required to follow the dynamic changes in land-
cover patterns, in particular in irrigated areas.
The annual costs for this scenario are estimated to range between 1 and 3 €/km2/year for versions 2a
and 2b, respectively. These costs include in both cases an overhead of 20% for infrastructure
elements, like computer facilities and field instrumentation maintenance, as well as costs for personnel
to perform the image processing and classification generation in the office. In addition, version 2b
includes costs related to the field work corresponding to ground truth calibration and validation,
corresponding to about the same costs as classification without ground truthing (i.e. about 1
€/km2/year).
ii- The calculation of crop coefficient, evapotranspiration / crop water requirements, and
irrigation water requirements26
on a pixel basis (for the subsequent mapping) requires the same
time series of EO images as product i) but at a slightly higher temporal resolution. A temporal
resolution of one image every 1-2 weeks is normally sufficient and the spatial resolution requirement is
the same as above.
Data layers required for this purpose include all previously mentioned products. NDVI and colour
composite maps can be fed from the EU level, while crop classification and maps of phenology could
come either from the (harmonised) EU level (scenario version 2a) or from MS level directly (scenario
version 2b).
The calculation of crop coefficient from NDVI has been demonstrated to be robust and reliably
applicable to a wide range of crops and conditions, although further research could be desirable (see
Chapter 6). Management under controlled deficit irrigation - as could be the case of grape vines and
olives – can be included by means of a combined surface water and energy balance approach. The
subsequent calculation steps - from crop coefficient to crop water requirements and from there to
irrigation requirements - require local/regional data of reference evapotranspiration, precipitation, and
soil characteristics respectively. These data can come either:
from local agro-meteorological stations or MS station networks (in which case this step
would be included in MS governance mechanism) ; or
from EU-wide or global sources (WMO, ECMWF, synergies with the Copernicus land
programme, weather satellites, soil moisture and precipitation satellites).
Version 2a promotes an EU-wide direct approach, under EU responsibility, based on classification and
crop coefficient from EU and MS databases and agromet data coming from any EU-wide network or
from weather satellites (Meteosat Second Generation, currently at experimental stage).
25
CORINE is based on a pan- EU-defined scheme of 44 land cover clases, managed by the EEA, with actual classification products developed in and provided by each MS. 26
With the sequence of calculation steps and required local data indicated in Table 8.
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Version 2b promotes a more accurate approach with in-situ calibration, under shared EU-MS
responsibility.
Optionally, in order to double-check and/or improve the accuracy of evapotranspiration maps, it is
proposed to derive evapotranspiration from EO data on the surface energy balance. It would require
data from the thermal spectrum (currently only Landsat at high resolution, with 120m pixels in the
thermal range; in the future also Sentinel-3 with 1km pixels in the thermal), with local data
requirements similar to the NDVI-based approaches.
The products obtained here do not only serve the immediate focus of this study (i.e. abstractions
monitoring), but also open the way for a wide range of further complementary applications. These
include EO-assisted hydrological planning and monitoring (at national, regional, local level) and
irrigation scheduling (farm advisory at regional and local level), embedded in the corresponding level
governance mechanisms (MS, river basin authority, regional governments, water user associations).
They also provide continuous large area data that could feed into environmental indices (national,
EEA, JRC) and input for numerical weather prediction models (national weather services, ECMWF).
The annual cost of this scenario is estimated to be around 1 €/km2/year, on top of the cost for
classification, for scenarios 2a and 2b, respectively. This includes a 20% infrastructure overhead and
cost of personnel for analysis and product generation. Field calibration and validation cost about the
same as these infrastructure and personnel costs, which again means that the scenario 2a version
cost is roughly 50% of the scenario 2b version cost.
iii- The calculation of irrigation water consumption and abstraction builds on ii) above
(calculation of CWR and IWR). The calculation of irrigation water consumption and abstracted
volumes requires taking into account the efficiencies of the irrigation system and of the conveyor
systems (i.e. the transport of water from its source, e.g. well, pond, canal, to the irrigation system).
This requires local data on system efficiencies. The accuracy of these estimates depends on accuracy
of system efficiency data, which is generally owned by local and regional user organisations. This
opens the way to the monitoring of abstracted water volumes, which can be used e.g. in hydrological
planning and control (national, regional, local levels). While the basic data layers can still come from
EU level (see above, scenario version 2a or 2b), the necessary local data on system efficiencies are
more local and tied to local governance structures. Therefore, these final products/services
can only be generated with a reasonable accuracy at plot level in a scenario version 2b
context.
The annual cost needs to be estimated on a case-by-case basis. If efficiency data are easily available,
the cost would basically be for field calibration/validation (adding about 10-20% to the cost of ii). If
efficiency data are not yet available, cost is likely to be in the same order of magnitude as the
classification step of version 2b.
Summary for Scenario 2
Scenario 2 offers a complete portfolio of data products and information for agricultural water
management and abstractions monitoring, with cost increasing according to the level of completeness.
Its “fast-track” option (version 2a) could provide a suite of products generated at EU level based on
information provided by the EU and MS and managed under the responsibility of the EU, while version
2b could be the basis for more accurate and detailed products and services incorporated into MS
services, with MS in charge of final quality control and service provision.
Scenario 2a products could be generated fully at EU level using relevant EU coordinating mechanisms
(Copernicus, JRC, EEA), while scenario 2b products would need to be generated via an integrated
EU-MS approach, possibly similar to the CORINE process. The collaboration with local/regional
service providers in either version would always have the advantage of fully benefiting from locally
available expertise and proximity to the local area.
The final products could be delivered at both the national level (relevance to MS competencies) and at
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the EU level (in order to enable their use in transboundary river basin management and EU-wide
databases). The most relevant option would be to provide an EU-wide service based on the collection
of data at the national and/or regional level and their harmonisation at the EU level.
Scenario 3: EU-MS product based on the combination of EU space data, local
technical data produced by the EU and MS and MS legal data
A third, complete scenario consists of all of the above, plus databases on legal water rights, which
enables the monitoring and control of irrigated areas and water abstractions. Databases of legal water
rights are in the competencies of MS and/or regional or local water authorities (by means of
delegation), so the corresponding governance would need to be coupled to these levels.
The details for this scenario are the same as above in scenario 2, the only difference being the
availability of geospatial legal reference data. Therefore, the cost is also essentially the same as for
scenario 2. The additional human resources required to actually analyse the comparison of EO-based
abstraction data with the legal reference (which by itself is assumed to be integrated as an additional
layer in the system) is on one hand small compared to the overall task and is on the other hand part of
the routine tasks of the user, independently of any EO-based service.
It should be noted though that this analysis step requires an easy-to-use webGIS that facilitated the
visualization and online analysis of the complete portfolio of data and information products. Therefore,
the users would need some minimum technical capabilities and understanding in order to upload their
legal reference data to the webGIS.
Comparative analysis of the three scenarios:
Table 6 synthesises the main characteristics of each scenario.
Table 6: Summary of main characteristics of each scenario
Scenario Accuracy Required non-EO data Cost
from large-scale
databases
from field work
1: Basic
overview
very low Y N low
2a: Reduced
accuracy
low Y N moderate
2b: High
accuracy
high Y Y high
3: Complete
legal check
high N Y very high
Legend:
Shortcomings Advantages
Table 7 gives an overview of the key elements of the different scenarios to implement this procedure
under the umbrella of Copernicus. Table 8 p.40 summarises the corresponding data requirements.
Details are described in the text below.
Use of Earth observation by water managers to detect and manage non-authorised water abstractions
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Table 7: Overview of responsibilities for each scenario and step in procedure to detect non-
authorised abstraction
a. Data sources:
Step Scenario 1 2a 2b 3 Comments
1 EO data & basic
products (NDVI
maps & curves,
colour composite)
EU EU EU EU Use of Sentinels data
and the Copernicus
space Data Access
mechanism for the
access to other
contributing missions
(high and very-high-
resolution data)To be
complemented with
Landsat if
appropriate
2 Overview products
(rough phenological
curves, rough
estimate of Kc,
CWR, IWR)
EU EU+MS EU+MS EU+MS To be complemented
with international
databases (e.g.,
FAO)
3 Maps of irrigated
areas & phenology
EU+MS EU+MS EU+MS MS data also from
RBA+WUA
4 Maps of Kc, CWR,
IWR
EU+MS EU+MS EU+MS MS data also from
RBA+WUA
5 Maps of
consumption,
abstraction
MS MS
MS data mostly local
6 Check against legal
data (abstraction
rights, water
allocation)
MS
From all levels of
water governance
within MS
b. Processing and product generation:
Step Scenario 1 2a 2b 3 Comments
1 EO data & basic
products (NDVI
maps & curves,
colour composite)
EU EU EU EU multi-sensor
constellation
2 Overview products
(rough phenological
curves, rough
estimate of Kc,
CWR, IWR)
EU EU EU EU EO data
+ non-EO pan-EU
& MS databases
(no field
validation)
3 Maps of irrigated
areas & phenology
EU EU+MS EU+MS “EU+MS” in
CORINE-like
mechanism
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Step Scenario 1 2a 2b 3 Comments
4 Maps of Kc, CWR,
IWR
EU EU+MS EU+MS idem
5 Maps of
consumption,
abstraction
MS MS all levels in MS
6 Check against legal
data (abstraction
rights, water
allocation)
MS all levels in MS
c. Possible uses and targeted users:
Step Scenario Use purpose
1 EO data & basic products (NDVI maps &
curves, colour composite)
rough indication for directing field inspections
2 Overview products (rough phenological
curves, rough estimate of Kc, CWR, IWR)
identification of hotspots
3 Maps of irrigated areas & phenology monitoring of irrigated areas
4 Maps of Kc, CWR, IWR monitoring of irrigation requirements
5 Maps of consumption, abstraction monitoring of abstractions
6 Check against legal data (abstraction rights,
water allocation)
detection of non-authorised abstractions
Legend:
WUA=Water Users Association
RBA=River Basin Authority
Targeted users mostly include the relevant services of the European Commission, the River basin
authorities, the water users associations (including farmers), as well as other interested stakeholders
such as non-governmental organisations.
Use of Earth observation by water managers to detect and manage non-authorised water abstractions
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Table 8 summarises the requirements for implementing each scenario.
Table 8: Requirements for the development of Copernicus water abstraction tools and services
Pan-EU level
(provided by
Copernicus)
Technical requirement Local data requirement /
operational level
Scenario 1
NDVI maps &
temporal
profiles
dense time series of high-
resolution (10 m max)
optical images (Sentinel-2
& coordinated missions);
radiometrically calibrated
and georeferenced with
high precision, possibly
atmospherically corrected;
conversion of digits into
NDVI;
extraction of NDVI temporal
profiles by SOLAP drilling
no local data requirements;
suitable for large-scale operational production line
Maps of colour
combination
same as above;
conversion of red-green-
blue bands into colour
combination
no local data requirement; large-scale operational
production line with manual supervision by
experienced operator
Maps of Kc,
CWR, IWR
(uncalibrated)
conversion NDVIKc
(generic equation);
conversion ET=Kc*Eto ;
IWR=CWR-precip
ETo from Meteosat or WMO or weather prediction
model;
precip from PROBA;
large-scale operational production line
Scenario 2 - i 2a 2b
Maps of
irrigated areas;
georeferenced
crop phenology
curves
same as above;
crop classification based on
temporal evolution of NDVI
ground truth data from
EU &/or MS databases
(of crop identification);
large-scale operational
production line
manual supervision of
classification;
+ ground truth data from
field (in-situ);
manually controlled
production line
Use of Earth observation by water managers to detect and manage non-authorised water abstractions
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Pan-EU level
(provided by
Copernicus)
Technical requirement Local data requirement /
operational level
Scenario 2 –ii 2a 2b
Crop coefficient
maps;
Crop water
requirement
maps;
Irrigation water
requirements;
same as above +
conversion NDVIKc;
conversion ET=Kc*Eto ;
IWR=CWR-precip
ground truth data from
EU/MS databases:
ETo from agromet
network WMO or
Meteosat or weather
prediction models;
precipitation data from
EO (PROBA);
large-scale operational
production line
+ ground truth data from
field work & local
stations (agromet & rain
gauges) (in-situ);
manually controlled
production line
Scenario 2 –iii 2a 2b
Irrigation water
consumption &
abstraction
multiply by system &
conveyor efficiencies
-
(no EU level data)
efficiencies of irrigation
systems and conveyor
systems (local data);
ground truth data from
flow meters (in-situ);
manually controlled
production line
Scenario 3
Integrated
abstractions
monitoring and
control service
same as all above, in
overlay with spatial water
rights database
-
(no EU level data)
legal data on water
rights (MS, RBA, WUA);
locally controlled
production line
5.3. Suggested roadmap for scenario selection and implementation
As requested in the Blueprint impact assessment, a Guidance document for MS has been developed
in the context of this study. So, the first step in the roadmap towards implementation is to inform MS
authorities in the context of the WFD about the document and the options. MS can then review their
situation and check their enabling environment against the requirements for implementation of EO-
based abstractions monitoring. Once MS have identified missing capabilities at MS level, they can
proceed to assess financing needs and potential funding sources.
In parallel, the identified scenarios should be assessed at EU level (in particularly in the context of
Copernicus) against their own capabilities (in terms of strategy, synergy with other sectors, and
financing) before implementing the selected scenario at EU level (contracting, specification and set-up
of the production line and distribution mechanisms, documentation). From that moment on the
continuous production of pan-EU maps of irrigated areas and abstracted volumes would be launched.
Use of Earth observation by water managers to detect and manage non-authorised water abstractions
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Table 9 summarises the main steps in the process, where steps 1-4 run in parallel in MS and EU.
Table 9: Roadmap towards implementation: overview.
MS level Step 1 Information to Member States in the context of WFD about the
development of a pan-EU product, its possible applications, and
communication about the requirements at different scales to be able to
use it: water rights / GIS, etc.;
Step 2 Status of the enabling environment in Member States, at different
scales, against the identified requirements to be able to use the EU
products;
Step 3 Assessment of funding needs from MS based on existing capabilities;
Step 4 Identification of funding options from the EU and Member States;
EU level Step 1 Scenario selection at EU level (in particular in the context of
Copernicus);
Step 2 Implementation at EU level;
Step 3 Production of the EU-wide maps for irrigated areas and water use, and
publication of EU guidelines for their use at national level;
Step 4 Production of documentation (manuals, demonstration cases) for MS
that supports implementation (i.e. for use at regional/local level).
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6. Further research needs
6.1. Maps of irrigated areas
Fully automated EO-based crop classification procedures have recently been published (e.g., Yan and
Roy, 2014), based on a very small number of validation cases. More research is needed in order to
understand the limitations of applicability of these object-based algorithms. They also rely on dense
time series of EO images, i.e. the same data as used in the multi-temporal phenology-based approach
proposed in this study. The potential synergies and application strategies need to be investigated.
In general, further research should be conducted to improve the capability to identify irrigated areas
based on captured reflectances and temperature by a dense time series of EO images at the
adequate spatial and temporal scales. Concrete research needs include:
to build a multisensor constellation to alleviate cloudiness;
the full exploitation of new Sentinels and Copernicus data and services
to integrate all classification procedures to improve the reliability of maps of irrigated
areas, by incorporating all EO and non-EO sources. Particular attention should be given
to crops that receive supplementary irrigation and woody crops with management under
stress.
6.2. Evapotranspiration and abstraction monitoring
Remote sensing estimation of evapotranspiration, i.e. crop water requirements, based on crop
coefficient estimates from multispectral imagery is mature and operational and has been validated in a
wide range of conditions. However, further calibration and validation of the relationship between basal
crop coefficient and vegetation indices (and biophysical parameters in general) should still be
performed for more conditions.
Also further studies on complementary aspects of water balance (NDVI)-based and energy balance
(thermal)-based approaches to estimate crop evapotranspiration could help increase the accuracy of
products in scenario 2 (both the fast-track 2a and the high-accuracy 2b versions). In particular, a
combined strategy to explore the advantages and avoid the pitfalls of each approach should be
developed and validated in a representative range of cases.
Maps of reference evapotranspiration and past rainfall, which are based on meteorological data, could
be improved by incorporating the most recent advances of meteorological modelling research.
Better monitoring and mapping of water stress would also require additional research involving EO
and non-EO aspects. EO could address the mapping of water stress by coupling actual ET estimates
using recorded temperature and surface energy balance modelling together with soil water balance
fed by crop coefficients derived from multispectral imagery. Difficulties arise, however, in 3D crops
with a large fraction of bare soil.
Soil moisture estimates based on radar (e.g., Sentinel-1, SMOS, SMAP) could help improve the
accuracy of CWR and IWR products, but need to be further developed for operational purposes and
carefully calibrated/validated for a representative range of cases.
Space-based precipitation data (e.g., Proba-V) can increase the operational potential and decrease
Use of Earth observation by water managers to detect and manage non-authorised water abstractions
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the cost of products, but further calibration/validation studies are needed.
6.3. Governance
Further research needs concern the adequate governance types for the implementation of EO-based
tools and services, for both the mapping of irrigated areas and the monitoring of abstraction and the
strategy to drive field inspections. In particular the legal conditions need to be analysed and adequate
ways need to be sought to establish the policy, legislative, and administrative framework that will
eventually allow for recognising the EO-based maps of irrigated areas and abstracted volumes as
legal evidence. The situation in Spain (where EO-based information has been accepted as legal
evidence by the Supreme Court) can serve as a guiding reference here, as well as the body of
knowledge available in the U.S. on forensic GIS and EO.
Use of Earth observation by water managers to detect and manage non-authorised water abstractions
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