Folie 1

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Groundwater body delineation - What assistances
doesthe Common Implementation Strategy (CIS)for
the Water Framework Directive (WFD)give?
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IntegratedRiver Basin Management
and other European Directives
Water Framework Directive
River Basin Management Plan
Delineation and Characterisation of Water Bodies
Surface water
Groundwater Description of the river basin
Delineation of groundwater bodies
Establishment of reference conditions
Characterisation of groundwater bodies
Delineation of water bodies
Identification of pressures and risk analysis
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IntegratedRiver Basin Management
and other European Directives
Water Framework Directive
River Basin Management Plan
Delineation and Characterisation of Water Bodies
Groundwater
Next seminar
Delineation of groundwater bodies
Characterisation of pressures and
Characterisation of the overlying
impacts of human activity strata and of its
protection Assessment of the
risk of failing effect for the nearest surface
to meet the objectives under
groundwater body
WFD Article 4 (good status)
Todays seminar
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Delineation of groundwater bodies - Helpful
Common Implementation Strategy (CIS) documents

• Identification of Water Bodies Guidance
  document No. 2 June 2003
• Groundwater body characterisationTechnical
  report on groundwater body characterisation
  issuesas discussed at the workshop of 13th
  October 2003 April 2004

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Delineation of groundwater bodies - General
comments

• The Water Framework Directive (WFD) covers all
  waters, including surface water, groundwater and
  transitional and coastal waters.This totality of
  waters is, for the purpose of the implementation
  of the directive, attributed to geographical or
  administrative units, in particular the river
  basin, the river basin district and the water
  body WFD, Article 2.
• The water body should be a coherent sub-unit in
  the river basin (district) to which the
  environmental objectives of the directive must
  apply. Hence, the main purpose of identifying
  water bodies is to enable the status to be
  accurately described and compared to
  environmental objectives.

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Delineation of groundwater bodies -
Definitions

• Aquifer means a subsurface layer or layers of
  rock or other geological strata of sufficient
  porosity and permeability to allow either a
  significant flow of groundwater or the
  abstraction of significant quantities of
  groundwater WFD, Article 2 (11).
• Body of groundwater (groundwater body) means a
  distinct volume of groundwater within an aquifer
  or aquifers WFD, Article 2 (12).
• It means A groundwater body must be within an
  aquifer or aquifers.However, not all groundwater
  is necessarily within an aquifer.
• Look out! It should be noted that all groundwater
  is subject to the prevention or limitation of the
  input of pollutants whether or not it is
  identified as being part of a groundwater body.

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Delineation of groundwater bodies -
Criteria for qualifying geological strata as
aquifers
In practice, these criteria mean that nearly all
groundwater would be expected to be within
aquifers.
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Delineation of groundwater bodies -
Principles
The definitions in the Water Framework
Directive dont provide an explicit guidance
on how bodies should be delineated.
The delineation of bodies of groundwater must
ensure that the relevant objectives of the
Directive can be achieved. This does not mean
that a body of groundwater must be delineated
so that it is homogeneous in terms of its
natural characteristics, or the
concentrations of pollutants or level alterations
within it.
However, bodies should be delineated in a way
that enables an appropriate description of
the quantitative and chemical status of
groundwater.
For facilitation of the assessment of
quantitative status the delineation of
groundwater bodies should be in such a way that
any groundwater flow from one groundwater
body to another - is so minor that it can
be ignored in water balance calculations or
- can be estimated with adequate precision.
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Delineation of groundwater bodies -
Principles
Groundwater bodies must be assigned to a river
basin or river basin district respectively.
An sub-division (fragmentation) of groundwater
into unmanageable numbers of groundwater
bodies should be avoided in order to reduce
administrative burden.
Groundwater body sizes between 100 km2 and 500
km2 are reasonable.
The delineation of groundwater bodies should
be regarded as an iterative process, possibly
refined over the time.
However, groundwater bodies have to be fixed
for each plan period.
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Delineation of groundwater bodies -
Possible different approaches
In the case of hard rock areas, usually with only
a few monitoring wells, it is recommended to use
hydrological boundaries (surface watersheds of
river sub-basins) as an approximation for
geological boundaries to groundwater flow in
near-surface aquifers. ? The underground
watershed is equated with the surface
watershed.? As a rule, this approach is a
horror vision for hydrogeologists,
especially with regard to karst aquifers.? But
without a good knowledge of the hydrogeological
situation this approach is a pragmatic
procedure, especially in hard rock areas with
only few monitoring wells.
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11
Delineation of groundwater bodies -
Possible different approaches
In the case of hard rock areas, usually with only
a few monitoring wells,it is recommended to use
surface watersheds as an approximation for
geological boundaries to groundwater flow in
near-surface aquifers.
1
Outcropping hard rock
Surface watershed(approximately)coinciding
withthe underground watershed
12
Delineation of groundwater bodies -
Possible different approaches
In the case of unconsolidated rock areas (usually
with a lot of monitoring wells)it is recommended
to use groundwater highs (hydroisohypses)
foridentifying the geological boundaries to
groundwater flow.
2
Outcropping unconsolidated rock
Surface watershed
Underground watershed
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Delineation of groundwater bodies -
Possible different approaches
Application of a combination of hydrological
boundaries (surface watersheds of river
sub-basins) with geological boundaries
(hydrogeological units)
3
Outcropping hard rock (4 units)
Hydrogeological unit 4 Groundwater body 4
Hydrogeological unit 3 Groundwater body 3
Hydrogeological unit 1 Groundwater body 1
Surface watershed
Hydrogeological unit 2 Groundwater body 2
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Delineation of groundwater bodies - Summary
of the recommended hierarchical approach
An aquifer is a geological strata that provides
signifi-cant flow to surface eco-systems and/or
that permits abstraction of significant
quantities of groundwater.
Identify aquifers
Provisionally identify ground-water body on
geological boundaries to flow
Can the status of groundwater be
accurately described at this scale?
On-going iterative refinement using information
from WFD Annex II 2 (characterisation) and WFD
Artic-le 8 (monitoring)
Yes
No

• Sub-divide using
• Geological boundaries
• Groundwater highs
• Flow lines

Confirm as a groundwater body