To define the main water body marginal wetland area to be assessed'

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Modifications to incorporate FAPS for LMW
2.1.A ASSESSMENT AREA (AA) DELINEATION MAP
PREPARATION
To define the main water body marginal wetland
area to be assessed.
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Sea / Estuary Inland (non-marine) water Beach /
Mudflat / Cliffs Saltmarsh Non-agricultural
grassland / Rough pasture / Amenity grassland /
Shrub and Heathland Managed grassland Mixed
deciduous woodland Orchard Coniferous
woodland Bogs and marsh Ploughed land Suburban /
Agricultural development Urban development Bare
ground / Rocks and screes
The following may be added (also in section
iii-2.1.C.1) Industrial/commercial areas
(transport installations, mines, quarries, pits)
(CORINE Land Cover)
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2.2.C Subdivide AA components into HGMUs C.2.
Action, Instruction 7
backswamp
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HGMU3stream/ditch
HGMU3stream/ditch
HGMU2
HGMU1
HGMU2
HGMU1
groundwater table
Groundwater table
Streams/ditches may separate areas with different
inundation or groundwater regimes
HGMU3 embankment
HGMU3embankment
HGMU1
HGMU2
HGMU2
HGMU1
Groundwater table
Embankments may separate flooded from non-flooded
units
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Lines separating drained areas from non-drained
areas
HGMU1
HGMU1
HGMU2
HGMU2
Groundwater table
Drainage will lower groundwater table and affect
hydrology
Hydrological management boundaries The following
modifications to the site are likely to relate
to, or result in, transitions in the hydrology of
the site, and therefore representing HGMU
boundaries Embankments may separate flooded from
non-flooded units (it should be remembered that
embankments are also HGMU types with a geomorphic
code (Instruction 7)). Streams and larger ditches
(gt 1 m wide) may separate areas with different
inundation or groundwater regimes (it should be
remembered that these are also HGMU types with a
geomorphic code (Instruction 7)). Lines
separating intensively drained areas (intervals
between drains approximately lt50 m) from
non-drained areas (intervals between drains gt 50
m). Only consider these when drained and
non-drained areas are clearly discernible and the
drainage system is functioning fully. Drainage
will lower the groundwater tables and thereby
affect the hydrology.
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Recharge area
HGMU high porosity
Runoff
Water body
Aquifer
Groundwater discharge
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F.2. Action determine occurrence of runoff
input A. The process of runoff input into the
HGMU is unlikely to occur if at least one the
following statements is true.
canalditch stream
Assessment Area
embankment
HGMU
HGMU
Groundwater table
Groundwater table
Statement 2 The HGMU is separated from the
upslope area by a feature that will intercept
runoff.
Statement 1 No area (inside or outside the AA)
of significant size immediately upslope of the
HGMU.
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F.2. Action determine occurrence of runoff
input B. The process of runoff input into the
HGMU is very likely to occur if it is directly
upslope of an area larger than itself and the
following statement is true.
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recharge area(gravel, coarse, sand)
F.3. Action determine occurrence of runoff
output A. The process of runoff output from the
HGMU is unlikely to occur if at least two of the
following statements are true.
HGMU
Groundwater table
Statement 2 Soil of high permeability upslope of
the HGMU or upslope area in a recharge area.
HGMU
HGMU
30cm
Groundwater table
Groundwater table
Statement 3 Average water table in the HGMU
remains below 30cm below the soil surface or the
soil is dry or moist even after significant
rainfall.
Statement 4The HGMU is near-horizontal and it is
clearly a depression without any outflow.
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F.3. Action determine occurrence of runoff
output A. The process of runoff output from the
HGMU is very likely to occur if at least two of
the following statements are true.
streams
HGMU
HGMU
Groundwater table
Statement 4 There are drains or streams
originating in the HGMU and leading out of it.
Statement 5 The HGMU is located on a steep slope
(gradient code G3)
HGMU
greyish, organic soil(non-)mottle zonefine,
medium, rock
Overbank flooding
HGMU
lt30cm
waterloggedHGMU
HGMU
Groundwater table
Groundwater table
Statement 2 Soil with/without mottling, organic,
waterlogged
Statement 6 The HGMU receives inputs from
discharge or overbank flooding
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F.4. Action determine occurrence of overbank
flooding A. The process of overbank flooding into
the HGMU is unlikely to occur if at least two of
the following statements are true.
HGMU
range of water body fluctuation
Statement 7 The HGMU is located at an elevation
above the probable range of river level
fluctuation.
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F.4. Action determine occurrence of overbank
flooding B. The process of overbank flooding into
the HGMU is very likely to occur if at least two
of the following statements are true.
HGMU1
HGMU2
Statement 7 The HGMU is in open connection with
another HGMU for which it has been found that
overbank flooding is very likely to occur.
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3.1. Hydrological procedures 3.1.C Groundwater
discharge
Groundwater discharge CV1 HGMU location and
geometry Q3 Q4.
Groundwater discharge CV1 HGMU location and
geometry Q5.