Text consolidated by Valsts valodas centrs (State
Language Centre) with amending regulations of:
11 August 2009 [shall come
into force on 15 August 2009];
10 November 2020 [shall come into force on 12 November
2020].
If a whole or part of a paragraph has been amended,
the date of the amending regulation appears in square
brackets at the end of the paragraph. If a whole
paragraph or sub-paragraph has been deleted, the date of
the deletion appears in square brackets beside the
deleted paragraph or sub-paragraph.
|
Republic
of Latvia
Cabinet
Regulation No. 858
Adopted 19 October 2004
|
Regulations Regarding the
Characterisation of the Types, Classification, Quality Criteria
of Surface Water Bodies and the Procedures for Determination of
Anthropogenic Loads
Issued pursuant to
Section 5, Paragraphs four, eight and nine
and Paragraph ten, Clauses 1, 3 and 4
of the Water Management Law
I. General Provisions
1. The Regulation prescribes:
1.1. the characterisation of the types of surface water bodies
and the classification of surface water bodies;
1.2. the procedures for the determination of anthropogenic
loads, as well as the priority substances and the procedures for
limiting the emission thereof;
1.3. high, good, moderate, poor and bad ecological quality
criteria of surface waters, good and poor chemical quality
criteria, as well as ecological potential criteria (also criteria
of good ecological potential) of a heavily modified or artificial
water body.
2. In order to prepare a river basin management plan
(hereinafter - the management plan) and programmes of measures,
as well as to specify the environmental quality objectives to be
included in the management plan (hereinafter - the environmental
quality objective), valsts sabiedrība ar ierobežotu atbildību
"Latvijas Vides, ģeoloģijas un meteoroloģijas centrs" [State
limited liability company Latvian Environment, Geology and
Meteorology Centre] (hereinafter - the Centre), on the basis of
the existing monitoring data and other data obtained, processed
and compiled prior to the development of the management plan over
an extended period of time, shall:
2.1. determine the water body types of rivers, lakes, coastal
and transitional waters according to the criteria set out in
Annex 1 to this Regulation;
2.2. according to the type, divide rivers, lakes, coastal and
transitional waters into surface water bodies;
2.3. classify surface water bodies and heavily modified or
artificial water bodies;
2.4. determine the environmental quality objectives for
surface water bodies and, taking into account the quality of the
particular water body and the impact of anthropogenic load
thereon, determine the surface water bodies at risk of failing
the environmental quality objectives.
[11 August 2009]
3. Upon the request of the Centre, State and local government
authorities shall provide the information at the disposal thereof
and the data necessary in order to characterise the types of
surface water bodies and to assess their quality, as well as to
determine the anthropogenic load of surface water bodies.
[11 August 2009]
II. Characterisation of the Types
of Surface Water Bodies
4. The criteria for the types of surface water bodies referred
to in Annex 1 to this Regulation shall be taken into account in
determining the type of surface water bodies. The type of an
artificial or heavily modified water body shall be determined,
using the criteria of the type of a surface water body most
accurately corresponding to the characteristics thereof.
[11 August 2009]
5. Upon dividing rivers, lakes, coastal and transitional
waters into surface water bodies, substantial circumstances (for
example, impact of anthropogenic load (also morphological changes
of a water reservoir or watercourse), use of waters for
extraction of drinking water, their relation to protected
territories) shall be assessed, as well as the following
conditions shall be complied with:
5.1. only surface water bodies corresponding to the relevant
type of water bodies shall be joined into one water body;
5.2. the water body does not overlap with another water body
and does not cross borders of another water body;
5.3. the water body according to the ecological and chemical
quality is homogeneous;
5.4. waters of the water body are deemed discrete and
significant elements of the hydrographical network.
6. Taking into account the conditions referred to in Paragraph
5 of this Regulation, a separate water body shall be:
6.1. a river or rivers, the catchment basin of which exceeds
100 km2;
6.2. a lake, the surface area of which is 0.5 km2
or more;
6.3. a river which has a smaller catchment basin or a lake
which has a smaller surface area than that referred in
Sub-paragraph 6.1 or 6.2 of this Regulation accordingly, if a
separate water body is necessary in order to achieve the
environmental quality objectives.
[11 August 2009]
7. The surface waters existing in the protected territories
specified in the Water Management Law may be separate water
bodies, if separate water body is necessary in order to ensure
the protection and management of the particular territory and if
such waters are deemed discrete and significant elements of the
drainage system.
III. Procedures for the
Determination of Anthropogenic Load and Procedures for Limiting
the Emission of Priority Substances
8. In order to determine the load caused by anthropogenic
activities for surface water bodies in each river basin district,
the Centre shall:
8.1. compile and analyse information regarding the most
substantial anthropogenic loads, including regarding extraction
of water (taking into account the seasonal fluctuation of
extraction of water, the total quantity of extraction of water
per year and water losses in the distribution system) and
determine such economic activities, which are related to
industry, agriculture, community management and other fields of
activities and due to which:
8.1.1. point or diffuse source pollution occurs;
8.1.2. polluting substances - priority substances and also
substances especially hazardous and hazardous to the aquatic
environment - specified in laws and regulations regarding water
protection are discharged into water;
8.1.3. the hydrological regime or morphology of surface waters
changes, including due to deviation or redistribution of water
flow;
8.2. survey the actual and planned (permitted) type of spatial
planning specified in the spatial plans in effect (if such
spatial plan does not exist, the type of land use shall be
surveyed);
8.3. determine the economic activities, which should be taken
into account when characterising the anthropogenic load of
rivers, lakes, transitional and coastal waters, as well as
artificial and heavily modified water bodies;
8.4. develop criteria, according to which the significance of
anthropogenic loads, as well as the causes, extent and impact of
anthropogenic loads shall be assessed;
8.5. evaluate whether it is possible to achieve the
environmental quality objectives put forward for the water body
or there is a risk of failing them.
[11 August 2009; 10 November 2020]
9. In assessing the anthropogenic load, the Centre shall use
the data of water monitoring and information obtained in
preparing the characterisation of the river basin.
[11 August 2009]
10. Priority substances and hazardous substances and the
procedures for limiting emissions thereof shall be determined in
laws and regulations regarding emissions of polluting substances
into water.
[10 November 2020]
IV. Classification of and Quality
Criteria for Surface Water Bodies, as well as Ecological
Potential Criteria of a Heavily Modified or Artificial Water
Body
11. Surface water bodies shall be divided in ecological
quality classes and chemical quality classes.
12. Surface water bodies, in accordance with the ecological
quality criteria (biological, hydromorphological, chemical and
physico-chemical) specified in Annex 3 to this Regulation and the
explanation of criteria specified in Annex 4, shall be divided
into high (reference) ecological quality class, good ecological
quality class or moderate ecological quality class. If data show
that ecological quality of a water body is worse than the
moderate, it shall be divided into poor ecological quality class
or bad ecological quality class in order to be able to select the
most appropriate measures for improvement of the relevant water
body condition.
12.1 In determining the ecological quality class,
the Centre shall take into account:
12.11. the monitoring data and other data obtained
over an extended period of time;
12.12. the results of modelling;
12.13. the load caused by anthropogenic activities
on the water body, which has been determined in accordance with
Chapter III of this Regulation.
[11 August 2009]
13. Ecological quality of a surface water body is high
(reference condition) if it has been established in monitoring
that:
13.1. values of biological, psysico-chemical and
hydromorphological criteria conform to waters of the relevant
type totally or nearly totally undisturbed by anthropogenic
activities and the natural habitats observed are characteristic
to waters of the relevant type;
13.2. synthetic substances (of artificial origin) are not
detected in the water body or their concentration in water is
lower than the concentration to be determined in a laboratory
(such concentration, which may be detected during defining of the
reference condition using available technological methods, shall
be deemed the lowest concentration to be determined);
13.3. the concentration of polluting substances of natural
origin in water detected in the water body conforms to the
background level characteristic to waters of the relevant type
undisturbed by anthropogenic activities.
[11 August 2009]
14. Ecological quality of a surface water body is good if
values of biological and physico-chemical criteria obtained in
monitoring only slightly differ from the values that have been
determined for a surface water body of high quality (reference
condition).
15. Ecological quality of a surface water body is moderate if
values of biological and physico-chemical criteria obtained in
monitoring are lower than the values that have been determined
for a surface water body of good quality.
16. Ecological quality of a surface water body is poor if
values of biological and physico-chemical criteria obtained in
monitoring are lower than the values that have been determined
for a surface water body of moderate quality, and the species and
natural habitats found in the water body significantly differ
from those characteristic to surface water bodies of the relevant
type, which are not affected by anthropogenic activities.
17. Ecological quality of a surface water body is bad if
values of biological and physico-chemical criteria obtained in
monitoring are lower than the values that have been determined
for a surface water body of poor quality, and majority of the
species and natural habitats characteristic to surface water
bodies of the relevant type not affected by anthropogenic
activities are not found in the water body.
18. Artificial and heavily modified water bodies according to
the ecological quality shall be divided into the highest possible
ecological potential class, good ecological potential class,
moderate ecological potential class, poor ecological potential
class or bad ecological potential class. In order to determine
the ecological potential of an artificial or heavily modified
water body, the water body shall be considered as equivalent to
the type of rivers, lakes, water bodies of transitional waters or
coastal waters, to which the characteristics of the artificial or
heavily modified water body correspond to the most. Upon dividing
the particular artificial or heavily modified water body into an
ecological potential class, the ecological quality criteria
specified in this Regulation for the corresponding type of
surface water bodies shall be used.
19. Surface water bodies and artificial and heavily modified
water bodies shall be divided into a good chemical quality class
or poor chemical quality class according to the chemical quality.
Such surface water bodies and artificial and heavily modified
water bodies shall be divided into the good chemical quality
class, the concentration of chemical substances in which does not
exceed the environmental quality norms specified in the laws and
regulations regarding environmental protection.
20. If the monitoring data show that a surface water body,
taking into account different biological, hydromorphological,
chemical or physico-chemical criteria, conforms to different
quality classes (is not homogeneous), it shall be divided into
the lowest quality class.
21. In order to determine which values of the ecological
quality criteria conform to each quality class and to ensure the
mutual comparability of classes, the Centre:
21.1. shall determine the quality criteria values
corresponding to the reference condition (high quality or the
highest possible ecological potential) on the basis of the
monitoring data of reference objects, applying modelling or
combining both of the referred to methods. If it is not possible
to use such methods, the reference condition may be determined,
taking into account an opinion of experts;
21.2. if the reference condition is determined on the basis of
monitoring data, the Centre shall create a network of reference
objects, including therein water bodies belonging to all the
types specified in Annex 1 to this Regulation, conforming to the
high quality (reference condition) class. Such number of
reference objects shall be selected, which allows to determine
credible quality criteria values, taking into account the
variability of the criteria and the information necessary for
modelling;
21.3. if the reference condition is determined by applying
modelling, the Centre shall use information obtained over an
extended period of time, the data on sediment composition and
other data ensuring the credibility and conformity of values of
the criteria characterising the reference condition with the
relevant type of water bodies;
21.4. if it is not possible to determine credible values of
the criteria of reference conditions due to their high natural
variability, the relevant quality criteria need not be used for
the quality assessment of the relevant type. In such case it
shall be justified in the river basin district management plan
why such criteria has not been used;
21.5. values of the highest possible ecological potential
determined for artificial or heavily modified water bodies shall
be reviewed once every six years.
[11 August 2009]
21.1 In order to ensure the comparability of
monitoring systems in the European Union, the Centre shall:
21.11. carry out monitoring in order to obtain data
for the determination of values of biological quality
criteria;
21.12. express the results of the monitoring
referred to in Sub-paragraph 21.1 1 of this Regulation
in the form of ecological quality coefficients, showing the ratio
of the value of biological criteria observed in a water body and
the value of the same criteria in the reference object. The
coefficients shall be expressed in numerical values from zero to
one where the value, which is close to one, shall indicate high
quality class and the values of poor quality class shall be close
to zero;
21.13. express the limits of ecological quality
classes in numerical values, dividing the eocological quality
coefficients in five quality classes;
21.14. ensure the comparison of limit values
between a high and good quality class, as well as between a good
and moderate quality class within the framework of a process for
the comparison of quality assessment systems organised by the
European Union (hereinafter - the intercalibration) and use the
results of intercalibration for determination of the limits of
quality classes;
21.15. a corresponding monitoring of water bodies
shall be carried out for each type selected in the
intercalibration process.
[11 August 2009; 10 November 2020]
V. Closing Provisions
22. Cabinet Regulation No. 93 of 17 February 2004, Regulations
Regarding the Characterisation of the Types, Classification,
Quality Criteria of Surface Water Bodies and the Procedures for
Determination of Anthropogenic Loads (Latvijas Vēstnesis,
2004, No. 30), is repealed.
23. Until 31 July 2009, the tasks specified for the Centre in
this Regulation shall be performed by the State agency Latvian
Environment, Geology and Meteorology Agency.
[11 August 2009]
Informative Reference to European
Union Directives
[11 August 2009]
The Regulation contains legal norms arising from:
1) Directive 2000/60/EC of the European Parliament and of the
Council of 23 October 2000 establishing a framework for Community
action in the field of water policy;
2) Directive 2008/105/EC of the European Parliament and of the
Council of 16 December 2008 on environmental quality standards in
the field of water policy, amending and subsequently repealing
Council Directives 82/176/EEC, 83/513/EEC, 84/156/EEC,
84/491/EEC, 86/280/EEC and amending Directive 2000/60/EC of the
European Parliament and of the Council.
Prime Minister I. Emsis
Minister for Environment R. Vējonis
Annex 1
Cabinet Regulation No. 858
19 October 2004
Types of Surface Water Bodies
[11 August 2009; 10 November
2020]
1. Rivers
No.
|
Area of the catchment
basin
|
Longitudinal gradient of the
bottom of the bed (in a 1-3 km section)
|
Type
|
Characterisation of the
type
|
1.1. |
Small
(< 100 km2) |
Large
(> 1.0 m/km) |
Small ritral-type river |
The river is shallow, the speed
of the current exceeds 0.2 m/s. The substrate of the bed is
formed by sand, gravel and rocks |
1.2. |
Small
(< 100 km2) |
Small
(< 1 m/km) |
Small potamal-type river |
The river is shallow, the speed
of the current is less than 0.2 m/s. The substrate of the bed
is formed by sand covered in detritus of organic origin and
silt |
1.3. |
Medium large
(100-1000 km2) |
Large
(> 1 m/km) |
Medium ritral-type river |
The river is medium deep, the
speed of the current exceeds 0.2 m/s. The substrate of the
bed is formed by sand, gravel and rocks |
1.4. |
Medium large
(100-1000 km2) |
Small
(< 1 m/km) |
Medium potamal-type river |
The river is medium deep, the
speed of the current is less than 0.2 m/s. The substrate of
the bed is formed by sand covered in detritus of organic
origin and silt |
1.5. |
Large
(1000-10000 km2) |
Large
(> 1 m/km) |
Large ritral-type river |
The river is deep, the speed of
the current exceeds 0.2 m/s. The substrate of the bed is
formed by sand, gravel and rocks, in places by dolomite or
sandstone |
1.6. |
Large
(1000-10000 km2) |
Small
(< 1 m/km) |
Large potamal-type river |
The river is deep, the speed of
the current is less than 0.2 m/s. The substrate of the bed is
formed by sand, in places by dolomite or sandstone, covered
in detritus of organic origin and silt |
1.7. |
Very large
(> 10000 km2) |
Small
(< 1 m/km) |
Very large potamal-type
river |
The river is deep, the speed of
the current is low. The substrate of the bed is formed by
sand, in places by dolomite or sandstone, covered in detritus
of organic origin and silt |
Notes.
1. The types of rivers in Latvia have been specified, using
System B of the European Union.
2. According to the height above sea level, geographical
longitude and latitude all river water bodies of Latvia have been
divided in one class, because significant ecological differences
between rivers have not been observed in Latvia due to such
indicators.
3. Riverbeds of Latvia are mainly of carbonatic origin,
therefore, one class - rivers with carbonate bed - has been
singled out in typology.
4. In determining the individual type of water bodies (rivers) in
accordance with Paragraph 2 of this Regulation, the average speed
of the current shall be calculated in accordance with the
requirements of Cabinet Regulation No. 329 of 30 June 2015,
Regulations Regarding Latvian Construction Standard LBN 224-15
"Amelioration Systems and Hydrotechnical Structures".
2. Lakes
No.
|
Average depth
|
Water hardness
|
Chromaticity
|
Type
|
2.1. |
Very shallow
(< 2 m) |
Hard-water
(> 165 mkS/cm) |
Oligohumous
(< 80 Pt-Co) |
Very shallow clearwater lake
with high water hardness |
2.2. |
Very shallow
(< 2 m) |
Hard-water
(> 165 mkS/cm) |
Polyhumous
(< 80 Pt-Co) |
Very shallow brown-water lake
with high water hardness |
2.3. |
Very shallow
(< 2 m) |
Soft-water
(> 165 mkS/cm) |
Oligohumous
(< 80 Pt-Co) |
Very shallow clearwater lake
with low water hardness |
2.4. |
Very shallow
(< 2 m) |
Soft-water
(> 165 mkS/cm) |
Polyhumous
(< 80 Pt-Co) |
Very shallow brown-water lake
with low water hardness and pH ≥ 5.5 |
2.5. |
Shallow
(2-9 m) |
Hard-water
(> 165 mkS/cm) |
Oligohumous
(< 80 Pt-Co) |
Shallow clearwater lake with
high water hardness |
2.6. |
Shallow
(2-9 m) |
Hard-water
(> 165 mkS/cm) |
Polyhumous
(< 80 Pt-Co) |
Shallow brown-water lake with
high water hardness |
2.7. |
Shallow
(2-9 m) |
Soft-water
(> 165 mkS/cm) |
Oligohumous
(< 80 Pt-Co) |
Shallow clearwater lake with low
water hardness |
2.8. |
Shallow
(2-9 m) |
Soft-water
(> 165 mkS/cm) |
Polyhumous
(< 80 Pt-Co) |
Shallow brown-water lake with
low water hardness and pH ≥ 5.5 |
2.9. |
Deep
(> 9 m) |
Hard-water
(> 165 mkS/cm) |
Oligohumous
(< 80 Pt-Co) |
Deep clearwater lake with high
water hardness |
2.10. |
Deep
(> 9 m) |
Soft-water
(> 165 mkS/cm) |
Oligohumous
(< 80 Pt-Co) |
Deep clearwater lake with low
water hardness |
2.11. |
Very shallow
(< 2 m)
or shallow
(2-9 m) |
Soft-water
(> 165 mkS/cm) |
Polyhumous
(< 80 Pt-Co) |
Very shallow or shallow
brown-water lake with low water hardness and pH < 5.5 |
Notes.
1. The types of lakes in Latvia have been specified, using System
B of the European Union.
2. According to the height above sea level, geographical
longitude and latitude, all lake water bodies of Latvia have been
divided in one class, because significant ecological differences
between lakes have not been observed in Latvia due to such
indicators.
3. Water hardness (electric conductivity) has been selected as an
indicator characterising the geological structure of the lake
bed.
4. According to the size all lake water bodies of Latvia have
been divided in one class - lakes, the water surface area of
which exceeds 50 hectares.
3. Transitional waters
No.
|
Water salinity
(permilles)
|
Average depth (m)
|
Wave exposure
|
Blending
|
Dominant substrate
|
Type
|
3.1. |
0.5 < 5-6 |
< 30 |
Moderately exposed |
Partially stratified |
Silt |
Transitional waters of the Gulf
of Riga |
Notes.
1. The types of transitional waters in Latvia have been
specified, using System B of the European Union.
2. According to the geographical longitude and latitude water
bodies of transitional waters of Latvia have been divided in one
class, because significant ecological differences between
transitional waters have not been observed in Latvia due to such
indicators.
3. The criterion "tidal range" of the System B of the European
Union has not been used because significant tides have not been
observed on the coast of Latvia.
4. Coastal waters
No.
|
Water salinity
(permilles)
|
Average depth (m)
|
Wave exposure
|
Blending
|
Residence time (24-hours)
|
Dominant substrate
|
Type
|
4.1. |
6 < 18-20 |
< 30 |
Exposed |
Complete |
< 7 |
Sand-gravel |
Open sandy south-eastern coast
of the Baltic Sea |
4.2. |
6 < 18-20 |
< 30 |
Exposed |
Complete |
< 7 |
Field stones |
Open rocky south-eastern coast
of the Baltic Sea |
4.3. |
0.5 < 6 |
< 30 |
Moderately exposed |
Complete |
< 7 |
Sand-gravel |
Sandy coast of the Gulf of
Riga |
4.4. |
0.5 < 6 |
< 30 |
Moderately exposed |
Complete |
< 7 |
Field stones |
Rocky coast of the Gulf of
Riga |
Notes.
1. The types of coastal waters in Latvia have been specified,
using System B of the European Union.
2. According to the geographical longitude and latitude water
bodies of coastal waters of Latvia have been divided in one
class, because significant ecological differences between coastal
waters have not been observed in Latvia due to such
indicators.
3. The criterion "tidal range" of the System B of the European
Union has not been used because significant tides have not been
observed on the coast of Latvia.
Minister for Environment R. Vējonis
Annex 2
Cabinet Regulation No. 858
19 October 2004
Priority Substances the Emission
of which Needs to be Limited
[10 November 2020]
Annex 3
Cabinet Regulation No. 858
19 October 2004
Ecological Quality Criteria for
the Classification of Surface Water Bodies
[11 August 2009]
No. |
Quality criteria |
Rivers
|
Lakes
|
Transitional waters
|
Coastal waters
|
1. |
Biological
criteria |
1.1. |
Composition, abundance and
biomass of phytoplankton |
(1)
|
v
|
v
|
v
|
1.2. |
Composition and abundance of
macrophytes |
v
|
v
|
v
|
v
|
1.3. |
Composition and abundance of
zoobenthos |
v
|
v
|
v
|
v
|
1.4. |
Composition and abundance of
fish species |
v
|
v
|
v
|
|
1.5. |
Age structure of fish fauna |
v
|
v
|
|
|
2. |
Hydromorphological
elements supporting the biological elements |
2.1. |
Hydrological
regime |
2.1.1. |
quantity and dynamics of water
flow |
v
|
v
|
|
|
2.1.2. |
residence time |
|
v
|
|
|
2.1.3. |
connection to the groundwater
body |
v
|
v
|
|
|
2.1.4. |
river continuity |
v
|
|
|
|
2.2. |
Morphological
conditions |
2.2.1. |
depth variations |
v
|
v
|
v
|
v
|
2.2.2. |
width variations |
v
|
|
|
|
2.2.3. |
dominant substrate composition
of the bed |
v
|
v
|
v
|
v
|
2.2.4. |
cross-section of the bed |
|
v
|
v
|
|
2.2.5. |
structure of the shore zone |
v
|
|
|
|
2.2.6. |
shore structure |
|
v
|
|
|
2.2.7. |
structure of the tidal zone |
|
|
v
|
v
|
2.3. |
Tidal regime |
2.3.1. |
freshwater flow |
|
|
v
|
|
2.3.2. |
direction of the main
currents |
|
|
|
v
|
2.3.3. |
wave exposure |
|
|
v
|
v
|
3. |
Chemical and
physico-chemical elements supporting the biological
elements |
3.1. |
General
criteria |
3.1.1. |
water transparency |
|
v
|
v
|
v
|
3.1.2. |
thermal conditions |
v
|
v
|
v
|
v
|
3.1.3. |
oxygenation conditions |
v
|
v
|
v
|
v
|
3.1.4. |
salinity |
v
|
v
|
v
|
v
|
3.1.5. |
acidification |
v
|
v
|
|
|
3.1.6. |
concentration of nutrients |
v
|
v
|
v
|
v
|
3.2. |
Polluting
substances |
3.2.1. |
artificial polluting substances
discharged into the particular water body |
v
|
v
|
v
|
v
|
3.2.2. |
other polluting substances
discharged into the particular water body |
v
|
v
|
v
|
v
|
Notes.
1. v - the criterion, according to which the ecological quality
of waters of the relevant group shall be evaluated.
2. (1) - to be assessed only in rivers, length of which exceeds
100 km and area of the catchment basin of which exceeds 1000
km2.
3. - the following standards shall be used for taking of
zoobenthos samples:
3.1. standard LVS EN ISO 5667-3:2007 "Water quality - Sampling -
Part 3. Guidance on the preservation and handling of
samples";
3.2. standard LVS EN 27828:2003 "Water quality - Methods of
biological sampling - Guidance on handnet sampling of aquatic
benthic macro-invertebrates";
3.3. standard LVS EN 28265:2003 "Water quality - Design and use
of quantitative samplers for benthic macro-invertebrates on stony
substrata in shallow freshwaters";
3.4. standard LVS EN ISO 9391:2003 "Water quality - Sampling in
deep waters for macro-invertebrates - Guidance on the use of
colonization, qualitative and quantitative samplers";
3.5. standard LVS EN ISO 8689-1:2004 "Water quality - Biological
classification of rivers - Part 1: Guidance on the interpretation
of biological quality data from surveys of benthic
macroinvertebrates";
3.6. standard LVS EN ISO 8689-2:2004 "Water quality - Biological
classification of rivers - Part 2: Guidance on the presentation
of biological quality data from surveys of benthic
macroinvertebrates".
Minister for Environment R. Vējonis
Annex 4
Cabinet Regulation No. 858
19 October 2004
Criteria for the Determination of
High, Good and Moderate Ecological Quality of Surface Water
Bodies
[11 August 2009]
1. Rivers
No.
|
High status
|
Good status
|
Moderate status
|
1.1. |
Biological criteria |
1.1.1. |
Phytoplankton |
|
The composition of taxonomic groups of phytoplankton
corresponds totally or nearly totally to conditions
undisturbed by anthropogenic activities.
The average phytoplankton abundance is wholly consistent
with the type-specific physico-chemical conditions of
surface water bodies and is not such as to significantly
alter the type-specific water transparency conditions.
Planktonic blooms occur at a frequency and intensity which
is consistent with the type-specific physic-chemical
conditions of surface water bodies.
|
There are slight changes in the
composition and abundance of planktonic taxa compared to the
type-specific communities of water bodies. Such changes do
not indicate any accelerated growth of algae resulting in
undesirable disturbances to the balance of organisms present
in the water body or to the physico-chemical quality of the
water or sediment. A slight increase in the frequency and
intensity of the type-specific planktonic blooms may
occur. |
There are changes in the composition and abundance of
planktonic taxa compared to the type-specific communities
of water bodies exceeding good quality indicators and a
significant undesirable disturbance in the values of other
biological and physico-chemical quality elements may occur.
A moderate increase in the frequency and intensity of
planktonic blooms may occur in comparison to good status.
Persistent blooms of phytoplankton may occur during summer
months.
|
1.1.2. |
Macrophytes and
phytobenthos |
|
The composition of taxonomic groups of macrophytes and
phytobenthos corresponds totally or nearly totally to
conditions undisturbed by anthropogenic activities.
There are no detectable changes in the average
macrophytic and the average phytobenthic abundance.
|
There are slight changes in the
indicators of the composition and abundance of macrophytic
and phytobenthic taxa compared to the type-specific
communities. Such changes do not indicate any accelerated
growth of phytobenthos or higher forms of plant life
resulting in undesirable disturbances to the balance of
organisms present in the water body or to the
physico-chemical quality of the water or sediment. The
phytobenthic community is not adversely affected by bacterial
tufts and coats present due to anthropogenic activity. |
The indicators of the composition of macrophytic and
phytobenthic taxa differ from the type-specific community
and are significantly more distorted than at good status.
Moderate changes in the average macrophytic and the average
phytobenthic abundance are evident in comparison to good
status.
The phytobenthic community may be interfered with and in
some areas, displaced by bacterial tufts and coats present
as a result of anthropogenic activities.
|
1.1.3. |
Benthic invertebrate
fauna |
|
The indicators of the composition and abundance of
taxonomic groups of benthic invertebrate taxa correspond
totally or nearly totally to conditions undisturbed by
anthropogenic activities.
The ratio of disturbance sensitive taxa to insensitive
taxa shows no signs of alteration from levels undisturbed
by anthropogenic activities.
The level of diversity of invertebrate taxa shows no
sign of alteration from levels undisturbed by anthropogenic
activities.
|
There are slight changes in the indicators of the
composition and abundance of benthic invertebrate taxa
compared to the type-specific communities.
The ratio of disturbance-sensitive taxa to insensitive
taxa shows slight alteration from type-specific levels of
water bodies.
The level of diversity of invertebrate taxa shows slight
signs of alteration from type-specific levels undisturbed
by anthropogenic activities.
|
The composition and abundance of benthic invertebrate taxa
differ from the type-specific community more than for good
status. Major taxonomic groups of the type-specific
community are absent.
The ratio of disturbance-sensitive taxa to insensitive
taxa, and the level of diversity, are substantially lower
than the type-specific level and significantly lower than
for good status.
|
1.1.4. |
Fish fauna |
|
The indicators of the composition and abundance of
taxonomic groups of fish correspond totally or nearly
totally to conditions undisturbed by anthropogenic
activities.
All the type-specific disturbance-sensitive fish species
are present.
The age structures of the fish communities show little
sign of anthropogenic disturbance and are not indicative of
a failure in the reproduction or development of any
particular species.
|
There are slight changes in
species composition and abundance from the type-specific
communities. Changes are attributable to anthropogenic
impacts on physico-chemical and hydromorphological quality
elements. The age structures of the fish communities show
signs of disturbance attributable to anthropogenic impacts,
and, in a few instances, are indicative of a failure in the
reproduction or development of a particular species, to the
extent that some age classes may be missing. |
The composition and abundance of
fish species differ from the type-specific community more
than for good status. Changes are attributable to
anthropogenic impacts on physico-chemical and
hydromorphological quality elements. The age structure of the
fish communities shows major signs of anthropogenic
disturbance, to the extent that a moderate proportion of the
type specific species are absent or of very low
abundance. |
1.2. |
Hydromorphological criteria |
1.2.1. |
Hydrological
regime |
|
The quantity and dynamics of
flow, and the resultant connection to groundwaters, reflect
totally, or nearly totally, conditions undisturbed by
anthropogenic activities. |
Conditions consistent with the
achievement of the values of parameters characterising good
ecological quality for biological elements. |
Conditions consistent with the
achievement of the values of parameters characterising
moderate ecological quality for biological elements. |
1.2.2. |
River
continuity |
|
The continuity of the river is
not disturbed by anthropogenic activities and allows
undisturbed migration of aquatic organisms and sediment
transport. |
Conditions consistent with the
achievement of the values of parameters characterising good
ecological quality for biological elements. |
Conditions consistent with the
achievement of the values of parameters characterising
moderate ecological quality for biological elements. |
1.2.3. |
Morphological
conditions |
|
Channel patterns, width and
depth variations, flow velocities, substrate conditions and
both the structure and condition of the riparian zones
correspond totally or nearly totally to conditions
undisturbed by anthropogenic activities. |
Conditions consistent with the
achievement of the values of parameters characterising good
ecological quality for biological elements. |
Conditions consistent with the
achievement of the values of parameters characterising
moderate ecological quality for biological elements. |
1.3. |
Physico-chemical criteria |
1.3.1. |
General
conditions |
|
The values of physico-chemical elements correspond totally
or nearly totally to conditions undisturbed by
anthropogenic activities.
Nutrient concentrations remain within the range normally
associated with waters undisturbed by anthropogenic
activities. Temperature, salinity, oxygen balance, pH level
and acid neutralising capacity do not show signs of
anthropogenic disturbance and remain within the range
normally associated with waters undisturbed by
anthropogenic activities.
|
Temperature, salinity, oxygen balance, pH level and acid
neutralising capacity do not reach levels outside the range
established so as to ensure the functioning of the type
specific ecosystem and the achievement of the values
specified for good ecological status for the biological
quality elements.
Nutrient concentrations do not exceed the levels
established so as to ensure the functioning of the
ecosystem and the achievement of the values of parameters
characterising good ecological quality for biological
elements.
|
Conditions consistent with the
achievement of the values of parameters characterising
moderate ecological quality for biological elements. |
1.3.2. |
Specific synthetic
pollutants |
|
Concentrations close to zero and
at least below the limits of detection of the most advanced
analytical techniques in general use. |
Concentrations not in excess of
the chemical quality requirements set in accordance with the
regulatory enactments regarding environmental quality norms
for surface waters. |
Conditions consistent with the
achievement of the values of parameters characterising
moderate ecological quality for biological elements. |
1.3.3. |
Specific
non-synthetic pollutants |
|
Concentrations remain within the
range normally associated with waters undisturbed by
anthropogenic activities (background levels). |
Concentrations not in excess of
the chemical quality requirements set in accordance with the
regulatory enactments regarding environmental quality norms
for surface waters. |
Conditions consistent with the
achievement of the values of parameters characterising
moderate ecological quality for biological elements. |
2. Lakes
No.
|
High status
|
Good status
|
Moderate status
|
2.1. |
Biological criteria |
2.1.1. |
Phytoplankton |
|
The indicators of the composition and abundance of
taxonomic groups of phytoplankton correspond totally or
nearly totally to conditions undisturbed by anthropogenic
activities.
The average phytoplankton biomass is consistent with the
type-specific physico-chemical conditions of surface water
bodies and is not such as to significantly alter the
type-specific water transparency conditions. Planktonic
blooms occur at a frequency and intensity which is
consistent with the type-specific physic-chemical
conditions of surface water bodies.
|
There are slight changes in the
indicators of the composition and abundance of planktonic
taxa compared to the type-specific communities. Such changes
do not indicate any accelerated growth of algae resulting in
undesirable disturbances to the balance of organisms present
in the water body or to the physico-chemical quality of the
water or sediment. A slight increase in the frequency and
intensity of the type-specific planktonic blooms may
occur. |
There are changes in the composition and abundance of
planktonic taxa compared to the type-specific communities
of water bodies exceeding good status and a significant
undesirable disturbance in the values of other biological
and physico-chemical quality elements may occur.
A moderate increase in the frequency and intensity of
planktonic blooms may occur in comparison to good status.
Persistent blooms of phytoplankton may occur during summer
months.
|
2.1.2. |
Macrophytes and
phytobenthos |
|
The indicators of the composition of taxonomic groups of
macrophytes and phytobenthos correspond totally or nearly
totally to conditions undisturbed by anthropogenic
activities.
There are no detectable changes in the average
macrophytic and the average phytobenthic abundance.
|
There are slight changes in the
indicators of the composition and abundance of macrophytic
and phytobenthic taxa compared to the type-specific
communities. Such changes do not indicate any accelerated
growth of phytobenthos or higher forms of plant life
resulting in undesirable disturbance to the balance of
organisms present in the water body or to the
physico-chemical quality of the water. The phytobenthic
community is not adversely affected by bacterial tufts and
coats present due to anthropogenic activity. |
The indicators of the composition of macrophytic and
phytobenthic taxa differ from the type-specific community
and are significantly more distorted than at good status.
Changes in the average macrophytic and the average
phytobenthic abundance are evident.
The phytobenthic community may be interfered with and in
some areas, displaced by bacterial tufts and coats present
as a result of anthropogenic activities.
|
2.1.3. |
Benthic invertebrate
fauna |
|
The indicators of the composition and abundance of
taxonomic groups of benthic invertebrate taxa correspond
totally or nearly totally to conditions undisturbed by
anthropogenic activities.
The ratio of disturbance sensitive taxa to insensitive
taxa shows no signs of alteration from levels undisturbed
by anthropogenic activities.
The level of diversity of invertebrate taxa shows no
sign of alteration from levels undisturbed by anthropogenic
activities.
|
There are slight changes in the composition and abundance
of invertebrate taxa compared to the type-specific
communities.
The ratio of disturbance-sensitive taxa to insensitive
taxa shows slight alteration from type-specific levels of
water bodies.
The level of diversity of invertebrate taxa shows slight
signs of alteration from levels undisturbed by
anthropogenic activities.
|
The composition and abundance of benthic invertebrate taxa
differ from the type-specific community more than for good
status. Major taxonomic groups of the type-specific
community are absent.
The ratio of disturbance-sensitive taxa to insensitive
taxa, and the level of diversity, are lower than the
type-specific level and significantly lower than for good
status.
|
2.1.4. |
Fish fauna |
|
The indicators of the composition and abundance of
taxonomic groups of fish correspond totally or nearly
totally to conditions undisturbed by anthropogenic
activities.
All the type-specific disturbance-sensitive fish species
are present.
The age structures of the fish communities show little
sign of anthropogenic disturbance and are not indicative of
a failure in the reproduction or development of any
particular species.
|
There are slight changes in
species composition and abundance from the type-specific
communities. Changes are attributable to anthropogenic
impacts on physico-chemical and hydromorphological quality
elements. The age structures of the fish communities show
signs of disturbance attributable to anthropogenic impacts,
and, in a few instances, are indicative of a failure in the
reproduction or development of a particular species, to the
extent that some age classes may be missing. |
The indicators of the
composition and abundance of fish species differ from the
type-specific community more than for good status. Changes
are attributable to anthropogenic impacts on physico-chemical
and hydromorphological quality elements. The age structure of
the fish communities shows major signs of anthropogenic
disturbance, to the extent that a moderate proportion of the
type specific species are absent. |
2.2. |
Hydromorphological criteria |
2.2.1. |
Hydrological
regime |
|
The quantity and dynamics of
flow, level, residence time, and the resultant connection to
groundwaters, reflect totally, or nearly totally, conditions
undisturbed by anthropogenic activities. |
Conditions consistent with the
achievement of the values of parameters characterising good
ecological quality for biological elements. |
Conditions consistent with the
achievement of the values of parameters characterising
moderate ecological quality for biological elements. |
2.2.2. |
Morphological
conditions |
|
Lake depth variation, quantity
and structure of the substrate, and both the structure and
condition of the lake shore zone correspond totally or nearly
totally to conditions undisturbed by anthropogenic
activities. |
Conditions consistent with the
achievement of the values of parameters characterising good
ecological quality for biological elements. |
Conditions consistent with the
achievement of the values of parameters characterising
moderate ecological quality for biological elements. |
2.3. |
Physico-chemical criteria |
2.3.1. |
General
conditions |
|
The values of physico-chemical elements correspond totally
or nearly totally to conditions undisturbed by
anthropogenic activities.
Nutrient concentrations remain within the range normally
associated with waters undisturbed by anthropogenic
activities. Temperature, transparency, salinity, pH level,
oxygen balance and acid neutralising capacity do not show
signs of anthropogenic disturbance and remain within the
range normally associated with waters undisturbed by
anthropogenic activities.
|
Temperature, transparency, salinity, pH level, oxygen
balance and acid neutralising capacity do not reach levels
outside the range established so as to ensure the
functioning of the type specific ecosystem and the
achievement of the values specified for good ecological
status for the biological quality elements.
Nutrient concentrations do not exceed the levels
established so as to ensure the functioning of the
ecosystem and the achievement of the values of parameters
characterising good ecological quality for biological
elements.
|
Conditions consistent with the
achievement of the values of parameters characterising
moderate ecological quality for biological elements. |
2.3.2. |
Specific synthetic
pollutants |
|
Concentrations close to zero and
at least below the limits of detection of the most advanced
analytical techniques in general use. |
Concentrations not in excess of
the chemical quality requirements set in accordance with the
regulatory enactments regarding environmental quality norms
for surface waters. |
Conditions consistent with the
achievement of the values of parameters characterising
moderate ecological quality for biological elements. |
2.3.3. |
Specific
non-synthetic pollutants |
|
Concentrations remain within the
range normally associated with waters undisturbed by
anthropogenic activities (background levels). |
Concentrations not in excess of
the chemical quality requirements set in accordance with the
regulatory enactments regarding environmental quality norms
for surface waters. |
Conditions consistent with the
achievement of the values of parameters characterising
moderate ecological quality for biological elements. |
3. Transitional waters
No.
|
High status
|
Good status
|
Moderate status
|
3.1. |
Biological criteria |
3.1.1. |
Phytoplankton |
|
The indicators of the composition and abundance of
taxonomic groups of phytoplankton correspond totally or
nearly totally to conditions undisturbed by anthropogenic
activities.
The indicators of the phytoplankton biomass are
consistent with the type-specific physico-chemical
conditions and are not such as to significantly alter the
type-specific water transparency conditions. Planktonic
blooms occur at a frequency and intensity which is
consistent with the type-specific physico-chemical
conditions.
|
There are slight changes in the indicators of the
composition and abundance of planktonic taxa compared to
the type-specific communities. Such changes do not indicate
any accelerated growth of algae resulting in undesirable
disturbances to the balance of organisms present in the
water body or to the physico-chemical quality of the water.
A slight increase in the frequency and intensity of the
type-specific planktonic blooms may occur.
|
The indicators of the composition of macrophytic and
phytobenthic taxa differ from the type-specific community
and are significantly more distorted than at good status.
Biomass is moderately disturbed and may be such as to
produce a significant undesirable disturbance in the
condition of other biological quality elements.
A moderate increase in the frequency and intensity of
planktonic blooms may occur in comparison to good status.
Persistent blooms of phytoplankton may occur during summer
months.
|
3.1.2. |
Macroalgae |
|
The indicators of the composition of taxonomic groups of
macroalgal taxa correspond totally or nearly totally to
conditions undisturbed by anthropogenic activities.
There are no detectable changes in macroalgal cover due
to anthropogenic activities.
|
There are slight changes in the
indicators of the composition and abundance of macroalgal
taxa compared to the type-specific communities. Such changes
do not indicate any accelerated growth of phytobenthos or
higher forms of plant life resulting in undesirable
disturbance to the balance of organisms present in the water
body or to the physico-chemical quality of the water. |
The indicators of the
composition of macroalgal taxa differ from the type-specific
community and are significantly more distorted than at good
status. Moderate changes in the average macroalgal abundance
are evident compared to good status and may be such as to
result in an undesirable disturbance to the balance of
organisms present in the water body. |
3.1.3. |
Angiosperms |
|
The indicators of the composition and abundance of
taxonomic groups of angiosperms correspond totally or
nearly totally to conditions undisturbed by anthropogenic
activities.
There are no detectable changes in angiosperm abundance
due to anthropogenic activities.
|
There are slight changes in the composition of angiosperm
taxa compared to the type-specific communities.
Angiosperm abundance shows slight signs of
disturbance.
|
The indicators of the composition of angiosperm taxa differ
from the type-specific community and are significantly more
distorted than at good status.
There are moderate distortions in the abundance of
angiosperm taxa compared to good status.
|
3.1.4. |
Benthic invertebrate
fauna |
|
The indicators of the composition and abundance of
taxonomic groups of benthic invertebrate taxa correspond
totally or nearly totally to conditions undisturbed by
anthropogenic activities.
All the disturbance-sensitive taxa associated with
conditions undisturbed by anthropogenic activities are
present.
|
There are slight changes in the
composition and abundance of benthic invertebrate taxa
compared to the type-specific communities. Most of the
sensitive taxa of the type-specific communities are
present. |
The composition and abundance of benthic invertebrate taxa
differ from the type-specific community more than for good
status. Taxa indicative of pollution are present.
Many of the sensitive taxa of the type-specific
communities are absent.
|
3.1.5. |
Fish fauna |
|
The indicators of the
composition and abundance of taxonomic groups of fish
correspond totally or nearly totally to conditions
undisturbed by anthropogenic activities. |
The abundance of the
disturbance-sensitive species shows slight signs of
distortion from type-specific conditions attributable to
anthropogenic impacts on physico-chemical or
hydromorphological quality elements. |
Anthropogenic impact on
physico-chemical or hydromorphological quality elements is so
significant that many type-specific species are absent. |
3.2. |
Hydromorphological criteria |
3.2.1. |
Tidal regime |
|
The freshwater flow regime
corresponds totally or nearly totally to conditions
undisturbed by anthropogenic activities. |
Conditions consistent with the
achievement of the values of parameters characterising good
ecological quality for biological elements. |
Conditions consistent with the
achievement of the values of parameters characterising
moderate ecological quality for biological elements. |
3.2.2. |
Morphological
conditions |
|
Depth variations, substrate
conditions, and both the structure and condition of the
intertidal zones correspond totally or nearly totally to
conditions undisturbed by anthropogenic activities. |
Conditions consistent with the
achievement of the values of parameters characterising good
ecological quality for biological elements. |
Conditions consistent with the
achievement of the values of parameters characterising
moderate ecological quality for biological elements. |
3.3. |
Physico-chemical criteria |
3.3.1. |
General
conditions |
|
Physico-chemical elements correspond totally or nearly
totally to conditions undisturbed by anthropogenic
activities.
Nutrient concentrations remain within the range normally
associated with waters undisturbed by anthropogenic
activities.
Temperature, oxygen balance, salinity and transparency
do not show signs of anthropogenic disturbance and remain
within the range normally associated with conditions
undisturbed by anthropogenic activities.
|
Temperature, oxygen balance,
salinity and transparency, as well as nutrient concentrations
do not reach levels outside the ranges established so as to
ensure the functioning of the ecosystem and the achievement
of the values of parameters characterising good ecological
quality for biological elements. |
Conditions consistent with the
achievement of the values of parameters characterising
moderate ecological quality for biological elements. |
3.3.2. |
Specific synthetic
pollutants |
|
Concentrations close to zero and
at least below the limits of detection of the most advanced
analytical techniques in general use. |
Concentrations not in excess of
the chemical quality requirements set in accordance with the
regulatory enactments regarding environmental quality norms
for surface waters. |
Conditions consistent with the
achievement of the values of parameters characterising
moderate ecological quality for biological elements. |
3.3.3. |
Specific
non-synthetic pollutants |
|
Concentrations remain within the
range normally associated with waters undisturbed by
anthropogenic activities (background levels). |
Concentrations not in excess of
the chemical quality requirements set in accordance with the
regulatory enactments regarding environmental quality norms
for surface waters. |
Conditions consistent with the
achievement of the values of parameters characterising
moderate ecological quality for biological elements. |
4. Coastal waters
No.
|
High status
|
Good status
|
Moderate status
|
4.1. |
Biological criteria |
4.1.1. |
Phytoplankton |
|
The indicators of the composition and abundance of
phytoplanktonic taxa are consistent with conditions
undisturbed by anthropogenic activities.
The average phytoplankton biomass is consistent with the
type-specific physico-chemical conditions and is not such
as to significantly alter the type-specific water
transparency conditions.
Planktonic blooms occur at a frequency and intensity
which is consistent with the type-specific physico-chemical
conditions.
|
The composition and abundance of phytoplanktonic taxa show
slight signs of disturbance. Such changes do not indicate
any accelerated growth of algae resulting in undesirable
disturbances to the balance of organisms present in the
water body or to the physico-chemical quality of the water.
A slight increase in the frequency and intensity of the
type-specific planktonic blooms may occur.
|
The composition and abundance of planktonic taxa show signs
of moderate disturbance.
Algal biomass is substantially outside the range
associated with type-specific conditions, and is such as to
impact upon other biological quality elements.
A moderate increase in the frequency and intensity of
planktonic blooms may occur in comparison to good status.
Persistent blooms of phytoplankton may occur during summer
months.
|
4.1.2. |
Macroalgae and
angiosperms |
|
All disturbance-sensitive macroalgal and angiosperm taxa
associated with conditions undisturbed by anthropogenic
activities are present.
The levels of macroalgal cover and angiosperm abundance
are consistent with conditions undisturbed by anthropogenic
activities.
|
Most disturbance-sensitive macroalgal and angiosperm taxa
associated with conditions undisturbed by anthropogenic
activities are present.
The level of macroalgal cover and angiosperm abundance
show slight signs of disturbance.
|
A moderate number of the disturbance-sensitive macroalgal
and angiosperm taxa associated with conditions undisturbed
by anthropogenic activities are present compared to good
status.
Macroalgal cover and angiosperm abundance is moderately
disturbed and may be such as to result in an undesirable
disturbance to the balance of organisms present in the
water body.
|
4.1.3. |
Benthic invertebrate
fauna |
|
The indicators of the composition and abundance of
taxonomic groups of benthic invertebrate taxa correspond
totally or nearly totally to conditions undisturbed by
anthropogenic activities.
All the disturbance-sensitive taxa associated with
conditions undisturbed by anthropogenic activities are
present.
|
There are slight changes in the
composition and abundance of benthic invertebrate taxa
compared to the type-specific communities. Most of the
sensitive taxa of the type-specific communities are
present. |
The level of diversity and abundance of invertebrate taxa
is moderately outside the range associated with the
type-specific conditions than at good status. Taxa
indicative of pollution are present.
Many of the sensitive taxa of the type-specific
communities are absent.
|
4.2. |
Hydromorphological criteria |
4.2.1. |
Tidal regime |
|
The freshwater flow regime and
the direction and speed of dominant currents correspond
totally or nearly totally to conditions undisturbed by
anthropogenic activities. |
Conditions consistent with the
achievement of the values of parameters characterising good
ecological quality for biological elements. |
Conditions consistent with the
achievement of the values of parameters characterising
moderate ecological quality for biological elements. |
4.2.2. |
Morphological
conditions |
|
The depth variation, structure
and substrate of the coastal bed, and both the structure and
condition of the inter-tidal zones correspond totally or
nearly totally to conditions undisturbed by anthropogenic
activities. |
Conditions consistent with the
achievement of the values of parameters characterising good
ecological quality for biological elements. |
Conditions consistent with the
achievement of the values of parameters characterising
moderate ecological quality for biological elements. |
4.3. |
Physico-chemical criteria |
4.3.1. |
General
conditions |
|
Physico-chemical elements correspond totally or nearly
totally to conditions undisturbed by anthropogenic
activities.
Nutrient concentrations remain within the range normally
associated with waters undisturbed by anthropogenic
activities.
Temperature, oxygen balance, salinity and transparency
do not show signs of anthropogenic disturbance and remain
within the range normally associated with conditions
undisturbed by anthropogenic activities.
|
Temperature, oxygenation
conditions, salinity and water transparency do not reach
levels outside the ranges established so as to ensure the
functioning of the ecosystem and the achievement of the
values of parameters characterising good ecological quality
for biological elements. Nutrient concentrations do not
exceed the levels established so as to ensure the functioning
of the ecosystem and the achievement of the values of
parameters characterising good ecological quality for
biological elements. |
Conditions consistent with the
achievement of the values of parameters characterising
moderate ecological quality for biological elements. |
4.3.2. |
Specific synthetic
pollutants |
|
Concentrations close to zero and
at least below the limits of detection of the most advanced
analytical techniques in general use. |
Concentrations not in excess of
the chemical quality requirements set in accordance with the
regulatory enactments regarding environmental quality norms
for surface waters. |
Conditions consistent with the
achievement of the values of parameters characterising
moderate ecological quality for biological elements. |
4.3.3. |
Specific
non-synthetic pollutants |
|
Concentrations remain within the
range normally associated with waters undisturbed by
anthropogenic activities (background levels). |
Concentrations not in excess of
the chemical quality requirements set in accordance with the
regulatory enactments regarding environmental quality norms
for surface waters. |
Conditions consistent with the
achievement of the values of parameters characterising
moderate ecological quality for biological elements. |
5. Artificial or heavily modified
surface water bodies
No.
|
Maximum ecological
potential
|
Good ecological potential
|
Moderate ecological
potential
|
5.1. |
Biological criteria |
|
The values of the relevant
biological quality elements reflect, as far as possible,
those associated with the closest comparable surface water
body type, given the physical conditions which result from
the artificial or heavily modified characteristics of the
water body. |
There are slight changes in the
values of the relevant biological quality elements as
compared to the values found at maximum ecological
potential. |
There are moderate changes in
the values of the relevant biological quality elements as
compared to the values found at maximum ecological
potential. |
5.2. |
Hydromorphological criteria |
|
The hydromorphological
conditions are consistent with the only impacts on the
surface water body being those resulting from the artificial
or heavily modified characteristics of the water body once
all mitigation measures have been taken to ensure the best
approximation to ecological continuum, in particular with
respect to migration of fauna and appropriate spawning and
breeding grounds. |
Conditions consistent with the
achievement of the values for the biological quality
elements. |
Conditions consistent with the
achievement of the values for the biological quality
elements. |
5.3. |
Physico-chemical criteria |
5.3.1. |
General
conditions |
|
Physico-chemical elements correspond totally or nearly
totally to the conditions undisturbed by anthropogenic
activities associated with the surface water body type most
closely comparable to the artificial or heavily modified
body concerned.
Nutrient concentrations remain within the range normally
associated with such waters undisturbed by anthropogenic
activities.
The levels of temperature, oxygen balance and pH are
consistent with the those found in the surface water body
type most closely comparable to the artificial or heavily
modified body concerned under conditions undisturbed by
anthropogenic activities.
|
The values for physico-chemical elements are within the
ranges established so as to ensure the functioning of the
ecosystem and the achievement of the values for the
biological quality elements.
Temperature and pH do not reach levels outside the
ranges established so as to ensure the functioning of the
ecosystem and the achievement of the values for the
biological quality elements. Nutrient concentrations do not
exceed the levels established so as to ensure the
functioning of the ecosystem and the achievement of the
values for the biological quality elements.
|
Conditions consistent with the
achievement of the values for the biological quality
elements. |
5.3.2. |
Specific synthetic
pollutants |
|
Concentrations close to zero and
at least below the limits of detection of the most advanced
analytical techniques in general use. |
Concentrations not in excess of
the chemical quality requirements set in accordance with the
regulatory enactments regarding environmental quality norms
for surface waters. |
Conditions consistent with the
achievement of the values of parameters characterising
moderate ecological potential for biological elements. |
5.3.3. |
Specific
non-synthetic pollutants |
|
Concentrations remain within the
range normally associated with waters undisturbed by
anthropogenic activities (background levels). |
Concentration not in excess of
the chemical quality requirements specified in accordance
with this Regulation. |
Conditions consistent with the
achievement of the values of parameters characterising
moderate ecological potential for biological elements. |
Minister for Environment R. Vējonis
Translation © 2021 Valsts valodas centrs (State
Language Centre)