Specific key issues

Name of PilotRiver Basin:OdensePilotRiver Basin

Project leader: Harley Bundgaard Madsen

Reporting period:01-01-2003 - 15-09-2003

Status: Water Body (WB) identification for coastal waters

Guidance / ToR
No / Key issues / Specific question / Clarification / Suggestions for improvement
2.0
Identification of Water Bodies / 2.0 - 1 / Surface Waters:
Status of aquatic ecosystems in the river basin / Do the Water bodies identified permit you to provide an accurate description of the status of aquatic ecosystems in your river basin? / Define the status of aquatic ecosystems
LAKES:
Yes.
WFD aim to protect and if necessary improve the quality of all surface waters. We have defined all lakes/ponds > 100 m² as separate waterbodies. The reason for choosing this relatively small size as the lower limit is that ponds are important habitats in Danish nature. They are protected against physical alterations according to the Nature Protection Act, although the present legislation does not presuppose improvements of their ecological quality. If the small lakes and ponds are not identified as water bodies, there would be a risk that they could only be improved to the extend needed to achieve the objectives for water bodies to which they are directly or indirectly connected, cf. flow chart in GD p. 14, fig. 8.
WATERCOURSES:
Yes.
The WB identification is a way of dividing the stream system into appropriate reaches having the same status.
The status is described according to the following elements:
A description of physical and biological status (vegetation and macroinvertebrates) exists for 308 monitoring stations, each being 50 m long. The data are, however, not as detailed as wished in the WFD. The biological status is primarily assessed by use of macroinvertebrates (the Danish Stream Fauna Index).
Quantitative biological data (fish and macroinvertebrates) and quantitative physical data only exist on 38 of the monitoring stations.
Status description of longer reaches is based mainly on physical data from regulatives (made for streams managed by local authorities).
Data are, however, missing for many small watercourses.
Nevertheless, we have preliminarily identified 3 types of streams according to their size (based on stream order, stream width, distance from the source, and area of the catchments).
COASTAL WATERS:
Yes.
The current national proposal for typologization of coastal waters from NERI (Nielsen et al., 2001) leads to 3 types in the PRB-area and thus 3 WB:
1) Inner fjord:
Seden Strand,
2) shallow, mesosaline fjord: Odense Fjord outer fjord,
3) shallow, inner Danish coastal waters between Kattegat and the Baltic Sea:
the area outside the Odense Fjord.
The status of these 3 WBs can be accurately described due to the existing regional and national monitoring programme.
Parts of Odense outer fjord, however, are protected internationally (Natura 2000) as well as regionally (Regional Planning 2001-13). Subdivision of the outer fjord is thus necessary, cf. the recommendations in the GD, and will follow the limits of the different protected areas. This leads to additionally 3 WB in the outer fjord.
Accurate description of these WBs will require a more intensive monitoring programme of each WB. / WATER-COURSES:
Maybe not all the data recommended by the directive are needed for description of the status. And it is presumably necessary to differentiate the level of monitoring: e.g. an intensive program for some stations and a more extensive one for the majority of especially small streams.
2.0
Identification of Water Bodies / Surface Waters:
Minimum size / Which is the minimum size you have identified? / LAKES:
100 m²
WATERCOURSES:
Approx. 1 km in length.
COASTAL WATERS:
Approx. 10 km2 (Seden Strand).
2.0
Identification of Water Bodies / Surface Waters:
Maximum size / Which is the maximum size you have identified? / LAKES:
3,17 km²
WATERCOURSES:
Approx.12 km in length.
COASTAL WATERS:
Approx. 54 km2 (Odense outer fjord). The outer WB-area will probably be somewhat bigger, but as limits are not yet designated between this area and the other open coastal waters, this area is not calculated yet.
2.0
Identification of Water Bodies / Surface Waters:
Very Small Water bodies / Which approach have you taken for very small water bodies? / How to deal with very small water bodies.
LAKES:
In order to make the administration of the large number of the small water bodies practicable, they must be aggregated according to the same type and pressure, e.g. with the same kind of land use and soil characteristics in the catchments. However, we have not carried this procedure out yet.
WATERCOURSES:
Our work is not finished yet, but we are planning to deal with groups of small stream reaches, primarily according to knowledge of pressure and impact, cf. previous section on lakes.
In the DanishPilotBasin small stream reaches (less than 2 m in width) are very important elements of the stream systems (about 70 % of total length) and therefore cannot be disregarded.
COASTAL WATERS:
It will be necessary to group the small WBs according to type, pressure and impact, cf. previous section on lakes, as the resources for monitoring of these WBs are limited. In the water district Fyn, appr. 40 of these small WBs are present. / COASTAL WATERS:
Some examples of aggregation are recommended
2.0
Identification of Water Bodies / Surface Waters:
Types / Is your typology process finalized? How many Water bodies have you identified regarding this typology? / Define types and criteria used.
LAKES:
The process of defining the lake types is still unfinished. The template will be a system described by The National Environmental Research Institute, primarily developed for relatively large lakes, although it may apply to lakes with a surface area > 1 ha.
The principle of the typology is a division according to alkalinity (>/< 0,2 meq/l), colour (>/< 60 Pt/l), salinity (>/< 0,5 ‰) and mean depth (>/< 3 m). This result in 16 theoretical types, but in practise only 11 types.
If, as suggested by Fyn County, lakes are subdivided according to surface area (size classes: 0,001-0,1, 0,1-1, > 1 ha),and if the two salinity classes are supplemented by a class with salinity > 12 ‰ erected especially for coastal lakes, then 17 distinct lakes types may be recognised within the pilot river basin.
WATERCOURSES:
Our typology process is not finished yet.
We have used a Danish preliminary system proposed by The National Environmental Research Institute, Silkeborg, Denmark. This system contains elements of both System A and B and 6 types in all. Thus it divides the watercourses according to position west or east of the Weichsel ice-front line, and thereafter according to size: small, medium and large streams (current criteria: stream order, catchment area, width and distance from source). This means that only three types are relevant in the pilot basin.
Our experience is that stream width and catchment area (perhaps also median minimum water discharge) are the most useful criteria in stream typology.
We consider to supplement the parameters selected with slope.
COASTAL WATERS:
Our typology process is not finished yet, cf. above. The present national suggestion operates with geomorphologically defined regions, and subdivides theese acc. to mean depth, tidal range, exposure and salinity, acc. to system B. The fjords are further categorized in inner fjords, threshold fjords etc, leading to a total of 16 types in the Danish coastal areas.
3 of these types are present in the PRB area.
2.0
Identification of Water Bodies / Surface waters: Iterative process
Information from article 5 analyses and reviews / Which problems/uncertainties have you identified? / Practicalities when implementing article 5. Uncertainties reported.
LAKES:
The knowledge of especially the small lakes and ponds are in most case too poor in order to distinguish between artificial and natural ones, and to assign them to the correct type. This calls for extensive monitoring of this category of lakes.
The reference condition of lakes is generally very poorly known.
WATERCOURSES:
The following questions arise:
How to deal with small stream reaches (the upper and very important parts of the stream systems) in a way that is manageable. How to deal with stream reaches, where the knowledge is missing. How to deal with temporary stream reaches (upper parts of stream systems, which are definitely not wetlands!). How to deal with stream sources (rheocrens, which are definitely not wetlands!).
How to deal with the riparian zone.
COASTAL WATERS:
The knowledge and the monitoring of many of the coastal areas, and especially the minor WB is not sufficient to allow typologization and defining a reference condition. The biological variables are less well known compared to the physical/chemical variables.
2.0
Identification of Water Bodies / Surface waters:
Review of the water bodies identification process / Will you review the water body identification following the article 5 analysis or after the establishment of the monitoring programme? / Revision after the fulfilment of article 5 requirements or after the monitoring.
LAKES:
There is a need for a continuous revision of water body designation, especially when new and improved knowledge accumulates due to the monitoring programme, and because some WB’s may change status.
WATERCOURSES:
A revision will presumably be needed in several cases, partly because our knowledge increases and partly because some WB’s may change status. As quantitative biological and physical data are missing for many reaches, it will be appropriate to review the identification after a new monitoring programme has been in practice.
COASTAL WATERS:
See the answer for the river courses. The same statements are relevant for the coastal waters.
2.0
Identification of Water Bodies / Surface waters:
Pristine waters / Have you identified water bodies with pristine waters? / LAKES:
No.
WATERCOURSES:
No, not quite pristine. Those which are of very good, near reference quality are often very short, with disturbed parts both up- and downstream.
In this county we only have data from 7 historical and 14 present stream reaches with near reference status. The status is primarily described for macroinvertebrates and a few physical parameters.
COASTAL WATERS:
No, but historical data on especially macrophyte vegetation from near-pristine conditions (1888-1908) are available, and in the Odense Fjord, intensive dynamic modelling has been conducted, including a ‘pristine’ scenario.
2.0
Identification of Water Bodies / Surface Waters:
Status of aquatic ecosystems in the river basin / Do the Water bodies identified permit you to provide an accurate description of the status of aquatic ecosystems in your river basin? / Define the status of aquatic ecosystems
Please provide indication on the average quality of status.
LAKES:
For those lakes previously monitored, the data are suitable for describing their ecological quality. Thus, the status of lakes with a surface area > 3-5 ha is well known, in most cases being moderate to bad. The knowledge of smaller lakes is far less comprehensive. However, previous monitoring shows that ecological quality of these water bodies is at least as poor as that for the larger lakes.
WATERCOURSES:
Using the Danish Stream Fauna Index (faunal class ≥5), about 50 % of the stream reaches have good or better quality. It is, however, uncertain, whether this holds using other quality elements than the macroinvertebrate index.
COASTAL WATERS:
For the WBs identified, there is good information on the development and status of environmental quality for the last 25 years. The pressure of nutrient load and hazardous substances is so high, that the biological variables show severe distortion from natural conditions. The status of the areas is judged to be moderate to poor. None of the WBs in the PRB area, or in the total water district Fynfulfils the present environmental goals. Though knowledge of the smaller WBs is more limited, none of the areas monitored so far fulfil the present goals, and their environmental status is worse than in the more open areas.
2.0
Identification of Water Bodies / Surface waters:
Aggregation of water bodies / Which criteria have you applied when aggregating water bodies? / LAKES:
We have not carried any aggregation out yet. However, we intend to aggregate those small lakes and ponds that are not monitored according to their expected type, and to the land use and soil type of their catchments using GIS technology. The soil will be classified as either clayey or sandy, land use described according to the degree of cultivation and to the density of livestock, and present waste water discharges from scattered homes will be identified.
WATERCOURSES:
The work is not finished yet, but we intend to group the small streams according to type and pressure, see paragraph on lakes for examples of pressure criteria.
These groups could be e.g. unregulated reaches with good or bad status, regulated open reaches with good or bad status, or culverted (very bad status) reaches.
COASTAL WATERS:
The work is not finished yet, but we intend to group the small coastal WB according to type and pressure, see paragraph on lakes for examples of criteria.
2.0
Identification of Water Bodies / Surface waters:
Sub-division of water bodies / How have you considered sub-division and which criteria have you used? / LAKES:
There has not been any need for carrying out sub-division of lakes water bodies.
WATERCOURSES:
We do not intend to subdivide identified water bodies.
COASTAL WATERS:
The coastal waters are divided according to typology and to knowledge of biological and physical status. Subdivision according to protected areas has been carried out (see earlier description).
2.0
Identification of Water Bodies / Surface waters:
Physical features / Which physical (geographical and hydromorphological) features have you used when identifying discrete elements of surface water bodies? / LAKES:
Every stagnant freshwater area with a surface area > 100 m² is defined as a lake or pond. Impounded stream reaches are to start with defined as HMWB watercourses even though they may rather function as lakes.
WATERCOURSES:
Stream width and catchment area (typology), stream slope and regulation degree. These data are used together with the Danish Stream Fauna Index, which reflects both water quality and physical quality.
COASTAL WATERS:
System B. See about typology criteria above.
2.0
Identification of Water Bodies / Surface waters:
Protected areas / How have you considered protected areas (e.g. Natura sites, or drinking water sources)? / LAKES:
Lakes located inside habitat areas and bird protection areas have been identified.
WATERCOURSES:
Delimitation of WB’s is carried out in such a manner that there is no conflict with Natura 2000 sites.
COASTAL WATERS:
In the WB designation, the borders of protected areas (Natura 2000-sites) are followed. Bathing water areas, Shellfish-areas etc. will be considered, when the whole coastal area of the water district Fyn is described in 2004.
2.0
Identification of Water Bodies / Surface waters:
Wetlands associated to water bodies / Have you considered wetlands associated to your water bodies? How have you considered the relationship? / Wetlands related to surface waters.
LAKES:
Wetlands located next to lakes are defined as ’normal’ wetlands, acc. to the present national protectional legislation.
WATERCOURSES:
Not done yet.
COASTAL WATERS:
Wetlands bordering the coastal areas are registered due to the same principles as all other wetlands, acc. to the present national protectional legislation.
2.0
Identification of Water Bodies / Ground Waters:
Number of water bodies / How many water bodies have you identified? / At the time 34 aquifers have been identified. From one of the largest aquifers 6 water bodies have been identified. It is presumed that the number of identified water bodies will reach 50-100.
2.0
Identification of Water Bodies / Ground Waters:
Minimum size / Which is the minimum size you have identified? / Due to only one aquifer has been divided into water bodies the answers of the next three questions are based on the characters of the aquifers.
The minimum size of an aquifer is 0.4 km2. 17 of the identified aquifers have an area under 10 km2. 13 of these have an area under 5 km2.
2.0
Identification of Water Bodies / Ground Waters:
Maximum size / Which is the maximum size you have identified? / The maximum size of an aquifer is 186 km2. This aquifer has been divided into 6 water bodies which range in 15-56 km2.
The median size of the aquifers is calculated to 10 km2. It is thereby assumed that the aquifers under the size of 15 km2 shall not been divided into smaller water bodies. It is supposed that the larger aquifers will be divided into smaller water bodies.
2.0
Identification of Water Bodies / Ground Waters:
Very Small Water bodies / Which approach have you taken for very small ground water bodies? / How to deal with very small water bodies.
The minimum size of an aquifer identified is 0.4 km2. It is however assumed that there are numerous aquifers that have the same size. These are not described yet.
A large number of smaller water bodies are close to the ground surface. This groundwater is strongly influenced by agricultural use of fertilizers and pesticides and form point sources in urban areas. These aquifers are therefore not intended to be used for drinking water abstraction. No systematically mapping has been carried out on this groundwater.
2.0
Identification of Water Bodies / Ground waters:
Significant flow in aquifers / When designating groundwater bodies, how have you considered “significant flow”? / The term significant flow has not been considered in identifying aquifers. The reason is that all identified aquifers are intended to provide drinking water at present or in the future.
Due the hydrological and geological characteristics it must be assumed, however that a majority of the aquifers, especially the aquifers that are close to terrain have a significant flow understood in the context of the horizontal guidance.
2.0
Identification of Water Bodies / Ground waters:
Delineation of groundwater bodies / Which criteria have you used when identifying and delineating groundwater bodies? / The aquifers have been evaluated based on groundwater chemical data. In this work nitrate, conductivity and the content of the pesticide metabolite 2,6-dichlorbenzamide has been used.
Based on the distribution of the chemical data the aquifer has been subdivided into water bodies.
2.0
Identification of Water Bodies / Ground waters:
Groundwater boundaries / How have you identified boundaries of groundwater? / The boundaries have been placed on the basis on flow data.
2.0
Identification of Water Bodies / Ground waters:
Wetlands associated to water bodies / Have you considered wetlands associated to your ground water bodies? How have you considered the relationship? / Wetlands related to ground waters
Areas with groundwater potential over terrain surface have been identified. These areas are compared with postglacial freshwater sediments from soil surface map. It is seen that there is very good overlap between the two kinds of areas.
However areas with postglacial freshwater sediments outside the areas with groundwater potential over terrain surface have been identified. It is assumed that these areas are influenced by secondary groundwater.
2.0
Identification of Water Bodies / General issues:
Local and regional circumstances / Which local and regional circumstances have you considered when identifying water bodies?. How have you done it? / GROUND WATER:
After identification of water bodies, geological and hydrological parameters of the water bodies have been described. Furthermore the chemical status of the water bodies has been identified. In the introductory description of the aquifers the same geological, hydrological and chemical parameters have been described. Based on the comparison of the descriptions the differences between the original aquifer and the water bodies can be compared, and it can be evaluated whether the water bodies are correctly identified.
2.0
Identification of Water Bodies / General issues:
Recommendations
General issues to raise
Experience / Which general problems/experiences/recommendations have you encountered when identifying water bodies in your river basin? / General Comments and Suggestions
LAKES:
The most important problem is related to the generally poor knowledge of the status of small lakes and ponds.
WATERCOURSES:
The most important problem is related to the generally poor knowledge of the status of smallest streams.
COASTAL WATERS:
We have only a limited knowledge of the biology of the coastal waters, and many of the smaller WBs are poorly known.
This lack of information will raise problems when subdividing WBs and designating small discrete WBs, according to e.g. protected areas, as previously described.
GROUND WATER:
Several problems have been identified.
In the guidance it is not clear whether it is the aquifers that could or are intended to be used for the abstraction of more than 10 m3 of drinking water a day that shall be identified. Some groundwater could be used for abstraction but are not intended to be used due to pollution, protection of the aquifer or land use.
Our conclusion is that we only describe aquifers that are intended to be used.
More over it is not clear which scale of groundwater bodies that are ideal. In this work it is concluded that, if the scale is too large it is not possibly to work out an appropriate plan to fulfil the environmental objectives for the groundwater bodies. The size of the water bodies therefore have to fulfil two aspects. In the first place it should be possibly to describe the status of the groundwater body, and secondly it should be possibly to work out a plan for the water bodies that fulfils the demands for public participation. Further more it can be difficult to identify these initiatives that can improve the groundwater quality if the size of the water bodies is too large. I is concluded that the size of the groundwater bodies described in annex 2 (Groundwater-body characterisation) is too large to fulfil this purpose.
It can be concluded that there exists sufficient data to identify aquifers and water bodies.
At the end it can be concluded that it is necessary to perform supplementary mapping of the groundwater to get an acceptable resolution of knowledge to work out a plan for protection of the groundwater.

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