Water Body Baseline Data (WFD Step 1)

Appendix D

Water Framework Directive Assessment

Water Framework Directive Compliance

Assessment

This Appendix reports on a high level assessment to determine the compliance of the developing Local

Flood Risk Management Strategy (LFRMS) with the Water Framework Directive (Directive 2000/60/EC of

23 October 2000 establishing a framework for Community action in the field of water policy) (WFD). It:

1.

Describes the relevant objectives of the WFD;

2.

Describes the relevant baseline conditions for water bodies in the Westminster LFRMS study area;

3.

Identifies the consequences of the proposed strategic objectives for the water bodies;

4.

Identifies opportunities that might be taken to improve water bodies as the LFRMS is implemented.

The Water Framework Directive

Background

The WFD was implemented in England by The Water Environment (Water Framework Directive) (England

and Wales) Regulations 2003. It combines water quantity and water quality issues in an integrated approach to the management of all water bodies at the river basin level. Water bodies include rivers, lakes, estuaries (“transitional” water bodies), coastal waters and groundwater. The WFD effectively supersedes all EU environmental water-related legislation such as the Fisheries and Dangerous

Substances Directives, and now drives the existing licensing and consenting framework in England.

The Directive sets out a framework for each Member State to establish River Basin Districts (RBD), for each of which a River Basin Management Plan (RBMP) must be developed and delivered. Each RBMP sets out the objectives for the water bodies within it. Westminster is located in the Thames RBD. The overall requirement of the Directive is that all water bodies must achieve “good ecological status” or better by 2015 unless there are grounds for derogation. This status is determined by comparison with reference water bodies which are not impacted by human activities.

The ecological status of a water body is expressed in terms of five status classes (high, good, moderate, poor or bad). It is determined by assessing its biology, physio-chemical conditions and hydromorphology. In brief, the overall status is assessed as follows:



The biological assessment criteria uses numeric measures of communities of plants and animals

(fish, invertebrates, plants and algae);



The physio-chemical assessment uses measures such as dissolved oxygen and nutrient levels, which support the biological communities;



The hydromorphological assessment uses measures related to water flow, sediment composition and movement, continuity (in rivers) and the structure and condition of habitats.

The overall ecological status of a water body is determined by whichever of these criteria is assessed to be the poorest. For example, if a water body achieves “good status” for each of physio-chemical assessment and hydromorphological assessment, but only achieves “moderate status” for biological assessment, it would be classed overall as having “moderate ecological status”.

Additionally some water bodies can be identified by the competent authority as requiring chemical assessment, which relates to the presence of potentially polluting chemicals. In this case assessment is based on the concentrations of a range of potentially polluting chemicals (e.g. certain pesticides and industrial chemicals) which are identified in the Annexes to the Directive. The WFD requires that such water bodies should also be of “good chemical status”.

2

SECTION ОШИБКА! ИСПОЛЬЗУЙТЕ ВКЛАДКУ "ГЛАВНАЯ" ДЛЯ ПРИМЕНЕНИЯ HEADING 1 К ТЕКСТУ, КОТОРЫЙ ДОЛЖЕН ЗДЕСЬ ОТОБРАЖАТЬСЯ. ОШИБКА! ИСПОЛЬЗУЙТЕ

ВКЛАДКУ "ГЛАВНАЯ" ДЛЯ ПРИМЕНЕНИЯ HEADING 1 К ТЕКСТУ, КОТОРЫЙ ДОЛЖЕН ЗДЕСЬ ОТОБРАЖАТЬСЯ.

For water bodies which are artificial (e.g. canals and reservoirs) or which are heavily modified by legitimate human activity such as flood defence or navigation the overall requirement is “good ecological potential”, recognising that a fully natural condition is not achievable. Ecological potential means that the water body is managed to support the biology that can be achieved given its modified condition. The quality status of HMWBs is classified by:



Identifying the impacts of physical modifications to the water body;



Identifying mitigation measures necessary to ensure the hydromorphological characteristics of the water body are consistent with good ecological potential; and



Assessing whether those measures have been taken.

WFD Environmental Objectives

The WFD sets out a number of environmental objectives against which plans and projects should be assessed, as follows:



WFD1 - No changes affecting high status sites;



WFD2 - No changes that will cause failure to meet surface water good ecological status / potential or that will result in a deterioration of surface water ecological status / potential;



WFD3 - No changes which will permanently prevent or compromise the environmental objectives being met in other water bodies;



WFD4 - No changes that will cause failure to meet good groundwater status or result in deterioration in groundwater status.

It should be noted that WFD references to “surface waters” encompass river, lake, transitional, coastal and artificial water bodies, as distinct from urban surface drainage / runoff.

There is also a duty to enhance and restore water bodies where possible.

In order to meet these objectives, any activity which has the potential to have an impact on any of the quality elements (biological, physio chemical, hydromorphological or chemical) must be assessed. The

Westminster LFRMS actions therefore need to be considered to ensure there are no future failures in meeting the WFD’s environmental objectives, or if any failures do occur, to ensure that they are defensible and therefore derogation would be legitimate.

The WFD also requires that any area(s) of water that is (are) designated under any other European Union directive meets the environmental requirements of that directive. This relates in particular to the

Habitats Directive, Birds Directive, Nitrates Directive and Urban Wastewater Treatment Directive.

(Previously the Freshwater Fish Directive and Shellfish Waters Directive were also relevant, but these are now superseded by the WFD.) This assessment considers the relevance of the Westminster LFRMS to such designations.

Assessment Methodology

The Environment Agency is the competent authority in England responsible for delivering the WFD. This assessment uses a methodology set out in Assessing new modifications for compliance with WFD:

detailed supplementary guidance (Environment Agency, 2010), which can be summarised for the

Westminster LFRMS as:

 Step 1: collate water body baseline data. All surface water bodies within or adjoining the

LFRMS study area have been identified. There is no underlying groundwater body. The water bodies are shown in Figure 1 at the end of this report. Water bodies were identified through examination of the Environment Agency’s on-line water body mapping resources. For each water body the following information was collated: (i) WFD water body identification and classification; (ii) relevant WFD environmental objectives; (iii) relevant WFD actions from the

Thames RBMP.

WATER FRAMEWORK DIRECTIVE COMPLIANCE ASSESSMENT

 Step 2: collate LFRMS baseline data. Details on the options appraisal process and the selection of the preferred strategic options for the LFRMS are provided in the SEA Environmental Report and are not repeated here. The LFRMS draft actions are summarised.

 Step 3: preliminary assessment. This assessment is the preliminary WFD assessment for the proposed actions to determine whether any might conflict with the WFD’s objectives.

 Step 4: design and options appraisal. This assessment identifies where WFD objectives may need to be considered during future development of any of the proposed actions in the LFRMS, including identification of any mitigation measures that might be needed at scheme development stage following adoption of the strategy.

 Step 5: detailed impact assessment. This step relates to the detailed design stage of a scheme, rather than to high level assessment of a strategy, so has not yet been undertaken.

 Step 6: Article 4.7 tests. Again, this step relates to the detailed design stage of a scheme; however, this assessment does identify whether any LFRMS proposals are likely to result in any schemes which could require such an assessment in the future.

 Step 7: reporting. This appendix to the SEA Environmental Report summarises the WFD preliminary assessment.

 Step 8: post-project appraisal work. This relates to the delivery of future schemes following adoption of the strategy.

This process is outlined in Figure 2.



Figure 2: Outline of the WFD Assessment Process

4

Water Body Baseline Data (WFD Step 1)

The only WFD water bodies partially within the City of Westminster are:



Thames Middle (i.d. GB530603911402), which is estuarine and is considered to be heavily modified by flood protection and navigation such that it does not meet the WFD target of good ecological potential; and



Part of the Grand Union Canal (Grand Union Canal, Uxbridge to Hanwell Locks, Slough Arm,

Paddington Arm, Regents Canal up i.d. GB70610078), an artificial water body that already meets the target of good potential.

Their extents within the City of Westminster are shown in Figure 1 at the end of this report.

The other significant surface water features in the City of Westminster (the Serpentine, Kensington

Gardens Lake, Regent’s Park Lake, St James Park Lake, River Westbourne, Tyburn River and Tyburn

Brook) are not identified by the Thames RBMP as water bodies in their own right.

The River Westbourne runs approximately north-south, entering the City of Westminster at

Paddington/Bayswater, passing under Hyde Park then the western edge of the study area to enter the


Thames near Chelsea Bridge. It has a small tributary, Tyburn Brook, under Hyde Park. The separate

Tyburn River runs approximately north-south further eastwards within the study area, passing under

Hyde Park and Green Park and entering the Thames near Vauxhall Bridge. There are no open stretches of the River Westbourne (which is enclosed as the “Ranelagh Sewer”) or Tyburn River (“King’s Scholars

Pond Sewer”). However, taking a precautionary approach that minor tributaries should be considered as part of the river water body into which they flow, they should be considered as part of the Thames

Middle water body.

Thames Middle GB530603911402

“Thames Middle” is a transitional water body and encompasses the tidal Thames from just upstream of

Battersea Bridge downstream to Mucking. The Westminster LFRMS is therefore relevant to only a very small part of the water body, on the left (northern) bank (see Figure 1 at the end of this report). This is considered to be a heavily modified water body (HMWB) due to coastal protection, flood protection and navigation. There are several HMWB mitigation measures in place, mostly related to navigation, but some that are not, related to flood protection (see Table 1). Because not all the mitigation measures are in place, the water body is only at moderate ecological potential, with the objective of achieving good potential by 2027. Additionally the existing combination of tidal regime and freshwater flow does not support good status in the water body.

Considering the biological quality elements, invertebrates are moderate status, macroalgae are high status and fish and plants not reported.

Considering the supporting physio-chemical quality elements, these all support high status except for dissolved inorganic nitrogen and dissolved oxygen, which both support only moderate status.

The water body has elevated levels of certain pollutants, resulting in only moderate chemical status. The pollutants in question are: specific polycyclic aromatic hydrocarbons (i.e. benzo(ghi)perylene and indeno(123-cd)pyrene which are often indicators of industrial or fossil fuel related contamination); diuron which is an agricultural herbicide; and tributyltin compounds which were used in antifouling paints but are now discontinued. Each of these is persistent in the aquatic environment.

The water body has extents that are also designated under the Birds Directive, although these are towards its downstream end far removed from the City of Westminster. It is also designated under the

Urban Wastewater Treatment Directive and the Nitrates Directive.

Table 1: Mitigation Measures for the Thames Middle Water Body

Mitigation Measure (from Thames RBMP)

Vessel Management;

Modify vessel design;

Manage disturbance;

Site selection (dredged material disposal) (e.g. avoid sensitive sites);

Sediment management;

Alter timing of dredging / disposal;

Reduce sediment resuspension;

Reduce impact of dredging;

Prepare a dredging / disposal strategy;

Avoid the need to dredge (e.g. minimise under-keel clearance; use fluid mud navigation; flow manipulation or training works)

Indirect / offsite mitigation (offsetting measures)

Operational and structural changes to locks, sluices, weirs, beach control, etc

Preserve and where possible enhance ecological value of marginal aquatic habitat, banks and riparian zone

Managed realignment of flood defence

Remove obsolete structure

In Place?

Yes

No

No

No

No

No

6



Grand Union Canal, Uxbridge to Hanwell Locks, Slough Arm, Paddington Arm,

Regents Canal up GB70610078

This is an artificial water body (navigation) that includes part of the Regents Canal at Primrose Hill and the Grand Union Canal as far west as Cowley (Uxbridge), plus the Slough and Brentwood arms of the

Grand Union Canal. Again, the Westminster LFRMS is relevant to only a very small part of the water body, where the Grand Union Canal and the Regents Canal cross the northern part of the study area (see

Figure 1 at the end of this report).

All of the morphological mitigation measures for the water body are in place; as would be expected for a canal these all relate to navigation (see Table 2). There is no biological quality data used for the water body’s assessment, but because all the identified morphological mitigation measures are in place the water body is considered to be at good ecological potential.

Chemical status does not require assessment.

The water body has extents that are also designated under the Nitrates Directive.

Table 2: Mitigation Measures for the “Canal” Water Body

Mitigation Measure (from Thames RBMP) In Place?

Manage disturbance;

Preserve and where possible enhance ecological value of marginal aquatic habitat, banks and riparian zone;

Avoid the need to dredge (e.g. minimise under-keel clearance; use fluid mud navigation; flow manipulation or training works);

Prepare a dredging / disposal strategy;

Reduce impact of dredging;

Reduce sediment resuspension;

Alter timing of dredging / disposal;

Bank rehabilitation / reprofiling;

Site selection (dredged material disposal) (e.g. avoid sensitive sites);

Awareness raising / information boards (boat wash / sources of fine sediment);

Phased de-watering and other techniques;

Selective vegetation control regime;

Appropriate vegetation control technique;

Appropriate timing (vegetation control);

Appropriate techniques (invasive species);

Modify vessel design;

Vessel Management;

Sediment management.

Westminster LFRMS Baseline Data (WFD Step 2)

Yes

Development of the LFRMS is described in the main SEA Environmental Report and that information is not repeated here. Table 3 summarises the draft actions that are the subject of this WFD assessment.

Only those measures that could physically affect the water environment (directly or as a result of implementing policies) need to be taken through the WFD assessment process and these have been identified in bold blue font .

Table 3: Westminster LFRMS Draft Actions

LFRMS 1 Actions: Tackling sources of flooding from highways

HIGH 1 Publication of most significant flood risk assets in Westminster

HIGH 2 Designation of significant flood risk assets to ensure that they are maintained.

HIGH 3 Manage and Maintain drainage assets


LFRMS 2: Tackling flood risk through planning and development

DEV 1: Provide Technical advice and promote SUDS through planning and development

DEV 2:Develop flood risk policy to manage, mitigate and adapt to flood risk

DEV 3 Review and Revise Strategic Flood Risk Assessment, as new data becomes available, or on a 6 yearly cycle, whichever is more appropriate.

DEV 4: Review and revise Local Flood Risk Management Strategy and Flood Risk Management

Plan on a 6 yearly cycle.

DEV 5- Use LFRMS to inform development of Local and Neighbourhood and development plans, drainage management and maintenance plans and programming: contingency plans and asset management plans

LFRMS 3 Tackling flood risk through Raising Awareness

AWARE 1 Modelling Surface Water Flood Risk

AWARE 2 Prepare Flood Risk Awareness Communications Plan

AWARE 3 Publish significant flood incident reports

AWARE 4 Publish significant flood risk asset register.

LFRMS 4 Tackling flood risk through Partnership working

PART 1: Work in partnership with other flood risk management authorities, stakeholders and relevant departments to address flood when it happens, and ensure contingency plans is appropriate.

PART 2: Work with Thames Water and other key stakeholders to mitigate and manage flood risk from surface water and manhole surcharge in Westminster,

Part 3 :Organise, attend and participate in flood risk management meetings such as Drain

London/LoDeg, London Central North Flood Risk Group and Westminster City Counci l’s flood risk management group

LFRMS 5:Flood Risk Management and Maintenance

RISK 1: Seek opportunities for Sustainable Drainage Systems across the city

RISK 2: Implementation of LFRMS and action plan

RISK 3 Identify and prioritise programme of flood risk management projects and funding for 2015-

2020 and provide multiple benefits in terms of biodiversity, amenity, health and wellbeing.

Preliminary Assessment (WFD Step 3)

Step 3 of the assessment process identifies which of the draft actions (of those which could physically affect the environment) are unlikely to have any impact on any WFD objectives and which could have an impact and therefore need to be taken forward for further assessment i.e. Step 4 design and options appraisal and Step 5 detailed impact assessment.

If it is determined that no deterioration will occur across any of the WFD quality elements as a result of the draft actions and that they will not prevent any water body from meeting its status or potential objectives, then no further WFD compliance assessment is required.

Figure 3 summarises the preliminary assessment process; for each action the process considers:



 The potential for hydromorphological, physio-chemical or chemical effects on any water body;

 Possible cumulative effects of a number of actions which would be inconsequential alone but may be significant in combination;

 Whether the action is associated with any habitats that are particularly sensitive or are critical to the individual biological quality elements (e.g. a fish spawning area within a river water body);



If the water body / bodies in question is / are not already at good ecological status or potential, the potential for the actions to interfere with measures that are necessary to achieve good status / potential; (these measures are detailed in the RBMP).

Assessment of each of the draft actions is presented following Figure 3, and the findings summarised in

Table 4.

Figure 3: The Preliminary Assessment Process

Tackling flood risk through highway improvements to the infrastructure or to maintenance, aims to reduce flood risk to properties and sewers.

These actions will have no impact on water body morphology unless any major new highway drainage outfall is proposed.

If improved highway drainage results in additional stormwater discharge into the combined sewer network, there is the potential for effects. Flow changes could for example increase the risk of manhole surcharge. There may also be changes in water quality for example if highway runoff is poor quality, or if drainage improvements incorporate some runoff treatment. Overall however, combined with reduced pressure on the sewer network, these actions imply a beneficial reduced risk of combined surface water and foul sewage discharge. These actions will not prevent any of the WFD mitigation measures

8 WATER FRAMEWORK DIRECTIVE COMPLIANCE ASSESSMENT

identified for the Lower Thames water body (see Table 1) from being delivered. They are not relevant to any of the other Directives that apply to either water body.

Conclusion of preliminary assessment: Actions HIGH3 and HIGH4 will need future consideration during site-specific design to determine whether the proposed drainage improvements will result in any significant changes in the quantity and/or quality of highway discharges to any water body. This consideration should include the potential effects combined across the highway network as a whole, and any site-specific sensitivities within the water bodies involved.

Tackling Flood Risk through Development Planning (Actions DEV1- DEV6)

Actions DEV1 to DEV6 will promote and require greater use of sustainable drainage techniques (SUDS) at development sites.

These actions will have no impact on water body morphology unless any major new SUDS schemes constructed, in which case any affect is likely to be beneficial for example by improving riparian habitat diversity.

Since it is very unlikely that there will be any significant greenfield development sites within the City of

Westminster, application of SUDS should always result in improvement of runoff rates and runoff water quality compared to a pre-SUDS position. Combining SUDS with green/bluespace could provide additional wetland habitat which, depending on the location of the development, could be associated with one of the water bodies (or surface water tributaries if the proposed SUDS were to entail any deculverting).

These actions will not prevent any of the WFD mitigation measures identified for the Lower Thames water body (see Table 1) from being delivered. If there are any major development SUDS alongside the

Lower Thames this presents an opportunity to directly contribute to mitigation measures, by enhancing the ecological value of the riparian zone or allowing managed realignment of existing flood defences.

The actions are unlikely to be relevant to the canals water body. They are not relevant to any of the other Directives that apply to either water body.

Conclusion of preliminary assessment: Actions DEV1 to DEV6 will comply with the environmental objectives of the WFD and have the potential to directly support delivery of some of the morphological mitigation measures for the Thames Middle water body or its tributaries.

Tackling Flood Risk through Partnership Working (Actions PART1 to PART3)

These actions will result in greater attention by riparian owners and other stakeholders to their responsibilities related to flood defence, and the delivery of related partnership projects

PART1- PART 3 will have no impact on water bodies, but presents an opportunity to promote the WFD environmental objectives alongside other responsibilities of the stakeholders, which could result in future beneficial contributions to the objectives.

Since the schemes delivered in relation to PART3 are not specified, it cannot be stated at this stage whether or not there could be effects on any water body. However, they are not relevant to any of the other Directives that apply to either water body.

Conclusion of preliminary assessment: Action PART1-PART 2 requires no further assessment but any schemes delivered in relation to PART 3 will need future consideration during site-specific design to determine their implications for any water body, including combined effects and site-specific sensitivities.



Flood Risk Management and Maintenance (Action RISK1 to RISK 3)

Action RISK1 to seek opportunities for sustainable drainage systems to management flood risk supports the principles of Making Space for Water, the cross Government programme for developing strategy for flood and coastal erosion risk management in England. It is also potentially aligned to actions related to delivering improved SUDS in the City of Westminster. SUDs can support flood risk management by:

• Providing dedicated flood water storage areas (with potential for new wetland habitat);

• Reducing the rate at which rainfall runs off land and buildings;

• Supporting a more natural and slower surface water response to heavy rainfall, which might include channel restoration and deculverting watercourses.

RISK4 is not relevant to any of the other Directives that apply to either water body.

Conclusion of preliminary assessment: Action RISK4 will comply with the environmental objectives of the WFD and has the potential to directly support delivery of some of the morphological mitigation measures for the Thames Middle water body or its tributaries.

Table 4: Preliminary WFD Assessment of LFRMS Draft Actions

Actions

Tackling flood risk through highways management

Tackling Flood

Risk through

Development

Planning

Relevant

Water

Body

Depends on location

Depends on location

Affects

Morphology?

No

Possible benefit – investigate on site-bysite basis

No

Affects

Flow?

Possible – investigate on site-bysite basis

Affects

Water

Quality?



Possible benefit - investigate on site-bysite basis

No No

Cumulative

Effects

Possible – investigate at highway network scale

Possible benefit - investigate as sites come forward

No Tackling Flood

Risk through improved understanding and raising awareness

Tackling flood risk through partnership working

None

Depends on location




Possible – investigate as schemes developed

Affects

Sensitive

Areas?

Possible - investigate on site-bysite basis

Affects

Mitigation

Measures?

No


Possible contribution

–investigate on site-bysite basis

No No



Flood Risk

Management and

Maintenance

Depends on location




Possible benefit - investigate as schemes come forward


Possible contribution

–investigate on site-bysite basis

Uncertainty

It is difficult to assess the potential impacts from a number of the draft LFRMS actions because they do not identify individual schemes but rather they will identify, encourage or develop such schemes. These will require WFD compliance screening assessment if located within or adjacent to a water body

10 WATER FRAMEWORK DIRECTIVE COMPLIANCE ASSESSMENT

(including any tributary water course) or IF significantly changing the discharge to a water body. The relevant LFRMS actions have been identified in Table 4.

Construction Phase Effects

It is possible that during the delivery of any scheme which are within or adjacent to a water body that there may be localised habitat and water quality impacts as a result of the works. However, assuming that any impacts would be minimised through the use of sensitive construction techniques and compliance with the Environment Agency’s Pollution Prevention Guidelines such impacts are highly unlikely to cause a permanent change in the status / potential of any of the water bodies.

5. Conclusion

It is concluded that overall the draft actions in the Westminster LFRMS are unlikely to have any significant adverse impacts on any water bodies. Given the current level of detail on specific actions no detailed WFD compliance assessment is required at this stage, and no Article 4.7 assessment

(derogation) is required.

Some of the draft actions in the LFRMS may give rise to schemes or physical interventions that themselves could require WFD compliance screening assessment; these are:



Highways Drainage Improvement Schemes (HIGH 3)



Partnership schemes PART2;

Some of the draft actions will promote schemes or physical interventions that could make positive contributions towards WFD environmental objectives; these are:



Highways drainage improvements HIGH1



Planning and Development DEV1;



Partnership schemes PART2;



SUDS RISK 1

These requirements for future assessment, and opportunities for positive contributions, will depend on the location and scale of the proposed physical interventions.

Figure 1: Water Bodies Relevant to the Westminster LFRMS

Water Body Baseline Data (WFD Step 1)

Appendix D

Water Framework Directive Assessment

Water Framework Directive Compliance

Assessment

The Water Framework Directive

Background

WFD Environmental Objectives

Assessment Methodology