Policy paper

River basin planning guide to alternative objectives: Solway Tweed River Basin Management Plan

Updated 1 January 2024

Applies to England and Scotland

In specific circumstances (set out in the Water Framework Directive (WFD) Regulations) deviation from achieving the default water body status objectives is allowed. Objectives which are different from the default objectives are referred to as alternative objectives.

The alternative objectives and their conditions are the only relevant considerations when justifying the prioritisation of action under the WFD Regulations.

The types of alternative objective are:

• an extended deadline (for example, achieving good status by 2027)
• a less stringent objective (for example, achieving moderate status by 2015)

Reasons for setting alternative objectives

The justifications or reasons that can be used for setting alternative objectives are as follows.

Technically infeasible - no known technical solution is available

This applies where there is no practical technique for making the necessary improvement. It does not include financial considerations. Techniques which may be under development but are not yet known to be effective in practice will fall into this category.

Technically infeasible - cause of adverse impact unknown

This applies where a water body is classed as worse than good but the reason (the pressure or the specific source of the pressure) for this failure has not yet been determined. This may signal the need for an investigation or may reflect genuine scientific uncertainty. Consequently, a solution cannot feasibly be identified.

Technically infeasible - practical constraints of a technical nature prevent implementation of the measure by an earlier deadline

This includes administrative constraints in terms of commissioning, gaining permission for, and undertaking the necessary works. Does not include constraints due to a lack of legislative mechanisms or of funding.

Technically infeasible - problem cannot be addressed because of lack of action by other countries

The application of this exemption is expected to be very limited in the UK. It may possibly be applicable where problems are caused by aerial deposition of transboundary pollutants and (a) local mitigation cannot solve the problem; and (b) discussions with the other countries have not led to effective action.

Disproportionately expensive - unfavourable balance of costs and benefits

In this case attaining the default objective is not justified because the costs of the measures exceed the benefits, taking into account qualitative as well as quantitative information.

Disproportionately expensive - disproportionate burdens

This applies where the measure would be unaffordable to implement within a particular timetable without creating disproportionate burdens for particular sectors or parts of society; or the only solution would be significantly at odds with the polluter pays principle.

Natural conditions - ecological recovery time

Applies where there is expected to be a delay before the biological quality of the water body recovers. The delay may be due to the time taken for the plants and animals to re-colonise and become established after the hydromorphological, chemical and physicochemical conditions have been restored to ‘good’; or the time taken for the habitat conditions to stabilise after improvement works.

Natural conditions - groundwater status recovery time

Applies where the climatic or geological characteristics dictate the rate at which groundwater levels recover or saline (or other) intrusions reverse once over-abstraction has been addressed.

Natural conditions - chemical status recovery time

Applies where there is expected to be a delay in the chemical substance meeting the required standard once the necessary measures to achieve compliance have been implemented.

Alternative objectives for European site protected areas

In previous cycles of river basin planning, deadlines for achievement of the objectives for some European site protected areas have been extended for a range of reasons.

The plans must aim to achieve the objectives for all the remaining European site protected areas by 2027; less stringent objectives cannot be applied. Ecological recovery time can be used as a reason for extended deadlines beyond 2027 when all the required measures have been implemented.

The specific reasons for extended deadlines for each European site protected area are provided in a spreadsheet. You can access this spreadsheet on the Water Environment Hub.

Circumstances for setting alternative objectives

This section describes the circumstances in which alternative objectives have been set for water bodies and some European sites protected areas under regulations 16 and 17 of the WFD Regulations. The general circumstances in which each reason has been applied are described with, where relevant, more specific circumstances for particular elements. All the specific circumstances may not apply in the English part of the Solway Tweed River Basin District.

Technically infeasible: no known technical solution is available

General approach

This reason has been used to justify setting less stringent objectives for water bodies under regulation 17. It has also been used to justify extending the deadline for achieving good chemical status for some substances under regulation 16, and in a limited number of cases it has been used to justify extending the deadline for achieving protected area objectives.

As well as being applied where there is no known practical technique for making the necessary improvement, this reason has also been used in cases where:

• techniques are under development but are not yet known to be effective in practice

• there is a known technical solution, but that solution cannot be applied in a specific location due to specific local conditions

Biological elements

Invasive non-native species (INNS) may impact upon biological elements resulting in them being at less than good status.

Invasive non-native species (INNS) may impact upon biological elements resulting in them being at less than good status. For many established INNS, such as American signal crayfish, there is no known technical solution to eradicate them. In these circumstances a less stringent objective is set for the impacted biological element under regulation 17, provided that the water body is not also a European site protected area (see the section named ‘Biological elements - European site protected areas’).

Biological elements and hydrological regime

Flows in some rivers and streams can vary naturally on a seasonal basis (for example ephemeral streams and winterbournes) or due to features like swallow holes. These natural phenomena can result in a water body being classified at less than good status. In these instances, there is no technical solution to the failure to reach good status and a less stringent objective is set under regulation 17.

Fish

Natural barriers to fish migration sometimes result in fish being classified at less than good status in a water body. In these situations, there is no technical solution to the fish failure since natural barriers do not require removal or easement and a less stringent objective is set under regulation 17.

The natural physical characteristics of a water body may be unsuitable for certain fish species which, although expected to be present by the fish classification tools, are in fact absent, resulting in fish being reported at less than good status. There is no technical solution in these circumstances since the absence is due to the natural characteristics of the water body and therefore a less stringent objective is set under regulation 17.

Groundwater quantity

In some areas public water supply is mainly by abstraction from groundwater. Although the groundwater may be at poor quantitative status as a result of the abstraction it may not be technically possible to transfer the abstraction to another groundwater body, surface waters or an area of low environmental sensitivity. In such cases a less stringent objective has been set under regulation 17.

This exemption has been used when the environmental and socioeconomic needs served by the supply of public water cannot be achieved by other means which are a significantly better environmental option not entailing disproportionate costs, as required by regulation 17(2).

Groundwater chemical

There is not always a technical solution to improve a groundwater body to good chemical status where:

• there are multiple small diffuse discharges from abandoned mines stretching across a groundwater body which are causing it to be at poor status. These discharges can be so numerous that it is technically infeasible to put in place measures to improve all the discharges to get to good chemical status

• a large mining discharge is in a highly constrained location, such as in the middle of a village, and land is not available for treatment schemes. In these circumstances a less stringent objective has been set under regulation 17

Phosphate, phytobenthos and macrophytes

In England, it is generally currently considered to be technically infeasible to build a sewage treatment works that will reduce phosphate in discharges to less than 0.25mg/l.

If a water body requires discharges of less than 0.25mg/l phosphate to achieve good status, then this reason has been used to justify a less stringent objective under regulation 17.

Where nutrient targets required to meet European site protected area objectives are beyond technically achievable limits then this reason has been used to justify an extended deadline to achieve the objective under regulation 16. The exemptions apply to the phosphate and the impacted biological elements such as phytobenthos and macrophytes.

This exemption has been used when the environmental and socioeconomic needs served by the sewage treatment works to dispose of sewage cannot be achieved by other means which are a significantly better environmental option not entailing disproportionate costs, as required by regulation 17(2).

Biological elements - European site protected areas

The control or eradication of INNS is required on many European site protected areas. For some INNS control methods are not yet available but may become available following further research. Timescales for achieving European site protected area objectives where INNS are involved are therefore often over a very long term and dependent on the success of future research.

In these circumstances the deadlines for achieving European site objectives have been extended under regulation 16.

Nutrients - European site protected areas

Some European site lake water bodies are impacted by eutrophication. In addition to reducing phosphate inputs from diffuse or point sources, in-lake measures may also be needed to reduce internal cycling of nutrients and reduce re-suspension of sediments.

For some lakes the in-lake measures would require the removal of nutrient rich sediment. Depending on the site, the removal and disposal of nutrient rich sediments is considered technically infeasible.

In these circumstances when there is no known technical solution the deadline for achieving the European site objectives have been extended under regulation 16.

Technically infeasible: cause of adverse impact unknown

General approach

This reason has been used to justify setting extended deadlines for achieving objectives for water bodies and some protected areas under regulation 16.

It has been applied when a water body is at less than good status and the evidence is insufficient to identify the reason or reasons for not achieving good status with the required level of certainty to support identification of the measures needed to improve status.

This exemption has been used where:

• genuine scientific uncertainty remains despite investigation work having been carried out

• there has been insufficient time to complete the necessary investigation work since the water body was classified at less than good status

An investigation in this context includes desk studies drawing on existing data and knowledge about the water body and wider catchment, engagement and consultation with catchment partners and bespoke field investigations.

Metals

Some groundwater bodies are at poor status because of polluted mine waters entering the groundwater. Whilst it is known that abandoned mines are the general source of the metals more investigations are needed to determine exactly where the metals are coming from so that the necessary measures can be identified and appraised.

In these circumstances an extended deadline for achieving good status has been set under regulation 16.

Sediment and nutrients - European site protected areas

Nutrient enrichment of European sites can be complex to understand and address and although understanding has improved there are still some sites that will require further investigation to identify the precise causes or sources before solutions can be identified.

In these circumstances an extended deadline for achieving European site protected area objectives has been set under regulation 16.

Technically infeasible: practical constraints of a technical nature prevent implementation of the measure by an earlier deadline

General approach

This reason has been used to justify setting extended deadlines for achieving objectives for water bodies and some protected areas under regulation 16.

In some cases, although the appropriate measures to achieve the water body or European site objectives have been identified, there are constraints on commissioning and undertaking the necessary works that will extend the time taken to achieve the objectives.

This exemption has only been applied where there is confidence (a reasonable expectation) that the implementation of the measures necessary to achieve the objectives will start by 2027, that is, the appropriate measure has been identified, funding has been agreed and there is a mechanism in place to deliver it and work will start during this cycle of river basin management planning.

Hydrological regime

Some water company schemes are large and complex, for example building a new reservoir, and so installation will happen over an extended timescale. A water company measure may have been programmed for implementation during cycle 2, but the measure will not be delivered until after 2021 because it involves the installation of a large complex scheme.

In these circumstances an extended deadline of good by 2027 has set under regulation 16.

Total phosphorus (lakes)

Physical habitat restoration in lakes can be complex, large-scale and often involves more than one organisation. It often requires significant work to secure stakeholder consensus and cooperation. Actions may need to happen in a specific order to be effective, such as tackling diffuse sources of pollution before carrying out physical restoration works to the lake. Implementation of lake restoration action plans may therefore take place over several years.

In these circumstances an extended deadline for achieving good status has been set under regulation 16.

Hydrological regime - European site protected areas

Physical habitat restoration in rivers and lakes can be complex, large-scale, and often takes place over several years. It often requires significant work to secure stakeholder consensus and cooperation. In some cases, particularly river restoration, it can be detrimental to carry out all of the works required to restore hydrology over a short time period as this can result in damaging ecological disturbance to the majority of a protected area river length.

This exemption has been used for sites that have unfavourable river and lake hydromorphology, unfavourable water levels on wetland and over abstraction. The necessary measures can be technically very complex and the planning, commissioning and delivery of the necessary actions to address these aspects of European site condition will require continued effort over long time scales. In these circumstances extended deadlines for achieving the European site protected area objectives have been set under regulation 16.

Physical modifications - European site protected areas

In some locations changes to coastal and estuary morphology are impacting on European site protected area objectives. The measures needed to address these pressures can be technically complex, involving large scale engineering works which take a long time to implement.

In these circumstances extended deadlines for achieving the European site protected area objectives have been set under regulation 16.

Disproportionately expensive: unfavourable balance of costs and benefits

General approach

This reason has been used to justify setting less stringent objectives for water bodies under regulation 17.

This exemption has been used in situations where:

• there is no environmental problem to solve and therefore the costs of taking any action would exceed the benefits.

• although water body classification tools and the monitoring programme represent best science, due to the varied nature of the environment they sometimes flag a problem where no problem exists. Additional information including risk assessments and information from third parties can be used to establish if there is an environmental problem

• economic appraisal has determined that the costs of implementing the most cost effective and technically feasible measures needed to reach good status are greater than the benefits to be gained from achieving good status

In some cases, although a less stringent objective has been set action will still happen to improve the water body to the best possible status, as required by regulation 17(3) and (4). Measures will be implemented up to the point where doing more would be disproportionately expensive. In these cases, pressures may be partially resolved or, where there are multiple sources in a catchment, some may be addressed whilst others are not.

Fish

In some cases, the fish classification tool gives a result of less than good status due to the absence of a certain species, but it is known from other data, such as angling match records, that the species is both present and at expected densities in the water body. Therefore, there is no environmental problem to solve and action to take.

In these circumstances a less stringent objective has been set under regulation 17.

Hydrological regime

In some water bodies there are multiple small abstractions or a large abstraction from either groundwater or surface water, or a combination of the two, which is affecting surface water flows. The potential compensation costs of changing abstractions, either the abstraction regime or decreasing abstraction volumes overall, can be disproportionately expensive.

In these circumstances a less stringent objective has been set under regulation 17.

This exemption has been used when the environmental and socioeconomic needs served by the supply of public water cannot be achieved by other means which are a significantly better environmental option not entailing disproportionate costs, as required by regulation 17(2).

Fish, invertebrates, mitigation measures assessment

The costs of implementing some mitigation measures to address pressures from physical modifications are very high and disproportionately expensive. For example, in urban areas where improvement works are often technically and spatially challenging there are increased costs for ground works and securing land availability as well as spatial limitations.

In these circumstances a less stringent objective has been set under regulation 17. The exemption applies to the Mitigation Measures Assessment and the impacted biological elements.

This exemption has been used when the environmental and socioeconomic needs served by the physical modifications cannot be achieved by other means which are a significantly better environmental option not entailing disproportionate costs, as required by regulation 17(2).

Groundwater quantitative

The groundwater body is at poor status but the groundwater is a confined aquifer that has no direct or indirect link to environmental features or problems.

In these circumstances a less stringent objective has been set under regulation 17.

Groundwater chemical

In some groundwater bodies which are failing the General Chemical Test for nitrates, farming would need to stop across a very wide area of land in order to meet the good status objective. The costs of implementing such measures have been judged to exceed the benefits and therefore disproportionately expensive.

In these circumstances a less stringent objective has been set under regulation 17.

Phosphorus, ammonia, dissolved oxygen, macrophytes, phytobenthos

Engineering measures and technologies to improve water quality of discharges from sewage treatment works can have high costs relative to other measures within a catchment bundle of measures. Although these measures can be technically feasible, the cost of implementation can exceed the benefits to be gained from achieving good status. This is especially true in cases where improvements are limited to an individual water body which limits the overall relative benefit in the catchment.

In these circumstances a less stringent objective has been set under regulation 17.

This exemption has been used when the environmental and socioeconomic needs served by the sewage treatment works to dispose of sewage cannot be achieved by other means which are a significantly better environmental option not entailing disproportionate costs, as required by regulation 17(2).

Nutrients

For phosphate failures in freshwater and dissolved inorganic nitrogen in estuaries and coastal waters, targeted regulatory measures (for example, water industry nutrient removal schemes) require sufficient evidence of an eutrophication problem to justify the measure. If a water industry sewage works is a major source of relevant nutrients, and nutrient removal would be required to improve status to good but there is insufficient evidence of biological eutrophication impacts within the downstream water body or catchment, then there is no ecological problem to solve and the costs of taking action would exceed the benefits.

In these circumstances a less stringent objective has been set under regulation 17.

Less certainty of eutrophication does not preclude consideration of non-regulatory or voluntary approaches to address other nutrient sources.

Hydrological regime

If the hydrological regime is classified as not supporting good status but investigations have not shown any evidence of impacts upon biological elements, then there is no environmental problem to solve and the costs of taking action would exceed the benefits.

In these circumstances a less stringent objective has been set under regulation 17.

Metals

The cost of mine remediation measures are often relatively high within a catchment bundle of measures and in some cases, where the extent of the benefits are less certain and limited to specific water bodies, the cost of implementation exceeds the benefits.

In these circumstances a less stringent objective has been set under regulation 17.

Physico-chemical elements, chemicals

The complex nature of pressures and pollutant pathways in urban areas along with spatial challenges mean that the costs of implementing successful and worthwhile sustainable urban drainage measures can be high. These costs can exceed the benefits, especially if the benefits are limited to specific, small urban water bodies.

In these circumstances a less stringent objective has been set under regulation 17.

Disproportionately expensive: disproportionate burdens

General approach

This reason has been used to justify setting extended deadlines for achieving objectives for water bodies and some protected areas under regulation 16 for the purposes of phased achievement of the objectives.

This reason has been used in 2 situations:

• where funding for measures was not confirmed, it is assumed that the measures were therefore unaffordable to implement before 2027 without creating a disproportionate burden on the relevant sector or fell outside government spending limits

• in these circumstances an extended deadline for achieving the objectives has been set under regulation 16.

• in some cases, although the measures were funded there was uncertainty about:

  • exactly which measures will take place and where they were implemented, for example, where implementation of measures was voluntary

  • the element-level improvements in status that will be achieved by the measures

It is assumed that a different approach to implementing the measures could not be taken without placing a disproportionate burden on the relevant sector. In these circumstances an extended deadline for achieving the objectives has been set under regulation 16.

Natural conditions: ecological recovery time

General approach

This reason has been used to justify setting extended deadlines for achieving water body objectives under regulation 16.

Generally speaking the ecology of aquatic systems recovers quickly when pressures are removed. However, in some cases there may be a delay before the biological quality of the water body recovers.

The delay may be due to the time taken for the plants and animals to re-colonise and become established after the hydromorphological, chemical or physicochemical conditions have been restored or the time taken for the habitat conditions to stabilise after improvement works.

The natural recovery of biological populations is typically achieved through re-colonisation. Where impacted habitats are hydrologically connected to un-impacted locations, recovery can occur quickly. This is particularly true for species that show mobility through their life history (for example, fish and invertebrates). Here, recovery can happen within a limited number of generations and therefore years. Where habitats lack this connectivity, or where species are no longer present, recovery may take much longer.

Other circumstances where ecological recovery time may be delayed are as follows.

Measures to remove the activity giving rise to a pressure are successful, but the pressure takes time to reduce. Here the ecology cannot recover quickly as it is still impacted by a pressure, albeit reducing in magnitude. Recovery of ecosystems from prolonged exposure to increased nutrients provides a good example. In such cases it may take tens of years for the plant communities to return to those expected under near reference conditions once all improvement measures are implemented. In such cases deadlines can be extended beyond 2027.

Measures to remove pressures are successful, but the ecology does not return to the community expected to be seen under near reference conditions. Instead, the ecology assumes a different ecological stable state. In these cases, further management of the ecosystem may be needed to trigger a change back to good status.

Ecological recovery time is only used as a justification for an extended deadline if there is confidence that the measures necessary to achieve the improvement in status will be implemented by 2027.

In these circumstances an extended deadline for achieving the objectives has been set under regulation 16.

European site protected areas

The deadlines for achieving the objectives for European site protected areas can be extended, including extensions beyond 2027, when the measures are in place, but it will take time for favourable condition to be achieved.

Natural conditions: groundwater status recovery time

General approach

This reason has been used to justify setting extended deadlines for achieving water body objectives under regulation 16.

Groundwater bodies can take many decades to recover from chemical pressures once measures to reduce the pressures are in place. This is mainly because of the delay as water travels downwards through the unsaturated zone to the water table. The length of this delay will depend on many factors including the rate of recharge, properties of the pollutant and the nature of the hydrogeological setting.

The recovery time delay can vary between several years to many decades. In the majority of cases where this exemption has been used the substance causing poor status was nitrate. Groundwater status recovery time has mainly been used for groundwater chemical pressures.

In these circumstances an extended deadline for achieving the objectives has been set under regulation 16.

Dissolved inorganic nitrogen

In some cases nitrates from groundwater bodies are leaching into surface water bodies such as estuaries resulting in dissolved inorganic nitrogen failures. As nitrate can take a long time to move through groundwater, it will correspondingly take a long time for the surface water to recover.

In these circumstances an extended deadline for achieving the objectives has been set under regulation 16.

Natural conditions: chemical status recovery time

General approach

Persistent, bioaccumulative and toxic (PBT) substances can be found for decades in the water environment at levels exceeding the biota environmental quality standard, even when measures to reduce or eliminate the emissions of these substances are already in place.

Mercury and its compounds and polybrominated diphenylethers are PBT substances where national and international measures to achieve good status are in place. To account for the long recovery time once measures are in place for these substances the objective deadline has been extended under regulation 16.