Drought plans: environmental assessment and monitoring

The environmental assessments, monitoring and mitigation or compensation measures you need to consider as part of a water company drought plan.

This guidance was withdrawn on

Go to Drought: managing water supply which explains what water companies are expected to include in their drought plans and how customers can comment on the plans.

If you’re writing a drought plan you’ll need to include:

You’ll also need to consider whether individual drought actions, groups of drought actions within your plan or your overall plan require:

How to write an environmental assessment

Your environmental assessment must include details of any changes as a result of your actions to:

  • water flow or level regimes
  • water quality
  • ecology (sensitive features, habitats and species)
  • designated sites (habitats and species)
  • fish populations (in particular migratory fish)

You must also include an assessment of the effect that your plan will have on Water Framework Directive (WFD) status or potential and consider the effects your actions might have on environmental objectives and measures set out in river basin management plans (RBMPs). Contact the Environment Agency (and if relevant Natural Resources Wales) if you’re unsure about the WFD assessment required for your plan or need more information on the objectives or measures set out in the RBMPs.

Your environmental assessment should also set out whether you’ll do anything to lessen the impact of your actions on these features and if so what.

Where more than one action could have a combined effect on the environment you should consider their effects together, for example a group of licences in a particular habitat or designated site. You should also consider the effects your actions will have on other water users.

The level of detail included in your environmental assessment should be based on the level of risk posed by the action you’re assessing, for example based on the scale of the impact, the expected frequency of use or the importance or sensitivity of the site.

You should use the ‘Handbook for scoping projects: environmental assessment’ and the EcIA guidelines to carry out your assessment.

Set out the results of your environmental assessment in a table like this.

Assessment Action 1 Action 2
Action to maintain water supply    
Risk to the environment (high, medium, low or unknown) and how you’ve assessed this    
Summary of likely environmental effects (include details for features of moderate and major sensitivity, and minor sensitivity features from designated sites). Assess the likely impact on WFD ecological and chemical status    
Information used to understand conditions before drought or any drought actions are implemented    
A summary of additional baseline monitoring requirements before your application    
Mitigation and compensation measures    
Effects on other activities, for example fisheries or industry    

Carry out an environmental assessment

Your environmental assessment should:

  • assess the hydrological or hydrogeological effects of your actions
  • assess the environmental sensitivity of the affected areas
  • identify any further evidence needed

Assess hydrological or hydrogeological effects

You must demonstrate that you understand the effect your actions will have on the hydrology or hydrogeology of every river reach, wetland or lake area that they influence. You should:

  • identify conditions which trigger your actions
  • identify any changes that your actions are likely to bring about, specifying their length and severity
  • describe the likely conditions if you don’t carry out your actions
  • identify the extent of the area affected by your planned actions

Assess environmental sensitivity and impact

You must assess the sensitivity of the habitats and species that are present in each reach or area affected by your actions. You should consider:

  • their sensitivity to any hydrological or hydrogeological changes your actions are likely to cause, for example habitat loss due to level change or degradation of the habitat due to changes in dissolved oxygen content or temperature
  • the extent to which your actions will affect the current WFD status for water bodies - refer to the current UK Technical Guidance Group method statements to ensure you’re using the correct assessment methods and tools
  • the risk of your actions spreading invasive non-native species
  • if your actions will affect any measures proposed in RBMPs
  • the sensitivity of designated sites to your actions
  • potential for cumulative effects, for example when combined with other actions in your plan or other abstractions likely to be taking place in that reach or area

You must support your assessment using monitoring data and appropriate tools for analysing and interpreting the data, such as:

  • environmental sensitivity, for example if you need more information about a feature
  • existing data, assessments, plans and other knowledge that may be relevant to the assessment
  • whether your actions could have an effect on the movement of migratory fish
  • uncertainties relating to the assessment and what is required from you

Each assessment needs expert judgement; you’ll need more expert judgement where you have less data.

Identify any further evidence needed

You must identify if there are any gaps in your understanding that you can fill by collecting more information. If there are then it’s your responsibility to collect this information.

When you need to carry out environmental monitoring

You must carry out further environmental monitoring if:

  • you don’t have enough data to carry out an environmental assessment
  • your actions present a significant risk to protected habitats, species or designated sites and there isn’t enough monitoring in place to assess it

Environmental monitoring data supports:

  • the overall drought plan, including its environmental assessment and setting of drought triggers
  • environmental assessment of actions within a plan
  • an environmental statement for an action, for example a drought permit or order

You should plan to collect adequate data about the normal conditions at any sites your actions might adversely affect. You should do this as soon as is practical after the publication of your plan. Normal conditions are the conditions at the site that exist when a drought is not taking place or about to happen. This is when you’re not undertaking any drought actions or mitigation at the site. During a drought you may implement or increase frequency of hydrological, chemical or physicochemical monitoring providing you’ve made it clear why you’re doing this.

If you need to carry out further monitoring you’ll need to make an environmental monitoring plan.

What to include in an environmental monitoring plan

Your environmental monitoring plan sets out all the monitoring you’ll need to do for your drought plan. It should set out:

  • how you’ll use new monitoring data to fill gaps in your understanding of:
    • the environmental sensitivity of a site and the damage your actions may cause
    • the normal conditions at a site
    • the recovery of the environment after drought
  • how you’ll assess the effects of your actions during and after a drought

You can use data from sites that are subject to ongoing monitoring by the Environment Agency or Natural Resources Wales for other purposes, such as the WFD. However there’s no guarantee of the long-term availability of this data. When you update your drought plan you must check with the Environment Agency (and if relevant Natural Resources Wales) for changes to the availability of data that you may use. You must alter your monitoring plans accordingly.

You should also consider other potential sources of historic monitoring data such as county wildlife trusts, biological records centres and managers of relevant areas, such designated sites.

The amount of work carried out should be in proportion to the environmental risk posed. This will be determined by the sensitivity of the environment, the likelihood of the action (or combination of actions) and its consequent severity.

Write your environmental monitoring plan

You should present your environmental monitoring plan in a separate document alongside the environmental assessment.

You should discuss your plan as early as possible with the Environment Agency and, if appropriate, Natural Resources Wales and Natural England. They will be able to advise you on:

  • availability of their historical monitoring data and ongoing monitoring programmes
  • their understanding of the hydrology, hydrogeology, habitats and species at sites likely to be affected by your actions
  • information on WFD status and programmes of measures
  • environmental sensitivity of sites and areas
  • the design of your monitoring plan

When to carry out HRAs

You must carry out a HRA under the Conservation of Habitats and Species Regulations 2010 if any actions are likely to have a significant effect on European sites such as:

  • disturbing species or habitat
  • damaging the size, structure or reproductive abilities of a species’ population
  • reducing the area’s resilience against man-made or natural changes

The European sites are:

  • special areas of conservation
  • special protection areas
  • Ramsar sites

A HRA will identify whether or not your actions will have an adverse effect on a site’s integrity.

If you need to carry out a HRA, you should consult Natural England and the Environment Agency or Natural Resources Wales before you prepare your draft drought plan.

To carry out a HRA, use the UK Water Industry Research (UKWIR) report ‘Strategic environmental assessment and habitats regulations assessment’.

When to carry out SEAs

You may need to carry out a SEA of your plan if the actions in it are likely to have a significant effect on the environment.

To find out if you need to carry out an SEA, use information from the HRA process. This guidance will help:

You should let the Environment Agency know if you need a SEA before you prepare your draft drought plan.

If you do need a SEA you must follow the practical guidance on carrying it out. Include a report on the likely significant environmental effects of your actions and the reasonable alternatives to them.

Set out your mitigation and compensation measures

Your drought plan must set out everything you’ll do to:

  • mitigate or reduce adverse effects that your actions have on the environment
  • provide compensation for adverse effects that remain after you’ve taken measures to mitigate them

From your environmental assessment, you can identify the effects of your proposed actions on the environment. Then you can identify where you may need to carry out activities to mitigate adverse effects.

In your drought plan you must identify:

  • before drought mitigation actions
  • during drought mitigation actions
  • after drought mitigation actions

As a drought develops it is important to review your planned mitigation measures before implementing them as each drought is unique.

Discuss your proposed mitigation or compensation activities with the Environment Agency or Natural Resources Wales and any other affected parties. Your drought plan should also include details of any additional permits or approvals you need to carry out these activities.


You can contact the Environment Agency (and if relevant Natural Resources Wales) if you’re unsure about any aspect of the planning process and need further advice.

Environment Agency
National Customer Contact Centre
PO Box 544
S60 1BY

Telephone: 03708 506 506*


Natural Resources Wales
c/o Customer Care Centre
Ty Cambria
29 Newport Road
CF24 0TP

Telephone: 0300 065 3000*


Natural England
Block B
Government Buildings
Whittington Road

Telephone: 0300 060 3900*


*call charges apply

Published 20 July 2015
Last updated 8 December 2015 + show all updates
  1. Changes include: asking companies to look at a range of drought events, including a strong recommendation to consider plausible droughts beyond the worst drought on record and explain why if they haven’t; asking companies to consider the necessity for resilience options for events beyond what their supply system is capable of; clarification of our expectations for environmental assessment, mitigation and compensation (particularly with reference to what should happen at each stage ie before, during and after a drought); clarification of our expectations for companies to supply information on proposed drought permits and orders; clarification of what we expect in a monitoring plan; addition or update of links to the latest research or resources; other changes to update wording or references for clarity or to reflect policy and legislative change (ie move from 3.5 year cycle to 5 year cycle).

  2. First published.