Water neutrality and planning applications
Last updated: 13 April 2022 (click the blue box below to see updated sections)
The following content was added or updated on 13 April 2022. Click the question titles to scroll to the particular question.
This page is for anyone considering applying for development in the Horsham District.
On this page you'll find FAQs from Natural England for development within the Sussex North Water Zone and an explanation of Horsham District Council’s proposed method of dealing with the issue.
These FAQs are specific to information needed to support a planning application. They should be read alongside our Water neutrality and Planning Policy page.
Natural England FAQs
On 2 March 2022 Natural England has updated the answers to to frequently asked questions (FAQs) for developers in considering their Position Statement when applying for development in Sussex North.
Horsham District Council FAQs
The following questions outline are directed towards anyone considering applying for development in the Horsham District, and explain Horsham District Council’s proposed method of dealing with the issue. This page will be updated periodically as matters evolve and change.
This document should be read in conjunction with the accompanying Local Plan Water Neutrality FAQs, the Natural England (NE) Position Statement (September 2021), and the Natural England FAQ’s (December 2021) for development within the Sussex North Water Supply Zone.
What types of application are impacted by the Natural England Position Statement?
All development proposals that consume mains water are potentially impacted by the Natural England Position Statement. Horsham District Council has though screened out all householder planning applications (with the exception of those proposals for annex accommodation and swimming pools), and all development granted under Schedule 2 Parts 1 and 2 of the General Permitted Development Order from having a likely significant impact on the Arun Valley, as there is no evidence that extensions or minor alterations to dwellings will directly result in an increase in water consumption.
All other development proposals that consume mains water are now required to demonstrate water neutrality. This includes all development other than that mentioned above granted under the General Permitted Development Order- see below for further details on this. All applications for Reserved Matters must also now demonstrate water neutrality. Applications made under s.73 of the Town and Country Planning Act must consider water neutrality- this is discussed in more detail below.
Applications to discharge conditions and make amendments under s.96A of the Town and Country Planning Act are not impacted, unless the amendment would clearly increase likely water consumption. Such an amendment would be considered a material change.
Will the Council require demonstration of water neutrality where it can be shown that the application site abstracts its water from a different source to Hardham?
If development is not supplied by the abstractions in Sussex North Water Supply Zone, then there would be no need to demonstrate water neutrality. The applicant will however, need to evidence where the supply to their site comes from and obtain Southern Water’s agreement that the supply is sourced from outside the supply zone.
What is the process Horsham District Council needs to follow?
S.63 of the Conservation of Habitats and Species Regulations 2017 sets out the process the competent authority (in this case HDC) must follow. The Planning Practice Guidance sets out further detail in it’s dedicated Appropriate Assessment chapter.
For those applications that will create demand (regardless of any existing use of the site) for mains water from the Sussex North Supply Zone, the applicant must submit a Water Neutrality Statement setting out the existing and proposed water consumption figures and a scheme for how water neutrality will then be achieved. The requirement for a Water Neutrality Statement is now a local validation requirement.
The Council will first screen the proposals to assess whether a significant effect on the Arun Valley is likely either alone or in combination with other plans/projects. Mitigation cannot be taken into account at this stage. For instance, if your proposal seeks to reduce water consumption below 110 litres per person per day (the maximum volume required by our current development plan), and/or offset proposed water consumption on another site, then this forms mitigation that cannot be considered at screening stage.
Where proposals have been screened in (ie they are determined to have a likely significant effect), the Council is required to consider the proposed mitigation as part of an Appropriate Assessment. The Planning Practice Guidance states that ‘an appropriate assessment must contain complete, precise and definitive findings and conclusions to ensure that there is no reasonable scientific doubt as to the effects of the proposed plan or project’ (PPG para 003). The success of the Appropriate Assessment process is therefore highly reliant on the robustness of the evidence presented by applicants. Vague, incomplete or ambiguous data will not be sufficient to enable a proposal to successfully pass through Appropriate Assessment.
The Council will assess the water neutrality statement and strategy and if we consider it a sufficiently precise, credible and deliverable means of achieving water neutrality, we will pass the statement to our specialist ecology consultants to undertake the Appropriate Assessment required by s.63 of the Habitats Regulations. Our ecology consultants will be targeted to respond within 14 days.
In the event the strategy passes Appropriate Assessment, the Habitat Regulations require that it is then passed to the appropriate nature conservation body (in this case Natural England) to comment within a ‘reasonable time as the authority specifies’. We consider 21 days to be a reasonable time for a response, as per the standard consultation response times.
In the event Natural England do not object, we will be able to then grant planning permission in the event all other matters are acceptable.
As the HRA consultation process takes a number of weeks to complete (at least 5 weeks from the receipt of an acceptable water neutrality strategy), officers will look to agree suitable extensions of time with applicants as necessary and at the appropriate time.
Is development granted by the Town and Country Planning (General Permitted Development) Order impacted by water neutrality?
Development granted under the General Permitted Development Order (GPDO) must still demonstrate water neutrality. S.3 of the GPDO states that planning permission is granted by the GPDO only where the provisions of the Order and s.75-78 of the Habitat Regulations have been complied with. S.75-78 of the Habitats Regulations sets out a strict process to be followed for development otherwise granted by the GPDO where that development would result in an impact on a habitats site. If development granted by the GPDO will generate water consumption, it will not be lawful permitted development unless and until the process contained within s.75-78 of the Habitat Regulations has concluded no adverse impact on the Arun Valley sites will occur.
In these situations, our current approach is to grant applications for Prior Approval and Prior Notification as normal based on the relevant GPDO criteria, however our decision notices will refer to the need to separately comply with the Habitat Regulations in order to be lawful. Any such development will therefore not benefit from permitted development until an application to the Council under s.77 of the Habitats Regulations has been made and has been determined positively.
Please note that as set out above, development granted under Parts 1 and 2 of Schedule 2 of the GPDO have been screened out from having a significant effect and therefore from being required to demonstrate water neutrality. Therefore, any development granted under Parts 1 and 2 of Schedule 2 does not need to comply with s.75-78 of the Habitat Regulations.
How should Water Neutrality Statements be presented?
As a general guide, we would expect a Water Neutrality Statement to cover the following elements:
Explain the purpose of the statement and the reason for its submission.
Outline the background to the statement. This includes details of the site, including its existing or most recent use, any extant permissions, and details of the current proposal.
It is critical that the statement clearly establishes what the baseline water consumption rate is for the existing or most recent use. Where historic water bills for the site are not available, alternative data using the Building Regulations Part G or BREAM water calculators should be used, along with appropriate occupancy rates and consumption data for any industrial processes being undertake at the site. The data should be presented in litres per person per day. Further information is set out separately below. It is critical that existing baseline consumption is fully evidence to give certainty of the actual mains water being use at a site. Metered water bills are the best way to achieve this certainty.
This section will calculate what the water demands will be from the proposed development. The data should be presented in litres per person per day and reflect the average occupancy of the development. For business uses, the proposed consumption data must include consumption used for any proposed industrial processes
Water Reduction Measures
Where the proposed water consumption is higher than the baseline consumption, you must first consider reducing water consumption in the proposed development through installing more water efficient fixtures and appliances. Completion of the Part G or BREEAM water calculators will help demonstrate the savings to be made. Where highly efficient appliances are to be installed, details of an appliance that meets that high standard of water consumption should be submitted to demonstrate the efficiencies are achievable.
Once all efficiency opportunities have been exhausted, water re-use through rainwater harvesting and/or greywater/blackwater recycling should be then considered. Further details below.
The use of efficiencies and rain/grey water harvesting technologies alone will be unlikely to make some developments water neutral. In most such cases, such as new build on greenfield sites, offsetting measures to reduce water consumption on other land and property will be required in order to achieve water neutrality. Where offsetting on third party land, full details and evidence of the third party landowner’s existing water consumption must be submitted, along with the full details of the efficiencies to be implemented and how the efficiencies will be maintained in future (this could be through a maintenance contribution to the landowner for instance). This can include existing water bills and evidence of the efficiency of the existing fixtures and appliances. Where offsetting is to be carried out on third party land, that landowner will be required to enter into a legal agreement to install and retain the measures in perpetuity.
Offsetting cannot be carried out on third party land that does not take its water from the same North West Sussex Supply Zone.
It is important the conclusion summarises the water figures in a clear manner and sets out clearly the detail of any mitigation strategy necessary to achieve neutrality.
How to evidence baseline water consumption
For residential schemes, we will expect to see water consumption calculations for any existing use of the site, and the proposed use. These must be set out in litres per person per day (l/p/d). For residential uses, copies of recent metered water bills within the last three years is the best evidence of existing consumption. Our preferred alternative approach is for the calculations to reflect the average occupancy rate of a dwelling of that size. This creates a fair and consistent way to calculate water consumption for a dwelling. Based on extrapolated 2011 census data for Horsham District, average occupancy data is as follows:
- One-bedroom dwellings: 1.32 occupants
- Two-bedroom dwellings: 1.88 occupants
- Three-bedroom dwellings: 2.47 occupants
- Four-bedroom dwellings: 2.86 occupants
- Five-bedroom dwellings: 3.09 occupants
In terms of per person water consumption data, work carried out for our new Local Plan has used water company data to calculate that existing water consumption rates average at 135 l/p/d. These are the best figures to use as they are based on known data and enable a consistent approach to be made.
We are aware that the Southern Water website holds average consumption figures for household sizes, however to apply that data requires making assumptions about how many people occupy a dwelling. Our current opinion is that applying average occupancy and water consumption rates is the fairest and most robust method to take, and will help consistency of decision making.
In order to demonstrate future consumption rates, you are advised to complete a Building Regulations Part G calculator or equivalent. The data used should be realistic based on fixtures and fittings available on the market, and be reflective of the existing use and proposed use. It should be noted that achieving water reductions to under 85 l/p/d is understood to be very challenging unless rainwater harvesting and/or greywater recycling is included. Please be mindful of applying the standard 5lpd for external consumption if that dwelling does not have outside space. Where no washing machines are proposed in a dwelling, we would expect the standard washing machine consumption rates to be used in the Part G calculator as any occupant would still need to wash their clothes.
The proposal is to replace 4x2-bed flats with 1x 3-bed house and 3x4-bed houses.
Existing baseline consumption
2-bed flats have an average occupancy of 1.88 persons each, consuming on average 135 litres per person per day, so the existing water consumption would be 1.88 x 4 x 135 l/p/d = 1,015.2 litres per day in total
A 3-bed house has an average occupancy of 2.47, and a 4-bed house has an average occupancy of 2.86. Total proposed occupancy would therefore be 2.47 + (3 x 2.86) = 11.05 persons
To be water neutral, the 11.05 average occupants must not consume more than 1,015.2 litres per day in total. This works out at consumption of 91.87 l/p/d (1,015.2 / 11.05)
Mitigation through improved water efficient fixtures and appliances, and/or rainwater harvesting, would be required, to be evidenced through a Part G water calculator. This mitigation would require the Council to undertake an Appropriate Assessment to pass HRA.
The best way to evidence existing mains water consumption is via copies of metered water bills from within the last three years. The bills should cover the period before Covid as well as after as the lockdowns will have affected consumption at many sites. Unmetered water bills will not be accepted. Where there are other uses on a site, or the use is shared across multiple other buildings and land, it will be difficult to evidence with certainty the actual water use from a building unless separately metered. This is particularly the case for agricultural buildings. In such scenarios we will likely only be able to consider existing water consumption as nil. In cases where you are evidencing water consumption from agricultural uses, it will need to be clear that the water consumed is coming from the mains supply, and not watercourses or other rain collecting means.
When evidencing proposed consumption, we recommend you complete a BREEAM Wat 1 water calculator or an appropriate equivalent industry standard water calculator to estimate proposed employee water usage. Where necessary OffPAT employment density figures can be used to calculate average employee numbers a site and use could employ
Water consumption data for commercial uses must also include water consumed in any industrial or cooking process carried out on the site.
We will need to assess each case on its merits. We will also need to consider alternative permitted uses within Class E, or industrial occupiers under class B2, for instance, which could vary considerably in their water consumption, when assessing proposed consumption rates. Conditions may be applied to restrict alternative uses if there is concern they may breach the water neutrality strategy.
Please note this advice may evolve in future as we receive and examine more water neutrality strategies.
Can I use the fallback consumption of an existing unbuilt planning consent when calculating the existing baseline consumption rate?
The use of a fallback consent as part of the evidence base for the existing water consumption on a site is capable of being considered. However, as the test of certainty to meet the Habitat Regulations sets a very high bar, it is not sufficient to simply rely on the possibility that a fallback scheme may be implemented in the event permission is refused. Instead, we must consider whether the fallback scheme would be implemented in the event permission is refused. To help demonstrate this, we will require evidence that all relevant planning conditions on the fallback scheme have been discharged, and written evidence that the applicant intends to then build the fallback scheme if permission is not granted.
Can I use the capacity of an existing site when considering existing water consumption at a site, or must I use only the known water usage at the time of application?
We have encountered many scenarios where water neutrality statements are basing existing consumption rates on the theoretical capacity of a site, rather than its actual last known water consumption rate. An example would be using the estimated water consumption from the full occupation of 20 stables, even though only 3 are currently in use. Another example would be estimating water consumption from a café/restaurant use permitted by Class E when the building is currently in retail use, or the last known use was retail.
In such scenarios we can only consider the actual current water consumption at the site, unless there is clear evidence of a higher consumption rate at the site in the last three years, such as from water bills and occupancy information. This three year test is consistent with the Natural England FAQs where Natural England consider three years an appropriate timescale when considering water use from a building now demolished. We will not consider evidence of higher water consumption beyond this three year period.
Do I need to demonstrate water neutrality when making an application for a minor material amendment under S.73 of the Town and Country Planning Act?
An application made under s.73 of the Town and Country Planning Act creates a new planning permission on a site therefore we must consider water neutrality as a new material planning consideration.
Where you have an existing full planning permission that has been commenced, any application made under s.73 will not need to demonstrate water neutrality as the implementation of the existing full permission would constitute a fallback. That is unless the amendment would likely increase water consumption over and above the existing permission. Where a full planning permission has not been commenced, any application made under s.73 will need to consider water neutrality with the existing un-commenced planning permission forming a fallback scheme. Evidence that the existing planning permission would be implemented in the event the s.73 consent is not granted would need to be provided, as set out above. In cases where the amendment would increase the water consumption of the previously approved development, water neutrality will need to be demonstrated.
Where you are seeking to amend an existing outline planning permission granted prior to the Natural England Position Statement that has been commenced, we would normally seek to apply a condition to require that water neutrality be addressed prior to the grant of any subsequent reserved matters applications, unless water neutrality has otherwise already been addressed. This would be consistent with how water neutrality would be addressed if the original outline permission was pursued instead.
Where an outline planning permission has not been implemented, we will apply the same test as set out above for amending an unimplemented full planning permission.
What about Water Re-Use Technologies?
Water reuse technologies such as rainwater, grey water and blackwater harvesting have the potential to save significant amounts of water. For example, 24% of water in the home is used for flushing the toilet and 4% externally in the garden, meaning a water reuse system could save at least a quarter of demand if it was installed for these purposes. Such technologies are though unlikely to provide sufficient savings to reach water neutrality without further offsetting.
The following Waterwise link and accompanying downloadable PDF may be of assistance:
What evidence do you require where rainwater harvesting is being proposed?
We will require details of the rainwater harvesting including the quantum of water capable of being harvested from the site and the means and capacity for storage to cater for drought. Drought storage should provide for at least 35 days supply to provide robustness to address climate change, equivalent to the most recent drought periods experienced in the region. Part G of the Building Regulations provides a methodology for calculating the amount of rainwater that can be captured. If rainwater harvesting is to be used for drinking water, then we will need to see evidence prior to occupation that the water has been independently certified as suitable for consumption alongside a longer term monitoring and maintenance programme.
What evidence do you require where rainwater harvesting is being proposed?
We will require details of the rainwater harvesting including the quantum of water capable of being harvested from the site and the means and capacity for storage to cater for drought. Part G of the Building Regulations provides a methodology for calculating the amount of rainwater that can be captured. If rainwater harvesting is to be used for drinking water, then we will need to see evidence prior to occupation that the water has been independently certified as suitable for consumption alongside a longer term monitoring and maintenance programme.
Will Horsham District Council be using their own consultants to assess Water Neutrality Statements for you?
We will look to ask water consultants to provide us with comments on strategies on a case by case basis. Where we require independent assessment from a consultant, we will contact you in advance and request confirmation first that the applicant will be reimbursing us for that consultation.
How will Horsham District Council seek to secure water neutrality strategies in any planning permission?
To secure the water neutrality strategy, we will apply a condition requiring that development be carried out in accordance with the strategy, with evidence to be submitted to us for approval prior to first occupation or use confirming that the strategy has been implemented in full. Evidence to meet this condition would include photographs of the installed features, their specification, and the completion of the Part G ‘as built’ table or equivalent. In some cases, depending on the type of mitigation being proposed (such as rainwater harvesting schemes), we will need to understand the longer term monitoring and maintenance programme for the mitigation.
Where offsetting on third party land is required to achieve neutrality, we will require the third party landowner to enter into a legal agreement to ensure the offsetting measures are evidenced as having been installed prior to first occupation or use of the approved development and are retained in perpetuity thereafter.
When will Horsham District Council negotiate amendments to a submitted water neutrality strategy?
It is important that decisions are made in a timely manner where possible and for us to appropriately manage the volume of work in the department to avoid undue delays for our customers. These FAQs contain detailed information to assist in the preparation of water neutrality statements and help ensure decisions are made without significant delay.
With this being the case if a statement has significant shortfalls in its methodology and/or its calculations then we will proceed to determine the application without further negotiation. If however it is considered that minor changes may make an impact on our determination to enable the grant of permission then we will look to seek those amendments wherever possible before a decision is made.
Is it possible to provide a water neutrality strategy on a site that is not in Horsham District?
Provided the mitigation is provided within the Sussex North Water Supply Zone it may be possible to provide mitigation outside of Horsham District, but it can be complex to negotiate and secure. The local planning authority for the chosen mitigation site will need to agree to enter into a legal agreement with Horsham District Council and all other parties to secure the mitigation and monitoring in perpetuity.
Will Horsham District Council accept a condition requiring no development take place until a water neutrality strategy has been submitted and approved?
Several applicants have suggested that we should secure a water neutrality strategy by condition, rather than requiring a strategy be agreed prior to the grant of planning permission. This is not an acceptable approach, as it does not provide for the necessary certainty that the impacts of the development on the Arun Valley sites can and will be mitigated to pass Appropriate Assessment. Any grant of planning permission absent of the up-front certainty that the impact on the Arun Valley can be mitigated would therefore be contrary to the Habitat Regulations.
Furthermore, it is established practice that ‘Grampian’ conditions should only be used where there is a reasonable certainty that the condition can be discharged within the lifetime of the permission. Given that some schemes will likely require offsetting on third party land to be considered water neutral, the absence of a known third party willing to undertake the necessary works means that there is no certainty that an appropriate strategy will be found within the lifetime of any permission.
Will Horsham District Council accept offsetting on its own property?
The Council is undertaking an assessment of its property holdings to ascertain how much offsetting it is capable of providing. This will take several months and at this stage any offsetting potential would likely be directed first at enabling Horsham District Homes affordable housing schemes to come forward. Given the likely ratio is in the region of 7:1 for the number of existing homes required to offset one new home, it is unlikely that there will be any spare capacity on Council owned property to offset private development.
West Sussex County Council have advised that they are also undertaking an assessment of their property holdings to ascertain how much offsetting they are capable of providing. This will also take several months and at this stage any offsetting potential would again be likely be directed first to deliver County Council projects such as expansions of schools. It is unlikely that there will be any spare capacity on Council owned property to offset private development but this will not be known until the assessment work is complete.
Can I just pay an offsetting charge instead?
Until the strategic solution has been identified and costed, it is unclear whether an offsetting charge will be necessary, when it will come into effect, and how much it would require applicants to pay to proportionately offset their development. At this stage there is no ability therefore to pay an offsetting charge.
Can I simply commit to meeting my water supply needs by importing water to my site by tanker from outside the supply zone?
In order to meet the test of certainty that no adverse impact will take place, we must be able to enforce any approved water neutrality strategy. A strategy such as importing all daily water needs will not be enforceable and is therefore not a strategy we will be able to support. Further advice is though being sought from Natural England and this question may be updated.
What about water consumed during the construction process for my development, will this need to demonstrate water neutrality throughout?
At this stage we consider that most construction timeframes are relatively short therefore we will not be actively seeking water neutrality for the construction phase. We will though include a requirement for Construction Environment Management Plans to include meaningful measures to reduce water consumption, which could include rainwater harvesting for wheel washing or wc use.
Will Horsham District Council grant planning permission for development that is not water neutral, but instead shows significant reductions in water consumption?
No, as such development would not be water neutral and therefore would have an adverse impact on the Arun Valley sites contrary to the legal requirements of the Habitat Regulations.
The Natural England Position Statement is a material consideration, and therefore capable of being outweighed by other matters. In light of the Council’s lack of five year housing supply, should you not be granting housing development even if it is not fully water neutral?
The Position Statement is a material planning consideration, however any impact on a habitats site contrary to the Habitat Regulations must necessarily carry great weight in decision making. Paragraph 180 of the NPPF is clear that planning permission should be refused for development that would result in significant harm to biodiversity and/or result in the loss or deterioration of irreplaceable habitats.
Furthermore, where an adverse impact on a habitats site is identified and constitutes a clear reason to refuse permission, the ‘tilted’ balance of NPPF 11d is not engaged (see footnote 7 to NPPF 11d, and NPPF 182). The absence of a five year housing land supply is not therefore reason to grant planning permission where water neutrality has not been demonstrated.
Has water neutrality been addressed in any appeal decision?
At this stage we are aware of two linked appeal decisions (ref: 3277840 and 3274485) in the South Downs National Park where an inspector refused two schemes on the same site, one for a single dwelling and an alternative scheme for two dwellings. Both appeals were dismissed owing to water neutrality having not been demonstrated, with this reasoning forming the only reason the appeal for the single dwelling was dismissed.