England and Wales High Court (Administrative Court) Decisions

IN THE HIGH COURT OF JUSTICE
QUEEN'S BENCH DIVISION
ADMINISTRATIVE COURT LEEDS

		Royal Courts of Justice Strand, London, WC2A 2LL
		30/07/2015

Mrs Justice Patterson:

Introduction

1. This is a challenge by Menston Action Group, a local action group, to the approval by Bradford Metropolitan District Council, the defendant, on 15 August 2014 of a drainage scheme submitted under condition 15 of planning permission 10/04551/MAF.
2. There are two grounds of challenge. They are:

i) Whether the defendant misdirected itself as to the meaning of condition 15 and thereby erroneously approved the submitted scheme; and

ii) Whether in making its decision on 15 August 2014 the defendant acted under a factual error.

3. The claimant is a group of local residents who live in the vicinity of the site with the benefit of planning permission 10/04551/MAF in Menston, Yorkshire. Professor Rhodes who has filed witness statements in the action has acted as a spokesperson for the action group.
4. The defendant is the local planning authority.
5. The interested party is the developer who submitted a planning application to develop up to 173 houses on a greenfield site of 5.43 hectares (the site) on the edge of the settlement of Menston.
6. The site had formerly been allocated as a phase 2 housing site in the replacement Bradford UDP. For reasons not relevant to the present case that allocation has not been carried forward but the defendant agreed to treat the prior allocation as a material consideration.
7. On 24 October 2013 the defendant granted planning permission to the interested party for residential development of 173 dwellings on land north-east of 2 The Coach House, Derry Hill, Menston, West Yorkshire. It was a conditional planning permission. Condition 15 is at the centre of the current proceedings. It reads:

"15. Development shall not begin until a surface water drainage scheme for water passing through the site, based on sustainable drainage principles has been submitted to and approved in writing by the local planning authority. This must include details of how the surface water runoff rate of 8.2 litres/second/ha will be maintained for up to and including the 1 in 100 year (plus climate change) rainfall event.

Reason: To prevent flooding by ensuring the satisfactory storage/disposal of surface water from the site."

8. The claimant had been concerned about the grant of permission on the site and had objected to the principle of the development on a variety of grounds one of which was drainage. That was a concern because of flooding which members of the group experienced in their gardens and which occurred in the general locality as photographs in the court bundle testify.
9. The claimant's concern was, and remains, that the drainage system submitted and approved under condition 15 does not comply with sustainable drainage principles.
10. Judicial review proceedings were commenced on 25 September 2014. At a subsequent oral hearing permission was granted by Stewart J for the case to proceed on ground 2 only. The claimant appealed his decision on ground 1. Sullivan LJ granted permission to proceed on ground 1 on the papers. The application has thus proceeded on both grounds.

Background

11. Because of the nature of the dispute between the parties it is necessary to set this section out in more detail than would ordinarily be necessary.
12. The site is currently an open field through which runs a watercourse. The watercourse is prone to flooding. There are significantly raised water levels at times of heavy downpour both in the field, in the adjacent gardens, around the nearby electricity substation and the road, Dicks Garth Road, beyond.
13. A flood risk assessment (FRA) was submitted by Eastwood & Partners as part of the planning application documents on 23 August 2010. That noted that the site was zone 1 on the Environment Agency's (EA) flood map. That meant that the site was categorised as "low risk" and was, therefore, appropriate for development. The assessment noted that there was an unnamed watercourse which ran through the site (south to north) from a catchment comprising steeply sloping rural landscape. The watercourse ran in open channel before discharging to a culverted system in the existing housing area bordering the site to the north (Menston Village). The system ran through the residential gardens before emerging in culvert in the public highway, Dicks Garth Road.
14. The assessment continued:

"We are not aware of any recorded flooding incidents on the site, other than water reportedly 'sheeting' down the slope during extreme storm events. This situation will be substantially improved as a result of the proposed development due to the interception of existing overland flows and positive drainage of the site."

15. The principal sources of potential flooding were noted to be:

Overtopping of the watercourse running through the site.

General run off from the steeply sloping land to the south.

Surcharging of proposed drainage and storm water storage systems.

16. The appropriate standard of protection was noted as 100 years plus climate change.
17. The FRA recommended that surface water was to be drained to the culverted watercourse downstream of the site. A restricted discharge was appropriate based on greenfield runoff. The calculated figure was 8.2 litres per second per hectare. Storage was proposed in a combination of below ground tanks and a detention basin designed in accordance with principles set out in the sustainable drainage SUDS manual. Land drainage was to be provided in the form of swales, ditches and/or filter drains at the top and bottom of the site connected to the watercourse running through the site. With the implementation of the recommended measures Eastwood & Partners did not consider that there would be any increased risk of flooding to other residential properties as a consequence of the development.
18. The EA were consulted and the surface water strategy to connect to the existing culverted watercourse in Dicks Garth Road had been discussed and agreed in principle with them.
19. Calculations for the capacity of the culvert were appended to the FRA. They showed that:

"The capacity of the open watercourse through the site exceeds the capacity of the culverted section downstream and is capable of delivering the existing natural run-off from the steeply sloping rural catchment upstream without restriction.

The section through the gardens has a capacity in the range 200-300 l/sec, approximately 15% of the natural 100 year natural flow from the catchment.

The system in the road has a capacity in the range 400 l/sec, upstream where the culvert first enters the road, to 1,000 l/sec at the downstream end of the surveyed section.

In comparison with the existing theoretical run-off from the catchment upstream as a whole, including the proposed development site, the system has capacity for a 1 in 1 year event or less. However, the section of culvert in the main road, towards the downstream end of the survey has capacity equivalent to a 1 in 10 year event.

By limiting the peak flow from the site to the natural 1 in 1 year rate, or less, this represents a reduction at 1 in 100 years of about 20% measured in terms of the average capacity of the culvert.

By connecting the site drainage to the watercourse downstream of the first section, the flood risk in the gardens bordering the site should be reduced. However, in view of the existing restrictions on capacity in this area, it is anticipated that the gardens will remain at risk of flooding relatively frequently, as at present."

20. The claimant was concerned that with up to 1,400 litres per second per hectare coming down the existing watercourse there would be the imposition of an additional load into an already overloaded system.
21. In January 2014 Mr Baines, Director with Eastwood & Partners, submitted an addendum to the FRA which sought to secure the discharge of planning condition 15. The basis of his approach was set out as follows:

"Firstly, it is to be noted that it is not the responsibility of the developer to resolve any existing flooding issues, but it is required that the situation is made no worse as a consequence of the scheme, and the approved Flood Risk Assessment (FRA) prepared in connection with the proposed development is based on this premise."

22. Various plans and calculations were appended to the addendum including plan 30864/066E of the highway retaining wall showing the culvert inlet. The addendum concluded:

"1. Flows generated on the site as a consequence of the new development will be managed within the adoptable drainage system. The discharge rate will be limited to a maximum 8.2 l/sec per hectare as required by the Condition 15, with below ground storage sufficient for a 1 in 100 year storm event plus allowance for climate change.

2. Overland flows from the wider catchment to the south of the site are unaffected by the development, but the addition of swales along the site boundary will assist with attenuation without increasing flood risk.

3. Excess storm water over spilling the eastern bank of the watercourse will be channelled to the open area to the north of the road where the ground will be shaped to ensure provision of a 'field' storage volume greater than existing, mimicking the existing situation as far as possible."

23. On 1 August 2014 the claimant's solicitor emailed officers at the defendant asking that no decision be taken on the discharge of condition 15 until further consultation was carried out with his client. A week later the claimant's solicitor wrote again setting out the claimant's concerns and seeking a discussion of the drainage proposals which were said to be entirely inadequate and misconceived. The letter of 7 August 2015 summarised the claimant's understanding of the proposed submitted scheme as follows:

"Barratt Homes' current drainage scheme proposes three key steps to comply with the drainage pre-condition:-

That swales be constructed at the top of the site 'to assist in the maintenance of surface water flows across the site';

That the existing watercourse at the site be excavated to increase water flow down the site; and

That a culvert be placed near to the exit of the site (and near to the bottom of the excavated watercourse) which is capable of carrying 1400 l/s of water away from the site."

The letter continued that the onsite culvert would merely act as a continuation of the existing watercourse and water would then reach the further culvert where the capacity was restricted to 400 litres per second. The consequence was that, in times of rainfall and where the full capacity of the proposed 1,400 litres per second culvert was required, there would be 1,000 litres per second of water that was not able to go through the second culvert. As there was nowhere for the additional water capacity to go that would inevitably result in considerable additional flooding at Moorfield Avenue and the surrounding area. As a result the drainage proposals were unsatisfactory and did not comply with sustainable drainage principles.

24. The letter referred to the defendant's responsibility as a lead local flood authority under the Flood and Water Management Act 2010.
25. A series of emails and letters then took place between the claimant's solicitors and the defendant. The claimant's solicitors threatened judicial review proceedings in a letter dated 21 August 2014.
26. The defendant responded in a letter of 28 August 2014. In that the defendant made it clear that:

i) it had never given any assurance that there would be further consultation with the claimant on the "volume of water at Derry Hill and potential flood risks"; and

ii) the drainage officers were satisfied, having seen the drainage details, that although there would be a new 12 metre length of culvert within the site there would be no change to the quantity of flow or the discharge point.

The letter continued:

"For this reason, and having regard to the underlying basis that the purpose of the drainage proposals for this and any other site must be not to create new flooding risks or to worsen any existing flood risk, not to put in place a scheme with the purpose of alleviating any existing flood risk as the latter would involve looking at a wider set of parameters which are outside the responsibility of developers, the Drainage officer's advice was that your client's concerns were not such that any decision on the submitted drainage details should be delayed, let alone that those details should be rejected.

…

The council does not consider that its decision to issue the detailed consent is either irrational or unlawful. For the reasons outlined above it considers that the applicants' proposals do satisfy the test which applies here in contrast to that which would apply if a flood alleviation scheme was being proposed. For the same reasons the Council considers that it has complied with the relevant parts of the 2010 Act. The Council will deal with any application for consent under the 1991 Act as amended as and when this becomes necessary and/or an application is made."

27. The claimant's solicitors then sought the documents relied upon by the defendant's drainage officers in reaching their conclusions. In an email dated 3 September 2014 the defendant identified drawing 30864/026C which was on the planning portal and showed a new culvert of about 12 metres in length within the site and on the line of the existing watercourse to enable the construction of the estate road above it. The defendant said that the installation of the culvert would not alter the flow catchment of the watercourse and, therefore, flows through it would not be increased compared to the existing situation.
28. On the 15 September 2014 the claimant's solicitors wrote asserting that condition 15 had been interpreted without reference to sustainable drainage principles which were set out in the National Standards for Sustainable Drainage Systems Consultation Paper of December 2011. Further "the assertion in the 2014 report, as above, that the only requirement is to make the situation 'no worse' is incorrect." Accordingly the defendant's approval of details was unlawful.
29. The defendant replied on 18 September 2014. That letter where relevant says:

"1. The concept of sustainable drainage is that such systems should be used where ever possible and viable in preference to the traditional approach of the use of the public sewage and drainage system. The underlying aim is to slow the rate of surface water runoff and improve filtration, so mimicking natural drainage in both rural and urban areas. The Council seeks to ensure such systems are used and this is reflected in the approach of its drainage officers to all development proposals.

2. The principles and practical implementation of sustainable drainage are evolving. The national standards of sustainable drainage consultation paper in December 2011 is part of that process leading to the current latest draft of the national standards and specify criteria for sustainable drainage published in June 2014. …As a developing concept the principles have not yet been adopted as final policy but are accepted but are accepted by local authorities and developers. They are invariably enshrined in the requirements of planning conditions such as condition 15.

3. In so far as they can do so as an evolving concept the Council's drainage officers apply the principles of sustainable drainage when considering all drainage schemes whether or not there is any reference to those principles in the submitted schemes. In zone 1 areas, as in this case, the officers also apply the policy aims of looking to reduce the overall level of flood risk in the area and beyond through the layout and form of the development, and the appropriate application of sustainable drainage systems, and of ensuring that the proposed development will not make any existing flood risk worse.

4. In this case the drainage officers were, and are, satisfied that the drainage scheme described in the 2014 report and other submitted documents shows that the development will not make the existing flood risk situation any worse and that elements of the scheme could result in a reduction of the overall flood risk in the area…"

30. On 22 September 2014 the claimant's solicitors wrote to the defendant expressing their understanding, based on drawing 30864/26 revision C, that the existing watercourse was to be excavated up to the point of a new culvert under the new estate road. The effect of that was to funnel all of the water that would previously have left the watercourse over the length of the site would escape over a much smaller boundary. That would increase flooding in the areas of the electricity substation and the surrounding properties. The consequence was that what was proposed made flooding worse and could not comply with the defendant's own interpretation of sustainable drainage principles.
31. On 23 September 2014 the defendant's drainage officers, Mr Norfolk and Mr Poole, met with the defendant's solicitor, Mr Driver, to discuss the defendant's reply to the claimant's letter of the previous day. Mr Driver had a suggested draft response to which the engineers proposed amendments. The relevant parts are set out below:

"1. The various documents referred to in my letter of 18^th September are the suite of documents to which drainage engineers, including those of the Council and no doubt your client's consultant engineers, refer to to one extent or another in considering all drainage proposals. They are so much part of the information that professional drainage engineers take into account in that way in preparing and considering drainage proposals that my Drainage colleagues did not consider it necessary to refer to them separately until your letter of 15^th September.

…

2. The 2011 consultation paper was also one of those documents. As that was a consultation document, and it has since been revised it was not considered necessary to specifically refer to it. However, my letter of 18^th September set out in detail the way in which the Council's Drainage engineers applied the standards set out in the 2011 consultant paper when considering the current proposal.

…

5. Turning to the seventh to tenth, also fifth, paragraphs of your letter, the approved proposal does not involve the excavation of the existing watercourse up to the point of the new 1200 mm diameter culvert you refer to. That part of the watercourse, and the rest of the watercourse within the site beyond that culvert will not be altered at all, the only change in that length being the new culvert under the estate road.

…

6. The other main change to be made in accordance with the approved scheme is the introduction of a new water storage 'basin' within the lowest part of the site closest to the [northern] site boundary. This basin area – which will remain as open space – will have a capacity of 68 cubic metres which is significantly above the capacity of 36 cubic metres which has been calculated by the developers' drainage engineers and accepted by the Council's Drainage section as being the amount of water which currently can accumulate based on the JBA modelling. The Council considers that the addition of this water storage basin with a significantly larger capacity than the existing area will be an improvement on the current situation and is therefore likely to lead to a reduction, rather than increased, flood risk."

32. On 24 September 2014 Mr Driver emailed the agreed response to the claimant's solicitors.
33. On 25 September 2014 the judicial review claim was issued. The statement of facts and grounds continued (at paragraph 32) to claim that the existing watercourse was to be excavated up to the point of the new 12 metre culvert. Professor Rhodes in his witness statement of 24 September 2014 made the claimants' position clear when he said:

"8. The members of the Menston Action Group are residents of the Menston area and are very concerned about flooding in Menston, a problem that will be exacerbated if the development at Derry Hill is allowed to proceed on the terms approved by the Defendant. We are concerned that the Defendant has not properly considered these issues in deciding to approve the current scheme and that, as a result, significant damage to property will take place and there will be a risk to public health and safety."

34. The statement of facts and grounds was amended on 2 October 2014 to include an allegation that the approved proposal did involve additional work to the watercourse other than the mere insertion of the culvert. Further, the defendant's decision, based as it was, on there being no excavation up to the point of insertion of the new culvert was based on a mistake of fact.
35. Against that somewhat lengthy background I turn to deal with the grounds.

Ground 1: Did the Defendant Misdirect Itself as to the Meaning of Condition 15 and Thereby Erroneously Approve the Submitted Scheme?

36. The claimant submits that for the defendant to approach the condition on the basis of not making matters worse was flawed. There should have been, but there was not, consideration of the potential to alleviate existing flooding.
37. The claimant relies upon Telford & Wrekin Council v Secretary of State for Communities and Local Government [2013] EWHC 79. In particular reliance is placed on paragraph 33 of Beatson LJ's judgment where he says:

"Although the submissions focussed on the Sevenoaks and Hulme cases, a number of other authorities were put before me, including some that were not considered in Hulme's case, and which Mr Lockhart-Mummery said he had been informed by counsel in that case had not been cited to the court. I first summarise my understanding of the effect of the authorities put before me on the construction of a planning permission (and of the conditions in it):-

(1) As a general rule a planning permission is to be construed within the four corners of the consent itself, i.e. including the conditions in it and the express reasons for those conditions unless another document is incorporated by reference or it is necessary to resolve an ambiguity in the permission or condition: R v Ashford DC, ex p Shepway DC [1998] PLCR 12 at 19 (Keene J); Carter Commercial Developments v Secretary of State [2002] EWCA Civ 1994 at [13] and [27] (Buxton and Arden LJJ); Sevenoaks DC v First Secretary of State [2004] EWHC 771 (Admin) at [24] and [38] (Sullivan J); R (Bleaklow Industries) v. Secretary of State for Communities and Local Government [2009] EWCA Civ 206 at [27] (Keene LJ); R (Midcounties Co-operative Limited) v. Wyre Forest DC [2010] EWCA Civ 841 at [10] (Laws LJ).

(2) The reason for the strict approach to the use of extrinsic material is that a planning permission is a public document which runs with the land. Save where it is clear on its face that it does not purport to be complete and self-contained, it should be capable of being relied on by later landowners and members of the public reading it who may not have access to extrinsic material: Slough Estates v Slough Borough Council [1971] AC 958 at 962 (Lord Reid); Carter Commercial Developments v Secretary of State at [28] (Arden LJ); R (Bleaklow Industries) v. Secretary of State for Communities and Local Government [2009] EWCA Civ 206 at [27]) (Keene LJ); Barnett v Secretary of State [2009] EWCA Civ 476 at [16] – [21] (Keene LJ, approving Sullivan J at first instance); R (Midcounties Co-operative Limited) v. Wyre Forest DC [2010] EWCA Civ 841 at [10] (Laws LJ).

(3) It follows from (2) that in construing a planning permission:-

a. the question is not what the parties intended but what a reasonable reader would understand was permitted by the local planning authority, and

b. Conditions must be clearly and expressly imposed, so that they are plain for all to read.

As well as the cases cited at (2), see Sevenoaks DC v First Secretary of State [2004] EWHC 771 (Admin) at [38] and [45] (Sullivan J).

(4) Conditions should be interpreted benevolently and not narrowly or strictly (see Carter Commercial Development Ltd v Secretary of State for the Environment [2002] EWHC 1200 (Admin) at [49], per Sullivan J) and given a common-sense meaning: see Northampton BC v First Secretary of State [2005] EWHC 168 (Admin) at [22] (Sullivan J).

(5) A condition will be void for uncertainty only 'if it can be given no meaning or no sensible or ascertainable meaning, and not merely because it is ambiguous or leads to absurd results': Fawcett Properties v Buckingham County Council [1961] AC 636, 678 per Lord Denning. In Hulme's case Elias LJ stated this was an application of the benevolent construction principle.

(6) If there is ambiguity in a condition it has to be resolved in a common sense way, having regard to the underlying planning purpose for it as evidenced by the reasons given for its imposition: Sevenoaks DC v First Secretary of State [2004] EWHC 771 (Admin) per Sullivan J at [38] accepting the submission at [34].

(7) There is no room for an implied condition in a planning permission. This principle was enunciated in Trustees of Walton on Thames Charities v Walton and Weighbridge District Council (1970) 21 P & C R 411 at 497 (Widgery LJ), in the following terms:

'I have never heard of an implied condition in a planning permission and I believe no such creature exists. Planning permission enures for the benefit of the land. It is not simply a matter of contract between the parties. There is no place, in my judgment, within the law relating to planning permission for an implied condition. Conditions should be express, they should be clear, they should be in the document containing the permission.'

This principle also precludes implying an obligation by way of an addition to an existing condition: Sevenoaks DC v First Secretary of State [2004] EWHC 771 (Admin) at [45] (Sullivan J)

(8) Where planning permission containing conditions has been granted in a decision by an Inspector allowing an appeal, and a condition is ambiguous, it is possible to construe it in the context of the decision letter as a whole: Hulme's case at [13(a)]. Doing this does not involve impermissible 'implication' from an extrinsic source, but is best described as a question of 'construction': Hulme's case at [37]. In Hulme's case, Elias LJ stated (at [37]) that even 'if it can be described as an implied condition it is very different in nature from that envisaged in the Trustees of Walton case.'"

38. Condition 15 required the submission and approval of a scheme for water passing through the appeal site. There is no problem with the wording of the condition; the issue is how it should be interpreted. The reason for the condition makes it clear that it was intended to relate to matters offsite.
39. Sustainable drainage principles are not defined in the permission or in any incorporated documents. To understand what is meant by the phrase the decision maker should have regard to the Flood and Water Management Act 2010. It is accepted that schedule 3 of the Act is not in force but the Act is the only statutory source for the meaning of sustainable drainage principles. Paragraph 2 of schedule 3 reads:

"2. 'Sustainable drainage' means managing rainwater (including snow and other precipitation) with the aim of—

(a) reducing damage from flooding,

(b) improving water quality,

(c) protecting and improving the environment,

(d) protecting health and safety, and

(e) ensuring the stability and durability of drainage systems."

40. That illustrates that sustainable drainage principles include making things better. The approach of the defendant was that a submitted scheme had to make matters no worse is inconsistent with sustainable drainage principles.
41. The National Standards for Sustainable Drainage Systems published for consultation in December 2011 illustrate that the policy direction is to reduce the risk of flooding. Paragraph 0.2 in the executive summary of the document reads:

"SuDS are an approach to managing rainwater falling on roofs and other surfaces through a sequence of actions. The key objectives are to manage the flow rate and volume of surface runoff to reduce the risk of flooding and water pollution. SuDS also reduce pressure on the sewerage network and can improve biodiversity and local amenity."

Paragraph D5 of the document informs the understanding of what sustainable drainage systems means. It reads:

"Drainage systems must be designed so that, unless an area is designated for flood management in the Local Flood Risk Management Strategy, flooding from the drainage system does not occur;

a) On any part of the site for a 1 in 30 year rainfall event; and

b) During a 1 in 100 year rainfall event in any part of:

•    a building (including a basement); or

•    utility plant susceptible to water (e.g. pumping station or electricity sub-station; or

c) On neighbouring sites during a 1 in 100 year rainfall event."

42. Conditions have to be construed by their meaning at the time of their imposition. In this case that is October 2013.
43. The National Planning Policy Guidance (NPPG) deals with flood risk at paragraph 7-050-20140306 which says:

"Local authorities and developers should seek opportunities to reduce the overall level of flood risk in the area and beyond. This can be achieved, for instance, through the layout and form of development, including green infrastructure and the appropriate application of sustainable drainage systems (further information here and here), through safeguarding land for flood risk management, or where appropriate, through designing off-site works required to protect and support development in ways that benefit the are more generally."

44. In addressing the question 'why should priority be given to the use of sustainable drainage systems?' paragraph 7-051-20150323 says:

"Sustainable drainage systems are designed to control surface water run off close to where it falls and mimic natural drainage as closely as possible. They provide opportunities to:

reduce the causes and impacts of flooding;

remove pollutants from urban run-off at source;

combine water management with green space with benefits for amenity, recreation and wildlife."

All of the policy guidance is of a piece with including improvement to the existing situation. That is why in granting permission to apply for judicial review on ground 1 Sullivan LJ had said that:

"Ground 1 passes the arguability threshold for the reasons set out in the claimant's skeleton argument. Whether a condition which does more than merely ensure that a development does not make existing flooding worse is necessarily unlawful is a question of wider public importance."

45. That brings the well known case of Newbury District Council v Secretary of State for the Environment [1981] AC 578 into play. It is not for the court to carry out its own judgment but to consider whether no reasonable local planning authority could interpret condition 15 as the defendant had done.
46. Delta Design & Engineering Limited v Secretary of State for the Environment, Transport and the Regions & Another [2000] 80 P&CR 76 held that it was not open to a judge to decide an issue of lawfulness of a planning condition himself in circumstances where an inspector had jurisdiction to determine that issue.
47. Carter Commercial Developments Limited v Secretary of State for Transport, Local Government and Regions [2002] EWCA Civ 1994 is not limited to a situation where the responsibility of a developer is simply not to make a pre-existing situation worse.
48. The defendant by restricting the scheme approved to the on site position imposed a limit which was not within the condition given that the wording of the condition itself envisaged improvement.
49. The defendant submits that once it is accepted that condition 15 can be satisfied by a scheme that provides no betterment of the existing situation the defendant cannot be criticised for accepting a scheme such as that submitted. It is up to a developer what he submits. What is submitted is what the defendant has to determine.
50. For the claimant to establish its case sustainable drainage principles have to include betterment.
51. The aim to achieve greenfield runoff rates is important. That will bring some improvement. That is entirely consistent with guidance on sustainable drainage in the NPPG.
52. In force at the relevant time was the National Planning Policy Framework (NPPF), Planning Policy Statement (PPS) 25 Practice Guide and Circular 11/95. All are material considerations for the decision maker.
53. The relevant paragraphs in PPS25 Practice Guide are 5.3, 5.6, 5.9, 5.11 and 5.13:

"5.3. Sustainable drainage systems, or SUDS, can better manage the risk of surface water flooding, as well as improving water quality by reducing the amount and rate of water flow by infiltration, storage, attenuation and slow conveyance.

…

5.6. Conventional surface water drainage uses underground piped systems designed to remove surface water from a site as quickly as possible. This may result in flooding problems downstream and reduce the recharging of groundwater. Conventional drainage can also create a direct pathway for pollutants from urban areas to pass into watercourses and groundwater.

…

5.9. For new developments, the best way of reducing flood risk within the development is to:

• control the water at source through sustainable drainage systems (SUDS).

• consider exceedance i.e. what flow paths will be taken by excess surface water ('the major drainage system') when the capacity of the drainage system is exceeded.

…

5.11. SUDS mimic natural drainage and reduce the amount and rate of water flow by

• infiltration into the ground,

• holding water in storage areas, and

• slowing the flow of water.

…

5.13. SUDS achieve multiple objectives; they remove pollutants from urban run-off at source, control surface water run-off from developments, ensure that new developments do not increase flood risk downstream, and combine water management with green space which can increase amenity, recreation and biodiversity value."

54. What was proposed was entirely consistent with sustainable drainage principles in the use of swales and the detention basin.
55. The witness statement of Mr Baines, the Director of Eastwood & Partners with responsibility for the FRA and drainage proposals for the interested party, reviewed policy documents in play at the time of submission. They include the SUDS manual printed in 2011, the Environment Agency Flood Risk Assessment Guidance Note 1, the Pitt review as well as the NPPF and NPPG. None of them suggest that there was a requirement for a drainage scheme to address offsite flooding not created or made worse by the development proposed. The claimant's submission is that although the condition does not require betterment it is to be interpreted with that meaning.
56. Where planning permission is granted in an area of flood risk it is right to impose an obligation on a developer to resolve problems caused by his development and not to worsen the situation elsewhere. There are good public policy reasons for so doing.
57. The test is what a reasonable reader would understand by the condition interpreted in context.
58. In Newbury (supra) the test was whether the condition imposed was necessary, related to planning and was fairly and reasonably related to the development proposed. There was no requirement to solve pre-existing problems. The absence of a power to impose a condition which was not fairly and reasonably related to the development which was to be permitted was restated in Elmbridge Borough Council v Secretary of State for the Environment [1989] JPL 277.
59. In Delta Design (supra) it was held that it was not open to a judge to decide an issue of lawfulness of a planning condition himself in circumstances where an inspector had jurisdiction to determine that issue.
60. In Carter Commercial the Court of Appeal considered whether a somewhat ambiguously worded condition could refer to a pre-existing problem offsite or whether it related to problems onsite. Arden LJ, Buxton LJ and Ward LJ all determined that the condition related to matters created by the development on site.
61. With that background and the established principles of interpretation of conditions, which the claimant agreed the development had to be interpreted to conform with, the test of whether the condition was fairly and reasonably related to the development applied. It is quite clear that pre-existing offsite flooding was not made worse by the development. Therefore, any scheme which improved that was not necessary nor fairly or reasonably related to the development.
62. On betterment the owner of land with planning permission has no responsibility elsewhere to improve the situation for others.
63. The Flood and Water Management Act 2010 was dealing with a separate regime with different approving bodies. Drainage systems were defined in Schedule 3 in paragraph 1(b) which may be applicable to the swales and detention basin but has nothing to do with the interpretation of condition 15. Schedule 3 paragraph 2 upon which the claimant places reliance can equally mean onsite as well as offsite measures.
64. The 2011 consultation document has now been superseded by Draft National Standards and Specified Criteria for Sustainable Drainage published in June 2014. No weight can therefore attach to the 2011 version.

Discussion and Conclusions

65. The issue is whether the meaning given to condition 15 by the defendant is one which no reasonable local planning authority could have given to and/or is as a result of misdirection on the defendant's part.
66. Condition 15 and the reason for its imposition are set out above. It occurs within a suite of planning conditions dealing with drainage, namely, conditions 14 to 18. Its focus is upon surface water disposal.
67. The claimant submits that conditions 14, 17 and 18 clearly relate to the site. Condition 16 is dealing with the construction phase of development and so relates to different circumstances. Condition 15 by reason of its reference to water passing through the site and the reason for its imposition expressed as to prevent flooding by ensuring satisfactory storage/disposal of surface water from the site shows that the condition has a wider reach than simply the application site.
68. As a matter of the ordinary and natural meaning of the words used within the condition I reject the claimant's submission. The words used in the condition can apply equally only to the appeal site. Condition 15 is a Grampian condition seeking to secure a surface water drainage scheme within certain parameters, such as surface water runoff at 8.2 litres per second per hectare. The level of runoff was fixed to mimic the greenfield runoff rate. The words "water passing through the site" in their ordinary and natural meaning do not carry any broader meaning than dealing with surface water within the application site itself. Likewise the words within the reason, "to prevent flooding…from the site" are, in my judgment, to secure an onsite scheme without deleterious effect offsite. As a matter of simple construction and subject to the meaning of "sustainable drainage systems" the defendant came to a conclusion that it was perfectly entitled to and one which was well within the scope of reasonable decisions that any local planning authority could reach.
69. In considering conditions I regard it as relevant to first consider the legal position and then the policy position. Each will be relevant at the time of imposition of the condition and at the time of its discharge, if required and if different. To hold, as the claimant submits, that the position is, in effect, frozen at the time of the grant of planning permission is unrealistic. There may be different policy advice between the grant of consent and the discharge of a condition which is highly relevant as to how the condition should be discharged. For a decision maker to ignore that would be both a very blinkered approach and would be to disregard a material consideration in the discharge of the condition.
70. The claimant poses the question as to whether a decision maker who reached a conclusion, as the claimant submits should be the case, namely, that there should be positive improvement of the drainage position or, alternatively, that the decision should at least consider whether there can be positive improvement on a proper interpretation of condition 15, would necessarily reach a perverse conclusion. In my judgment, that is putting the question the wrong way round. The question here is whether the decision which has been reached on the part of the defendant, on its interpretation of condition 15, is necessarily perverse. That would appear to be the reason why Sullivan LJ, when granting permission to bring the application on ground 1, phrased his grant of permission in the way that he did.
71. The case of Newbury establishes that for a condition to be valid it has to be fairly and reasonably related to the proposed development and be imposed for planning purposes. In this case the issue is simply whether the condition is fairly and reasonably related to the proposed development. In Newbury a condition requiring the removal of two pre-existing aircraft hangers after their use for storage purposes was held not to fairly and reasonably relate to the development permitted and was void. Viscount Dilhorne described the exercise this way:

"This appears to me in substance to be a repetition in different language of the inspector's conclusion. The Secretary of State agreed with him as to the object the local planning authority had sought to achieve. They both emphasised the substantial nature of the existing buildings. The contention that the Secretary of State misdirected himself by holding that a condition requiring demolition of a building could not be attached to a use permission does not appear to me established.

If in the circumstances of this case the condition imposed was not, in the Secretary of State's opinion, fairly and reasonably related to the permission granted, the courts cannot interfere with his conclusion unless it is established that he misdirected himself or reached a conclusion to which he could not reasonably have come. That has not been done." [601C-D]

72. In Elmbridge Borough Council v Secretary of State for the Environment & Hill Samuel [1989] JPL 277 the judge considered whether there was power to impose a disputed condition. The case concerned the occupation of a three-storey building for offices. Permission was granted in 1979. Condition 3 provided that the building should not in the first instance be occupied except by the Department of Health and Social Security. As part of the approval of minor alterations to the building the planning officer suggested that windows to the eastern elevation be obscurely glazed but no condition was imposed. The building was completed in 1983 and the windows were not obscurely glazed. By that time the Department of Health and Social Security did not wish to occupy the building. Case Poclain Corporation Limited became prospective occupiers. They applied for variation of the planning permission which was granted to enable them to occupy the building but it also required that the windows on the relevant elevation be obscurely glazed. Case Poclain occupied the building without changing the windows. An enforcement notice was served requiring the windows to be obscurely glazed and an appeal was made against that requirement. The learned judge found:

"So it is quite definite on the facts that the requirement of obscure glass was not brought about by the proposed occupation by Case Poclain. There was no power to impose a condition which was not fairly and reasonably related to the proposal which was permitted."

73. Delta Design (supra) concerned the change of use of a listed building. A condition attached to the planning permission required that a section of the main barn occupied as part of the development was to be demolished within two years. The time for demolition was later relaxed. The appellant sought to retain the section of the barn and to vary or remove the condition requiring its demolition. The application was refused and went to appeal. The appellant applied to quash the inspector's decision on the basis that the original condition was unlawful because it did not fairly and reasonably relate to the permitted development. At first instance the judge held that the condition was justified as being one related to the permitted development and it was open to him to decide that question as purely one of law. The Court of Appeal disagreed. They held that it was not open to a judge to decide an issue of lawfulness of a planning condition himself in circumstances where an inspector had jurisdiction to determine that issue. In that case the judge had been wrong to decide that issue himself and hold that any defect in reasoning, if there was one, was irrelevant because he could determine the matter.
74. In Carter Commercial (supra) the Court of Appeal considered a case about flooding. The issue was whether the Council could insist on a flooding mitigation scheme which would not merely prevent the appeal site from flooding but which would also resolve a long-standing flooding problem on the A362 at a junction of Rodden Road. Buxton LJ found:

"16. …First, reduction of flood risks is not an end in itself, but is in order to permit development without causing flooding off site. But the resolution of the Rodden Road problem does not, and is not necessary in order to, permit the development of the site to go forward without causing flooding elsewhere. As I believe the inspector to have found (and if he did not find, it stands out as being the case), the Rodden Road works do not and cannot affect the impact of the development on off-site flooding.

17. Second, I do not accept the argument that flooding at Rodden Road 'affects the site' because it causes, or may cause, danger to people coming to the site…"

75. Ward LJ said at [45]:

"45. The first question which obviously arises is, what is the meaning of the words 'for the purposes of flood prevention'? Do they mean flood prevention on site or do they mean flood prevention on site as well as off site. In my judgment, the natural meaning of those words is flood prevention on this particular site for which permission is sought and given. It is not a natural extension to cover flood prevention on the A362, some hundreds of yards down the road, or even flood prevention works in the road just outside the boundary of the property."

All judges agreed that the reference in the condition was to onsite works.

76. Applying that jurisprudence to the instant case the question here is, first, whether the condition imposed fairly and reasonably related to the development permitted? The answer to that is straightforward: it did. "To prevent flooding" is similar to the wording in Carter Commercial. That could apply to on or off site risks. The wording could be seen as being equally consistent with either. However, the other conditions which wrap-around condition 15, namely 14 to 18, relate to the proposed development and other onsite issues. They are part of the context within which condition 15 is to be read and a sensible and reasonable interpretation reached. That being the case and subject, as I have said, to a proper understanding on the part of the defendant as to sustainable drainage principles the defendant's approach to the condition was perfectly justifiable.
77. In terms of policy the NPPF was in force when planning permission was granted. Paragraphs 203 to 206 set out guidance on planning conditions and obligations. The test for the imposition of valid conditions are set out in paragraph 206:

"206. Planning conditions should only be imposed where they are necessary, relevant to planning and to the development to be permitted, enforceable, precise and reasonable in all other respects."

Paragraph 203 deals with what should be the approach of local planning authorities in determining planning applications where there is a flood risk:

"203. Local planning authorities should consider whether otherwise unacceptable development could be made acceptable through the use of conditions or planning obligations. Planning obligations should only be used where it is not possible to address unacceptable impacts through a planning condition."

That advice makes it clear that there is no obligation on a developer to correct a pre-existing problem which is totally unrelated to the development which the developer is proposing.

78. At the time of the imposition of the condition paragraph 21A-004 of the NPPG was a material consideration. In response to the question posed "does the condition fairly and reasonably relate to the permitted development?" it said:

"A condition cannot be imposed in order to remedy a pre-existing issue not created by the proposed development."

79. The NPPG provides some guidance on sustainable drainage principles which I have set out above. There is reference within those paragraphs to steps being taken "in line with other policies". Those other policies include the tests set out for the imposition of valid conditions.
80. In force at the time of the imposition of the condition was PPS25: Development and Flood Risk Guide. That contained guidance about sustainable drainage systems at 5.3, 5.9, 5.10 and 5.11.
81. For completeness Circular 11/95 was also in force at the time of grant of planning consent. Paragraph 25 reads:

"25. Thus it is not sufficient that a condition is related to planning objectives: it must also be justified by the nature of the development permitted or its effect on the surroundings. For example, if planning permission is being granted for the alteration of a factory building, it would be wrong to impose conditions requiring additional parking facilities to be provided for an existing factory simply to meet a need that already exists, and similarly wrong to require the improvement of the appearance or layout of an adjoining site simply because it is untidy or congested; despite the desirability of these objectives in planning terms, the need for the action would not be created by the new development. Nevertheless it is proper for conditions to secure satisfactory access, for example, or parking facilities, genuinely required by the users of the proposed development. Conditions can also be proper where the need for them arises out of the effects of the development rather than its own features; where a permission will result in intensification of industrial use of a site, for instance, a condition may be necessary requiring additional sound-insulation in the existing factory buildings. It may even be justifiable to require by condition that an existing building be demolished-perhaps where to have both would result in the site being over-intensively developed."

82. It is clear from the policy advice that there is no basis for imposing what might be an open-ended obligation on the developer to remedy a pre-existing problem in any of the policy that was contemporaneous at the time of either the grant of consent or the discharge of the condition. Only if a pre-existing problem was exacerbated by the development would it be right to impose some liability on a developer and, even then, only such liability that would relate to the degree of exacerbation created by the proposed development so that the test of fairly and reasonably related was met.
83. The Flood and Water Management Act 2010 is not wholly implemented. Schedule 3 which contains in paragraph 2 a meaning of sustainable drainage is not in force.
84. The claimant contends that the references in paragraph 2 of Schedule 3 at (a) and (c) to reducing damage from flooding and protecting and improving the environment mean that there is a positive obligation on the part of a developer to consider making improvements. In other words the situation is more than nil detriment but, under sustainable drainage principles, one of betterment.
85. A drainage system is defined in paragraph 1 as a structure designed to receive rainwater except (a) a public sewer or (b) a natural watercourse. If the schedule were in force it could apply to swales and the detention basin but it would not apply to the natural watercourse. The schedule would, therefore, be of limited application. The purpose of the Act is to establish a SUDS approving body and a separate and parallel system to the planning regime albeit there are provisions within the main Act which allow for a combined application. It is not a statutory provision that can simply be read across to a planning decision. I do not find it of any great assistance in interpreting "sustainable drainage principles".
86. The Sustainable Drainage Newsletter issued in July 2014 spoke about deferral of the implementation of schedule 3. The court was told that the situation has now changed. It is, therefore, entirely possibly that schedule 3 may never be brought into force. In those circumstances it would not be wise to place any reliance upon it.
87. The other document relied upon by the claimant is the Sustainable Drainage Consultation Document 2011. It is accepted that that has been superseded. In any event it is a consultation document, as is its replacement and, again, because of that it would not be wise to place reliance upon either of them.
88. It follows that there is nothing to show that the way that the defendant approached the discharge of condition 15 was unlawful in the sense that no reasonable local planning authority could have so concluded. The approach in the FRA and its addendum was scrutinised by the defendant's officers and there is nothing to show that they misdirected themselves in the application of sustainable drainage principles.
89. There are two further matters. First, there is before the court a witness statement from Nigel Baines. He is the Director of Eastwood & Partners with responsibility for the drainage scheme on the part of the interested party. His witness statement records that the watercourse leaves the site at the northern boundary and flows through adjacent gardens towards Dicks Garth Road where the watercourse is culverted below ground. The section flowing through the gardens restricts the flow due to reduced gradient and other factors and is therefore vulnerable to flooding during severe storm risk. After the development the surface water runoff from rain falling on to the site will be transferred to the new drainage system and will not discharge to the watercourse running through the site. The outfall from the new drainage system will be connected to the detention tank shown on the drawings submitted to the defendant. By providing storm water storage for a one in one hundred year plus climate change event whilst limiting the rate of outflow to that generated by a one in one year event flood risk is inherently reduced. The addition of substantial storage capacity within the site will provide containment and attenuation that currently does not exist.
90. Discharge from the new positive site drainage system will be via a new sewer requisition from Yorkshire Water and connected to the culverted watercourse in Dicks Garth Road downstream of and, therefore, bypassing the offsite existing gardens section that causes current flooding problems.
91. As a result, the system has been designed so that there is improvement of the drainage situation with the proposed development if that has to be demonstrated. That is what was said in the letter dated 18 September 2014 from the defendant.
92. Second, during argument the claimant amended its position to submit that the sustainable drainage system imposed a duty on the local planning authority to consider improvements. It may be that those improvements could not always be realised but the consideration of sustainable drainage principles was a necessary step which had to be embedded in the decision making process. I reject that submission as applicable in each and every case. First, there is no legal basis for it and none was suggested and, second, there is no policy or other guidance which suggests that is to be the case. However, in the circumstances here, the defendant clearly did address its mind to improvements and thus accorded, in its decision making process, with the approach advocated by the claimant.
93. In the circumstances and for all of those reasons this ground fails.

Ground 2: Did the Defendant Make an Error of Fact in Approving the Scheme to Discharge Condition 15?

94. The claimant contends that there is an obligation on a local authority in litigation to assist the court with a full and accurate explanation of all the relevant facts: see Secretary of State for Foreign and Commonwealth Affairs v Quark Fishing Limited [2002] EWCA Civ 1409 where Laws LJ said at [50]:

"…there is – of course – a very high duty on public authority respondents, not least central government, to assist the court with full and accurate explanations of all the facts relevant to the issue the court must decide. … If the court has not been given a true and comprehensive account, but has had to tease the truth out of late discovery, it may be appropriate to draw inferences against the Secretary of State upon points which remain obscure."

95. The defendant had said that there was no change to the quantity of flow or discharge point in its letter of 28 August 2014. In fact, the claimant understood there would be an increase of flow through the watercourse but no matching improvement of carrying capacity downstream of the culvert.
96. The defendant, in its summary grounds of resistance and in the first witness statement of Mr Norfolk dated 16 October 2014, said that there would be excavation. Such excavation as there was was to be upstream of the new culvert. The letter written by the defendant to the claimant on 28 August 2014 should have clearly told the claimant what the position was. The defendant now accepts that what it said on 28 August 2014 was in error.
97. The claimant had asked which documents were relied upon and had been referred to drawing 3086/26C. The position must be that the defendant was unaware of the excavation required. If it had been aware then it would have said so. The claimant was not referred to document 3086/66E until later. What is shown in that drawing forms the basis for the amended statement of facts and grounds.
98. Mr Norfolk's first witness statement of 16 October 2014 said at paragraph 4:

"The geometry of the watercourse within the site will be unaltered apart from an approximate length of 14 metres within the site. 12 metres of this alteration will be in the form of the installation of a precast concrete culvert. Approximately a further 2 metres upstream of the culvert will be engineered to facilitate the construction of the culvert structure and associated retaining walls to support the new estate road. Upstream of these works the eastern bank of the watercourse will not be altered and therefore the overtopping regime of this bank will remain as before."

The claimant submits that that shows that the defendant made its decision to discharge the condition on a false basis. Mr Norfolk did not say that he misunderstood the position and, therefore, he must have been unaware of the position at the relevant time.

99. The second witness statement of Mr Norfolk dated 30 April 2015 the claimant submits shows him trying to qualify what he had said earlier. If the claimant was wrong to place reliance on what the defendant had said earlier, in the email of 28 August 2014, then the claimant would have expected the defendant to alert the claimant to the position to make it clear that it was aware of the excavation. In the absence of that, the inference is that the defendant's letter said what it meant, i.e. that there was no excavation at all. Little reliance can be placed on Mr Norfolk's second witness statement because it is after the event and, in any event, does not address the implications of the 2 metre excavation.
100. Although Professor Rhodes had obtained a joint report from Professor Pourkashanian and Professor Ingham to supplement his statement the claimant accepts that it is not directly relevant to the narrow point of ground 2. The claimant accepts now that there is limited additional excavation. The issue is whether the defendant knew that at the time of making its decision.
101. The defendant refers to the chronology set out above and, in particular, points out that drawing 30864/026C shows the culvert and references drawing 30864/066E for details of the culvert inlet and highway retaining wall. An examination of those documents clearly shows the position with regard to excavation.
102. The claimant's solicitors by 15 September 2014 were aware of drawing 66E because that was referred to in the FRA addendum of January 2014.
103. The defendant's correspondence with the claimant has to be seen in the context of the allegations that the claimant was making at the time. Those allegations have changed over time. The responses which the defendant sent were dealing with the allegations made to it at the time and which were that what was proposed made the situation worse.
104. On 24 September 2014 the defendant's response was to allegations that there was to be an excavation of five-sixths of the watercourse. At that time the claimant's case was that the works would make the existing flooding situation worse. The excavation which the claimant understood to be required was material because the claimant understood that it would affect the flow of water.
105. The defendant did not expressly point out the additional 1.8 metres affected by excavation required to install the new culvert. However, Mr Norfolk's first witness statement had drawn attention to what would happen. He did not say that he was aware of the excavation at the time but did spell that out in his second witness statement.
106. Mr Norfolk's scrutiny of materials submitted by the interested party was thorough. He had asked for further calculations and material. That was supplied in the January 2014 addendum. By March 2014 he was still asking for further information. It is clear that he was not easily satisfied. The concept, therefore, that he would have been unaware of the additional excavation is not credible.
107. The inter-departmental consultation response of 23 December 2013 of Mr Norfolk to development services shows that he was asking for calculations to show the development surface water drainage system was designed to accommodate a one in one hundred year plus climate change event. He was also seeking calculations and construction details to show the size of the new culvert beneath the access road as adequate in those circumstances. The addendum in January 2014 provided that detail and illustrates the thorough nature of the approach which Mr Norfolk took.
108. The witness statement of Nigel Baines deals with the two drawings of concern to the claimant, namely 26C and 66E. It says:

"25. Reference has been made in the original Detailed Statement of Grounds of Claim and Statement of Facts document submitted by the Menston Action Group to a proposal. It is said, shown on the Eastwood and Partners drawing 30864/026C …… for the existing watercourse to be excavated over the majority of its length but not over the remainder. The effect, it is said, would be to increase the capacity of the upstream section above the road crossing but not below it, which it is stated by the Claimant would direct more water to the bottom of the site and reduce the length of the escape boundary.

26. However, drawing 30864/026C does not show an excavation of the watercourse along the watercourse upstream of the road crossing as claimed and there is no proposal to do so. What is shown on the drawing are details for the proposed 1200 mm culvert crossing under the road over a relatively short length of about 12 m. The invert level of the culvert is to be set lower than the stream bed level. The culvert is shown at a lower level so as to provide sufficient cover to the road, but also to allow it to silt up in line with the existing watercourse profile, which indeed is clearly shown on drawing 30864/026C in the bottom right section drawing of the culvert. The effect will be to present a channel after siltation, similar to the profile of the existing watercourse. The drawing clearly shows the bed/silt level through the culvert and it is to be assumed that the objectors' interpretation is based on a misreading of the drawing.

27. Regarding the length of the escape boundary, if the act of developing either side of the watercourse were to channel flows towards the northern boundary, the proposal outlined at paragraph 26 above, and detailed in the response to Planning Condition 15, is to capture and direct escape flows to the enlarged field storage area referred to. A principle in this proposal is to maintain the water course level/gradient, and bankside overspill areas as they are at present, to provide a 'sustainable' solution.

28. In the amended Claim dated 2 October 2014, the Claimant has made reference to drawing 30864/066 Rev E (which was already in the bundle at page 171) and various levels have been highlighted. The main purpose of this drawing is to show details of the proposed highway retaining wall at the position of the culvert under the proposed road. The drawing shows construction details which, local to the culvert, indicate a dip at the culvert entrance. This is necessary to facilitate installation of the culvert, over a distance of approximately 1.80 m upstream of the culvert inlet. The result, immediately after construction will be a localised dip at the culvert entrance, which in itself will not affect the issue under consideration.

29. In the longer term, the culvert is expected to partly silt up from the base as indicated in the section on drawing 30864/026C (Tab 14) of the Claimants Bundle) and a depth of 250 mm has been allowed. The siltation is not shown on drawing 30864/066E because that is not the purpose of that drawing. It is not expected that any local increase in flow capacity at the culvert entrance will adversely affect flood risk downstream, which will be more than compensated for by the swales upstream of the site, the potential for overspill to be carried to the enlarged field storage area and reduction in direct discharge from the site are itself. Purely from a hydraulic capacity point of view there should be no material new increase in flow by lowering the culvert inlet, because the culvert gradient will reduce correspondingly to tie in with the existing watercourse level downstream (less approximately 250 mm to allow for siltation), and the overall hydraulic gradient will remain as it is at present. It is not possible to predict exactly the length of time it will take for the culvert invert to silt and neither is it possible to say with certainty the final extent of siltation. Even without siltation, the part of the culvert lying below the gradient line between the bed level downstream and the bed level upstream represents, more or less, a 'dead' area from a flow capacity point of view."

The witness statement, therefore, shows that the excavations required at the level of the culvert and beneath it make no difference to the flow of water.

109. The later report obtained by Professor Rhodes is not relevant as it is not done on the appropriate basis.

Discussion and Conclusions

(i) Application to Call Mr Norfolk for Cross-Examination

110. Almost at the very end of Mr Wolfe's reply he made an application to cross-examine Mr Norfolk about his state of knowledge at the relevant time. It is fair to say that the application had been foreshadowed in correspondence before the hearing and Mr Norfolk was present at the hearing in case the application was made. However, no application was made at the beginning or during the hearing until, as I have said, the end of the claimant's reply.
111. The matter arose then because the prospect was raised as to the claimant's position if it was possible that I might make a certain factual finding. I put Mr Wolfe to his election as to whether he was making an application to call Mr Norfolk for cross-examination. He said that he was and duly made the application.
112. The application was opposed by Mr Fraser QC, acting on behalf of the defendant. Mr Wolfe contended that what Mr Norfolk said in his second witness statement was in conflict with what the defendant had said in its earlier correspondence. The defendant said that there was no conflict at all. Self-evidently the culvert would need to be tied in. The application was extremely late.
113. I ruled against Mr Wolfe on the basis that it was exceptional for cross-examination to take place in a judicial review hearing, and that I had sufficient factual material upon which to make a determination without hearing oral evidence.

(ii) Merits of Ground 2

114. I have paid no attention to the report from the two professors obtained by Professor Rhodes. It was obtained after the event, there are question marks about whether it is carried out on the correct basis but, most materially, it deals with an assessment of the discharge scheme on its merits which it is not the role of the court to deal with.
115. In their letter of 7 August 2014 the claimant's solicitors, Schofield Sweeney made it very clear that the drainage scheme submitted by the interested party, in their view, would cause considerable additional flooding in long established properties as well as rendering the existing culvert in Dicks Garth Road inadequate. That was the position that the defendant had to respond to at that time.
116. The Council's initial response was an email from Mr Driver on 13 August 2014 in which it said, inter alia, that the Council was satisfied that the developer of the Derry Hill site had provided satisfactory information, something reflected in the Environment Agency's response to the planning application.
117. The claimant then asked for further detail in its letter 21 August 2014 but retained its concern that the problem was that there was insufficient capacity to accommodate the water flow such that there would be considerable additional flooding at Moorfield Avenue and the surrounding area. It was contended on behalf of the claimant that it would be irrational to discharge condition 15 in response to the submitted scheme. The claimant's solicitors continued to ask for full and frank answers to their previous questions and reserved the right to challenge the decision of 15 August 2014.
118. There then followed the detailed email from Mr Driver of 28 August 2014 the terms of which are set out above. It made it clear that there would be no worsening of the existing flood risk or the creation of any new flood risk.
119. The identification of the documents relied upon by the defendant was asked for on 2 September 2014. Mr Driver emailed the following day referring to 30864/026C which was available on the planning portal.
120. In Schofield Sweeney's following letter of 15 September 2014 they referred in terms to the Eastwood & Partners' addendum report of January 2014 and the plans/drawings and supplementary documents as part of that. It is evident, therefore, that from that time the claimant was aware of the documents relied upon by the defendant and had the ability to inspect those documents and, indeed, appears to have done so.
121. For reasons which are not at all clear given what the drawings show on 22 September 2014 Schofield Sweeney were under the impression that the watercourse running through the site was to be excavated up to the point of the new 1200 millimetre culvert under the new access road.
122. The claimant contends that paragraph 5 of the email of 24 September 2014 where the defendant said that the approved proposal did not involve the excavation of the existing watercourse to alter its existing alignment or profile up to the point of the new 1,200 millimetre diameter culvert showed that the defendant did not understand the position.
123. As the plans show and, as the claimant now accepts, there is a tie in of about 1.8 metres to allow the new culvert to be installed in the site. I find it inconceivable that any reasonably competent drainage engineer examining the submitted plans and reading the addendum of January 2014 from Eastwood & Partners would be unaware of what the drawings showed.
124. Further, the evidence is that Mr Norfolk was thorough in the way that he dealt with the discharge of condition 15. The email that he sent to his departmental colleagues of 23 December 2013 shows that he wanted further information before being prepared to discharge the condition. He received the information in January 2014 but continued asking, or getting members of his staff to ask, Eastwood & Partners for further details before being able to advise that the condition could be discharged.
125. Although the defendant did not say in terms that it was aware of what the plans showed it did refer the claimant to the plans and did correct the claimant's misunderstanding that the watercourse upstream of the culvert onsite was to be excavated in its entirety. Read literally the email of 28 August might be interpreted as there being absolutely no excavation up to the point of the new culvert. However, in my judgment, it would be irrational to do so. Any reasonable reader would understand that the culvert had to be tied in and would consult the relevant plans. Those plans clearly show what was intended by way of installation of the culvert. In those circumstances I am unable to draw the conclusion that the defendant was unaware of the situation.
126. Equally, I am satisfied, on the exchange of correspondence which I have seen, that the defendant sufficiently discharged its duty and provided the claimant with an accurate explanation of the facts relevant to the issue which the claimant's solicitors were then pursuing.
127. Further, it is clear from paragraph 4 of Mr Norfolk's first witness statement that he was very much aware that the geometry of the watercourse within the site was unaltered apart from about 14 metres; 12 metres for the instillation of the culvert and a further 2 metres or so to facilitate the construction of the culvert structure. All of the contemporaneous documentary evidence points towards a conscientious drainage engineer testing what was submitted to him on behalf of the interested party.
128. In fairness to the claimant I have discounted Mr Norfolk's second witness statement. I conclude on the basis of his first witness statement and the contemporaneous documents that the defendant discharged the condition on a proper understanding of the circumstances based upon information supplied in the addendum to the flood risk assessment of January 2014, its accompanying documents and plans and later information received from the interested party.
129. In the circumstances ground 2 fails.

Standing

130. The defendant raised whether the claimant had appropriate standing to bring the judicial review action.
131. The Menston Action Group is a community group made up of residents of the Menston area. They are very concerned about flooding in Menston and fearful that the existing situation will be exacerbated by developments in their area of which the development at Derry Hill was one. Various of the residents I was told lived in the immediate vicinity of the proposed development.
132. I am quite satisfied that the claimant has a real and genuine interest in obtaining the relief which they seek. The claimant clearly has a genuine concern for the environment and has a genuine interest as local residents. There is nothing to suggest that the claimant is anything other than a responsible local group. In those circumstances, I have no hesitation in finding that the claimant has sufficient interest to bring the claim.
133. Notwithstanding that, for the reasons which I have set out above, this claim is dismissed.