“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.”
“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.”
“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.”
“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.”
“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.”
“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.”
“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…”
“1. The various documents referred to in my letter of 18th 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 15th 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 18th 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.”
“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.”
“Although the submissions focussed on the Sevenoaksand Hulmecases, a number of other authorities were put before me, including some that were not considered in Hulme'scase, 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'scase 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'scase, 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 Waltoncase.’” (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'scase 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'scase, 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 Waltoncase.’”
“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.” (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.”
“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.”
“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.”
“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.”
“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.” • 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.”
“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.”
“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.”
“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…”
“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.”
“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.”
“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.”
“A condition cannot be imposed in order to remedy a pre-existing issue not created by the proposed development.”
“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.”
“…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.”
“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.”
“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 dated2 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.”