AGENDA ITEM 6.1 DR/03/17 committee DEVELOPMENT & REGULATION date 27 January 2017 COUNTY COUNCIL DEVELOPMENT Proposal: Construction of a flood alleviation scheme consisting of an attenuation bund (127m in length and maximum 1.2m height above ground level) with culvert through Prittle Brook and temporary attenuation area in the event of flooding, with construction and maintenance access via an existing track off Rayleigh Road Location: West Wood (Ancient Woodland), East Thundersley, Essex Ref: CC/CPT/42/16 Applicant: Essex County Council, Local Lead Flood Authority Report by Acting Head of County Planning Enquiries to: Gráinne O’Keeffe Tel: 03330 133055 The full application can be viewed at www.essex.gov.uk/viewplanning Reproduced from the Ordnance Survey Map with the permission of the Controller of Her Majesty’s Stationery Office, Crown Copyright reserved Essex County Council, Chelmsford Licence L000 19602 1. BACKGROUND There is no relevant planning history on the site. 2. SITE The development site area is stated as 2.5ha, located within West Wood (an ancient woodland of circa 32ha), in Thundersley in the District of Castlepoint. The site is located within the Metropolitan Green Belt. The site is allocated as Public Open Space in the CastlePoint Proposals Map adopted 1998. Bridleway PROW BENF_85 runs parallel to the northern end of the development site boundary and north of Prittle Brook. The site is located within Flood Zone 1, as per the Environment Agency website, an area of low flood risk. There is an existing pedestrian gate for public access from Rayleigh Road (A127) and an existing gated vehicular access for maintenance vehicles. The nearest residential properties are located on Prittle Close and Rayleigh Road and adjoin the western site boundary. 3. PROPOSAL The proposal is for the construction of a flood alleviation scheme consisting of an attenuation bund 127m in length and maximum 1.2m in height above ground level. The bund would be constructed from imported inert soil and located on the route of the existing track through the woodland, reducing in height and merging with existing ground levels at the margins. A clay core is also proposed underneath the proposed soil bund, to ensure structural stability of the bund. The clay core would ensure that lateral movement of water does not occur though the bund. The clay core would be excavated to a maximum of 1m deep by 1m wide and would run the entire length of the bund. The clay material proposed for the core is also proposed to be inert. A culvert 900mm diameter over a distance of 16.2 metres is proposed for Prittle Brook. The temporary attenuation area indicated to the west of the proposed bund would hold water in the event of flooding for up to 48 hours, the proposed storage capacity is 15,300m³. The construction and maintenance access is proposed via an existing access and track off Rayleigh Road. The overall objective of the Flood Alleviation Scheme is to reduce flood risk to people and properties in the Critical Drainage Area of East Thundersley. 4. POLICIES The following policies are of relevance to this application: National Planning Policy Framework (NPPF), DCLG March 2012 Section 9: Protecting Green Belt land Section 10: Meeting the challenge of climate change, flooding and coastal change Section 11: Conserving and enhancing the natural environment Section 12: Conserving and enhancing the historic environment Castle Point Draft New Local Plan 2016 (not yet adopted) submitted for Examination on 25 th August 2016. (The latest update is a letter from the Inspector to Castlepoint dated 05/01/2017, notifying the District that the duty to co-operate has not been complied with) Paragraph 216 of the NPPF states, in summary, that decision-takers may also give weight to relevant policies in emerging plans according to the stage of preparation of the emerging plan; the extent to which there are unresolved objections to relevant policies; and the degree of consistency of the relevant policies in the emerging plan to the policies in the NPPF. Having regard to the Inspectors letter dated 05/01/2017 recommending non- adoption of the New Local Plan under Section 20(7A) of the 2004 Act, and in this situation the PPG advises that the most appropriate course of action is likely to be for the local planning authority to withdraw the plan under Section 22. Therefore at this stage no weight has been given to the Castle Point Draft New Local Plan 2016. Castlepoint Local Plan (adopted 1998, saved 2007) Paragraph 215 of the NPPF states, in summary, that due weight should be given to relevant policies in existing plans according to their degree of consistency with the Framework. An NPPF Consistency Check was published by the District on 2 nd April 2013. It compares each of the saved policies in the Castle Point Adopted Local Plan 1998 with the NPPF, and indicates the degree of consistency between the two documents. Where necessary it indicates where additional consideration should be given to policies in the NPPF in order to ensure that decisions reflect the Government’s planning objectives and presumption in favour of sustainable development. The relevant policies that are consistent with the NPPF are listed below. Policy EC7 Natural and semi-natural features in urban areas (Policy EC7 is generally consistent with para 74 of the NPPF. However, consideration should be given to those exceptions listed in para 74 when consideration applications for development on open spaces.) Policy EC22 Retention of Trees, Woodland and Hedgerow Policy EC38 Archaeological Sites and Monuments Policy RE12 Public Rights of Way Essex Replacement Waste Local Plan (Pre-submission Draft March 2016) Policy 13 Landraising Other Documents Natural England and Forestry Commission ‘Standing Advice for Ancient Woodland and veteran trees’. 5. CONSULTATIONS CASTLEPOINT BOROUGH COUNCIL PLANNING – no objections in principle to the proposals. In summary, hope there is satisfactory technical evidence demonstrating the adequacy of the scheme in surface water drainage terms, particularly covering the point that betterment in this location does not create problems elsewhere. Also trust that that there would be no adverse effect on matters of nature conservation interest, given the ecological sensitivity of the site concerned. ENVIRONMENT AGENCY – The EA responded to inform the Planning Authority that they should not have been consulted as it is for a proposal that does not appear on the DMPO. They stated the description of the area as having critical drainage problems has been applied locally and not as a result of any notification from the EA. (Note: Notwithstanding the fact that the EA is not a statutory consultee on this application under the DMPO, as this is an Essex led development, the County Planning Authority has subsequently requested impartial advice from the EA – if received, this will be reported orally at Committee) LOCAL LEAD FLOOD AUTHORITY – No objection We have received a request to comment since this is a major development. However, our criteria are that we can provide comments where impermeable areas are greater than 100m2. Therefore, this would not usually meet our criteria for comments. We are commenting since we have received a specific request from the case officer including some specific questions, responses to which are outlined here, and in our wider remit as LLFA to manage flood risk from local sources. Having reviewed the Planning Statement and the associated documents which accompanied the planning application, we do not object to the granting of planning permission based on the following: Based on Figures 5 & 6 of the Planning Statement it appears that flood risk is only increased in the woodland behind the bund where water is proposed to be attenuated. The light blue areas in the urban area to the west of the wood, which are assumed to be the deepest areas, are removed in the post-scheme scenario. This is confirmed by Section 5.2 of the Planning Statement which states: ‘The height of the bund was limited by ground levels of properties upstream. The spillway heights and lengths had to be set to maximise the amount of storage provided while not increasing water levels upstream, which required an iterative process .’ In considering alternative options, the planning statement says at 3.2 that other measures such as increasing pipe size, flow diversion and small scale attenuation features have been determined as ineffective in reducing the risk to properties. The most effective method is to attenuate water upstream by intercepting key flow paths in available open space. Four potential bund locations were identified and the bund at land behind Queensmere was determined to no longer be feasible due to approval of a planning application at that location. The 3 proposed bunds are therefore the only locations where the flowpaths can be suitably intercepted to significantly reduce flood risk. A smaller bund could perhaps be located further west on the southern flowpath (landowner/other constraints permitting) but this would not attenuate as much flow as the proposed Bund 3 since the current bund is at the location where both flowpaths converge. Bunds were not considered east of West Wood since the restriction at the culvert behind properties at Westbourne Close is what causes the Prittle Brook to flow out of bank and form a flow path through residential areas which causes flooding (as mentioned in 3.1.1). I have also had regard to the ‘East Thundersley Flood Alleviation Scheme Flood Risk Assessment’. This explains the modelling methodology which appears acceptable. It should be noted that the mapping included showing pre- and post- scheme flood depths is based on three bunds not just the one subject to this planning application. However, as also confirmed in Table 2 of this report Bund 3 only will result in properties being removed from being at risk during varying return events and will not increase flooding at upstream and surrounding properties.