Guidance for architects, and developers on flood risk, drainage and phase 1 contaminated land reports is summarised below with links to the key summary documents.
Past industrial history has left some areas of land with an inheritance of contamination. This can include contamination of soils by chemicals or other hazardous substances, migration of contaminants to groundwater and surface waters and the production of hazardous gases from decomposing organic material in landfills etc.
A legacy of contamination can also be left by processes that are carried out on sites that are not normally considered as ‘industrial’ (e.g. farms, stables & kennels etc.). Part 2A of the Environmental Protection Act 1990 aims to ensure that following development, the final condition of the land will prevent it being designated as contaminated at some future point.
Local guidance should be read in conjunction with DEFRA & the Environment Agency’s Model Procedures for the Management of Land Contamination (CLR11) and the National Planning Policy Framework (NPPF, 2012).
The Council’s requirement to characterise the site for contamination will be proportionate to the risk of harm perceived in the light of information available. Therefore, for all proposed residential developments, a minimum of a contaminated land Phase 1 desk study report must be submitted in support of the planning application.
A basic contaminated land search without any interpretation (i.e. produced for property/land purchase purposes) which are submitted in isolation, will not be sufficient to provide all of the information required by Epping Forest. Epping Forest require a more detailed desktop report in the first instance, such as our Contaminated Land report. The Essex Contaminated Land Consortium has produced a general guidance document, Land Affected by Contamination, 2nd edition 2007, to assist applicants and developers of land potentially affected by contamination.
For all sites where contamination is known or there is a reasonable suspicion of contamination (either on site or sufficiently close to be potentially affected), then a Phase 2 (intrusive investigation) report and remediation statement may also be required prepared by a Competent Person with a recognised relevant qualification, sufficient experience and membership of a relevant professional organisation.
The Epping Forest brownfield land register lists sites that meet the following criteria:
Epping Forest planning policy requires that a Site Reconnaissance should be undertaken after the basic site information and basic screening data on potentially contaminating uses and environmental conditions has been obtained and examined, in order that any relevant issues requiring more detailed inspection during the site walkover can be identified.
Site Walkover checklists (examples of which are contained in Annex 1 of EA/NHBC R&D66 Annex 1 and in CLR2 volume 1) must be completed and included in the appendices of the Phase 1 report.
Epping Forest District Council (Essex)
When is a Flood Risk Assessment required? The Environment Agency provides flood risk standing advice for applicants and agents. Epping Forest District Council (EFDC) has set additional requirements for the assessment of flood risk for proposed developments, dependant on the developments’ size and location within the district.
The relevant policy is presented in Policy U2B of the Local Plan Alterations (2006). Epping Forest flood risk assessment zones FRAZs are where an FRA may still be required for development which does not match the NPPF criteria. FRAZs are defined as catchments of ordinary watercourses identified as key areas where surface water runoff is contributing to Main Rivers or areas of known historic flooding.
Within the Epping Forest Flood Risk Assessment Zones as shown on the Alterations Proposals Map, Flood Risk Assessments will be required for any development proposals (other than house extensions) which exceed 50m2. Outside these zones, a flood risk assessment will be required for any proposals which exceed 235m2. For details see section 8.2.9 of the SFRA (2015).
Climate change: For the majority of modelled watercourses within the district, detailed modelling indicates a slight increase in the extent of the 1% AEP flood outline compared to the present day, despite taking into account existing flood defences.
This is likely to be due to the absence of formal flood defences throughout a large area of the district. The most noticeable increase in the flood extent is along the Cripsey Brook flowing through Chipping Ongar and along the River Roding to the north and south of its confluence with the Cripsey Brook.
The mapping indicates a number of properties located within areas of Chipping Ongar may be at increased risk as a result of the impacts of future climate change. For this reason, recommendations require all floor levels, access routes, drainage systems and flood mitigation measures to be designed with an allowance for climate change; and the potential impact that climate change may have over the lifetime of a proposed development should be considered as part of a site-specific FRA.
The district includes a number of large main rivers and associated tributaries such as the River Lee, River Roding, Nazeing Brook, Cobbins Brook and Cripsey Brook. Waltham Abbey, Nazeing and Lower Nazeing are identified as major fluvial flood risk areas within the district. EFDC is a predominantly rural area, with approximately 92% of its area located within the Metropolitan Green Belt.
Future development, particularly that located on greenfield land, has the potential to increase surface water flooding as a result of increasing impermeable surface area. Epping have introduced a number of policies in the local plan including Flood Risk Assessment Zones which set stringent requirements, beyond those outlined in the NPPF.
Epping Forest District Council
Drainage policy is for SuDs to conform to National Standards. For greenfield developments, the peak runoff rate for the 1 in 1 year rainfall event and the 1 in 100 year rainfall event must not exceed the peak greenfield runoff rate. For developments which were previously developed, the peak runoff rate must be as close as reasonably practicable to the greenfield runoff and should never exceed the rate of discharge from the development prior to redevelopment for that event.
See Epping Forest SFRA (2015). Epping Forest DC are taking a proactive approach towards surface water flood risk management, setting out when and where proposed development should be accompanied by a site-specific FRA and surface water management strategy.
Epping Forest District Council
There are 23 incidences of groundwater flooding reported in the SFRA (2015). Almost the entire district is underlain by London Clay or Claygate Member bedrock. Perched water tables may occur at the boundary between permeable deposits and the underlying clay/mudstone, with springs where the boundary is exposed.
The south and south-west of the district is underlain by impermeable soils which are seasonally waterlogged. Areas where the potential for groundwater flooding to occur at the surface largely correspond with areas of Alluvium and Head deposits associated with the Main Rivers located within the district such as the River Lee and River Roding.
Groundwater levels may rise in response to high river levels or tides. Areas where there is potential for groundwater flooding to occur, include areas around Epping Green, a band stretching across Epping Forest, Epping and Coopersale and around Stapleford Abbots and Abridge. These areas correspond with underlying Claygate Member bedrock geology.
Groundwater flooding is known to occur around Nazeing associated with outcrops of the highly permeable Lambeth Group sands and the Kesgrave Sands and Gravels. Groundwater flooding incidents within the district are limited and where they have been recorded to occur, they are concentrated within urban areas of Epping Forest, specifically Chigwell, Loughton, Theydon Bois and Epping.
The Epping Forest Planning Map allows you to see the planning history of a property or site from planning records from 1948 to the present day.