Appeal 6003866

The appeal is dismissed.

On my site visit I observed 6 lodges positioned adjacent to the lake and two other buildings to the southern part of the site.

The main issue is whether the variation of condition 9 is appropriate having regard to flooding.

The appeal site is located within [name] 3 and being located within the [name] is subject to tidal flood risk. As such it is categorised as having a high probability of flooding.

The site lies in proximity to the [name] (a designated [name] with fluvial influence), the [name] (Haven) (a designated [name] with fluvial and tidal influence) and The Wash (tidal influence). The site is afforded protection from raised flood defences. Nevertheless, the primary risk to the site is a breach in defences.

Sites used for holiday or short-let caravans and camping, subject to a specific warning and evacuation plan are classified as ‘more vulnerable’ development.

Policy 4 of the South East Lincolnshire Local Plan 2019 (LP) restricts the occupancy of caravan, chalet, log cabin, camping and touring sites at risk of tidal flooding between 1st November in any one year and the 14th March in the succeeding year. The original permission was subject to a holiday occupation condition to this effect to make the development acceptable. The proposal seeks to vary the condition to allow the holiday accommodation to be available for year-round until 31 December 2049 and that from 1 January 2050 onwards, no unit shall be occupied between 1 November in any year and 14 March in the succeeding year.

The appellant asserts that LP policy 4 is out of date. However, Environment Agency (EA) analysis1 of actual historical recorded data for the components most likely to cause tidal inundation clearly shows an increase in occurrence for the months of November to March and that balancing the flood risk with the key local economic drivers of October and Easter school holidays, the current occupancy restriction is considered to be the appropriate period. Consequently, an occupancy restriction is considered as an essential mitigation measure, from a very limited suite of mitigation tools available to these types of development. I therefore do not concur that the Policy is out of date or inconsistent with the flood risk aims of the National Planning Policy Framework (the Framework).

All-year-round occupancy, until 31st December 2049, is sought following construction of the development due to site level changes which the appellant submits mitigates flood risk at the site and allows for safe occupation of the lodges for a further 25-years. Amongst other things, they cite the reference to the [name] & Evacuation Plan covering the site and the presence of a site manager to oversee any necessary evacuation. Whilst circumstances may change after the condition is set the key test for amending the condition is whether it is still pertinent and necessary to make the development acceptable.

Due to their temporary nature, lodges such as these, are more vulnerable and susceptible to the consequences of flood risk as they become unstable during flooding, putting future occupiers at significant risk. Planning Practice Guidance (PPG) in respect of [name] and [name] explains that the Framework sets strict tests to protect people and property from flooding.

The Framework makes it clear that local planning authorities should take full account of potential climate change impacts. Furthermore, paragraph 164 a) sets out that new development should be planned for in ways that avoids increased vulnerability to the range of impacts arising from climate change.

The Framework refers to [name], which are shown on the [name] for Planning. This map forms the basis of identifying where flood risk should be considered as an issue and subsequently considered. It is not disputed that the [name] does not consider the presence of defences or account for climate change. Nevertheless, the EA 2006 tidal breach maps remain the best available information to inform flood risk at the site, for determining whether year-round occupation is acceptable. The hazard maps show that the appeal site has a current hazard classification of ‘Danger for Most’ (includes the general public) and could experience flood depths of 0.5-1m should a breach in the defences occur. 1 Appendix EA3 - [name] on the [name] of Historic Tide Data Background (v4 Dec 2020)

Following the excavation of the lake, site levels have been raised between 0.37- 0.63m2. Comparisons of the topographical survey3 against the EA hazard mapping data indicates that the site could still experience flood depths of up to approximately 0.63m and that lodges 1, 2 and 6 would experience water ingress. Consequently, the change in levels does not fully remove the present-day flood risk.

While the appellant does not consider this would represent an unacceptable risk of flooding the site would be inundated by floodwater and occupants could be stranded in the lodges for an unknown period of time surrounded by floodwater. The suggested raising of finished floor levels would not ensure occupants would remain safe as they would likely be stranded within the lodges, possibly without essential services including water and electricity. Furthermore, the flood depths on site would not allow the free movement of people and emergency routes may become impassable. Consequently, it would be contrary to the PPG4.

The evidence pertaining to ground and finished floor levels is for the 6 lodges currently in situ. However, planning permission5 allows for the use of 15 lodges6 and no assessment of the flood risk to the remaining lodges has been undertaken. The implications of the variation for the additional lodges are therefore not clear.

The appellant questions the reliability of the data referred to by the EA, on the basis that the mapping is approaching 20 years of age, stating that the maps pre-date the [name] and the Lincolnshire tidal defence improvements and that they fail to make allowances for climate change and that there is no historic record of flooding.

Areas benefiting from flood defences remain at risk from flooding as flood defences reduce risk but do not completely remove the likelihood of flooding, particularly in extreme weather conditions. PPG7 states that “Areas behind flood defences are at particular risk from rapid onset of fast-flowing and deep-water flooding, with little or no warning if defences are breached.” Consequently, development needs to be designed to: avoid internal flooding from residual risk from flood risk management infrastructure wherever possible; and ensure people are not exposed to hazardous flooding, irrespective of the development’s vulnerability classification. Furthermore, the Framework requires that any residual risk be safely managed and that safe access and escape routes are included where appropriate, as part of an agreed emergency plan.

The presence of the barrier reduces the probability of tidal flooding upstream, but it does not eliminate the risk of flooding altogether. The EA advise that when the barrier is raised, the dominant source of flood risk upstream of the barrier will be fluvial (from the [name]) and tidal flooding remains from potential breaches downstream of the barrier. As such, the hazard maps remain the best available information. The breach hazard maps do model the failure of the raised defences at intervals, rather than the entire failure or non-existence of the defences. 2 Table 5.1 – [name] and Site Levels Comparison of the [name] of Case 3 [name] 24-117-01 [name] inc [name] 4 Paragraph 44 reference ID:7-044-20220825 5 application reference B/21/0077 6 Attention drawn to B/21/0077/NMA - Non-Material amendment to the approved plan B/21/0077 to replace caravan lodges with glamping pods and activity pod, reduce the number of holiday units from 15 to 12, omission of internal vehicular access road and reshaping of lake – Approved 28/03/2022; 7 paragraph 042

The Appellants statement indicates that the level of risk of flooding is a 0.1% chance occurrence in the period to 2049. However, the EA confirm that the 0.1% modelling is an annual exceedance probability, presenting a 0.1% chance of occurrence in any one year for the present day and should not be considered as a 0.1% chance of occurring in the period up to 2049.

Whilst the probability of failure is low, it is not negligible or de minimus and the consequences could be significant. Seasonal occupancy remains an effective method for managing flood risk to the site.

In recognition that the site may be subject to flooding the appellant places a reliance in flood warning and evacuation measures to keep people safe, stating that the lodges are strictly for short-term rentals and that all guests have a residence they can evacuate to in the event of a flood and that occupants could take refuge at the nearby [site address] House. Adequate warning of a flood cannot be guaranteed and in the event of a breach it is unlikely to be safe to move through the water to seek refuge at this property. There is also no guarantee that this property and the holiday lodges would remain connected. Furthermore, a recent appeal8 concluded that an evacuation plan was not sufficient mitigation to ensure the safety of visitors.

It is recognised that the extension of the season for the occupation of the lodges would have economic and social benefits, in terms of the visitor economy of the Borough. However, its contribution would not outweigh the conflict identified.

My attention has been drawn to nearby sites that have been granted planning permission for static caravan pitches for holiday use throughout the year, including Meadowvale Caravan Park. [name] recognise this site is proximate to the appeal site, I have limited information before me and cannot be certain that the circumstances are directly comparable. The evidence before me indicates that two of these decisions were made under a previous local plan and before flood hazard information was available. Whilst there may be other properties within the locality subject to flood risk this does not make the proposal acceptable. In any event, I have determined the appeal on its own merits.

I have carefully considered the appellants arguments regarding their perceived low risk of flooding and the economic benefits of allowing an extended period of occupation. Irrespective of the increased ground levels and the mitigation measures suggested the risk of tidal flooding remains. This weighs heavily against the proposal. It therefore follows that the proposed variation of Condition 9 would pose an unacceptable risk to people from flooding, contrary to the flood risk objectives of the LP and Framework.

For the reasons stated, I therefore conclude that the proposal to extend the occupancy restriction would be unacceptable in flood risk terms, which draws the proposal into conflict with Policy 4 of the LP. The proposal would also conflict with the flood risk objectives of the Framework. 8 APP/D2510/V/20/3262525

Condition 9 remains reasonable and necessary and a variation to it to allow extended occupancy would present unacceptable risk in terms of flooding. Consequently, the proposal conflicts with the development plan when considered as a whole and there are no material considerations, either individually or in combination, that outweighs the identified harm and associated development plan conflict.

The appeal is dismissed.