The Jolly Boatman and Hampton Court Station site has been designated for comprehensive re-development since 1986 with the site's planning history going back to 1948, when a series of applications for refreshment pavilion at the Jolly Boatman site were given conditional approval.

As Plan 4 of the Development Brief, Local Plan Proposals Map extract shows, the site was not considered as lying within the then indicative (1 in 100-year) floodplain of the River Thames or the River Mole/Ember. The outline of the areas liable to flood extended alongside the edges of the rivers, with the River Mole encroaching more widely on the Cigarette Island Park than the River Thames. The Development Brief does not therefore specifically address flooding issues.

The outline of the floodplain changed recently when the EA revised their Lower Thames Flood Studies in 2004 and 2005. As a result of changes in modelling, the 1% peak flood level rose from 7.78mAOD to 8.11mAOD in September 2004 and then again to 8.41mAOD in November 2005. As a result, the current EA maps show the entire Site to lie within the high risk Flood Zone.

The site is situated in a prominent location, opposite Grade 1 listed Hampton Court Palace. The existing Hampton Court station provides the only train access to the very popular tourist attraction. However the current station, built in 1849 is in need for restoration. The refurbishment of the station is linked with development of the Jolly Boatman site, previously housing a café, now demolished. The Elmbridge Borough Council (EBC) have insisted on comprehensive approach to the development which is guarded by strict conditions outlined in the Development Brief.

Since the development is driven by the improvements to the Railway Station, it is considered that no alternative sites within Flood Zones 1 and 2 are suitable and that the Exception Test is applicable.

The Exception Test is applied after the Sequential Test where more vulnerable development e.g. residential, is proposed in Flood Zone 3A. PPS25 requires that compliance with each part of the Exception Test should be demonstrated in an open and transparent way using the following criteria set in PPS25.

For the Exception Test to be passed:

it must be demonstrated that the development provides wider sustainability benefits to the community that outweigh flood risk, informed by a SFRA where one has been prepared.

the development should be on developable/previously-developed land or, if it is not on previously developed land, that there are no reasonable alternative sites on developable/ previously-developed land; and

FRA must demonstrate that the development will be safe, without increasing flood risk elsewhere, and, where possible, reducing flood risk overall.

The proposed development proposes to create a high quality built and landscaped environment to benefit all future users of the site, visitors and local community.

The refurbishment and upgrading of the station will benefit the users of the station and visitors to Hampton Court Palace.

The development will include sustainable drainage systems on site, as set out in Chapter 9.

The Council has developed a detailed Development Brief to ensure that the new Development will comply with various requirements and provide long lasting benefits to the local community and area.

Popularity of the exhibition organised for the development (1500 people attended) proved that there is also vital local interest in the development. The development will include cafes, restaurant and public open space to revitalise the local area and draw tourists into the area.

The development is to provide a new transport interchange and `'kiss-and-ride'' car park to encourage use of rail network as being more sustainable then using cars. This should improve the existing inadequate and dangerous transport provision.

The opening of the River Thames front edge to the north of the site though the installation of steps will replace the current 2.3m high retaining wall, providing improved public access to the river. TO BE CONFIRMED IF PROPSED

The Site is classified as a brownfield site. Historical usage of the site includes a coal depot (1963), Public House at the Jolly Boatman site, and sidings where the station car park currently sits. The Hampton Court Station site has a long history of railway use.

Finished .floor levels and ventilation shaft to the basement car parking will be set at a minimum of 9mAOD, which is above the modelled 1 in 100 year flood level including for climate change. Occupiers of the development will therefore be safe.

Dry access from the residential development to areas above the floodplain will be provided at 9.0mAOD. This is 600mm above the 1 in 100-year flood level and takes into account future climate change. All users of the development will therefore have a safe means of access and egress during the 1 in 100 year flood event. This level has been agreed with the EA.

The development will provide floodplain compensation within the site. Level for level floodplain compensation for up to the 1 in 50-year return period flood event level (8.11mAOD) will be provided on the surface.

The top 300mm of flood water up to the 1:100 year (8.41mAOD) will be provided within a geocellular storage system under the public open space. Flood flows progressing west from the Cigarette Island Park will be intercepted at 8.11mAOD and conveyed to attenuation system where the flood water will be stored and then gradually discharged to the River Thames after the peak flow in the river has passed. This has been agreed in principle with the EA.

All reasonable alternatives to the use of tank storage for the top 300mm of the 1:100 - year flood were examined. Given the physical constraints of the existing station and bridge and the Surrey County Council requirement to provide safe pedestrian access around the station, there is no other viable way to provide open compensation on the surface for the remaining 300mm of the 1:100 year peak flood event. It is appreciated that this is not an ideal solution but it has been confirmed that compensation can be provided for all displaced water, providing significant betterment in terms of storage volume in the compensation for higher probability storm events.

The storage tank would be maintained by the management company with specific conditions obliging them to regular checks. The applicant is willing to enter into a S106 agreement to secure the maintenance of this structure. Sumps and access points will be designed to ensure that maintenance access is safe and easy.

As demonstrated in table 1 (Chapter 9), the floodplain compensation will be provided on level for level flood basis and will not only compensate for the exact loss of storage (at the two top 150mm increments) but provide more compensation in excess of the loss of floodplain storage caused by the development. This will not only provide adequate floodplain compensation but reduce flood risk overall.

The development includes a proposal for a two storey basement car park. The access to the car park will be from Hampton Court Way. The top of the access ramp to the car park is set at 8.8mAOD.

Vent outlets within the villas courtyards will be set above the 1 in 100-year peak flood including climate change level (9mAOD).

An escape route will be provided via the fire escape staircase routes located within the buildings, which are connected to dry access routes to areas outside the 1% design flood risk zone.

This attenuation tank will also be used to attenuate the storm water run-off from the site. The Site is currently 93% impermeable; therefore any decrease in surface water run-off will provide benefit over the existing situation and again reduce the overall risk of flooding.

Proposed mitigation measures will not only prevent an increase in flood risk to others but offer betterment provided by increase in total floodplain storage and provision of Sustainable Drainage System at the site. The proposed mitigation will reduce flood risk locally.

The base of the two storey car park structure (0mAOD) will be built below the groundwater table (3m - 4mAOD). A drainage blanket will be constructed around the basement slab to assist in conveying groundwater around the basement structure.

A minimum 8m buffer zone will be provided along the River Thames and the River Mole. The River Mole bank will be kept semi-natural to maintain the established habitat. It is proposed that this area will be fenced off to prevent un-authorised access to the ecological zone.

All the criteria of the exception test have been satisfied, demonstrating that there will be wider sustainability benefits that outweigh the flood risk, the site has been previously developed and the flood risk at the site will be managed adequately providing sufficient mitigation measures to ensure that neither the occupants of the site nor people in its vicinity will be adversely affected.