Our ref: SL/2007/102360/01-L01
Your ref: 2007/2970
Date: 24th January 2008
Ann Biggs
Elmbridge Borough Council
Planning Policy
Civic Centre High Street
Esher
Surrey
KT10 9SD
Dear Ms Biggs,
Proposal: DEMOLITION AND COMPREHENSIVE REDEVELOPMENT OF HAMPTON COURT STATION, THE JOLLY BOATMAN SITE AND ADJOINING LAND TO INCLUDE 66 RESIDENTIAL UNITS, RETAIL AND COMMERCIAL FLOORSPACE (592 SQM), 46 BEDROOM HOTEL, 61 BEDROOM CARE HOME, REFURBISHED RAILWAY STATION, NEW TRANSPORT INTERCHANGE, NEW AREAS OF PUBLIC OPEN SPACE, CAR PARKING, HIGHWAYS IMPROVEMENTS AND WORKS TO THE THAMES RIVERBANK TOGETHER WITH OTHER WORKS INCIDENTAL TO THE PROPOSED DEVELOPMENT
Information
Reference: ENVIRONMENTAL STATEMENT - GLADEDALE GROUP LIMITED, NETWORK RAIL AND THE ROYAL STAR & GARTER HOMES, DATED OCTOBER 2007
Location: HAMPTON COURT STATION & THE JOLLY BOATMAN, HAMPTON COURT WAY, EAST MOLESEY, SURREY KT8 9AE
Thank you for consulting the Environment Agency on this planning application which we received on the 22nd November 2007. We have the following comments:
The site has the following environmental constraints and opportunities:
· Flood Zones 3 and 2
· The Thames, Ember and Mole (main) rivers are located within the vicinity of the site.
· The site is located on a High-Risk zone for Groundwater vulnerability and our records show that the site is potentially contaminated
Therefore the key issues and areas of interest for the Environment Agency at this site are:
· Flood risk and surface water drainage;
· Water Related Recreation, Public Amenity, Navigation & Waterways Operation
· Landscape Architecture
· Impact on ecology and the mitigation/compensation measures
· Prevention of pollution to Groundwater & potential contaminated land remediation
· Pollution prevention and control measures
The Environment Agency has no objections to the proposed development subject to the imposition of the following conditions on any planning permission granted.
As part of our new approach to major planning projects, we have been involved in pre-application discussion with the applicant regarding all of the following issues:
Flood risk and surface water drainage
The site lies within Flood Zone 3 as defined by Planning Policy Statement 25, Development and Flood Risk (PPS25). Flood Zone 3 refers to land where the indicative annual probability of flooding from non-tidal river sources is 1 in 100-years or less (i.e. it has a 1% or greater chance of flooding in any given year).
The modelled flood level on site from theLower Thames Flood Risk mapping for the 100 year flood event is 8.41mAOD and the 100 year plus 20% (added for climate change) level is 8.96mAOD.
Floodplain Compensation
The proposed development will displace flood water.To be acceptable to the Environment Agency the applicant was required to provide level for level floodplain compensation. This is requested to ensure that there is no worsening of flood risk elsewhere.
Ground reprofiling of the Jolly Boatman site has been proposed for floodplain compensation up to the 1 in 50 year flood return period of the River Thames. Floodplain compensation for flood water displaced by the proposed development above the 1 in 50 year return period will be compensated for using geocellular storage because of the spatial restrictions on site. Flood storage in addition to the minimum storage requirements will be provided for in lower flood return periods, as proposed within the Flood Risk Assessment (FRA).
Safe access
The FRA states that dry pedestrian access is available for the proposed development up to 9.0mAOD.We request the following condition in order to ensure a safe access route is agreed and installed:
CONDITION: Development shall not commence until details of a safe exit route, not adversely affecting the flood regime, to land outside the 1 in 100 plus 20% (added for climate change) year flood plain, are submitted to and agreed in writing by the local planning authority. This route must be in place before any occupancy of the building(s).
REASON: To provide safe access and egress during flood events and reduce reliance on emergency services.
Finished Floor Levels
We request the following condition in order to ensure floor levels are set as proposed in the FRA:
CONDITION: Finished floor levels for the proposed development shall be set no lower than 300mm above the 1 in 100 year plus 20% (added for climate change) flood level of 8.96mAOD, OR, where this is not practical, flood proofing measures shall be incorporated up to the 1 in 100 year plus 20% (added for climate change) flood level, at 9.26mAOD.
REASON: To protect the property from flooding.
Underground basement car park
As an underground basement car park has been proposed, we request the following condition in order to ensure increased protection from any flood waters:
CONDITION: The entrance to all basements shall be set above 9.0mAOD, to allow for wave action, on all sides.
REASON: To reduce the risk of flooding and inundation in the basements.
Surface Water Drainage
We commend the inclusion of sustainable drainage methods such as the 930m2 of Green roofs and 480m2 of gravels with plantingthat have been proposed.However, the FRA states that the site is 1.76ha and that the redevelopment proposes an increase in impermeable areas on site by an additional 8%.PPS25 requires that a separate drainage strategy is required. We therefore request the following condition:
CONDITION: No development approved by this permission shall be commenced until a scheme for the provision of surface water drainage works has been submitted to and approved in writing by the Local Planning Authority. The drainage works shall be completed in accordance with the details and timetable agreed.
REASON: To prevent the increased risk of flooding by ensuring the provision of a satisfactory means of surface water disposal.
SI06 Agreement Recommendation
We strongly recommend that an agreement is drawn up within any S106 agreement for regular maintenance of the cellular storage used for surface water attenuation and floodplain compensation.If the storage became blocked through lack of maintenance, flood risk both on the site and elsewhere could be increased.
Please note that we are reliant on the accuracy and completeness of the reports in undertaking our review, and can take no responsibility for incorrect data or interpretation made by the authors.
Water related recreation, public amenity, navigation & waterways operation
The main interest for the Waterways department at the proposed development site is the improvement and future use and access to the Passenger Vessel Landing Wharf downstream of Hampton Court Bridge and the public realm connecting to that facility.
At pre application meetings with the designers/consultants working for the applicant this has been the primary focus of our attention. However during those meetings our Recreation officer did request that the applicant should consider how the proposal as a whole will relate to the public route to Hampton Court Bridge and Hampton Court Palace with a particular emphasis on the views from and to the River Thames and from and to Hampton Court Palace. Please note the comments related to this aspect under the ‘Landscape Architecture’ section of this response.
The design presented for the Wharf with the terraces and steps includes improved wharf edge levels that better meet river water levels for improved access and use of the wharf by passenger vessels. These designs havethe least effect, compared with other previously proposed options such as floating pontoons,on the gravel river bed so it will be more protective of fish populations.We note that the wharf is often used in connection with events at Hampton Court Palace for water transport links so we consider that this design will better serve that interest and therefore the experience for tourists visiting the site.
Also the design of public terraces meeting the steps and wheel chair ramp will improve the public amenity of this important public space and wharf. We consider that this new design will better ‘self manage’ connectivity to the River Thames and give the location a new status.
The proposed public realm between the proposed hotel and the edge of the wharf terraces includes a design feature in relation to proposed mitigation that provides for underground flood storage and the surface removes the present mixed levels formed by theexisting side road. We accept the form of this public open space for the manner in which it meets the riverside terraces and steps as it will improve access but we consider that there is scope for additional landscaping in this area.
Landscape Architecture
The Environment Agency has a duty to further the conservation and enhancement of natural beauty when fulfilling it's water management functions including it's role as a Statutory Consultee. After reviewing the submitted information related to the ‘Public Realm and Landscape Strategy’ and the ‘Townscape, Heritage & Visual Assessment’, we have the following comments:
The proposed development appears likely to have a detrimental impact on the visual amenity and landscape character of the area, due to the scale, bulk and density of the development, the proximity to the river and the poor quality of the building plans and design which consists of uniform blocks which present a somewhat regimented and poorly considered elevation to the river.
The Environment Agency is very concerned about the adverse effect this scheme would have on the landscape character and important river views in this iconic, sensitive riverside location on the River Thames opposite Hampton Court, and on the surrounding open green space on and beside Cigarette Island.
In addition, the Environment Agency is a partner of the Thames Landscape Strategy Hampton to Kew and is supportive of the views expressed by the Strategy in it's letter dated 15th January 2008 and of the policies contained in the Strategy that are relevant to this area. The Environment Agency is also sympathetic to and supportive of the concerns that Historic Royal Palaces have in regard to the impact this scheme would have on the character of the area and the environs of Hampton Court and Hampton Court Bridge.
Impact on ecology and the mitigation/compensation measures
Following review of the submitted information, we request the following conditions in order to ensure that suitable ecological mitigation and compensation measures are incorporated into the development. We ask that we be consulted on any details submitted in compliance with these conditions:
Lighting
The corridor adjacent to a watercourse provides important habitat foraging bats which feed on invertebrates and utilise tree and hedgerow lines as commuting routes which are disrupted by artificial lighting, particularly at dawn and dusk. Please contact the Environment Agency for further information on river corridors for the benefit of wildlife.
River channels and waterbodies with their wider corridors should be considered Intrinsically Dark Areas and treated as recommended under the Institute of Lighting Engineers “Guidance Notes for the Reduction of Light Pollution”.
CONDITION: There shall be no light spill into adjacent natural terrestrial and aquatic habitats. To achieve this, and to comply with sustainability, artificial lighting should be directional and focused with cowlings to light sources in close proximity to the wetland habitat.
REASON: Artificial lighting disrupts the natural diurnal rhythms of a range of wildlife using/inhabiting the river and its corridor habitat.
Passenger Vessel Landing Wharf
We support the incorporation of the new landing stage as stated elsewhere in this response, but we consider that further mitigation measures can be incorporated in order to enhance the area for fish. We therefore request the following condition to ensure that final designs and levels are agreed before construction:
CONDITION: No development approved by this permission shall be commenced until a final design for the terraces, wheelchair access ramp, steps and wharf (landing stage) riverside edge levels have been approved by and implemented to the satisfaction of the Local Planning Authority. This shall include the enhancement of the river wall for fish.
REASON: To protect and conserve the adjacent river Thames ‘Site of Metropolitan Importance’ and to reduce impacts on the aquatic habitat and species. Also to mitigate for loss of overhanging refuge and increased disturbance in this area.
Green Roofs
We support the inclusion of green roofs but require full detail of the structures through the following condition:
CONDITION: The design and location of the living roofs shall be submitted to and approved in writing by the Local Planning Authority before the construction of any of the buildings commences. This must include location, design, dimensions and materials.
REASON: To ensure best practice measures are included in the design of these features and mitigation for loss of habitat.
Landscaping and treatment of the river buffer zones
CONDITION: A landscape management plan, including long term design objectives, a planting scheme, management responsibilities and maintenance schedules for all landscape areas, other than small, privately owned, domestic gardens shall be submitted to and approved in writing by the Local Planning Authority before the development commences. The landscape management plan shall be carried out as approved.
REASON: To protect/conserve the natural features and character of the area.
CONDITION: A Buffer Zone 8 metres wide alongside the River Ember shall be established in accordance with details which shall be submitted to and approved in writing by the Local Planning Authority before the development commences.
REASON: To maintain and protect the character of the watercourse and to provide undisturbed refuges for wildlife using the river corridor.
CONDITION: No development approved by this permission shall be commenced until a planting scheme for the site, has been approved in writing by the Local Planning Authority. The approved scheme shall be carried out in accordance with a programme for planting and maintenance related to stages of completion of the development.
REASON: To protect, restore or replace the natural features of importance within or adjoining the watercourse.
CONDITION: No development approved by this permission shall be commenced until an Ecological mitigation, compensation and enhancement scheme and an Environment Management Plan, has been submitted and approved by the Local Planning Authority. Development shall be carried out in accordance with the approved details. This scheme shall outline the detailed design of all ecological mitigation, compensation and enhancement measures listed within the Environment Statement dated October 2007 including native tree and shrub planting; creation of 930m2 living roof; provision of bat boxes and bird boxes. This shall include a scheme for the protection and enhancement of the buffer zone to the River Ember.