Service Reservoir Condition Variation Statement

Planning and Projects Department

Received	25 NOV 10 01738
DEPARTMENT OF INFRASTRUCTURE PLANNING and BUILDING CONTROL DIVISION Town and Country Planning Agency
Date and Time
Dacian
Appeal

New Service Reservoir Supply Project (Ramsey) Application for variation to a planning condition

Published November 2011

Contents

1 Existing Situation ..... 3 2 Reason for request of variation to condition ..... 4 3 Assessment ..... 7 4 Conclusion ..... 17

1 - Existing Situation

1.1 Introduction

The Isle of Man Water \& Sewerage Authority (the 'Authority') is submitting a planning application for a condition variation to the existing formal decision notice, 10/00953/B, which has the following condition:

Schedule 4:

1. The Service Reservoir roof is to be finished with top soil and then grassed. All planting shall be carried out in accordance with the approved details in the next available planting and seeding seasons. Any tree or shrub which within a period of 5 years from the completion of the landscaping works, is removed, or becomes seriously damaged or diseased shall be replaced in the next planting season with another similar size and species, unless the Planning Authority gives written consent to any variation.

After consultation with the Building and Control Division it is given to be understood that seeking this condition variation will in no way impact upon the full approval already granted for 'construction of a service reservoir and temporary track and access'.

Furthermore this condition variation is submitted after consultation with the area planning officer at the site of the development.

The Authority are seeking a revision to the first sentence to read Schedule 4:

1. The Service Reservoir roof is to be finished with river-washed gravel in accordance with the Authority's Service Reservoir Specification.

2 – Reason for request of variation to order

2.1 Preferred finish

The preferred roof finish is that contained within the Authority's Service Reservoir Specification, as follows:

1.2 Reservoir Roof 1

The reservoir roof shall have a waterproof membrane (CIRIA recommendation for reinforced concrete roof slabs - C5.7); either a bonded membrane with geotextile fabric protection above or unbonded with geotextile fabric protection above and below. However, such a membrane shall not be a substitute for a properly designed, constructed, and tested waterproof roof.

The roof shall be covered only with a 250 mm depth of 40 mm river washed gravel, unless planning requirements state otherwise. Plate 1: Archive photograph of the roof finish at Glenneedle Service Reservoir The photograph was taken with the man-entry lids open. Normally these would be closed

Plate 2: archive photograph of the roof finish at Ballakerka Service Reservoir

2.2 Cost implication

The cost implication of the grass finish is in the region £80,000. The reason for this is that:

• the reservoir roof must be increased in thickness from 200 to 300mm and have additional reinforcing material to take the additional load
• the reservoir must still have gravel and additionally a drainage layer below the level of the grass finish

Figure 4: preferred solution

2.2 Maintenance implication

A grass roof will require some additional maintenance in that the grass roof will require trimming during the summer months this will have direct time and cost implication on the Authority.

3 - Assessment

3.1 Topography

The site and location within site of the development is such that the topography of the land completely conceals it from view from below and it is highly unlikely it can been seen from above.

The map below indicates:

1. The red band shows the contour line on which the service reservoir sits. The blue dot represents the location of the service reservoir.
2. The olive banding is land above the contour line from which it may in theory be possible to view the site were it not for the localised topography which conceals the site from view. The only potential public view point being a limited section between Guthrie's Memorial and the Mountain Box.

3.2 Visual Impact

Using the contour map it is possible to plot the line of site of relevance from both Guthrie's Memorial and the Mountain Box. The photographs below qualify what can be seen and for the avoidance of doubt there are also aerial photographs taken from the WINGs GIS system.

View from Guthrie's Memorial

View from Guthrie's Memorial (Localised zoom)

The plan below shows the fields which can be seen in the above photograph. The service reservoir site is completely hidden from view by a combination of existing hedging and topography. The film studio (Baldromma Farm) and the school rugby pitch have been used as points of reference.

Ramsey Golf Course

The area shaded in green represents the end of the line of sight from Guthrie's Memorial

View from the Mountain Box View from the Mountain Box (Localised zoom)

The plan below shows the fields which can be seen in the above photograph. The service reservoir site is completely hidden from view by a combination of existing hedging and topography. The film studio (Baldromma Farm), Glen Link and toe of Sky Hill have been used as points of reference.

The area shaded in orange represents the end of the line of sight from the Mountain Box

View from below

The roof of the service reservoir is level and horizontal therefore it cannot be seen from below, either close-up, or at distance and in any case, the site is largely hidden from view.

However, to further conceal the site, as part of the restoration of site the Authority will regrade the front elevation of site, in the form of low earth banking, seed and locally plant with gorse or similar.

The photograph below shows the actual height (approximately 1.5 m ) of the top of the service reservoir whilst the following photograph indicates what that will look like when complete.

3.3 The site of the proposed development

The site has been accurately surveyed. The blue posts in the photograph represent the profile and actual finish height above ground profile the valve chamber, the area of the service reservoir at greatest elevation above normal ground profile.

The photograph below is indicative of how the site will look when complete. The gravel roof will not be visible from any point other than above.

16

4 - Conclusion

The service reservoir could be constructed within the existing approval however the additional cost and maintenance requirements should be carefully considered. When making the consideration.

Furthermore detailed investigation suggests that it is highly unlikely that any person could see or be affected by the alternative roof covering.