Installation of the replacement pipeline will likely take place in December 2022 and January 2023.

Construction updates will be provided to the local community at least two months before the installation works commence. We will agree how we communicate this information with local authorities.

The map above provides information on installation within the SANG. As outlined in the planning process, the project will be narrow working through the SANG. Further information on our construction plans can be found below.

About installation

Where required, vegetation and tree clearance will be undertaken by a small team. This will take place in early autumn 2022 before installation commences.

Before installation starts, the first thing you will see is signs notifying SANG users that works will be taking place.

When installation starts, Heras-type fencing bolted together, or strong-wall fencing, will be used to secure the working area.

You may also see mobile welfare units, equipment, materials and vehicles within the working area.

During the open cut installation process, you may see deliveries of the steel pipes. These will be brought to site in a ‘just-in-time’ delivery sequencing – this is because we want to reduce the space needed for the compound within the SANG. We will also have 24-hour security of the working areas within the SANG.

Access to the SANG will be available throughout installation.

The undesignated paths/tracks within the SANG will be crossed by the working area. At the intersection between the working area and footpath/tracks, pedestrian crossing points will be installed. Pedestrians will have priority at these crossing points.

Additional signage for diversions onto alternative existing paths will be displayed at the SANG access points and will include routes into Frith Hill woodland. These will be put in place as appropriate in advance of any closures, and will be kept up to date, with clear user-friendly information. In addition, when works are ongoing, key staff will be identified as the points of contact for day-to-day queries.

The circular walk will be impacted by construction. However, this will be adjusted to allow people to utilise a shortened circular route during the works.

Dog walking and dogs being allowed off the lead will be possible during the works.

Parking at the SANG will be maintained throughout installation works.

The local landscape character of St Catherines SANG comprises a number of formal paths within amenity grassland and trees. Younger trees are scattered within the Order Limits with larger more mature trees around the boundary of the SANG, some of which are located within the SANG and some within the adjacent land. It is anticipated that none of the mature trees will require removal.

It is anticipated that the open cut may require the removal of some of the younger trees and shrubs and branch pruning of nearby trees.

It is anticipated that the construction compound will require the removal of a small number of younger trees and shrubs which have recently been planted within the SANG but not the mature trees on the boundary with St Catherines Road, although branch pruning may be required.

We have committed to a narrow working area, a maximum width of 15m, to install the replacement pipeline through the SANG.

We will be using tried and tested techniques to work around tree roots through the park, including hand digging and use of air spades.

In addition, the project’s Environmental Clerk of Works and arboriculturalist will visit working areas to provide specialist advice when any works to trees, such as branch removal, are required.

In the construction compound area, the roots from the mature trees along St Catherines Road will be protected from our installation works.

We will be using an open cut technique to install through the SANG.

Open cut installation will take place along approximately 160m of the eastern boundary of the SANG.

The construction of the pipeline through St Catherines SANG will likely commence from the north-eastern corner, heading in a southerly direction within a narrow working width towards the construction compound.

We have committed to reducing the working width to a maximum of 15m wide, which covers the total length of the open cut work within the SANG.

A 15m wide fencing/barrier system will be erected within the Order Limits – this is to segregate the ‘live’ working area from publicly accessible areas. As the works progress, the fenced area will be relocated/extended so that no more than 50m of continuous fencing is in place before a public crossing point.

Acoustic material will be applied to the fencing to limit the impact of noise pollution on the tranquillity of the SANG.

Fencing material will be selected to reduce the visual impact on the SANG, maintaining low visibility of the working area.

Size of plant (vehicles and machinery) will be smaller than traditional open cut plant. This is necessary to work safely within the reduced 15m working width.

Construction access for the majority of the works within the SANG will be from St Catherines Road.

The work areas will be fully secure with locked gates and 24-hour security.


Where the topsoil has been stripped and stored, this will then be replaced after the works have been completed and either reseeded or left to naturally regenerate, following discussion with Surrey Heath Borough Council.

The vegetation reinstatement will be subject to a five-year aftercare period.

Undesignated Paths

The circular walk around the SANG will be reinstated to its previous condition throughout.

Footpaths crossed by the working area will be reinstated once the open cut works are complete. Like-for-like footpath surfacing will be used for reinstatement, unless otherwise agreed with Surrey Heath Borough Council.

All construction activities within the SANG will be fully demobilised within the two-year period and reinstatement completed with all protective fencing removed unless otherwise agreed with Surrey Heath Borough Council.