Corridor of Interest

With the information from the desk study and the Site reconnaissance major constraints (cities, estuaries, mountains, major environmental sites) are identified and decisions formulated on the merits of deviation or crossing. Broad cost estimates are usually undertaken to support such decisions. For a route length of 100-200km, a corridor of interest is defined this would normally be a width of 5km for this length of pipeline.

The corridor is then transferred to 1:50,000 scale topographic maps and all visible routing constraints identified. Site reconnaissance from public rights of way would be undertaken to support this process. Constraints include:

• development 'pinch points'

• optimum locations for major crossings

• unsuitable ground conditions

• woodland

• visible environmental sites, e.g. nature reserves

Based on likely pipeline diameter and operating pressure, Minimum Distances to occupied buildings are calculated from the Codes of Practice. From the viewpoint of public safety, the ideal alignment will:

• avoid all occupied dwellings by at least 1 x BPD

• avoid all category S(ii) buildings (hospitals, old people's homes) by at least 3 x BPD

• minimising the total number of occupied buildings within 5 x BPD of the pipeline.

Leading the small team, the routing engineer should conclude this phase of the work by identifying the optimum route option within a reduced route corridor (say 1-2km wide for 100-200km route, typical).

© Andrew Palmer & Associates, part of the Penspen Group 18 4.5 Initial Consultation

Constraints identified from topographic and geological maps, codes and standards and from site reconnaissance represent only part of the data required to finalise the pipeline route. At the earliest possible opportunity following development of the broad corridor of interest, key Statutory Authorities must be consulted to:

• recover data on non-visible constraints

• provide early notification of project proposals

A limited list of Authorities who control sites of major dimensions should be initially consulted. Discussions are usually held in confidence as landowners and occupiers will not be aware of the proposals at this stage. Examples of key participants likely to impact route selection are:

• Planning Authorities (structure plans, SSSI's mineral sites)

• Water Authorities (abstraction sources particularly relevant to oil pipelines)

• Special cases depending on route location (harbour boards, MOD etc.) 4.6 Consultees

The list of consultees will be extended as the pipeline design progresses. In view of the requirements for confidentiality, this initial list should be minimised. Public utility authorities are unlikely to affect route selection at this scale for example and would be contacted during a later phase. The extended list that will normally have to be contacted is given below. This list is not complete and is only indicative of who may be contacted. Usually the Regional, County, District Council or Unitary Authority will advise on who is who.

The key of who should be contacted is be sensible and only talk to people how can provide information that is needed for the design and have a prepared line for everybody about what is planned.

Governmental

Department of Trade and Industry (DTI)

Ministry of Agriculture, Fisheries and Food (MAFF) Health & Safety Executive (HSE)

English Heritage Councils

Regional / County Council Archaeology, Planning etc. Structure plan for area.

District Council / Unitary Authorities / Borough Council Mining

British Coal / RSVP Mining Other Mining / Quarry Interests

© Andrew Palmer & Associates, part of the Penspen Group 19 Power/communications

Powergen / National Power / National Grid British Telecom

Water

Water Companies (ie. Thames Water) British Waterways (Canals, Rivers, etc) Environment / Nature

Department of Environment / Environmental Agency English Nature

Joint Nature Conservation Committee (JNCC) Royal Society for the Protection of Birds (RSPB) Country Wildlife Trust / British Trust for Ornithology Wildfowl and Wetland Trust

County Plant, Invertebrate, Birds, Badgers & Bat Recorders Countryside agencies

Countryside Commission / National Farmers’ Union National Trust / Country Landowners Association Forestry Commission / Regional Tourist Board Pipeline/Rail

Department of Transport / British Rail, Rail Track, Properties Board (et al) British Gas (Transmission and Distribution)

Oil Pipeline Agency Specialist agencies

Broads Authority.

Property Services Agency Internal Drainage Boards Civil Aviation Authority 4.7 Large scale routing

Sufficient information to identify the preferred route for plotting on 1:10,000 scale maps is now likely to be available. A corridor of interest, say 500 metres either side of this line will however be retained for environmental study and detailed consultation with all affected Authorities and third parties, except landowners/occupiers. Retaining this narrow corridor of interest avoids data recollection in the event of minor re-routes during detailed route design.

© Andrew Palmer & Associates, part of the Penspen Group 20 As access to private land remains unavailable for the majority of the route, an aerial photography and video survey is frequently undertaken at this stage, particularly where recent developments have superseded map data. Some of the new software packages can generate 3D model of the route form aerial data. This data can then be used in Geographical Information Systems (GIS) which bring a whole life concept to the design.

It is important to have identified a single route centre-line prior to approaching landowners with 1:10,000 scale maps. As previously noted, alignment should only thereafter be modified following identification of further constraints, which were unknown prior to referencing e.g. land drainage systems.

The pipeline promoter nominates limits of route deviation at the time of submission of a Construction Authorisation Application to the Department of Energy. Unless substantial uncertainty remains on route acceptability from a Statutory Authority minimum deviation limits typically around 200 metres are usually nominated to eliminate the opportunity for landowners to demand unrealistic deviations.