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Sea Link


Sea Link



Information for landowners

Before we can submit our application for development consent, we need to understand who has a legal interest in the land in and around the areas being considered as part of the proposals for Sea Link.

Under the Planning Act 2008, we are required identify persons with an interest in land for the purposes of consultation and notification, this process is known as ‘diligent inquiry’. We have appointed the land referencing firm, TerraQuest, to assist with diligent inquiry by identifying those land interests and contacting individuals to confirm their interest in the land.

We have also appointed the land agency firm, Dalcour Maclaren, to assist in liaising with landowners and occupiers to arrange access for surveys to be carried out along the route.

You are entitled to appoint a suitably qualified representative to act on your behalf where we are seeking rights to carry out works on your property. An agent/surveyor will advise you on the process, your rights and will handle any compensation claims on your behalf. We will reimburse you for professional fees reasonably incurred in respect of all claims and advice on legal agreements in connection with associated land rights. More information on this can be found within our Guidance on Land Rights and Payment of Surveyors’ Fees documents. 

If you believe your land or property may be affected but have not been contacted by us, please email [email protected] in the first instance.

Best practice guides

To help explain how Sea Link would be built, we have produced 'Best Practice' guides which show how National Grid constructs overhead lines and underground cables. You can view these guides by following the links below.

Whilst National Grid will adopt the best practice as set out in these documents wherever it is possible and reasonably practical, there will be some instances where we cannot do this. You can find information about the specifics of constructing Sea Link in the Preliminary Environmental Information Report, which is available in our Document library.

Construction best practice for overhead line installation

Construction best practice for underground cable installation


All key stakeholders, such as the local planning authorities and environmental bodies (such as Natural England) have been fully informed of our planned works.

To understand more about the local environment, and to inform the environmental impact assessment, we need to carry out surveys. Surveys may take place on land within our draft order limits (the land that would be required to build and operate Sea Link, on some adjoining land, and in areas that have been identified through consultation feedback as potentially sensitive.

Ongoing surveys

Below is a list of our ongoing and upcoming surveys. If for any reason a survey cannot take place on the scheduled date, such as poor weather conditions, we will endeavour to reschedule the survey in a timely manner.

Access to land plots is agreed before any surveys may take place.

July 2024 onwardsArchaeology surveysProject route in Kent and SuffolkFollowing on from geophysical surveys, we are now undertaking archaeological assessments. Further information on the nature of these surveys can be found in our fact sheet in the document library.
March - June 2024Breeding bird surveys

Kent - Cliffsend, Ebbsfleet, Minster, and Richborough.

Suffolk - PRoWs between Aldeburgh and Suffolk.

To assessing breeding bird activity and distribution across the survey area
April - June 2024Reptile surveys

Kent - Cliffsend, Ebbsfleet, Minster, and Richborough.

Suffolk - Aldeburgh & Sternfield.

To determine the presence of reptiles in suitable habitat such as rough grassland, verges, scrub and dunes.
May - June 2024Bat activity surveys.

Kent - Cliffsend, Ebbsfleet, Minster, and Richborough.

Suffolk - Aldeburgh, Aldringham, Knodishall, Friston, and Saxmundham.

Two surveyors walk a straight line, which include 'spot counts' at pre-determined points which are potentially important for foraging or commuting bats.
May - June 2024Terrestrial invertebrate survey

Kent - Cliffsend, Ebbsfleet, Minster, and Richborough.

Suffolk - Aldeburgh

Recording of terrestrial invertebrate species uses various methods, such as sweep netting, sieving dead wood/leaf litter and pitfall traps as per published guidelines, to sample as wide a range of invertebrates as possible. Identification, where possible, should take place in the field, however, if this is not possible, using microscopes within a lab
May - June 2024Bat detector surveys

Kent - Cliffsend, Ebbsfleet, Minster, and Richborough.

Suffolk - Aldeburgh, Aldringham, Knodishall, Friston, Saxmundham, and Sternfield.

Using up to 3 detectors for each transect, left for five to seven nights, bat movements are recorded. Recorded frequencies help to identify species and whether bats are feeding.
May - June 2024Otter, water vole, and beaver surveysKent - Ebbsfleet, Minster, and Richborough.

Surveys undertaken on aquatic habitats that lie on or adjacent to the order limits of the project. Otter surveys will include waterbodies within a 200m buffer zone.

Surveys involved a detailed search for field signs of species present such as spraints, footprints, or holts.

Previously undertaken surveys

May 2024Aquatic macroinvertebrate survey

Kent - Cliffsend, Ebbsfleet, Minster, and Richborough.

Suffolk - Knodishall, Friston, and Saxmundham.

Conducted on either the river bank, or in the river channel. If safe, three minutes is spent disturbing river bed with the foot while collecting invertebrates in a net. A similar sweep is conducted from bankside through vegetation.
May 2024Habitat conditions assessment

Kent - Richborough.

Suffolk - Aldeburgh, Knodishall, Friston, Saxmundham, and Sternfield.

To inform baseline conditions required for the environmental statement. The assessment will establish if protected species surveys are required.
February - May 2024Dormouse surveysSuffolk - Aldeburgh, Knodishall, Friston, and Saxmundham.Checking dormouse tubes, set up within hedgerows for any evidence of activity. 
April 2024Important hedgerows

Kent - Ebbsfleet and Minster, 

Suffolk - Aldeburgh, Knodishall, Friston, Saxmundham, and Sternfield.

To establish the state of hedgerows, regarding length and condition, as well as character of species present. The assessment also identifies which hedgerows are of particular importance for wildlife and landscape.
January - April 2024Bird corpse searchKent - Minster and Richborough.To test scavenger removal from the sites to have a clearer idea of the number of dead birds found by surveyors against the number taken by predators.
February - April 2024Winter landscape and heritage photographySuffolk - PRoWsSurveyors take photographs from pre-determined viewpoints.
January - March 2024Nighttime bird surveysKent - Cliffsend, Ebbsfleet, Minster, and Richborough.To assess bird flight activity and distribution over the survey area at night.
January - March 2024Coastal bird surveysSuffolk - Aldeburgh.To assess bird flight activity and distribution over the survey area.
September 2023 - January 2024MarineTarget areas along the proposed marine route.This survey is undertaken to identify the physical features of the seabed. Please see the Notice to Mariners for further information on the locations -

January 2024 – February 2024

Traffic surveys

Suffolk – Aldeburgh, Snape, Leiston and Saxmundham.

To collect traffic, traffic volume and speed data to support transport planning and design.

November - December 2023, February 2024Bat roost surveysSuffolk - Aldebrigh, Friston, Knodishall and Sternfield.To identify and collect physical evidence of bat activity. If no evidence is found, then the ecologist will make an assessment based on any roosting features that present high potential.
November 2023 - January 2024Tree surveysKent - Ebbsfleet and Minster.
Suffolk - Aldeburgh, Knodishall, Friston, Meadowcroft, Sternfield, and Saxmundham.
Surveyors will undertake a non-intrusive walkover tree survey recording the location and dimensional data of all trees within and adjacent to the study area. The survey will record the tree species, dimensions, condition and quality.
November 2023 - January 2024Vantage point bird surveysKent - Ebbsfleet, Minster, and Richborough.
Suffolk - Aldeburgh and PRoWs.
To assess bird flight activity and distribution over the survey area.
November - December 2023Aquatic ecologyKent - Ebbsfleet and Minster.
Suffolk - Aldeburgh, Friston and Sternfield.
During aquatic ecology surveys, the surveyor will enter the watercourse and kick sample for three minutes using a pond net followed by an additional one-minute active search. Should the watercourse be deemed unsafe to enter, the surveyor will conduct a sweep sample from the bank for three minutes.
October - December 2023Dormouse surveys

Kent - Cliffsend and Minster.

Suffolk - Aldeburgh, Knodishall, Friston, Sternfield and Saxmundham.

Dormouse tubes are set up within hedgerows and left for a period of time to record any evidence of dormouse activity. 
October 2023Bat activity surveysKent - Cliffsend and Ebbsfleet.
Suffolk - Aldeburgh.
Night work - surveyors record the activity of bats. Sunset until 2 hours post sunset. 
September - December 2023Geophysical surveysAcross the proposed route corridor in both Suffolk and Kent.Surveyors use non-intrusive methods to assess any potential features beneath the subsoil, such as buried archaeological remains.
September - October 2023Bat monitoring surveysKent - Cliffsend.Surveyors walk transects around the site and record bat activity. SM4 bat detectors are installed at specific fixed locations within a site and record all bat activity over a series of nights. 
September - October 2023Ground investigations (boreholes and trial pits)Across the proposed route corridor in both Suffolk and Kent.The purpose of the work is to gather data on ground conditions within the project area, informing the design options of different elements of the project.

Boreholes will either be investigative (sample gathering only) or monitoring (left in situ temporarily).

Cone Penetration Tests push instrumented cones on rods into the ground at a continuous rate to a depth of approx. 10 m below ground level.

Trial pits will be excavated by an excavator, taking relevant samples and at selected locations monitoring rates of groundwater infiltration. All trial pits will be subject to archaeological monitoring.

All works are to be undertaken initially via Permitted Development Rights and in agreement with the Land owners, by an experienced and competent ground investigation contractor and, following completion of the works, land will be restored in accordance with Environment Agency good practice guidance.
September 2023Intertidal environmental surveySuffolk - Aldeburgh.The purpose of this survey is to record the characteristics of what is found on the bottom of the intertidal seabed between the Mean High Water Springs (MHWS) and Mean Low Water (MLW) strandlines.
August - September 2023 Engineering landfall surveysKent - Pegwell Bay and West of St Augustine’s and Stoneless golf courses.
Suffolk - Aldeburgh.
This survey is undertaken to understand the physical features of the area and their structure.  Various survey techniques are used to achieve this including the use of a drone that gathers data about the natural and man-made features of the land, as well as its terrain.
August - September 2023Hobby surveysSuffolk - PRoW.Consists of four visits, typically between April to September. The initial visit is to check for any occupancy of Hobbies. The second visit is to check for any active Hobby nests. The third visit is to again check for any more active nests but also for any young. The final check is to check for any fledged young. 
June - July 2023Engineering landfall surveysKent - Pegwell Bay.See above.
June 2023Noise monitoringKent - Ebbsfleet.
Suffolk - Saxmundham and Sternfield.
Two surveyors will employ sound monitors, taking account of constraints within the survey area (e.g. reflective surfaces, security, access, local noise sources). The monitors will be left in place for seven days.

Discussion with land owners may be required. 
June 2023Nightjar surveysSuffolk - PRoW.Transects follow the length of all hedgerows, fence-lines and field margins, with deviations where possible. Surveys are conducted at dusk as nightjars are most active, surveyors will walk the route listening for nightjar sounds.
June 2023Intertidal environmental surveyKent - Pegwell Bay.See above.
April and June 2023Ecology phase 1 walkoverKent - Cliffsend, Ebbsfleet, Minster, and Pegwell Bay.
Suffolk - Aldeburgh.
Undertaken by two surveyors, the survey areas the vegetation, and any species are mapped onto Ordnance Survey maps. A desk study using aerial photography was used prior to the walkover.
March - July 2023Common bird censusKent - Ebbsfleet, Cliffsend Cottington Hill, Lower Gladstone and Minster Marshes. 
Suffolk - Aldeburgh, Saxmundham, Thorpeness, and PRoW.
The survey follows hedgerows, fence-lines and field margins to record any species that may be passing through the survey area. Survey routes are mapped, and the direction walked alternated on each visit, to ensure that all areas are covered at various times of day.

Surveys are undertaken early in the morning, during this time, breeding birds are more active and can be detected in song more frequently. These surveys are conducted between March and July.
February - June 2023Vantage point surveysKent - PRoW.The purpose of vantage point surveys is to record flight lines of species which are potentially sensitive to collision with infrastructure to assess collision risk. Birds on the ground within the survey area will also be recorded.
January - March & May 2023Landscape viewpoint surveysKent - Minster Marshes and PRoW.
Suffolk - Aldeburgh, Friston, Knoddishall, Leiston, Saxmundham, and PRoW.
Landscape viewpoint surveys are required to support the landscape (mitigation) design and the design of the layout of the proposed converter station and substation infrastructure. 

The site surveyors will visit locations surrounding the converter station and substation sites, cable routes and landfall, to review potential locations for publicly accessible photography.

Kent only - The surveys will also allow us to review the overhead line connection over the River Stour and inform the design of the proposed overhead line towers.
October 2022 – March 2023Wintering bird surveysKent – Cliffsend, Ebbsfleet, and PRoW.During a wintering bird survey, undertaken between October and March inclusive, two surveyors will look for any wintering birds; all calls and behaviour will be recorded. These will include foreshore and field counts.
September 2022Hobby surveysRSPB Area.See above.
July - August 2022Arboricultural walkoversKent – Ebbsfleet.
Suffolk Aldeburgh, Aldringham, Hazelwood, and Sizewell.
Usually undertaken by two surveyors. These surveys are non-intrusive and consist of noting scientific name, measurements, age, branch spread, physiological and structural conditions, management conditions and whether there is a Tree Preservation Order or a Conservation Area Protection.
June 2022Breeding bird surveySuffolk – PRoW.See above.
April – May and December 2022Ecology phase 1 walkoverSuffolk - Aldeburgh, Aldringham, Hazelwood, Knoddishall, Leiston, and Sizewell.See above.

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