Civils & Groundworks
Trenching, ducting, chambers, bases, bollards, drainage, lighting and reinstatement - modest civils carried out in phases on a live trafficked site, where keeping customers moving matters as much as the works themselves.
Last updated 2026-09-06
Typical duration
Typically 2-6 weeks of actual civils per site, but commonly stretched to twice that by phased bay releases, night working, permit windows and reinstatement guarantee requirements.
What is Civils & Groundworks?
The civils on a charging scheme are small in quantity and large in constraint. There is not much excavation, not much concrete and not much structure, and on an empty field a competent gang would be finished in a fortnight. But charging sites are almost never empty fields. They are forecourts, retail car parks, leisure centres, office estates and vehicle depots that go on trading, parking and operating throughout, and every metre of trench is somewhere a car drives, a pedestrian walks or a delivery lorry turns. The technical difficulty is low. The logistical difficulty is the whole job, and the phasing plan is effectively the design.
What actually gets built is a short list. A duct route from the supply position to the bays, with chambers and draw pits where the route turns or runs long. A base for each charging unit, and a compound or plinth for the substation, switchgear or distribution equipment. Bollards and kerbs to stop vehicles hitting units that cost more than the cars parked next to them. Drainage so the bays and the plant compound do not stand in water. Lighting and camera columns, because an unattended charging site used at night has to feel safe as well as be safe. Then surfacing, kerbing, markings, signage and reinstatement, which is the part the client and the public actually judge the job by.
Accuracy is where this package earns its keep. A charging unit is fixed to its base by cast-in fixings in a set pattern, takes its cable through an entry in a set position, and has a door that swings a set way. All of that comes off the charger supplier's general arrangement drawing, and on site that drawing is the specification. A base set to the wrong line, twisted a few degrees, or built with the duct stub coming up where the cable cannot reach the terminal, cannot be adjusted once it has cured. The unit is too heavy and too delicate to shuffle, the base has to be broken out and recast, and on a live site that means another closure, another traffic management set-up and another apology to the client. Set out from the grid, check it independently and check it again before the concrete goes in.
Compare the methods at a glance
When and why is Civils & Groundworks used?
The civils follow the design freeze and the accepted connection offer, and they run in a series of short, hard bursts rather than as one continuous operation. That pattern is not inefficiency; it is the price of working on a site that will not close. The client will typically release a handful of bays at a time, or a strip of car park, or one lane of a forecourt, and the works have to fit into that box, be made safe every evening and be handed back on the promised day. Nights and weekends are common because that is when a retail car park is empty and a depot fleet is out. Everything buried goes in during this stage and only this stage, because once the units are set and the bays are back in use there is no digging between them - which is exactly why the duct network is laid generously, proved before it is covered and surveyed as-built while the trench is still open. The commercial driver is the energisation date agreed with the distribution network operator. That date does not move for a wet week, so the civils are planned around it with the bases and ducts complete and proved well ahead, and the sequencing works towards handing the electrical team a finished, accurate, documented platform to build the installation on.
Types of Civils & Groundworks
Explore each method in depth - benefits, limitations, plant and quality control on its own page.
Open-cut trenching and reinstatement
The standard route: saw-cut or break out the surfacing, excavate, lay and surround the ducts, backfill and reinstate. Cheap, quick and easy to inspect while it is open, but it is disruptive across its whole length and the reinstatement is permanently visible, so the surfacing detail matters more than the trench does.
Explore this methodTrenchless crossings
Directional drilling, moling or thrust boring to get ducts under a road, a service yard, a mature tree, a watercourse or anything else that cannot be dug up. It removes the surface disruption entirely and often gets a route agreed that open-cut never would, at higher cost per metre and with less certainty about exactly where the bore ends up.
Explore this methodIndividual bases and kerbed plinth islands
A base per unit, or a raised kerbed island carrying several units and separating them from the bays. Islands protect the equipment, tidy the cable management and give somewhere to stand out of the traffic, at the cost of footprint and of losing part of a bay to the kerb line.
Explore this methodPlant compounds and hardstanding
The fenced or walled area holding the substation, switchgear or distribution equipment, with its own base, access, drainage and delivery route. Small in area and easy to underestimate, but it has to be reachable by the vehicle that will one day replace what is inside it, and its position is usually fixed by the network operator rather than by the designer.
Explore this methodBest suited for
- Trading forecourts and roadside sites where the works must fit between customers and hand back nightly
- Retail and leisure car parks released to the contractor in phases of a few bays at a time
- Depots and fleet bases where the works run around a vehicle operation that cannot stop
- Multi-storey and underground car parks where routes are constrained and excavation is limited or impossible
- Portfolio rollouts where a repeatable civils package is delivered across many similar sites
Civils & Groundworks: step by step
- 1
Step 1: Agree the phasing plan with the site operator before anything starts
The first document is not a method statement, it is a phasing plan agreed with whoever runs the site. How many bays can be taken at once, in which order, on which days, and handed back when. Where customers and staff will walk while the trench is open. How deliveries still reach the loading bay. Whether the works can run at night, and what the noise constraints are if they do. Which trading periods are untouchable. This gets signed off by the client, the site manager and, where relevant, the neighbouring occupiers, and it is what the programme is then built around. Teams that skip this step end up negotiating each closure on the morning it is needed, which is the slowest possible way to build anything.
- 2
Step 2: Set out the works and prove what is buried
The route, the bases, the chambers and the compound are set out from the site coordinate grid established during the survey, and the base positions are checked directly against the charger supplier's general arrangement rather than against an earlier layout drawing. Buried services along the route are re-detected and marked on the ground, and trial holes are dug by hand or by vacuum excavation at every crossing and at any point where the records and the detection disagree. The permit to dig is issued off that evidence. This half day of work is the single cheapest insurance on the project, because a service strike on a trading forecourt is not just a repair - it is an incident, an outage for the occupier and a very public one.
- 3
Step 3: Install traffic management, pedestrian routes and site protection
The working area is separated from the operating site properly, with barriers that will survive a car reversing into them rather than cones that walk away overnight. Vehicle routes, pedestrian routes and any accessible route diversions are set out and signed so a first-time visitor can follow them without thinking. Lighting is provided where the work runs into the dark. Excavations are covered or fenced whenever the gang is not working in them, and the site is left safe and tidy at the end of every shift rather than at the end of the phase, because on a live site the public arrives long before the gang comes back. Any temporary loss of accessible bays is agreed and replaced elsewhere rather than simply removed.
- 4
Step 4: Excavate the trench and lay the duct network
Surfacing is cut cleanly to line, the trench is excavated to the design, and ducts are laid to the route, separation and arrangement the designer has specified - the sizes, the spacing, the bedding and the surround all come off the drawing rather than off habit. Spare ducts go in at the same time, because on a live site the cost of an extra duct now is a fraction of the cost of a second trench later, and charging schemes get extended more often than any other kind. Draw ropes are installed, ends are capped, marker tape is laid as specified, and every duct is proved with a mandrel and rope before backfill so a blockage is found now rather than on the day of the cable pull. Nothing gets covered until it has been photographed and surveyed as-built.
- 5
Step 5: Construct the chambers, draw pits and plant compound
Chambers and draw pits are built at the positions the design shows, set to the finished surface level and with covers rated for whatever will drive over them, which on a forecourt or a depot is heavier than people assume. The plant compound base is constructed to the design and to the network operator's requirements where the operator will own or adopt what stands on it, including the access, the delivery route, the drainage and any bunding or containment the design calls for. Ducts entering chambers and the compound are sealed. Levels and falls are set by instrument, because a chamber that sits proud of the surfacing is a trip hazard on a public site and a chamber that sits low becomes a sump.
- 6
Step 6: Construct the charger bases and islands to the supplier's arrangement
This is the step that has to be right. Bases are excavated, blinded, reinforced and cast with the cast-in fixings, duct stubs and cable entry positions set exactly as the charger supplier's drawing shows, with the orientation of the unit - which way the door opens, which way the screen faces, which side the cable is dispensed from - fixed and marked before the pour. A template from the supplier is used where one is available rather than a set of dimensions transcribed by hand. Setting out is checked by a second person against the drawing and the grid before any concrete arrives. Kerbed islands are built to line and level around them, and the finished base levels and positions are surveyed and recorded after the pour so any discrepancy is known before the units are delivered, not discovered underneath one.
- 7
Step 7: Backfill, reinstate and surface
Trenches are backfilled and compacted in layers to the specification, and the surfacing is reinstated to whatever the site owner or the road authority requires for that surface - which on adopted ground is a defined specification with its own guarantee period, and on a private forecourt is usually a matter of matching what is already there well enough that the client cannot see the join. Reinstatement is the most visible part of the whole package and the part most likely to be judged a failure, because a trench line that settles or a patch that weathers differently sits in front of customers for years. Falls across the reinstated area are checked so water still runs where it always ran, and the surfacing around each base is finished so there is no lip for a trolley, a wheelchair or a charging cable to catch on.
- 8
Step 8: Complete the protection, drainage, lighting, markings and the handover of the ducts
Bollards, kerbs, wheel stops and any impact protection are installed where the design shows and, just as importantly, where they do not stop the unit being used - a bollard placed to protect a charger from a reversing van has ruined more bays than it has saved. Drainage is completed and proved to run. Lighting columns, camera posts and their ducting are installed and left ready for connection. Bay markings, accessible bay markings, directional signage and any tariff or wayfinding signage go down last. The package closes with a handover to the electrical team: duct routes proved and surveyed, base positions and levels recorded, chamber and compound as-builts issued, and a written list of anything that deviates from the design and has been agreed.
Plant & equipment
- Mini and midi excavators sized to work within a released bay area rather than an open site
- Vacuum excavation and hand digging tools for proving buried services
- Floor saws, breakers and planers for cutting into existing surfacing
- Vibrating plates, rollers and compaction equipment for backfill and reinstatement
- Site dumpers, grab lorries and muck-away arrangements suited to a trafficked site
- Concrete supply, formwork, vibrators and finishing tools for bases and islands
- Directional drilling or moling equipment where trenchless crossings are required
- Traffic management, barriers, temporary lighting and pedestrian barrier systems
Quality control & testing
- All setting out taken from the site coordinate grid and checked by a second person before any pour
- Base positions, orientations, fixings and duct stubs verified directly against the charger supplier's arrangement
- Buried services proved by trial hole before machine excavation, with the permit issued off that evidence
- Ducts laid to the specified route, spacing and surround, then proved with mandrel and draw rope
- Every buried route photographed and surveyed as-built while the trench is still open
- Backfill compacted in layers and reinstatement built to the specification the site owner or road authority requires
- Base levels and positions re-surveyed after casting and issued to the installation team
- Falls, cover levels and finished surfaces checked by instrument so water and wheels both go where intended
Safety watchpoints
- Working within a live, trafficked site with customers, staff and delivery vehicles moving around the works at all times
- Buried service strike - excavation only after detection, trial holes and a permit issued on proven information
- Excavation collapse, with support or battering as the temporary works design requires
- Public interface, including children, trolleys, wheelchair users and people who will step over a barrier rather than walk round it
- Hand-arm vibration and noise from breakers, saws and compaction plant on repetitive short-duration tasks
- Plant and pedestrian separation in a small working area where the machine and the gang share the same space
- Night and out-of-hours working, with the fatigue, visibility and lone-working risks that come with it
- Working near the site's existing electrical apparatus and supply position, which is entered only under the asset owner's control
Common defects to hunt
- Ducts blocked, crushed or laid to the wrong route, discovered on the day of the cable pull with the bays already back in use
- A base set to the wrong line or rotated, so the unit faces the wrong way and the door opens into a parked car
- Cable entries or duct stubs not aligned with the charger's entry position, leaving the cable unable to reach its termination
- Base or island levels set so that surface water ponds against the unit or runs into the chamber
- Trench reinstatement settling or weathering differently, leaving a visible scar across a customer car park
- Bollards and wheel stops positioned so that a bay cannot be used properly or the charging cable will not reach the vehicle
- Chamber covers set proud or low, or rated for the wrong loading for the vehicles that actually cross them
- No as-built record of the duct network, so the next phase digs speculatively through what has just been built
How long does Civils & Groundworks take?
Typical duration: Typically 2-6 weeks of actual civils per site, but commonly stretched to twice that by phased bay releases, night working, permit windows and reinstatement guarantee requirements..
Related processes
- Site Survey & Grid Application
- Electrical Infrastructure
- Charger Installation
- Commissioning & Energisation
- Open-cut trenching and reinstatement - method
- Trenchless crossings - method
- Individual bases and kerbed plinth islands - method
- Plant compounds and hardstanding - method
- EV Charging Infrastructure sector guide
- Utilities & Energy - group of sectors