Data Centre Site Survey: Utilities, Fibre and HT Feeds

What should a data centre site survey include below ground?

It should cover three things underground: the plot itself, the two fibre paths to the building and the HT power feed from the grid substation. Each one can delay commissioning if it is left to the construction stage. A water main under a planned generator yard costs months. A fibre route sharing a culvert with its twin, or an HT trench blocked by a gas line, costs as much.

Most developers commission topographic and soil work early but treat utilities as a detail. For a building whose whole value depends on power and connectivity that never fail, the routes those services take outside the fence matter as much as the design inside it.

Dual fibre route survey: are the two paths separate?

A dual fibre route survey walks and scans both planned paths end to end and reports every point where they come close, share a structure or cross the same hazard. Diverse routes look separate on a map but often meet in practice. They share a road bridge, a culvert, a service lane or a single manhole near the gate.

• Shared structures: bridges, culverts, rail crossings and flyover approaches where both routes are forced together.
• Common ducts: telecom duct banks along main roads that both carriers plan to use.
• Entry points: the last few hundred metres into the campus, where routes often converge on one gate.
• Third-party risk: stretches beside drains, road widening or metro work where both routes could be cut by the same excavation.

We give the minimum separation measured along each stretch and mark the pinch points on a drawing, so the design team can decide where a route needs to move. Each path is scanned with radar along its full length, with locators at road crossings and existing telecom ducts. Ground penetrating radar (GPR) sends electromagnetic waves down from a moving antenna, and every duct, pipe or culvert wall shows as a reflection in the return signal.

The survey also helps with carrier negotiations. With a cleared, separated pair of routes and the obstacles listed, carriers can price and build to it. They do not need to propose paths that later prove less diverse than claimed.

What hides under a greenfield data centre plot?

Plots bought from farmland or older industrial estates rarely arrive clean. Typical finds are irrigation pipes, borewell lines, old wells filled with debris and village water mains along the boundary. Abandoned cables and old drains are common too, and each buried object goes on the plot drawing. Any of these can sit under a planned generator yard, transformer pad or tank foundation. A grid scan before the layout is frozen lets the design move around them, which is far more cost-effective than digging them out later.

HT cable route survey from the grid substation

Large campuses take power at high voltage, often through two incomers from different sources, and both cable routes need the same scrutiny as the fibre. An HT cable route survey traces existing cables, pipes and drains along the planned trench, checks the crossings of roads and drains, and finds space for the joint bays.

The results show whether the trench can reach its design depth and where it must dip under or rise over existing services. They also show where trenchless crossings beat open cut. Long rural sections, where the cable runs along field edges and village roads, often hide unrecorded water and irrigation lines. Our approach to these routes is described under what we do: HT/LT cable route survey.

Inside the campus: duct banks, earthing and plant yards

On brownfield plots and running campuses, the survey shifts to the utility lines between buildings. These include duct banks, earthing grids, chilled water, generator fuel lines, storm drains and fire mains. Expansion phases are where strikes happen. A new hall goes up next to a live one, and its piling and trenching take place a few metres from cables that carry the existing load.

We scan the footprint and connection routes of each new phase, mark live services on the ground and update the campus underground utility mapping. That drawing, kept current, becomes part of the site's change process; the formats and GIS options are covered in more on CAD and GIS utility mapping.

What is different in Noida, Navi Mumbai and Chennai?

Each of the main data centre clusters brings a different underground picture, and the survey plan is adjusted to it.

• Noida and Greater Noida: large planned sectors with wide roads and service lanes, but heavy recent construction along the expressways means new cables and pipes laid ahead of the records.
• Navi Mumbai: industrial estates with dense older services, high monsoon groundwater and, near the creek, softer and wetter ground conditions that reduce radar depth.
• Chennai: a cluster drawn partly by submarine cable landings on the coast, with long fibre routes inland, sandy coastal soils and flood-prone low ground along some corridors.

Whatever the city, the basic discipline of confirming owners and records before any excavation applies. For background reading, our article explains how that works in India.

When in the project should the survey be done?

Before the site layout is frozen and before carriers or the power utility are given their routes, during land due diligence or concept design. At that stage moving a generator yard or a route costs a line on a drawing. After piling starts, the same change can mean redesign, delay and a new approval.

1. Due diligence: a quick plot scan and a check of the most likely fibre and power corridors, to flag any deal-breakers.
2. Concept design: full route surveys of both fibre paths and the HT feed, with separation and crossing data.
3. Before construction: footprint scans and ground marking for each phase, repeated for later expansion halls.

Data centre utility survey at a glance

The main parts of a typical data centre survey are summed up below.

For plot work before piling, see how pre-excavation scanning clears each footing location.

How much does a data centre route survey cost?

Route scanning is priced by length: ₹24 per metre for a standard GPR scan or ₹32 per metre when L-sections are needed, with GST added. As an example, two diverse fibre paths of 8 km each make 16,000 metres; at the standard rate that is ₹3,84,000 plus GST. The minimum order is ₹50,000 inside Delhi NCR, which covers Noida and Greater Noida, and ₹1,00,000 elsewhere.

Developers surveying many routes for one construction project benefit from whole-order discounts: 25% above 100 km, 40% above 500 km and 50% above 1,000 km. The complete card is on our GPR survey price list. On NCR campuses, scanning normally opens on order day, one business day being the longest wait. Share the plot location and the planned routes and request a written estimate.

Frequently asked questions

Can you measure the separation between two fibre routes?

Yes. We report the measured distance between the two paths along their length and list every stretch where they come closer than the separation your design asks for.

Do you survey the carrier's route or ours?

Either. We can survey the routes your carriers propose, or survey alternatives first so you can give carriers a cleared path.

Can GPR find HDPE ducts with fibre inside?

In most soils, yes. Empty or cable-filled HDPE ducts show on radar, which detects metallic and non-metallic objects alike. Where a tracer wire or marker exists, locators confirm the line.

Can you work on a live campus?

Yes. We follow the site's access and change rules, keep clear of critical rooms unless invited, and scan around live duct banks with locators as well as radar.

What if the route crosses a highway or railway?

We scan the crossing, list services in the way and note depths from the data collected. The crossing can then be designed and approval sought from the road or rail owner.

What do you need for a quote?

The plot location, the two fibre paths and the HT route as KMZ or marked maps, and the planned start date.

Written by Saniya Parveen · Technically reviewed by Rahul Rai · Updated 8 November 2026