One consent. Compulsory purchase powers, planning permission, listed building consent, highway works authority – all in a single document.

A Development Consent Order is how a Nationally Significant Infrastructure Project actually gets permission to be built. It’s a single instrument that can carry an enormous amount of legal weight, and for anyone with land in a scheme’s path, knowing how the process works – and when to get involved – matters a great deal.

Here’s how a DCO is granted, what it can contain, and what it means for landowners along the way.

What is a DCO?

Introduced by the Planning Act 2008 in the wake of the protracted Heathrow Terminal 5 inquiry, the Development Consent Order was designed to replace a patchwork of separate applications – planning permission, compulsory purchase order, listed building consent, highway authorisations – with a single order covering everything a project needs. Rather than an applicant seeking each consent from a different body, one DCO application, examined by the Planning Inspectorate and decided by the Secretary of State, can grant the lot at once.

That consolidation is the whole point of the regime: fewer processes, one timetable, one decision.

What can a DCO actually contain?

Beyond planning permission for the development itself, a DCO can include powers relating to highway works, discharging water, surveying and investigating land, protecting buildings, felling trees and removing hedgerows, extinguishing or diverting public rights of way, and – significantly – land acquisition powers, including compulsory acquisition, the power to override easements, and the power to take temporary possession of land during construction.

In effect, a single DCO can do the legal work of several separate consents and orders that would otherwise each need their own application, their own consultation, and their own decision-maker.

How is a DCO granted? The six stages

The process runs through six defined stages, each with its own statutory timescale: pre-application, acceptance, pre-examination, examination, decision, and post-decision. It’s a front-loaded process – the applicant must fully scope the scheme and consult widely, including with statutory consultees, local authorities, landowners and tenants, and the public, before the application is even submitted for acceptance.

Once accepted, the Planning Inspectorate examines the application, typically over a period of months, before making a recommendation to the relevant Secretary of State, who takes the final decision. Government’s target for the whole process, from acceptance to decision, is around 12 to 15 months – a significant reduction from the multi-year timescales that preceded the 2008 Act.

How do you get a say?

Relevant local authorities automatically become Interested Parties. Anyone else – a landowner, a tenant, a member of the public – has to formally register as an Interested Party during a minimum 28-day registration window, which is what gives someone the right to submit written representations and request to speak during the examination. Missing that window is a real risk: registration isn’t a formality, and someone directly affected by a scheme who doesn’t register in time can lose their formal route to be heard.

What about compulsory acquisition specifically?

Sections 122 to 134 of the Planning Act 2008 set out both the ability to include compulsory acquisition powers within a DCO and the specific conditions that must be satisfied before those powers can be granted. A DCO’s compulsory acquisition function is legally separate from its planning function – the two are assessed against different tests, even though they’re delivered through the same order. Where the conditions are met, this route avoids the applicant needing to seek a separate, standalone compulsory purchase order.

How is this different from a standard CPO?

A conventional compulsory purchase order is a standalone process for one scheme, brought by one authority, under its own dedicated legislation. A DCO’s compulsory acquisition powers are one element within a much larger, bundled consent – so land might be compulsorily acquired as an incidental part of a decision that’s primarily about granting planning permission for the wider infrastructure scheme, rather than through a process that was ever solely about the acquisition itself.

Why does this matter for a transaction?

Because so much is decided within a single order, a DCO can affect a property in ways that wouldn’t show up through the usual routes: not just planning permission for a scheme nearby, but compulsory acquisition, rights of way extinguished, or temporary possession of land during construction, all authorised at once. As with NSIPs generally, this sits with the Planning Inspectorate’s national register rather than local authority planning records, so it’s a case where the standard local search won’t necessarily be the tool that reveals it. For any property near a proposed NSIP, checking the national infrastructure register – and understanding the Interested Party registration window if a client wants to have any say – is worth doing well before examination gets underway.

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A DCO isn’t just a bigger planning permission. It’s a fundamentally different legal instrument, capable of granting compulsory acquisition powers, rights of way changes, and construction authorisations all in one document.

For anyone with land near a proposed NSIP, understanding what a DCO can do – and how narrow the window is to formally take part – matters well before a decision is ever made.

Some properties aren’t blighted by what’s happened. They’re blighted by what might.

A road scheme is proposed. A compulsory purchase power exists but hasn‘t been used. The property sits in limbo – too affected to sell at a fair price, not yet acquired by anyone. The blight notice exists for exactly that gap, and it works in a direction most people don’t expect: it lets the owner force the authority to buy.

Here’s how it works, and why it’s sometimes called “reverse compulsory purchase.“

What is a blight notice?

Sections 149 to 171 of the Town and Country Planning Act 1990 allow a person with a qualifying interest in certain categories of land to require the relevant authority to purchase that interest. Rather than the authority initiating acquisition, as it would under a compulsory purchase order, the owner initiates it themselves. That reversal of the usual sequence is why the mechanism is commonly described as reverse compulsory purchase.

It exists to relieve a specific kind of hardship: land can become effectively unsellable, or only sellable at a heavily discounted price, once a planning or highway proposal makes clear that it may eventually be acquired or affected – long before any actual scheme, or any CPO, materialises. Without the blight notice route, an owner could be left in limbo for years, unable to sell at a fair price and with little certainty about when the position will be resolved.

What counts as “blighted land”?

Not every property near a proposal qualifies. The land has to fall within one of the specific categories set out in Schedule 13 of the Act – a list significantly amended by the Planning and Compulsory Purchase Act 2004 – which covers things like land allocated in development plans for public authority functions, land affected by highway schemes at defined stages, land within new town or urban development designations, and land where compulsory purchase powers exist but haven’t yet been exercised.

Being near a general area of planned change isn’t enough. The land has to sit within one of the defined statutory categories, which is a narrower test than it might first appear.

Who can serve one?

The right is limited to owner-occupiers, not investors or landlords generally. In practice that means: an owner-occupier of a private dwelling, an owner-occupier of business premises below a set rateable value threshold, an owner-occupier of an agricultural unit, a mortgage lender with the power to sell and give immediate possession, or the personal representative of someone who would have qualified before their death.

What do you have to show first?

Beyond the property falling within a blighted land category and the claimant holding a qualifying interest, the owner generally has to show they made reasonable efforts to sell the property and could only do so, if at all, at a price substantially lower than it would fetch without the blight. That “reasonable endeavours to sell” test sits at the heart of most claims.

There’s an exception. Where the relevant compulsory purchase powers remain exercisable over the land, the owner doesn’t need to demonstrate a failed sale attempt at all – the notice can proceed on that basis alone.

What happens once a notice is served?

The authority can accept the notice, or serve a counter-notice objecting to it on specified statutory grounds within two months. If the owner disagrees with a counter-notice, or with a rejection, they can refer the matter to the Upper Tribunal (Lands Chamber) within a further two months. Where a blight notice takes effect – whether by acceptance, tribunal determination, or the authority simply not responding in time – the authority becomes bound to purchase the interest, and compensation is assessed broadly as if the land had been compulsorily acquired.

How is this different from a Part 1 Land Compensation Act claim?

The two sit at opposite ends of the same problem. A Part 1 claim is made after public works are built and in use, for depreciation caused by their operation – noise, vibration, and the like – with no land changing hands. A blight notice is available before anything is built, in some cases before any scheme is even confirmed, and forces the outright purchase of the land itself rather than compensating for a fall in value while ownership continues.

Put another way: Part 1 compensates you for staying put next to something that now exists. A blight notice gets you out from under something that might.

Why does this matter for a transaction?

For a seller, a blight notice may be the only realistic route to a fair sale if a proposal has made the property genuinely unsellable on the open market. For a buyer, it’s worth knowing whether a seller has already served, or is eligible to serve, a blight notice on a property affected by a nearby scheme – because the availability of a blight notice can depend heavily on who owns and occupies the property at the relevant time, making timing an important consideration

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Blight notices are a narrow, procedural remedy – but where a genuine Schedule 13 designation applies and a sale has failed because of it, they can be the difference between years in limbo and a fair, timely purchase.

Anywhere a planning or highway proposal has cast a long shadow over a property without yet delivering a scheme or a CPO, it’s worth asking whether that shadow meets the statutory test.

Some developments are too big for the local planning system to decide on at all.

A new power station, a major rail scheme, a large reservoir – projects on this scale don’t go through the local authority’s planning committee. They bypass it entirely, decided instead by central government under a completely separate regime. That regime is Nationally Significant Infrastructure Projects (NSIPs), and understanding why a scheme sits inside it changes where you’d even look to find out about it.

Here’s what makes a project an NSIP, and why that matters for anything nearby.

What is an NSIP?

The Planning Act 2008 created a distinct category of large-scale development in five sectors – energy, transport, water, waste water, and waste – that qualify as Nationally Significant Infrastructure Projects once they exceed defined statutory thresholds. An onshore generating station over 50 megawatts is a typical example of a threshold test; similar size- or capacity-based tests apply across the other sectors, covering things like electricity generating stations, rail freight interchanges, reservoirs, and hazardous waste facilities.

Since 2013, business and commercial projects that don’t automatically meet a sector threshold can also opt into the regime if the Secretary of State considers them nationally significant, so the category isn’t purely a function of the thresholds; there’s a discretionary route in as well.

Why does size change who decides?

Once a project meets the NSIP threshold, it no longer goes through the local planning authority for permission. Instead, the applicant applies to the Planning Inspectorate, which examines the proposal and makes a recommendation to the relevant Secretary of State, who takes the final decision. This has been the arrangement since April 2012, when the Planning Inspectorate took over the role from the former Infrastructure Planning Commission following the Localism Act 2011.

The logic is straightforward: projects of this scale often cross multiple local authority boundaries, involve national policy priorities that a single council isn’t well placed to weigh, and benefit from a single, consistent consenting process rather than a patchwork of separate local decisions.

What happens to the local authority’s role?

It doesn’t disappear, it changes shape. A host or neighbouring local authority becomes a statutory consultee rather than the decision-maker, and is required to produce a Local Impact Report during the examination stage, setting out the effects the project will have on its area. That report feeds into the Planning Inspectorate’s recommendation, but the authority no longer has the power to grant or refuse permission itself.

How is an NSIP actually authorised?

Through a Development Consent Order (DCO), a single consent that can bundle together permissions that would otherwise need to be applied for separately, including elements of compulsory acquisition. The process from formal acceptance of an application to a decision typically takes over a year, and is front-loaded with substantial pre-application consultation requirements before the Planning Inspectorate will even accept a submission. The mechanics of the DCO process – and what it means for landowners along a scheme’s route – are worth a piece of their own, given how much they involve.

Why does this matter for a property search?

Because an NSIP bypasses the local planning authority, the usual channels a conveyancer relies on for planning history don’t necessarily surface it in the way they would a conventional planning application. A DCO application sits with the Planning Inspectorate’s national register, not the local authority’s planning portal, and a standard local search isn’t necessarily designed to highlight a nationally significant scheme progressing through a separate, centrally administered process.

For any property near a proposed energy, transport, water, or waste scheme of real scale, that’s a reason to check the national register specifically rather than assuming a clean local search means nothing of consequence is coming. It’s also the route by which some of the most substantial compulsory acquisition and blight issues arise – an NSIP’s DCO can carry powers that touch a much wider area than the footprint of the scheme itself.

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An NSIP isn’t defined by controversy or local objection, it’s defined by scale, sector, and a statutory threshold that moves the decision out of local hands entirely.

Knowing a project qualifies as an NSIP tells you immediately where to look for information about it, and it’s rarely the place a standard search would otherwise point you.

A new road opens nearby. Nothing is built on the property; no land is taken… and yet its value can still fall.

Part 1 of the Land Compensation Act 1973 exists for exactly that situation. It’s a compensation right most conveyancers rarely encounter, precisely because it doesn’t involve land being acquired at all – but for properties near new or altered infrastructure, it can matter a great deal.

Here’s what a Part 1 claim actually is, and why it’s a different animal from compulsory purchase.

What is a Part 1 claim?

Where the value of an interest in land is depreciated by physical factors caused by the use of public works, the person with that interest can claim compensation from the authority responsible for the works. This is known as a Part 1 claim, after the part of the 1973 Act that creates the right.

Crucially, no land needs to be taken from the claimant for a Part 1 claim to arise. It’s a form of injurious affection; value lost through the presence and operation of nearby infrastructure, not through anything physically removed from the property. The legislation provides a route to compensation in circumstances where an affected owner may otherwise have limited remedies for depreciation caused by the use of public works.

What counts as a “physical factor”?

The Act sets out a fixed, exhaustive list: noise, vibration, smell, fumes, smoke, artificial lighting, and the discharge of any solid or liquid substance onto the land. Nothing outside that list qualifies, however genuinely a property’s value has been affected – general loss of view, disruption during construction, or a change in character to the area won’t support a claim on their own.

The factors also have to result from the use of the works, not their construction or their mere existence. A new road causing traffic noise can qualify; the fact of a road having been built at all doesn’t.

What counts as “public works”?

The Act covers three categories: any highway, any aerodrome, and any other works or land provided or used under statutory powers – which in practice extends to a wide range of infrastructure delivered by public bodies, from road schemes to certain utility and transport works. Although the statutory responsibility sits with the relevant authority, funding arrangements behind infrastructure schemes can be more complex.

When can a claim be made?

Timing is tightly defined by statute. The “relevant date” is the date a highway first opened to public traffic, or the date other public works were first used after completion. There is a statutory time limit for claims after the relevant date, after which the right may be lost.

There’s a practical logic to the delay before a claim can be brought at all: a claim reflects how a hypothetical buyer would value the property once the works are up and running and their effects can be properly assessed, not a prediction made before anyone knows how the finished scheme will behave. Compensation also isn’t available for factors caused by accidents involving vehicles or aircraft, and generally only one claim can be made per scheme, regardless of later changes in ownership.

How is this different from compulsory purchase compensation?

Compulsory purchase compensation is paid because land has been acquired. A Part 1 claim is paid because land value has fallen, even though nothing has been acquired at all – the two sit either side of a clear line. It’s entirely possible for one property on a scheme to be subject to a CPO, and its neighbour, unaffected by the CPO but sitting beside the finished road, to have a Part 1 claim instead.

Why does this matter for a transaction?

For most properties, this is background law that never becomes relevant. But for anything near a recently completed or altered road, aerodrome, or comparable public works scheme, it’s worth knowing whether a Part 1 claim has already been made and settled on the property – because that can affect whether a further claim is available, and it’s a piece of history a seller may not think to mention unprompted. A buyer relying on a mortgage valuation is unlikely to have this flagged for them; it’s the kind of thing that surfaces through local knowledge, targeted enquiries, or awareness of a nearby scheme’s timeline rather than a standard search return.

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Part 1 of the Land Compensation Act 1973 is a narrow, specific right, one fixed list of physical factors, one class of public works, and a limited window to claim. But where it applies, it’s often the only compensation route available to an owner whose land hasn’t been touched but whose value has been affected regardless.

For any property near a completed or upcoming infrastructure scheme, it’s worth asking the question rather than assuming a clean search means nothing to consider.

Most CON29 questions ask about one thing.

Question 3.7, however, asks about six and the answer often can’t be found on a public register at all. Outstanding Notices is the CON29’s catch-all, and one of its least understood entries.

Here’s what it covers, why it exists, and why answering it sometimes means looking beyond the standard search return.

What is the Outstanding Notices question?

CON29 question 3.7 asks whether any statutory notices subsist in relation to the property – other than those revealed anywhere else on the form – relating to building works, environment, health and safety, housing, highways, public health, or flood and coastal erosion risk management.

That “other than those revealed anywhere else” is the important part. Every other question on the CON29 is defined by what it is: planning decisions, road schemes, conservation areas, contaminated land. Outstanding Notices is defined by what it isn’t. It exists to catch anything statutory and notice-shaped that the rest of the form wasn’t built to ask about.

Why does it span so many different areas?

Because it isn’t really one question – it’s six, folded into a single line. A notice under housing legislation has nothing to do with a notice under the Highways Act, which has nothing to do with one under public health law. The only thing they share is that they are all formal statutory notices affecting the property… and none of them fit anywhere else on the form.

That breadth is exactly why the question matters. A house can pass every other CON29 enquiry cleanly and still be subject to a housing or public health notice that has not been revealed elsewhere on the form.

Why can’t it always be answered from a public register?

Most CON29 questions are answered from a single, well-established local authority register. Outstanding Notices often isn’t, because the underlying notices sit with different departments entirely – building control, environmental health, highways, housing – each keeping its own records for its own statutory purpose, not for conveyancing.

Some councils are explicit that parts of question 3.7 are not held on a public register and may require separate enquiries with the relevant department, at an additional cost and with its own turnaround time. That’s a meaningful practical difference from a question like Conservation Areas, where the answer sits in one place and comes back with everything else.

How is this different from planning enforcement notices?

It’s easy to conflate Outstanding Notices with the CON29’s planning enforcement question, but they’re separate enquiries covering separate legal territory. The planning enforcement question deals specifically with action taken under the Town and Country Planning Act and related legislation – enforcement notices, stop notices, listed building enforcement notices, and similar instruments tied to planning control.

Outstanding Notices doesn’t touch planning enforcement at all. It’s about notices arising under entirely different statutory regimes – housing, public health, highways, building control – that are all created through different pieces of legislation but share the same basic mechanism. Two conveyancers could reasonably describe both as “a notice on the property” and be talking about completely different things.

What does this mean in practice?

Because the question is residual and multi-departmental, the honest, but frustratingly vague and bureaucratic answer to “how long will this take” and “what will it cost” is: it depends on what’s being asked and who holds it. Where the information isn’t on a public register, conveyancers should expect an additional request may be needed, with its own fee and timescale, separate from the standard search return.

For anyone advising a buyer, the practical takeaway is simpler: a notice under one of these six headings won’t necessarily show up anywhere else on a clean-looking search. Where a property’s age, location or recent history raises the possibility of a housing, highways or public health notice, conveyancers may wish to satisfy themselves that question 3.7 has been fully answered – not just assumed clear because nothing else flagged.

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Outstanding Notices isn’t a gap in the CON29 – it’s the form’s safety net, catching six different types of statutory notice that don’t belong anywhere else. It’s also one of the entries most likely to need a separate, additional enquiry before it can be answered with confidence.

A clean result elsewhere doesn’t guarantee Outstanding Notices is clear. That’s exactly why question 3.7 exists.

^{By Elizabeth Jarvis, Managing Director, OneSearch}

I read recently about a term in psychology called the ‘normalisation of deviance’. It describes what happens when teams repeatedly encounter a problem, nothing catastrophic comes of it, and so the problem gradually becomes accepted as the norm.

The deviation from the standard becomes the standard.

It happens in conveyancing practices all the time, and search provider relationships are one of the most common places it takes root.

You chase an update. Nothing terrible happens. You chase again the next time. Still nothing terrible. After a while, chasing is just part of the process. The deviation – your provider not updating you proactively – has become normalised. And the energy you spend managing around it has become invisible, because it’s been absorbed into the rhythm of your working day.

This is what I’d call the ‘Cost of Quiet Stress’. And unlike the obvious costs in legal practice, things like missed deadlines, errors, complaints… it rarely appears on anyone’s radar because it never quite crosses the threshold that would force a response.

But it has a real impact; on your time, on your focus, on the cognitive load your team carries through every transaction. And if you’ve just completed our search provider scorecard, your results are partly a measure of how much of it you’ve been absorbing.

What each category is really measuring

Let me take you through the six categories – not just what the questions ask, but what the underlying scores are actually telling you.

Data accuracy: do you have a reason for confidence, or just an absence of evidence.

Low confidence in data accuracy doesn’t always mean you’ve experienced problems. More often it means you don’t have enough visibility into the process to be sure either way.

There’s an important distinction between a provider who hasn’t caused you a problem yet, and one who has systematic verification built into their process. The former gives you hope, the latter gives you grounds for confidence. If you can’t explain why you trust your provider’s data – if the honest answer is “we haven’t had issues” – that’s worth examining.

Turnaround times: is your confidence based on consistency or just recent luck?

A fast average turnaround is less valuable than a predictable one. What creates the Cost of Quiet Stress in this category isn’t the occasional delay – it’s the background uncertainty about whether you can plan around your provider when it matters.

Everyone talks about speed; the more useful question is reliability. If you scored well here, consider whether that’s based on a consistent pattern you could describe with confidence, or on the fact that it hasn’t been seriously tested recently.

Customer service: partner or supplier.

This is the framework I come back to most often.

Suppliers process orders. They respond to queries. They resolve problems when raised. Partners do all of that – and they anticipate, they flag, they stay in contact without being prompted. They treat your problem as their problem before you’ve had time to begin stressing over it.

The distinction is invisible when everything runs smoothly. It becomes very visible (not to mention very consequential) when something doesn’t.

Account management: the relationship that should exist but often doesn’t

Of all six categories, this is the one with the biggest gap between what firms typically experience and what they could reasonably expect.

Genuine account management means someone who knows your firm well enough to notice when something has changed; in your caseload, in your market, in the regulatory environment you’re operating in, and brings relevant information to you before you’ve had to ask.

If the only time you see your account manager’s name is on a Christmas card or an auto-renewal notice… you don’t have a relationship, you have a pen pal.

Search pack completeness: the risk that’s invisible until it isn’t

The normalisation of deviance is particularly acute here. Firms order what they’ve always ordered. Transactions complete. Nothing catastrophic happens. The assumption that the pack is appropriate hardens into habit, even as caseloads evolve and the landscape around specific transaction types changes.

A strong score here reflects active review – either by you, or prompted by a provider who flags relevant additions. A weaker score often reflects an assumption that hasn’t been examined recently.

Value and confidence: what is quiet stress actually costing you.

The final category gets closest to the real question. Not whether your provider is delivering to a minimum standard, but whether they’re giving you genuine confidence – the kind where you advise clients knowing the data behind you has been properly verified.

That confidence has a value that doesn’t appear on an Excel spreadsheet. Its absence shows up in extra checking, in slightly more cautious advice, in the cognitive overhead of holding a low-level background uncertainty through every transaction.

Across a full working week, across a full team, that overhead is not trivial.

The standard worth measuring against

To make this concrete, here’s a simple way to think about what you should be expecting versus what many firms have normalised:

 The ‘Cost of Quiet Stress’ lives in the gap between those two columns. It’s real, it’s cumulative, and it’s optional.

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What to do with your result

If your score was strong across the board – genuinely, not just in the absence of problems – the main thing is to keep asking the questions. Provider quality drifts. The firms who notice earliest are the ones who check periodically rather than assuming continuity.

If your score flagged gaps, particularly in data accuracy, account management, or customer service, those are worth a proper conversation. Not a presentation. An open chat around your specific situation – what you’re currently getting, what you’re not, and whether the gap is worth closing.

That’s what our search pack review is. Straight talking, no agenda beyond giving you a clearer picture.

The cost of quiet stress is real. But it’s also optional.