Heat network pipe routes and the highway consents needed

A heat network operator is not automatically a statutory undertaker, so it has no inherent right to dig up the road. Where the distribution pipework leaves your red line, the usual route is a street works licence under section 50 of the New Roads and Street Works Act 1991 from the street authority, plus a permit for each set of works, plus an easement or wayleave over any third party land the route crosses. Heat network pipe highway consent is therefore three consents rather than one, and none of them is granted by the planning authority.

That matters at application stage because an officer asked to accept a connection commitment will want to see that the route is deliverable. A line on a drawing crossing six ownerships is not evidence.

Why the route is a planning issue

Energy policy pushes major development towards network connection. In London, the London Plan heat network policies require major schemes to connect to an existing network, or to a planned one, or to be designed so they can connect later, following the heating hierarchy. Authorities outside London apply similar policies through adopted local plans and through the energy statement.

So the connection becomes part of the planning balance, and a condition will secure it. The condition has to be capable of being complied with, which is where the route comes in. An authority cannot lawfully impose a condition requiring something that is plainly undeliverable, and an applicant cannot rely on a commitment it has no legal means to perform.

Set out the route, the consents needed and the programme inside the Energy Statement, with a plan showing ownerships and the highway boundary. That single plan resolves more consultation correspondence than any amount of narrative.

Street works permits and the highway authority

Two separate things are needed from the street authority. A licence that allows the apparatus to be placed and kept in the street at all, and a permit that allows each physical excavation to take place at a particular time.

The section 50 licence names the licensee, defines the apparatus and the extent of the street, and imposes conditions on maintenance and liability. The licensee takes on duties similar to those of an undertaker for the life of the apparatus, including liability for reinstatement and for future works. Licences are transferable with consent, which matters where the network will be sold to an operator after completion.

Permits sit under the permit scheme operated by the street authority under the Traffic Management Act 2004 framework. Each permit specifies the works, the duration and the traffic management, and the authority can refuse or vary it to coordinate with other works. On a traffic-sensitive street the permitted working window may be nights only, or school holidays only, which changes the cost and the programme rather than the principle.

Reinstatement follows the national specification, with a guarantee period after completion during which the licensee remains liable for failures. Check the current specification and the authority's own requirements, since both are revised.

Easements across third party land

Any part of the route outside the public highway and outside your ownership needs a property right. A deed of easement registered against the burdened title is the durable answer. A wayleave is quicker and usually terminable, which is fine for a temporary arrangement and poor for a thirty year asset.

Identify the ownerships early from title plans rather than from assumption. The crossings that cause delay are predictable:

• railway land, where a crossing needs the infrastructure owner's asset protection process and its own agreement
• canal and river land, with a separate consent regime and its own charges
• private estate roads and unadopted streets, where ownership is often unregistered or fragmented
• land subject to agricultural tenancies, where the tenant's consent and compensation are separate from the freeholder's

Where ownership cannot be established, say so in the submission and propose an alternative route. Authorities respond far better to an identified problem with a stated fallback than to silence followed by a discharge of conditions application that cannot be made.

Grampian conditions for off-site works

Where the works are outside your control, the standard mechanism is a negative condition preventing occupation until the off-site works are complete. That approach takes its name from the Grampian case, and it is acceptable in principle provided there is a reasonable prospect of the works being delivered.

Reasonable prospect is the test to evidence. A heads of terms with the network operator, a letter from the landowner confirming willingness to grant an easement, or a pre-application response from the street authority on the licence all help. Where the prospect is remote, the condition is unlikely to save the application, and the honest course is to design the scheme to work without the connection while safeguarding the route for later.

Safeguarding wording needs care. A condition requiring the building to be constructed so that it can connect to a future network should specify what that means in practice, usually a plant room with space and structural provision for heat exchangers, capped connections at the site boundary and a hydraulic design compatible with lower flow temperatures. Conditions that secure future infrastructure without describing it tend to be discharged with a drawing nobody checks. The same problem arises with charging infrastructure, and how electric vehicle charging is secured by planning conditions shows the drafting that works.

Programme and reinstatement

Build the consents into the programme as a sequence rather than a block. The licence application precedes the permit, the permit precedes the works, and the works precede connection and commissioning. Each step has a determination period set by the authority.

Reinstatement is the step that overruns. Interim reinstatement followed by permanent reinstatement is common on busy streets, and the second visit needs its own permit. Where the route crosses a recently resurfaced street, the authority may impose additional requirements, and some authorities apply restrictions on opening a street for a period after substantial resurfacing.

Tree roots are a frequent late obstacle. A route through a verge or footway with mature street trees runs into root protection areas, and the highway authority and the authority's tree officer may both have a view. Trenchless techniques solve it at a cost. Survey the route for trees at the same time as the utility searches, not afterwards.

Phasing connections to occupation

On a phased scheme the connection obligation should be phased too, and the drafting should match the physical network. A condition requiring connection before first occupation of phase one, where the energy centre is in phase three, is a condition that cannot be met.

The workable structure is usually a temporary heat source for early phases, with a condition requiring transfer to the network by a stated trigger, and a corresponding obligation in the agreement. Make the trigger something within your control, and keep the temporary plant removable in practice rather than a permanent boiler house that will never be decommissioned.

Interaction with the construction phase matters as well, because trenching in the highway and construction traffic compete for the same road space. Describe both in the Construction Traffic Management Plan so the highway authority sees one coordinated picture.

Evidence of deliverability

Five documents carry the argument, and an officer will look for all of them on a scheme where network connection is a policy requirement.

A route plan at a legible scale showing the highway boundary, the ownerships crossed and the proposed method at each crossing. A land ownership schedule with title numbers. Correspondence with the network operator covering capacity and a programme. A pre-application response from the street authority on the section 50 licence. And a capacity and connection position from the other utilities, which belongs in the Utilities Assessment alongside electricity and water.

The statutory framework here is moving. The Energy Act 2023 introduced regulation of heat networks and a zoning framework for England, with much of the detail left to regulations, so check which provisions are in force before relying on a zoning designation or on any new powers for operators. The position stated here is as at the latest published position on which provisions are in force, and it should be verified on legislation.gov.uk at the time you write your submission.

PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval. This article is general guidance rather than legal advice on a particular route or agreement. Enter your postcode on PlanScope to see which reports your site is likely to need.