Green Infrastructure Plan: section by section

A Green Infrastructure Plan is the document that shows what green and blue features a scheme provides, what functions each one performs, and how the whole network connects to what exists beyond the red line. Its distinguishing feature is quantification. Where a landscape strategy describes character and planting intent, a green infrastructure plan structure is built around numbers: areas by typology, canopy cover, permeability, connectivity and the standards those figures are being measured against.

Councils increasingly ask for it on major schemes, and the version that works is the one that can be checked.

Baseline green infrastructure and connectivity

Start with what is there. Map the existing green and blue features on and adjacent to the site: trees and groups, hedgerows, grassland, scrub, watercourses, ponds, verges, gardens and any structural planting. Record the area of each, the canopy cover as a percentage of the site, and the proportion of the site that is permeable.

Then map the connections. Green infrastructure works as a network, so the plan has to show what the site links to: a river corridor, a park, a local wildlife site, a public right of way, a hedgerow running out into farmland. Barriers matter too, and a road, a fence line or a level change that severs a connection should be shown.

Photographs and a plan do the work here. Keep the ecological baseline separate, because the habitat survey underpinning a Biodiversity Net Gain Assessment has its own method and its own condition assessment, and the two documents should cite each other rather than duplicate.

Typologies proposed and their functions

The heart of the document is a table of what is proposed, by typology, with the function each performs.

Multifunctionality is the point. A swale that attenuates surface water, supports wet grassland and forms the edge of a walking route is doing three jobs on one piece of ground, and saying so explicitly is what distinguishes a green infrastructure plan from a landscape drawing with labels.

Be honest about single function areas too. A strip of mown amenity grass between a footway and a fence performs one function badly, and a reviewer will notice.

Quantifying provision against local standards

This is where the document earns its place. Set out the numbers against whatever standards apply locally.

Common measures include open space provision per dwelling or per head against an adopted standard, accessible natural greenspace within a stated walking distance, canopy cover as a percentage of site area at planting and at maturity, permeable surface as a proportion of the site, and, in London, the urban greening factor score calculated under the London Plan.

Show the calculation as well as the result. A green infrastructure plan that states an urban greening factor score without the table of surface types, areas and factors is asking the reviewer to take it on trust, and a borough officer will ask for the working. The same applies to canopy cover: state the method, the crown diameters assumed and the year the mature figure represents.

Where a standard is not met, say so and explain what is offered instead. Silence on a shortfall reads worse than the shortfall.

Integration with drainage and biodiversity net gain

Three documents describe overlapping ground and they must agree. The drainage strategy sets attenuation volumes and discharge rates. The biodiversity metric records habitat types, areas and conditions. The green infrastructure plan describes the same features as functioning parts of a network.

The failure mode is a swale that appears with one area in the drainage calculation, a different habitat type in the metric, and a third description in the landscape drawing. Fix it by working from a single schedule of areas, owned by one person, that all three documents draw from.

The management implications also have to align. A biodiverse roof counted as habitat in the metric carries a 30 year management commitment under the biodiversity gain condition, and that obligation should appear in the management section here too. Coordination with the Drainage Strategy is worth doing at concept stage, because attenuation features designed late tend to displace planting rather than integrate with it.

Access, routes and the spaces between

Green infrastructure that people cannot reach delivers a fraction of its value. Set out the pedestrian and cycle routes through and to the green spaces, the surfacing and widths, the lighting strategy and where it is deliberately omitted for wildlife reasons, seating and bins, and the arrangements for accessibility including gradients and step-free routes.

Dark corridors are worth a sentence of their own. Where a route runs alongside a hedgerow or watercourse used by bats, an unlit or low level lit route may be the right answer, and the lighting design should be consistent with the guidance the Lighting Assessment applies. Where that conflicts with a perception of safety, say how the conflict has been resolved rather than leaving it.

Canopy cover targets have their own policy history and their own measurement traps, covered in the guidance on canopy cover targets and how policies apply them.

Management, maintenance and funding

Every feature needs an owner, a maintenance regime and a funding route. Set them out in a table: feature, responsible party, frequency of operations, first five years and thereafter, and the funding mechanism, whether a management company service charge, a commuted sum to the authority, or adoption by the highway authority.

Establishment is the phase that fails. Newly planted trees need watering through the first three summers, and a specification that stops at planting produces a thin avenue by year five. Say who waters, how often and for how long.

Where an area is proposed for adoption, check the adopting body will take it. Highway authorities and parks departments both refuse features they consider unmaintainable, and rain gardens in a carriageway edge are a common sticking point.

Monitoring and the reporting schedule

Close with what will be measured and when. A workable schedule names the indicators, the baseline figure, the target, the monitoring method, the frequency and the recipient of the report.

Useful indicators are canopy cover, tree survival rate, habitat condition where it is also counted in the metric, and the completion of planned establishment operations. A monitoring schedule that mirrors the biodiversity gain plan's reporting points avoids duplicated survey visits.

That schedule is also the part most likely to be secured by condition or by a section 106 obligation, so write it as something you are prepared to be held to. A Green Infrastructure Plan drafted with AI assistance can carry the structure, the typology tables and the monitoring framework. The quantities, the local standards and the management commitments have to come from the design team and the client who will fund them.

PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval. This is general guidance, not legal advice; check the position with your local planning authority or a qualified professional before relying on it.