As at 20 September 2026
See why the leftover sites do not add up
This map starts with every leftover site the East of England still lists — 2,969 of them, 122,616 homes-worth on paper — and then takes away, one reason at a time, the sites that cannot take the houses. Each site is counted out once, at the first reason that stops it. By the last step 20,610 homes-worth are still standing on 668 sites, against a regional target of about 1.3 million homes over thirty years.
The starting total is this site's own extract of the government's leftover-land file. CPRE's compiled 2024 figure for the East is 132,338 — about 9,722 higher, because CPRE worked from a single 2024 snapshot and councils have updated their registers since. Both numbers are published on the numbers, and the method behind every colour is on how we counted.
- Still standing
- Taken out at this step
- Taken out earlier
- This step’s example
Step 1 of 11
The whole list
Start with every leftover site the 45 East of England councils still list. This is the pile people mean when they say the houses can go here. CPRE's compiled 2024 figure for the region is 132,338 homes-worth; the live government file behind this map runs a little under that, because councils update their registers at different speeds. Either way, nothing has been taken off it yet. From here each step removes the sites stopped by one reason, and counts a site only once, at the first reason that stops it. Watch the number on the right come down.
No permission
First, keep only the sites that have actually been granted planning permission. Everything else is a council's judgement that homes could go there one day, not a consent anyone can build on. Bourn Airfield is the scale of what drops out: 3,500 homes-worth on the register with no permission recorded at the date of this extract. And permission is a low bar — CPRE's national work found sites under construction or finished came to about 2% of listed capacity. Everything after this step is happening to land that has already cleared the planning test.
Example: Bourn Airfield New Village, South Cambridgeshire · 3,500 homes · 171.8 ha · South Cambridgeshire
Sources: State of Brownfield 2025; Town and Country Planning (Brownfield Land Register) Regulations 2017
They flood
Now take out the permissioned sites in the places where most of the low ground is Flood Zone 3: the Fens, the Broads, and the Essex and Thames estuary coast. Fenland's own flood study puts about 67% of that district in Zone 3. Purfleet Centre is 2,850 homes-worth with consent on the Thames floodplain. Zone 3b is not available for new homes at all; Zone 3a needs the sequential and exception tests, raised floor levels and safe access, and the flood storage eats the plot before the houses are drawn. This is the one screen on the map still drawn at authority level — the Environment Agency's flood zone file is far too large to intersect here — so read this colour as a region, not as a survey of each plot.
Example: Purfleet Centre, Thurrock · 2,850 homes · 56.9 ha · Thurrock
Sources: Fenland Level 1 Strategic Flood Risk Assessment; Flood Map for Planning (Flood Zones 2 and 3); National Planning Policy Framework (December 2024 revision)
The nutrient freeze
Next, the sites inside a nutrient neutrality catchment — the Broads, the Wensum, and the Stour and Orwell. These points are tested against Natural England's published catchment boundaries rather than their council's name, so this is a site-level colour. Since March 2022 a council cannot consent overnight accommodation inside them without demonstrating nutrient neutrality first. Deal Ground in Norwich holds consent for 580 homes and has sat in that freeze. This is also the step most likely to change: on 17 September 2026 Natural England published a draft Environmental Delivery Plan for the Broads and Wensum, offering developers a flat £2,675 a home in place of finding their own mitigation, and stating it would support up to 15,780 homes. It is a consultation draft, not yet in force, and a levy is a cost rather than a cancellation — but if it is made, some of this colour comes back.
Example: Deal Ground, Bracondale, Norwich · 580 homes · 16.2 ha · Norwich
Sources: Nutrient neutrality advice to competent authorities; Nutrient neutrality catchment dataset; Nutrient pollution: draft Norfolk Environmental Delivery Plan consultation; Understanding the Nature Restoration Fund
Ground to clean
Then the sites carrying a hazardous substances entry on the register, or a former use that leaves ground to clean: gasworks, tips, tanneries, foundries, filling stations, scrapyards. Mill Road Depot in Cambridge is 236 homes-worth on a working council depot. Demolition, asbestos, ground gas and buried tanks all get priced before the first house is sold, and the HCA's 2015 guidance is still the official handbook for what that costs. The register's hazardous field is thinly filled, so this step reads the site's name and notes as well — which means it is a proxy. Treat a blank as unknown, not as clean.
Example: Mill Road Depot, Cambridge · 236 homes · 2.2 ha · Cambridge
Sources: Guidance on dereliction, demolition and remediation costs; Banking on Brownfield
Someone has to pay
Nothing leaves the count at this step. It is here because the last three screens all end in the same place: a bill. Flood works, remediation and nutrient credits do not evaporate. They come off what the land is worth, or they go onto the price of the house, or the scheme simply never happens. Where sale values are high — Cambridge, west Hertfordshire — the bill is payable, and the buyer pays it. Where they are low, the same bill closes the site: North Quay in Great Yarmouth is 160 homes-worth stacking a weak market, a floodplain and a waterfront to repair. The lit points here are the lower-value coastal and Fenland authorities. Leftover land is not a cheap-homes policy. It is the most expensive land to build on, and the places holding the most of it can least afford to.
Example: North Quay, Great Yarmouth · 160 homes · 3.5 ha · Great Yarmouth
Sources: Guidance on dereliction, demolition and remediation costs; Banking on Brownfield
Nobody can sign
Now the sites whose owner the register cannot pin down: mixed ownership, unknown ownership, or the column left blank. After permission, this is the largest cut on the walk. Napier Park in Luton is 1,268 homes-worth with consent and mixed ownership on the file. A ransom strip, a leaseholder who will not move, a statutory undertaker with no housing mandate, or four owners of a row of lock-ups will each hold a site for years. Compulsory purchase exists, on a cost and a timetable that suit a town centre scheme and not a third of a hectare. Some of these do get assembled in the end — this is a flag on the paperwork, not a death certificate — but a list of land is not a list of willing sellers.
Example: Napier Park, Kimpton Road, Luton · 1,268 homes · 24.4 ha · Luton
Sources: Brownfield land registers data standard; Banking on Brownfield
Still Green Belt
These points are tested one at a time against the government's Green Belt polygons, and the honest answer is much smaller than the slogan. Nearly all of this region's leftover land sits inside towns, and the towns of Hertfordshire and west Essex are inset — cut out of the Green Belt that wraps around them. An earlier version of this map tagged every site in a Green Belt authority and made this look like one of the big constraints. It is not, and the correction belongs on the page rather than in a footnote. What the real boundary catches is the genuine edge case: the Oddysey Health Club at Knebworth, 86 homes-worth of previously developed land actually inside the line. Previously developed is not a Green Belt exemption. It is just a much rarer problem for brownfield than for the fields next door.
Example: Oddysey Health Club, Knebworth · 86 homes · 4 ha · North Hertfordshire
Sources: Green belt dataset; National Planning Policy Framework (December 2024 revision)
No room for nature
Then the plots too tight to carry biodiversity net gain: larger than 0.2 hectares, smaller than half a hectare. 64-68 Newmarket Road in Cambridge is 80 homes-worth on 0.49 hectares. Once access, parking, bins, a turning head and drainage are on the plan, there is no corner left for habitat that has to be maintained for thirty years — so the gain is bought off-site, or the number of homes comes down. The lower edge of that band is not arbitrary. From 6 August 2026 the government exempted sites of 0.2 hectares or less from net gain altogether, expecting it to lift the duty from about half of residential permissions, which is as close as policy comes to conceding that the smallest leftover plots cannot carry it. Those exempt sites stay in the count here. There are a great many of them, and they average single figures of homes each.
Example: 64-68 Newmarket Road, Cambridge · 80 homes · 0.5 ha · Cambridge
Sources: Biodiversity Gain (Town and Country Planning) (Amendments and Transitional Provisions) (England) Regulations 2026; Improving the implementation of biodiversity net gain for minor, medium and brownfield development: government response; Planning Practice Guidance: biodiversity net gain; Environment Act 2021, Part 6 (nature and biodiversity)
Still needed for jobs
Last, the sites still doing a job: depots, docks, rail sidings, freight yards, occupied industrial estates. Brooke Business Park in Lowestoft is 850 homes-worth on the register and a working business park on the ground. Under the 2017 regulations a site can be suitable, available and achievable for housing and still be the wrong place to put houses, because a region cannot meet its housing need out of the register and keep an employment land supply on the same hectares. Counting both is counting the land twice. This is a keyword screen over site names and notes, so it is the roughest step on the walk — a proper employment land review is the local test.
Example: Brooke Business Park, Lowestoft · 850 homes · 11.9 ha · East Suffolk
Sources: Banking on Brownfield; Town and Country Planning (Brownfield Land Register) Regulations 2017
What is left
This is what survives every screen: permissioned, dry, outside a nutrient catchment, no recorded ground to clean, one identifiable owner, outside the Green Belt, big enough to hold its nature, and not already in use. These places are real and some of them are excellent. Land at Riverwell, beside Watford General, is 1,383 homes-worth of exactly the brownfield regeneration that does get built, and CPRE separately notes Peterborough as an authority whose permissioned leftover land could cover its own five-year target. The argument was never that leftover land delivers nothing. It is the size of what is left, set against roughly 1.3 million homes over thirty years: a few months of the East's official target rather than an alternative to building anywhere else. And this is still the generous reading, because every site on this last screen is a row on a register until somebody builds it.
Example: Land at Riverwell and Watford General Hospital · 1,383 homes · 18.1 ha · Watford
Sources: Brownfield land dataset; Planning Practice Guidance: housing and economic needs assessment
What this map is not: a survey. Registers publish a point, not a boundary, so no colour here is a site inspection. Green Belt and nutrient neutrality are tested against the published polygons for those layers, one point at a time. Flood risk and local market weakness are tagged at authority level, because the Environment Agency's flood zone file is too large to intersect here. Contamination and employment use are read partly from a site's name and notes, which is a proxy and will be wrong in both directions. For a named plot, go to the council's own register entry and the Environment Agency flood map.