The human version (we wrote this, not the council)This section explains what the Local Plan is and how it was prepared. The Local Plan is the council's main planning document, setting the strategy for homes, jobs and infrastructure in Three Rivers up to 2041. It must follow national planning policy and, once adopted, replaces the Core Strategy (2011), the Development Management Policies document (2013) and the Site Allocations document (2014). Work began in 2017 with several rounds of public consultation, backed by technical studies. The plan comes in two parts: Part I contains planning policies and Part II sets out site allocations.
OpenConsult / Three Rivers Plan Explorer
Flooding & water
Flood risk, drainage, SuDS, river and groundwater quality, and water efficiency.
83 sections of the plan, in document order.
The human version (we wrote this, not the council)This section sets out the site allocations for Abbots Langley and Leavesden. Eleven housing sites are allocated, references H1 to H11, with a combined indicative capacity of around 550 homes. They range from small garage courts of five or six homes to larger sites such as land adjacent to Fraser Crescent and Woodside Road, with 249 homes, and land at Mansion House Equestrian Centre, with 98. Each site table sets out size, phasing, Green Belt status and requirements covering matters such as access, heritage, flooding and trees.
The human version (we wrote this, not the council)This section sets out the site allocations for Bedmond. Three sites are allocated for around 138 homes in total: Church Hill Road (102 homes), 56 High Street (20 homes, with possible commercial space) and North Cott, East Lane (16 homes). All three are classed as grey belt land and remain within the Green Belt. Requirements include access improvements, heritage assessments near listed buildings, surface water flood mitigation and protection of trees covered by Tree Preservation Orders.
The human version (we wrote this, not the council)This policy embeds the national presumption in favour of sustainable development, meaning the council takes a positive approach and works with applicants to approve proposals wherever possible. All development must address a list of sustainability aims. These include cutting carbon emissions to help reach the council's net zero ambition by 2030 for its own emissions and district-wide net zero by 2045, avoiding flood risk, prioritising brownfield land, providing mixed housing including affordable homes, supporting town and village centres, locating development to reduce travel, delivering infrastructure, good design and managing pollution.
The human version (we wrote this, not the council)This section sets out the site allocations for Carpenders Park. Three housing sites are allocated with a combined indicative capacity of around 244 homes: Land at Oxhey Lane (98 homes), Land North of Oxhey Lane (96 homes) and Grange Wood (50 homes). The site tables set out size, phasing and Green Belt status, together with site-specific requirements and constraints that future planning applications must address.
The human version (we wrote this, not the council)This policy sets housing density expectations. New housing should normally be built at 50 dwellings per hectare within the developable area of a site, with higher densities expected in places well served by public transport, services and facilities. Lower densities may be acceptable in special cases, such as areas of historic or landscape value or specialist housing, but must be justified with supporting evidence. Density should generally be lower at the edges of a site and increase towards its centre.
The human version (we wrote this, not the council)This section sets out the site allocations for Croxley Green. Five housing sites are allocated with a combined indicative capacity of around 300 homes. The largest are Land at Croxley Station on Watford Road (163 homes) and Cinnamond House (80 homes), alongside smaller sites at garages off Grove Crescent (19), Land at Barton Way (8) and Land South of Scots Hill (30). Each site table lists size, phasing, whether land is greenfield or brownfield, Green Belt status and detailed requirements for future applications.
The human version (we wrote this, not the council)This section introduces the employment and economy chapter. The local economy relies on professional services, construction, retail and hospitality, with a notably strong film and TV sector at Warner Bros. Studios in Leavesden and many knowledge-based businesses. Many residents commute out of the district, though this has fallen since Covid. Demand for office space has declined, and the 2024 economic study finds the district has broadly the right amount for the next 15 years, but low vacancy rates mean existing offices should be protected while industrial and warehouse demand stays strong.
The human version (we wrote this, not the council)This section sets out the site allocations for Garston. One site is allocated: Land North of Bucknalls Lane, a 5.8 hectare site for housing and employment with an indicative capacity of 144 homes. The northern part of the site is to be used for employment. The land was removed from the Green Belt during the plan process. The site table also sets out phasing and the constraints, such as buffers and flood mitigation, that any future application must address.
The human version (we wrote this, not the council)This section sets out the site allocations for Hunton Bridge. A single housing site is allocated: Land at Mill Place, with an indicative capacity of 10 homes. The site table records its size, phasing and Green Belt status, together with the site-specific requirements and constraints, including access, heritage and flood risk matters, that future proposals must take into account.
The human version (we wrote this, not the council)This section sets out the site allocations for Kings Langley. Four housing sites are allocated with a combined indicative capacity of around 520 homes. The largest is West of the Kings Langley Estate at 400 homes, followed by land adjacent to the RES site at Egg Farm Lane with 100. Two small sites, Flower House on Station Road and Lonsdale on Hyde Lane, provide 10 homes each. The site tables set out size, phasing, Green Belt status and requirements covering matters such as access, heritage, flooding and biodiversity.
The human version (we wrote this, not the council)This section sets out the site allocations for Maple Cross. Three sites are allocated with a combined indicative capacity of around 1,635 homes. Most come from one strategic site, Land to the West and South of Maple Cross, allocated for up to 1,500 homes plus supporting uses including a primary school, community, retail and commercial space; this land was removed from the Green Belt. The other sites are Land to the North of Chalfont Road (130 homes) and garages behind Longcroft Road (5 homes).
The human version (we wrote this, not the council)This policy requires all development to be designed and built to cope with a changing climate. Non-residential schemes over 1,000 square metres should achieve BREEAM Excellent certification, an independent sustainability standard, including full water efficiency credits. Buildings must follow a cooling hierarchy that favours passive measures such as orientation, shading and natural ventilation before mechanical cooling. Major residential schemes must complete a CIBSE TM59 overheating assessment and major non-residential schemes a TM52 assessment. Development must also build in resilience to extreme weather, use sustainable drainage and reduce the urban heat island effect.
The human version (we wrote this, not the council)This section sets out the site allocations for Mill End. Four sites are allocated with a combined indicative capacity of around 548 homes. The main site is Land to the South of Shepherds Lane and East of the M25, a 20.8 hectare grey belt site for 520 homes plus supporting uses including gypsy and traveller pitches, a medical centre or GP surgery, extra care housing and public open space. The remaining sites are small: garages behind Drillyard on West Way (6 homes), Quickwood Close garages (16) and garden land off Uxbridge Road (6).
The human version (we wrote this, not the council)This section sets out the site allocations for Oxhey Hall. Two housing sites are allocated with a combined indicative capacity of around 108 homes: Vivian Gardens (8 homes) and Land at Hampermill Lane (100 homes). The site tables set out size, phasing and Green Belt status, along with the site-specific requirements and constraints that future planning applications must address.
The human version (we wrote this, not the council)This section introduces the biodiversity, green and blue infrastructure and landscapes chapter. It explains that England is one of the most nature-depleted countries on Earth and Three Rivers has not escaped that decline. New laws, especially the Environment Act 2021, give councils a duty to conserve and enhance biodiversity, and introduce Biodiversity Net Gain and Local Nature Recovery Strategies. Development must follow the mitigation hierarchy: avoid harm first, then mitigate it, and only compensate as a last resort. The district's wildlife, from wetlands to woodlands, is described as integral to its character and quality of life.
The human version (we wrote this, not the council)This section sets out the site allocations for Rickmansworth. Six sites are allocated: four housing sites providing around 151 homes, including the Affinity Water Depot on Church Street (75 homes) and a depot at Stockers Farm Road (40 homes), plus two care home sites. Land on London Road is allocated for a 75-bedroom care home, counted as equivalent to 40 dwellings, and Meresworth for a 51-bed care home, equivalent to 27 dwellings. Site tables list size, phasing, Green Belt status and site-specific requirements.
The human version (we wrote this, not the council)This policy requires qualifying development to deliver at least 10% measurable biodiversity net gain, meaning the site must be left better for nature than before, measured with the Government's statutory metric. Gains should be delivered on site first, then off site, with buying statutory credits a last resort, secured by monitoring plans lasting at least 30 years. Protection of wildlife sites is weighted by importance, from international down to local, and loss of irreplaceable habitats such as ancient woodland will normally be refused. New housing must provide on average at least one swift brick per dwelling for nesting birds.
The human version (we wrote this, not the council)This section sets out the site allocations for Sarratt. One housing site is allocated: Adams Nurseries on Church Lane, with an indicative capacity of 15 homes. The site is classed as grey belt and remains in the Green Belt, and development should be limited to the brownfield part of the site, with amenity space and biodiversity net gain on the greenfield areas. The site table also covers access constraints and other requirements for future proposals.
The human version (we wrote this, not the council)This section sets out the site allocations for South Oxhey. Four housing sites are allocated with a combined indicative capacity of around 200 homes: Northwick Day Centre on Northwick Road (50 homes), the former Sir James Altham School (30), Pinewood Lodge (40) and Land South of St Josephs (80). Each site table sets out size, phasing, whether the land is brownfield or greenfield, Green Belt status and the site-specific requirements future proposals must meet.
The human version (we wrote this, not the council)This policy protects the Chilterns Beechwoods Special Area of Conservation, an internationally important wildlife site, from pressure caused by new residents visiting it. Development within the site's zone of influence that would add 100 or more homes must undergo a Habitats Regulations Assessment. Where required, schemes must provide mitigation or avoidance measures, principally Suitable Alternative Natural Greenspace (SANG), attractive green space designed to draw visitors away from the protected area, or a financial contribution towards it. The 100-home threshold was set on the advice of Natural England.
The human version (we wrote this, not the council)This policy manages flood risk and water use. Development in flood risk areas must pass national tests that steer building to the safest available land, and no new development is allowed in Flood Zone 3b, the functional floodplain. Floor levels in Flood Zones 2 and 3 must sit at least 300mm above predicted maximum flood levels, and major schemes need sustainable drainage limiting runoff to greenfield rates. Buildings must stay 10 metres from main rivers and 5 metres from other watercourses. As the district is seriously water stressed, new homes must use no more than 110 litres per person per day.
The human version (we wrote this, not the council)This section introduces the environment chapter. The district takes its name from the Rivers Colne, Chess and Gade, which meet at Rickmansworth, and with the Grand Union Canal and many former quarry lakes the area has a complex flooding picture and a wide floodplain. Three Rivers faces flood risk from rivers, surface water, groundwater, sewers and reservoirs, and climate change is expected to increase that risk. At the same time the district lies in one of the driest parts of the UK, so development must be flood-safe and use water efficiently.
The human version (we wrote this, not the council)This policy prevents development that would cause, or be harmed by, unacceptable pollution, covering land contamination, air, water, noise, vibration, light, odour and land instability. Building on or near former landfill or suspected contaminated land is only allowed where there is no threat to future users or to groundwater. Development must not worsen air quality, particularly in the district's two Air Quality Management Areas near the M25 at Chorleywood. Noise-generating and noise-sensitive uses must be kept apart or mitigated, and external lighting must be the minimum needed, avoiding harm to neighbours, wildlife and the countryside.
The human version (we wrote this, not the council)This section sets out the employment site allocations. Evidence in the South West Herts Economic Study (2024) found no need for new office sites, and recommends resisting any loss of office space. Four existing employment areas are safeguarded: Croxley Business Park (E1), Tolpits Lane (E2), Maple Cross/Maple Lodge (E3) and Kings Langley Employment Area (E4). Two small extensions to Croxley Business Park are allocated as E5 and E6, and Leavesden Park (E7) is allocated as an employment site, protected by an Article 4 Direction that stops offices changing to homes without planning permission.