2022 susdrain SuDS Awards entries overview
Submitted by:
Atkins, United Utilities, Landscape Engineering, Horticon
Elliott Wood Partnership Limited x3
Meristem Design and London Borough of Waltham Forest
Southend City Council, Mott MacDonald
Submitted by:
Scheme location:
Leeds Skelton Lake Services M1 J45, Leeds, West Yorkshire
Summary:
A ‘new concept’ building design was commissioned by the site developers and owners Extra MSA Group for the new Leeds Skelton Lake Services building at Junction 45 on the M1, located adjacent to Skelton Lake, a 40,000m2 area of ecologically diverse country park, 2 miles southeast of Leeds city centre. To minimise the visual impact of the development the main 5,277m2 amenity building features an over sailing, undulating green roof. The roof is configured in a unique ‘ribbon’ pattern in eleven separate sections. Designed as part of the development’s ‘landscape mitigation and green space strategy’, the living roof and timber eaves closely echo the nearby woodland and lakeside habitat and blends in with the country park backdrop
SuDS features:
- Wildflower green roof
- Tree pits
- Detention basin
Award category:
New commercial development (any scale)
Submitted by:
ABG Geosynthetics Ltd
Scheme location:
Middlewood Locks, Manchester
Summary:
Located at the first locks of the Manchester, Bolton & Bury Canal, the second phase of the £1bn Middlewood Locks mixed-use scheme delivers 546 apartments across 4 new buildings with private podium gardens. Phase 2 of the project (where the blue roof attenuation system is installed) regenerates an area of 6 hectares of brownfield land in Salford. The site discharges to the renovated balancing basins that service the adjacent canals and the River Irwell.
The extensive soft landscaping and permeable resin bound paving reduces the impact of surface water run-off to less than that of the pre-developed brownfield land.
SuDS features:
- Blue roof water attenuation system
Tree pits:
- Sedum roof
- Permeable resin bound surfacing
Award category:
New housing development – large (more than ten units)
Submitted by:
Scheme location:
Cardiff Centre for Student Life
Summary:
The Centre for Student Life (CSL) project consists of a new flagship building for Cardiff University and surrounding Park Place public realm improvement works in the centre of Cardiff, with construction works completed in 2022. Arup’s multidisciplinary scope included the Civils and Drainage design, with IBI acting as Landscape Architect. Due to significant constraints within the highway area limiting source control solutions, the team designed a large ‘end of catchment’ rain garden system, including a sediment forebay and below ground storage system which maximise water quantity and quality benefits. The large rain garden (believed to be the largest in Cardiff city centre)
Is prominently visible for pedestrians to obse rve the SuDS feature controlling runoff whilst improving the parks amenity and biodiversity. The SuDS system was designed reduced the outflow into the existing sewer to the greenfield runoff rate , reducing the likelihood of downstream city centre flooding and the risk of overwhelming the sewer during large storm events. The scheme was one of the first schemes to achieve full SAB approval in Cardiff.
SuDS features
- Sediment Forebay
- Rain garden
- Attenuation cells
Award category:
Regeneration and retrofit – small scale (less than one hectare)
Submitted by:
Scheme location:
The Bee House, 140 Milton Park, Park Drive, Abingdon, OX14 4SB
Summary:
Located on Milton Park an existing building and landscape was re-purposed to create a new collaborative work space, lettable offices and café at ‘The Bee House’. Former carpark to the building entrance was replaced with a series of bioretention planters creating seating opportunities for occupiers and café users. Water has been diverted from parts of the roof and hard landscaping areas into the bioretention planters, slowing and cleaning the water before it discharges into an adjoining water course, which has also been enhanced with native marginal planting. A thick gravel mulch layer at the top of the bioretention planters helps to retain moisture whilst reducing the need for weeding and creates an attractive backdrop for the planting. This was designed as a test-bed for moving the design of landscapes on the science park at Milton Park forward. Located at the front of MEPC’s new headquarters and flagship building, the bioretention planters had to look good all year round, whilst providing all of the benefits of a SuDS scheme.
SuDS features:
- A series of Bioretention Planters with gravel mulch and trees
- Discharging to existing stream/ditch which has been enhanced through dredging and additional planting.
Award category:
Regeneration and retrofit – small scale (less than one hectare)
Submitted by:
Atkins, United Utilities, Landscape Engineering, Horticon
Scheme location:
Suds for Schools Programme (8 Schools), North-West
Summary:
The schemes focus on the retrofit of eight schools within the North-West to integrate SuDS solutions into the school sites to provide multiple-benefits to the schools, community, and water company. Each school was identified based on local sewer flooding issues, additionally those connected into the existing combined sewer networks were prioritised. The majority of schemes reconnect back onto the existing networks via overflow connections, with reductions in peak flow through attenuation and removal of catchment area through infiltration-based techniques. Innovative SuDS solutions were created due to the manner of the sites in which these solutions were installed i.e., schools. The types of innovative SuDS include a rainbow arched walkway, permeable path conduits (conveying roof area into a swale whilst infiltrating).
SuDS features:
- Swales
- Pond
- Raingardens
- Bioretention planters
- Tree pits
- Infiltration basin
- Permeable surfacing / gravel paths
- Water butts
- Filter drains
Award category:
Regeneration and retrofit – large scale (more than one hectare)
Submitted by:
Scheme location:
Outside India Building, 33 Water St, Liverpool L2 0RD – The Strand Street
Summary:
The Strand is at the epicentre of Liverpool’s renowned waterfront, surrounded by Grade II listed buildings including the Liver Building, part of the iconic ‘Three Graces.’ This revamp of The Strand reclaims large areas for people rather than vehicles and is environmentally conscious in all respects of its design and execution.
The regeneration scheme exemplifies the very best of green infrastructure projects, providing a new sustainable urban drainage system with on-going data analysis for storm waterflow, water filtration and air quality by Liverpool University, keeping us connected via safer walkways, new pedestrian squares, segregated cycle lanes and introducing large canopies of trees and celebrating the city’s heritage.
One of the most critical impacts on human society and the global environment is aggressive urbanisation, which continues to increase in scope and scale. Cities have become a point of intersection of problems characterized by complexity and uncertainty. Nature Based Solutions are a unifying concept that can support transition to healthy, inclusive and sustainable communities in urban environments and that can help build resilience and climate adaptation. The City of Liverpool is tackling these issues through “Nature Based Solutions” to deliver a wide range of Innovative environmental improvements.
The project contributes to the mitigation of climate change risks, increases the resilience to climate change effects, improves health and well-being and improves air quality and biodiversity.
SuDS features:
- Tree pit filtration & attenuation
- Permeable paving
Award category:
Regeneration and retrofit – large scale (more than one hectare)
Submitted by:
BCA Landscape Ltd
Scheme location:
Northbank Green - Wirral Waters UK CH41 1DR
Summary:
We are thrilled to reveal this ground-breaking new NET Climate-Positive neighbourhood park on Wirral Waters, inspired by the fascinating history of the area and the latest thinking on sustainable ‘nature based’ design solutions.
- Utilising integrated ‘nature based’ design solutions to help society adapt to climate change, reduce flood risk whilst simultaneously enhancing the environment.
- A whole new ‘green’ site ecology created from a derelict contaminated site – with 90 new trees and 1000’s of new plants, including a wide range of native species.
- Creating a site-specific unique design narrative and aesthetic inspired by the location and its rich industrial history.
- Up-cycling of materials from the dockland site, creating a rich material palette and saving on raw materials and avoiding unnecessary waste.
The creation of a landscape led ‘nature based’ sustainable urban drainage system [SUDS], including planted swales + bio-retention planting beds that are fully integrated into the park design.
All water landing on the site is directed into these SUDS beds, helping to water the new planting systems, rather than washing away direct in to drains [as in traditional grey water systems]. Any excess water is then filtered through a natural sand/soil filter medium and gravel beds. This helps cleanse the water and remove pollutants and also slows and mediates storm flow conditions, creating a reduced low-speed minimal water flow into the docks, avoiding the usual storm peaks that can often flood adjacent sewers and streets.
The regeneration scheme exemplifies the very best of green infrastructure projects, providing a new sustainable urban drainage system
SuDS features:
- Tree pit filtration & attenuation
- Permeable paving
- Swales
- Bio-retention Beds
- Drought tolerant planting
Award category:
Regeneration and retrofit – small scale (less than one hectare)
Submitted by:
Scheme location:
West Norwood Cemetery and Crematorium, London
Summary:
The site is a 185 year old cemetery and one of the original “Magnificent Seven” cemeteries of London. It is a site of major historic and architectural interest and an English Heritage ‘Registered Landscape’ on the ‘Heritage at Risk Register’ and Conservation Area with more than 60 listed monuments and structures. There are over 42,000 graves across the site and around 200,000 interments. The site is steeply sloping with over 20m of fall across the land.
Design provides permeable sub-base and check-dam arrangements to manage surface water from the paths and surrounding catchments before discharging into the culverted watercourse at the northern end of the site (via existing connections where possible). The formation of the check-dams was developed to consider the formation of the depth of excavation required in a heavily constrained site.
Given proximity to very old graves (as well as the requirement to keep the space open to visitors and mourners attending the crematorium throughout construction) the check-dam, sub-base arrangement allowed works to be self-contained between each check-dam, eliminating the need for wider or deeper excavations which could have potentially affected graved or undermined listed monuments and structures.
SuDS features:
- Permeable sub-base
- filter strips
- attenuation crates
Award category:
Regeneration and retrofit – large scale (more than 1Ha)
Submitted by:
Elliott Wood Partnership Limited
Scheme location:
Guildford Crematorium. New Pond Rd, Godalming GU7 3DB.
Summary:
The development included the demolition of the existing crematorium building, which was replaced with a new spectacular chapel, floral tribute and book of remembrance structure. The works also included extensive landscaping proposals which unlocked the biodiversity and amenity value of the development, creating a tranquil space for visitors during what is inevitably a tough period in their lives.
The site was relatively large (6Ha), with a shallow outfall connection to an existing watercourse at the southern boundary.
The site was a fully functioning crematorium pre-development, which was kept operational throughout construction. Phasing was therefore a key consideration throughout the design and construction process.
There were constraints above and beyond that of a typical development, for example, areas of ‘no-dig’ were identified across the site due to the presence of interred and scattered ashes.
A variety of SuDS devices were incorporated into what was a landscape driven scheme, which provided betterment to peak surface water run-off rates, improved water quality, increased biodiversity, enhanced amenity and maintained a shallow-depth method of conveyance across the site.
The proposed SuDS strategy was ultimately designed to be sympathetic and supportive to the nature of the development whilst meeting aspirations of the Lead Local Flood Authority.
SuDS features:
- Swales
- Permeable Paving
- Filter Drains
- Filter Strip
- Raingardens
- Geocellular Attenuation
Award category:
New commercial development (any scale)
Submitted by:
Elliott Wood Partnership Limited
Scheme location:
Tower Hamlets Town Hall, Whitechapel Road, E1 1FR
Summary:
A circa £100m re-development of the Grade II former Royal London Hospital into a new Civic Centre for the London Borough of Tower Hamlets (LBTH).
The development will look to consolidate LBTH’s staff members into one central location, providing 1,700 contemporary flexible workspaces plus a range of meeting rooms and welfare facilities for council staff and other partners, anchoring the wider regeneration of Whitechapel.
The existing and proposed buildings occupy approximately 75% of the site area.
The redevelopment had to overcome many challenges, including:
- Grade II listed building
- Historic demolition
- Buried archaeology
- Shallow London Underground tunnels
- Buried substation
- Root protection areas
- Central, building-centric urban location
Historic demolition down to the former basement level at the rear of the site had left a low-lying area under where the new-build wrap around extension would be constructed. No basement was required in this area. Instead of importing fill, we identified this as an opportunity for locating the attenuation tank. This solution saved excavation that would have otherwise been required to bury the approx. 510m3 attenuation tank and saved the import of the same volume of material that would have otherwise been required under the building.
Site discharges to a 450mm diameter Thames Water combined sewer in Whitechapel Road
SuDS features:
- Living roofs
- Attenuation tank
Award category:
Regeneration and retrofit – large scale (more than one hectare)
Submitted by:
Elliott Wood Partnership Limited
Scheme location:
Wendon, Mersey Street, Borth Y Gest, Porthmadog, LL49 9UF
Summary:
Situated high up on the cliffs overlooking the river Dwyryd, in the coastal rural village of Borth-y-Gest, is a dwelling called Wendon.
Wendon is an existing dwelling that holds sentimental value to the client, having spent many happy holidays there during their childhood. After years of unoccupancy, the existing house had fallen into an unsafe state. After purchase by the clients, the design team were commissioned to design a replacement contemporary family home where habitation is futureproofed for subsequent years and generations.
Being sited on a cliff, the geology is weathered; fractured bedrock is overlain with limited superficial deposits. As a result, soil infiltration rates were patchy depending on the depth of superficial deposits and the integrity of the underlying bedrock, whilst the existing dwelling discharged both foul and surface water to the combined sewer in Mersey Street. We undertook site investigation to find a location that would maximise the chance of infiltration based on the underlying geology to enable us to locate the raingarden. As a precaution, an overflow to a combined sewer is provided which would discharge, if required, at a peak discharge rate of 1 l/s.
SuDS features:
- Permeable paving
- Tree pit
- Raingarden
- Living Roof
- Filter strips
Award category:
New housing development – small (one to ten units)
Submitted by:
Scheme location:
The Bloc, 17 Marble Street, Manchester M2 3AW
Summary:
The project is a proof of concept to show that both A/ Smart attenuation tanks work and that they can significantly reduce discharge & B/ that you can retrofit a blue roof onto an existing roof despite it being ‘weak’ or having slight falls.
The principle of the smart tank is to combine the rainwater harvesting tank into the attenuation tank. The smart tank it keeps as much water for rainwater harvesting (more than a traditional harvesting system) and make decisions when to discharge based on the incoming weather.
The roof discharges to the UU sewer, but importantly, when it does discharge its discharges AHEAD of the storm when the sewer is empty. It holds water and doesn’t discharge during the storm event when the sewer is at capacity.
SuDS features:
- Attenuation
- Blue roof
- Green roof
- Passive irrigation
- Rainwater harvesting
- Smart attenuation/rainwater Harvesting
Award category:
Regeneration and retrofit – small scale (less than one hectare)
Submitted by:
Scheme location:
HP22 5XF
Summary:
The SUDs scheme was incorporated as part of the development of 149 houses. It included landscaping and some wildflower planting. The swale is not particularly special, it discharges into a watercourse that borders the estate. It has the potential to become a far greater environmental feature. Residents have already added bulbs and sown wildflowers to improve the scheme. We are aiming to reduce mowing and further encourage wild flora and fauna. The area, which is beside a public footpath, has become a destination for residents and others, to enjoy.
SuDS features:
- Swale
Award category:
Community SuDS
Submitted by:
Scheme location:
Garrard Avenue Margate SuDS Scheme
Summary:
The works are located to the south of George V Avenue, upstream of the Key Flood Risk Area of Canterbury Road. Under pre-development conditions, any runoff generated along Maynard Ave and Garrard Ave, when not intercepted by road gullies, generates north flowing exceedance flows that reach the critical parts of George V Avenue and ultimately Canterbury Road/All Saints’ Ave.
An initial review by WSP of the site drainage area identified gullies with excessive contributing catchments. Out of the existing 12 gullies, all of these were found to have catchment areas over 450m2 each, with 6 of these having catchments equal or greater than 700m2 – well above their hydraulic capacity. It is estimated that the pre-development drainage system along Maynard Ave and Garrrad Ave is only capable of draining rainfall events up to the 5 year return period at most, which can be considered a low figure when most of the new schemes are designed for return periods in the range of 30 to 100 years – with an additional allowance for climate change.
SuDS features:
- Tree Pits
Award category:
Regeneration and retrofit – small scale (less than one hectare)
Submitted by:
Scheme location:
Wood Lane, Southmoor
Summary:
Springfield Meadows is a project of 25 zero-carbon homes located in Southmoor, Oxfordshire. Benefitting from diverse shared outdoor spaces and private gardens, it consists of 9 affordable and 16 private houses. They are all beautiful, high-performance homes, which provide comfortable, low-carbon living, thanks to the use of our Biond Building System.
Our client brief was to make this the most sustainable housing development in in the country by achieving zero-carbon footprint & net-zero energy in use for both the private and the affordable houses.
We think Springfield Meadows is the most sustainable development in the country
SuDS features:
- Road base (Type 3 granular)
- Drainage ditches (Type 3 granular)
- Gabions surround ½ of the site where the ground level has been raised to assist with drainage
- Soakaways
- Wildlife pond
Award category:
New housing development – large (more than ten units)
Submitted by:
Scheme location:
The Knowle Arena, Station Road, Sidmouth, Devon
Summary:
Sidmouth flood alleviation scheme, also referred to as Sidmouth Amphitheatre protects 64 properties from surface water flooding, by intercepting flows on Station Road and re-directing them into the adjacent parkland referred to as ‘The Knowle’. Flows are captured on Station Road via two large Crossdrains. Water is then conveyed into the park via a 500mm diameter pipe, before discharging into sediment trap and check dam to slow flows. Runoff then weirs over the check dam and flows along a 90m long swale, before spreading out across the base of the amphitheatre and infiltrating via the spiral shaped filter drain, underlying drainage blanket and geocellular crates. Runoff is then infiltrated when groundwater is low enough or attenuated in the crates (up to 30yr) and onto the base of the amphitheatre (100yr). Attenuated flows are throttled down to 40l/s max from the incoming 275l/s and discharged to the nearby South West Water surface water sewer.
The parkland in which the project was constructed has historically hosted Sidmouth’s International Folk Festival, and so providing a solution that not only protected the town from flooding, but also provided a dual use function as a performance space (the amphitheatre) was essential.
SuDS features:
- Swale
- Check dams
- Spiral filter drain
- Drainage blanket(s)
- Sub-surface geo-cellular crates infiltration tanks
- Detention basin
Award category:
Regeneration and retrofit – small scale (less than one hectare)
Submitted by:
Scheme location:
Kinross Park and Ride, Kinross, Scotland
Summary:
The project transformed a failed car park drainage feature where muddy pools of oily water lingered in the car parking spaces, along a central grass-topped soakaway strip. The soakaway had been designed to accept runoff from the positively drained car park surfaces either side (the soils are free-draining sandy gravel). An original perimeter fence protecting the soakaway had been repeatedly broken. It had eventually been removed by the council, allowing vehicles to drive across, compacting it and tracking mud across the car park.
By excavating the grass, to create a freeboard for entry of runoff, and replacing it with wildflower meadow features, effective drainage functionality was restored, and a biodiverse public amenity created. A central barrier fence deters vehicles from driving across and facilitates maintenance.
Two raingardens were created: a wildflower seedbed enhanced with plug plants (all native species), and a wildflower turf. The third (narrower) centre strip was excavated by the council and filled with large rocks to deter vehicles.
The Park & Ride is a point of entry for visitors to Kinross and is the head of a string of features which comprise the Kinross Raingardens Trail.
Award category:
Regeneration and retrofit – small scale (less than one hectare)
Submitted by:
Kinross-shire Civic Trust
Scheme location:
The former little county of Kinross-shire, central Scotland
Summary:
This community based project began by recognising several good SuDS features which could provide a basis for raising awareness of the scope for multi-benefit landscape features, at all levels from individual properties to housing and industrial estates. In 2019 the idea of achieving 20 raingardens in the district in 2020 was launched & achieved in 2021.
The former county of Kinross-shire has a strong local identity, centred on Scotland’s largest lowland lake: Loch Leven. There are sewage inputs to the loch from combined sewer overflows, there is regular pluvial flooding , and diffuse pollution from car parks, industrial premises and roads is evident. There are/were run-down areas of decaying infrastructure too. The raingardens challenge was designed and supported to address all of those issues. The first challenge to address was language: few people know what is meant by SUDS (with or without upper case U) and it’s a clumsy term even for professionals “a SuD” “SuDS systems” etc. By contrast “rain” and “garden” are two terms which are well understood, so we defined a raingarden as ”A vegetated area designed to accept rainfall runoff”. That covers every soft engineering type of SuDS feature we found or created. Dialogue became straightforward.
SuDS features:
- Willow swale (at car park edge, Dance connect, Kinross)
- Wildflower swales (Kipper Hire, Kinross, and Link Road swale)
- Street edge mini-swales (short mown grass) in housing
- ‘Natural raingardens’ unmown wet grass features at lower end of overspill car parking, Kirkgate Park
- Detention wetland (West Kinross Link Road)
- Gravel drains leading to treatment wetland, Bridgend Industrial Estate
- Wild vegetation wetland detention basin (Bridgend Industrial estate)
- SuDS ponds (3 housing developments)
- Permeable pavement (most frequent)
- Subsoil mega soakaways (dubious practice!) school & housing, Kinross
- Retrofit raised bed raingardens (one private house plus Portmoak Primary school)
- Infiltration swales (retrofits at Kinross Park & Ride)
- Retrofit planted channels and mini-basins (Loch Leven’s Larder)
Award category:
Community SuDS
Submitted by:
Scheme location:
Westerham Avenue, Haselbury Road, Park Lane, Haselbury Ward Enfield, N9 9BS
Summary:
The Moore Brook is a “lost” river in the highly urbanised area of Edmonton. The catchment is subject to flash flooding, and the river itself suffers from pollution. Two wetland schemes were delivered in the river catchment, Firs Farm and Pymmes Park Wetlands. However, there is significant residual surface water flood risk, which modelling as part of the London Strategic SuDS Pilot demonstrated that densely distributed Green Infrastructure SuDS (GI SuDS) such as rain gardens across the catchment will be able to address.
This approach of utilising GI SuDS would form part of a wider package of measures to improve walking and cycling in the Haselbury area. This led to development of the Haselbury Neighbourhood Improvements scheme, of which the Moore Brook Green Link, a walking route from Firs Farm to Pymmes Park Wetlands, is a significant part. The route itself would be lined with rain gardens.
The interventions are designed to ensure that multiple benefits are achieved, for example many of the rain gardens are utilised as horizontal traffic calming measures, facilitate new and better crossing points, and help to achieve other parameters of TfL’s Healthy Streets objectives.
SuDS features:
- Rain Gardens
- Rain Garden Tree Pits
- Permeable Paving
- Swales
Award category:
Catchment based SuDS solutions
Submitted by:
The London borough of Enfield
Scheme location:
Blossom Lane, Enfield EN2 0TG
Summary:
The Four Hills Estate is made up of 6 blocks (70 flats) on Blossom Lane. The frontage of the properties historically had grass areas but these were later asphalted over to create a vast area of impermeable paving.
The estate is part of the Enfield Town catchment which is prone to flooding. There is significant residual surface water flood risk, flood modelling demonstrated that densely distributed green infrastructure such as rain gardens and detention basins across the catchment will help to reduce flood risk.
The scheme relies on infiltration but connects back into the sewer system to deal with exceedance flows. We have designed domed gully covers to reduce the risk of the gully becoming blocked, further reducing the flood risk.
We have introduced a new footway which runs parallel to the road, improving access for residents and provide a safe means of egress from parked vehicles. We also installed permeable desire-line pathways behind the estate. In addition, the scheme now provides step free access to all ground floor flats and the paving has been designed to offer the residents an area away from the public footway which has helped build a sense of community in the blocks.
SuDS features:
- Swales
- Rain Gardens
- Detention basins
- Overland flow paths
Award category:
Regeneration and retrofit – small scale (less than one hectare)
Submitted by:
Meristem Design and London Borough of Waltham Forest
Scheme location:
Waltham Forest
Summary:
Over 60 community rain gardens across Waltham Forest. Many ofthe rain gardens are at the end of residential roads diverting surface rainwater from entering the water table. 600 sqm of continuous rain gardens along Forest Road cycle lane. Local residents and schools joined up to assist with the planting, learning about the species planted and the importance of the rain gardens.
SuDS features
- Raingardens
Award category:
Community SuD
Submitted by:
Scheme location:
Hengist Way, Cliffsend - CT12 5LQ
Summary:
Thanet Parkway Station is a new rail station situated between Ramsgate and Minster designed to accommodate future expansion of housing planned for the local area. The site is served by a 300-space car park situated off Hengist Way, Cliffsend and incorporates pedestrian, cycle and public transport connections to the surrounding area. The existing site is relatively isolated agricultural land adjacent to the existing railway with an underpass connection to surrounding fields.
Offsite drainage is not a viable option for this site and infiltration rates are relatively limited. The scheme uses maximisation of infiltration area through a variety of systems to achieve total on-site drainage without requiring additional land or impacting beyond the site boundaries.
These systems include infiltration swales and pond, direct infiltration through areas of the new car park via permeable paving and a tank storage/infiltration system for isolated areas of the site. The majority of drainage is linked to a new pond either for direct infiltration or to provide overflow capacity and storage in the case of large storm events.
Bullet point of SuDS features:
- Infiltration paving with storage media (Type 3 granular material) and soakaway beneath.
- Bioretention soil lined infiltration swales capturing both overland flow and highway run-off
- Infiltration pond accommodating both highway run-off, roof/platform drainage and overflow capacity from remaining areas of the site
- Polystorm crate retention and infiltration system capturing run-off from isolated areas of the site
Award category:
New commercial development (any scale)
Submitted by:
Scheme location:
Cheshunt, Waltham Cross EN7 6HR
Summary:
The new proposals form a Reserved Matters Application for 15 new homes and associated landscape on a 0.49ha site, recently submitted for Planning in April 2022. These Reserved Matters address an earlier Outline Planning consent from 2015.
The existing brownfield site is the former Fourfields elderly care home, in Cheshunt, which has been empty for many years. The site gently falls from the western boundary to the southeast with a difference in height of 2m, with steep northern boundary banks and a flatter central area. The underlying soil structure is impermeable and there are no existing SuDS features on site. The stormwater discharges directly into Rags Brook located about 15m to the south, flowing in a west-east direction
The Reserves Matters new proposals completely reconfigure the Outline masterplan with the SuDS strategy now becoming the starting point as well as the fulcrum of the new landscape-led masterplan for the proposed 15 homes. Within a relatively small site, fitting in 15 homes with their statutory garden sizes whilst preserving the existing tree belt, and including a new nature-based SuDS solution, was a challenging task.
A speedy successful outcome would have been difficult without the new masterplan being landscape-led, with nature-based SuDS features considered at the commencement of the design process, which started with an extensive assessment of the relationship of the site with its surrounding environmental and urban context. The outcome was the immediate production of a very early sketch design revolving around a strong nature-based SuDS strategy.
The final successful developed design was achieved through an iterative multidisciplinary process, with early involvement of each discipline, where each team was driven towards achieving the same cohesive goal.
SuDS features:
- communal rain gardens with free-draining soil within a relatively small site.
- roof downpipe bioretention flow through planters at the front of each plot
- Roof RWP Water Butts at the back of the plots (300L units)
- Permeable Paving (vehicular and pedestrian).
- SuDS Tree Pit within hard landscape surface and suitable SuDS tree species within rain gardens.
- Exceedance and flowpaths to low point landscaped areas within the site away from buildings’ thresholds.
- green roofs on refuse stores (Approx. 1.6sqm each. Total Area: 24sqm).
- green roofs cycle stores (Approx. 1.5sqm each. Total Area: 23sqm).
Award category:
Early housing scheme – not yet completed
Submitted by:
Scheme location:
Dales brow, Salford, M27
Summary:
The project transformed an uninspiring area of mown amenity grassland into a haven for wildlife while also diversity water away from the combined sewer system. The once underused area is now a valuable recreational greenspace for local residents.
The system is designed to intercept rainwater that runs off the Dales Brow and Folly Lane road surfaces, diverting it away from highways drainage and combined sewers into the swales. In heavy rainfall events the rainwater travels along the swales and into a temporary wetland area, providing emergency storage. Water moving around the swale system is slowed by a series of check-dams, cleaned by biofiltration, before being allowed to return to the Deans Brook via a pipe connection.
The project was a collaborative partnership between the City of Trees, Salford City Council, Environment Agency, United Utilities and the University of Salford
SuDS features:
- Swales
- Wetland
- Hedge
- Meadow
Award category:
Regeneration and retrofit – small scale (less than one hectare)
Submitted by:
Scheme location:
Mindenhurst Development, Deepcut, Camberley GU16 6QP
Summary:
The Mindenhurst Development is a new housing development which will provide 1,200 new homes in the heart of Surrey. It is redeveloping the military site of Deepcut formely know as Princess Royal Barracks. The drainage strategy has been designed in harmony with the topography of the site and its overall discharge into Basingstoke Canal which is a protected watercourse due to its rich and rare biodiversity.
The strategy has been designed to accommodate rainfall events of up to 1 in 100 year event plus an additional allowance for climate change of 40% increase in rainfall intensity. The scheme includes 1,200 new dwellings, new road and utilities infrastructure, amenity buildings and 45ha of green spaces.
Due to the designation of Basingstoke Canal, SuDS are key in providing filtration as well as slowing down water velocities which both allow pollutants to settle out. As the SuDS follow the natural topography of the site, a number of varied habitats have been created which help to establish a self-supporting and resilient ecosystem
SuDS features:
- New swales with check dams
- Existing ditches cleared and re-used
- Detention basin
- Pond
- Wetland vegetation
- Pervious pavement
- Filter drains
Award category:
Early housing scheme – not yet completed
Submitted by:
Southend City Council, Mott MacDonald
Scheme location:
Marine Parade, Southend-on-Sea SS1 2EJ
Summary:
Large SuDS retrofitting scheme in the public realm area of Marine Parade incorporating raingardens and permeable pavement. The SuDS integrates elements including HVM infrastructure and art/streetscape elements.
The scheme has been completed to concept design stage (3 options) The site area is 2.2ha and the coverage of SuDS ranges from 0.2ha (Option 1) to 0.5ha (Option 3). Option 3 provides a dramatic transformation in the landscape of Marine Parade with Nature-based Solutions and incorporates surface water re-use (water buts / rills). This will reduce the demands from water supply systems in the area (e.g., toilet blocks, irrigation, cleaning, fountains, etc.) delivering sustainability and climate resilience.
Runoff from the highways is intercepted by the SuDS and attenuated and re-used where possible. The connection is into the Anglian Water surface water sewer at a restricted rate. The scheme will reduce the pressure into the sewerage assets improving their resilience against the impacts of climate change, as the combination of peak rainfall intensity increase and rise in sea levels could impact their performance.
The scheme intends to install monitoring systems which will provide data to assist in flood warnings and learning points on the performance of SuDS systems.
SuDS features:
- Raingardens with surface water runoff attenuation and re-utilisation i.e., rills/stream
- Permeable pavement
- Green Roofs & walls
Award category:
Regeneration and retrofit – large scale (more than one hectare)
Submitted by:
Scheme location:
Erith Hills, London Borough of Bexley DA8 1FN
Summary:
The site is developed on a former quarry, which was subsequently used as a landfill. The nature of the landfill site provided little environmental benefit and, due to an impermeable capping layer on top of the landfill waste, was a significant contributor to local surface water flood issues. The capping layer was to be retained and enhanced as part of the proposals due to the elevated levels of gas within the underlying ground.
The scheme comprises 849 dwellings, a 630-place primary school, public open space and an 12-acre ecology zone, where a swale, attenuation basin and wetlands with a viewing platform are provided. Initial rainfall interception is carried out via tree pits and rain gardens. Numerous flow controls have been utilised within the site and, in combination with attenuation features, controlling the surface water flows discharged to a receiving Thames Water public surface water sewer.
SuDS features:
- Swales
- Detention basins
- Rain gardens
- Tree pits
- Permeable surfaces
- Filter drains
Award category:
Early housing scheme – not yet completed
Submitted by:
Scheme location:
The SuDSlab at Hull University
Summary:
The SuDSlab UK sensor array and network monitoring scheme encompasses the entire campus of the University of Hull, an attractive urban realm incorporating a wide range of SuDS assets and green open spaces. The campus is low lying and highly vulnerable to flooding. The scheme includes SuDS features, sewers, soil and groundwater and campus-wide weather data. The components range from historic features from the 1960/70s to modern rain gardens, raised planters and extensive development-level integrated SuDS management trains involving swales, basins and pervious surfaces with controlled sewer discharge. The components manage and monitor surface water during heavy rainfall and provide amenity and biodiversity year-round. The sensors array records data every 5-15 minutes from SuDS assets, boreholes, soil and weather stations providing a real time hydrological picture of the campus. A publicly available dashboard will share live information and communicate the benefits of SuDS to wider audiences. Raw data will be streamed for University students and researchers to analyse, improving understanding of how SuDS control water flow rate and filter pollutants, as well as the correlation between weather, infiltration, groundwater/aquifer status and conductivity. The scheme is measuring flow, depth, conductivity, soil moisture, weather, rainfall, temperature and air quality.
SuDS features:
- Swales
- Detention basins
- Rain gardens
- SuDS Planters
- Green roofs
- Pervious Surfaces
- Green wall
- Infiltration basins
Award category:
Catchment based SuDS solutions