Sites of Special Scientific Interest
Floods of 2014
Afforestation potential
Somerset Levels 1:200,000
SOMERSET LEVELS
FLOODING
The Somerset Levels are 648km2 of low-lying plains and wetlands in South West England facing an escalating risk of flooding due to the increased incidence of high volume rainfall in recent years. Its name derives from its topographical character as an almost uncompromisingly flat region sited an average of 6m above sea level; bounded by the Quantocks and Mendip Hills, many rivers and streams flow down onto the Levels, extending the catchment area to 1,700km2.
In the floods of 2014, approximately 115 km2 of land was inundated by 65 GL of water with 150 households suffering damage and many local communities, despite no direct water damage, cut off by flooded roads and rendered inaccessible without aquatic or amphibious vehicles for months. Affected agricultural land is estimated to need two years to recover former productivity. Flood warnings were issued at the end of December 2013 as heavy rain caused the rivers to swell; by early January, all had overflowed. Rain continued and evacuations were ordered a few days later with Somerset County and Sedgemoor District Councils declaring a ‘major incident’ on January 24th 2014. However, the situation worsened through to late February as temporary flood defences were routinely breached by fresh rainfall; only in midMarch did waters subside sufficiently for access roads to be reopened.
The convergence of so many waterways on the plains - where the flow rate is very low owing to the flat gradient of the landscape - presents obvious issues during extended periods of heavy rain, for once the saturation potential of the river basin has been reached, all drainage is carried through just three rivers: the Axe, Brue and Parrett. Originally extensive marshes with human habitation limited to the fringes and raised ‘islands,’ drainage and reclamation of the land has occurred for at least the last thousand years. The landscape is a patchwork of fields separated by drainage ditches, locally referred to as ‘rhynes,’ most with pollarded willows growing on their banks. These rhynes are a ubiquitous feature of the locality and inherently multifunctional: whilst drainage ditches transformed quagmire to pasture, they demarcate property and, in summer, operate as watering channels for livestock.
Flooding of the Levels directly disrupts agriculture, affecting 15,000 jobs; impacts on the transportation network impede access to many more as well as education, healthcare and supermarkets. In the most severe and pessimistic of scenarios, failure to adequately deal with this situation could lead to the displacement of whole communities and the abandoning of this rich farmland. Thus, severe flooding of the Somerset Levels must be mitigated to preserve nationally significant wildlife habitat, protect agricultural productivity and so safeguard local communities and national food security.
SOMERSET CENTRE FOR NATURAL BUILDING
Jonathan Davies
LSAP 10
SOMERSET LEVELS
Catchment
Contours
Waterways
Forest
Reforestation potential
Somerset Levels 1:250,000
Area 1
Area 2
Area 3
Area 4
Area 5
Area 6
Area 7
Area 8
SOMERSET CENTRE FOR NATURAL BUILDING
Jonathan Davies
LSAP 10
Area 9
Area 10
Area maps examined at 1:10,000
Client
The Comeytrowe Consortium
Offices throughout the UK and Europe
www.peterbrett.com Peter Brett Associates LLP BRISTOL Tel: 0117 928 1560 Fax: 0117 928 1570
Area plan 1:5,000 Land at Comeytrowe, Taunton Yeovilton Wind Rose 2012
Date
July 2013
Scale
N.T.S.
Drawn By
DW
Checked By
GH
Figure Number
Figure10.2 PBA BRISTOL J:\24721 Comeytrowe\AQ\Plans and Figures\ArcGIS
+ AA, HOOKE PARK Hooke Park is the Architectural Association’s woodland site in Dorset, south west England. The 150 hectare working forest is owned and operated by the AA and contains a growing educational facility for design, workshop, construction and landscape-focussed activities. It is used by visiting groups of Londonbased students, the Hooke Parkbased MArch Design & Make programme, and for short courses during the academic breaks. The forest was historically a deerhunting enclosure and is designated as Ancient Woodland. It forms part of Dorset Area of Outstanding Natural Beauty and is sited within an active farming landscape close to the market towns of Beaminster and Bridport and a few miles inland from the Jurassic Coast – a UNESCO world heritage site. This historic rural
landscape context provides a unique alternative to the conventional urban focus of city-based architecture schools. West Dorset is renowned for is rich craft and making traditions, food and rural cultures. The woodland is a mixture of broadleaved and conifer species that provide the prime source of timber for students’ construction activities. This ethical premise, of using the immediate material resource for building, was established in the 1980s in the three original campus buildings for the Parnham furniture college designed by architects ABK, Frei Otto and Edward Cullinan, and engineers Buro Happold. Following exchange of ownership to the AA in 2002, the campus development has continued with new workshop and accommodation facilities being designed and built by students of the AA’s Design & Make programme.
BRIGHTON PERMACULTURE TRUST rehabilitation of the environment and
CAT, MACHYNLLETH
Brighton Permaculture Trust is a charity that promotes greener lifestyles and sustainable development through design. They run courses and events, applying permacultural principles to their projects. Its aims are:
CAT is an education and visitor centre that demonstrates practical solutions for sustainability covering: environmental building, ecosanitation, woodland management, renewable energy, energy efficiency and organic growing.
1. To promote sustainable development for the benefit of the public by (a) the preservation, conservation and the protection of the environment and the prudent use of resources; (b) the relief of poverty and the improvement of the conditions of life in socially and economically disadvantaged communities; and (c) the promotion of sustainable means of achieving economic growth and regeneration. 2. To advance the education of the public in subjects relating to sustainable development and the protection, enhancement and
to promote study and research in such subjects provided that the useful results of such study are disseminated to the public at large. Sustainable development means development which meets the needs of the present without compromising the generations to meet their own needs. At the same site, Earthship Brighton represents the Low Carbon Trust’s first project and the first Earthship to be built in England. The project was constructed as a community centre for use by Stanmer Organics, built on a Soil Association accredited site in Brighton. The project has evolved over the last ten years, providing jobs for local workers and enabling people to come and experience an eco-build and be inspired to respond to climate change in their own ways back at home and work.
SOMERSET CENTRE FOR NATURAL BUILDING
Jonathan Davies
LSAP 10
The facility has become embedded in the UK’s sustainable development: as well as the visitor centre and on-site demonstrations sustainable solutions, CAT hosts schools, colleges and universities for curriculum-based learning, runs short courses for the public and specialists and has its own graduate school with postgraduate degrees in environmental architecture and renewable energy. Renewables installed at the facility include photovoltaics, solar thermal, biomass and combined heat and power (CHP), hydroelectricity, air
source heat pumps, a community heat main and a range of wind turbines with all electricity flowing into a local grid. Additionally, there exist two reed bed systems, an off-mains water supply and extensive organic gardens. One contribution of particular significance has been the instigation of ZeroCarbonBritain, a series of research reports addressing scenarios for reducing the UK’s emissions to zero in 20 years.
Roof Site plan 1:200 1:500
BIOMASS CHP
RAINWATER HARVESTING
COMPOST TOILETS
A biomass cogenerator in the working yard produces heat and electricity for the facility from wood shavings and trimmings collected during forest management. Insulated hot water pipes buried under the track convey hot water to the visitor centre and school.
As a very minor part of the flood prevention strategy, both buildings are equipped with rainwater tanks to collect runoff from the 1600m2 of roof. This non-potable water could then be heat-treated using the CHP’s output and refined for human consumption.
Compost toilets reinterpret our sanitation to capture effluent and enable its productive use. All toilets in the facility would be monitored regularly and emptied into compost bins in the forest: when full, it would decompose for 12 months before the compost is spread.
Area plan 1:5,000 Site section 1 1:500
SOMERSET CENTRE FOR NATURAL BUILDING
Jonathan Davies
LSAP 10
07 01
02 03
06
04 05
01 02 03 04 05 06 07
Sales office Tool storage CHP plant room Workshop Unisex toilets Sawmill Material storage
55m2 41m2 81m2 140m2 14m2 295m2 993m2
Working yard plan 1:200
SOMERSET CENTRE FOR NATURAL BUILDING
Jonathan Davies
LSAP 10
CIRCULATION The character of the centre is of the forest and it embraces both the floor and canopy. Designed to straddle an existing public footpath without impeding its flow, it offers extensive views over the floodplains. From the proposed off-road parking, a new raised walkway complements the trodden grass track and provides accessibility for all potential users of the building. The walkway leads visitors down a gentle slope as the ground falls away; the result is passage through the canopy which delivers visitors onto the roof platform for the primary viewpoint. A staircase integrated into the side of the building ducks back undercover of neighbouring trees to the entrance terrace, accessing visitor centre and classrooms. Stairs through the eco-shop leads onto the main landing, framed by the canteen and secondary viewpoint. A final external stairway descends to the lower landing where the public footpath continues through the fields: all this wraps around a supplementary lift block. Public functions are clustered around this circulatory core: toilets on the ground; canteen, eco-shop and lecture theatre on the first; and visitor centre on the second floor. Split across three levels, the building responds to the topography of the site whilst retaining accessibility. The sequence of movement through the building switches focus between wide-ranging views of the floodplains and intimate acquaintance with the surrounding forest.
Circulation diagrams 1:200
SOMERSET CENTRE FOR NATURAL BUILDING
Jonathan Davies
LSAP 10
SECOND FLOOR Classrooms Guest accommodation Visitor centre
FIRST FLOOR Eco-shop Kitchen Canteen Toilets Lecture theatre Private accommodation
GROUND FLOOR Public toilets Offices Private accommodation
Programmatic axonometric 1:250
Perspective of both buildings
SOMERSET CENTRE FOR NATURAL BUILDING
Jonathan Davies
LSAP 10
01 01 05
02
03
09
04 06
07
08
01 02 03 04 05
Private dwelling Offices Men’s toilets Women’s toilets Lecture theatre
60m2 54m2 16m2 17m2 38m2
Ground floor plan 1:200
01 06 07 08 09
Private dwelling Canteen Unisex toilets Kitchen Eco-shop
13
51m2 95m2 12m2 28m2 148m2
First floor plan 1:200
12
Section 01 1:100
SOMERSET CENTRE FOR NATURAL BUILDING
Jonathan Davies
LSAP 10
13
10 11
14 12
12 14 12 12 14
10 1 1 12 1 3 14
Common sitting room 35m2 Communal washrooms 37m2 Accommodation 97m2 Visitor centre 173m2 Classrooms 87m2
12
Ground floor decks First floor decks Second floor decks Roof deck Total
Second floor plan 1:200
12
12
12
130m2 91m2 234m2 239m2 694m2
Roof plan 1:200
10
08
07
06
01
04
03
02
01
Section 02 1:100
SOMERSET CENTRE FOR NATURAL BUILDING
Jonathan Davies
LSAP 10
CONSTRUCTION The structure is a hybrid, two halves combining very different approaches: rammed earth, grounding the building to the east of the footpath and raised roundwood timber with straw bale infill to the west. Crowning the building is the cantilevering visitor centre of timber truss construction bridging and reliant on both sides. This dichotomy showcases the range of structures, internal environments and finishes possible with natural materials. The construction is quite deliberately ‘skinny’ with an average internal width of 4m. This was driven by two considerations: firstly, quality of the interior spaces with regards to daylight and natural ventilation; secondly, smaller material dimensions required by short spans would result in a greater potential for the use of thinnings in construction. The first point was carried through to minimise the need for artificial lighting or mechanised ventilation, instead giving people control over the internal environment with operable vents and windows. Local availability was a must and both the soil for compacting and straw bales for infill are obtainable on or adjacent to the site. Planting trees and waiting for a harvest before commencing the build may be too speculative a strategy: however, sustainably practiced forestry in the vicinity can provide timber while the planting scheme is instigated. One known source within half an hour of the site practices continuous cover forestry, growing Douglas fir, European larch and Western Red Cedar to FSC standards.
Structural diagrams 1:200
SOMERSET CENTRE FOR NATURAL BUILDING
Jonathan Davies
LSAP 10
50mm coarse aggregate on grade 1.2mm EPDM membrane 100x20mm birch deck screwed below 100mm d. planed larch poles bolted w/ ventilated roof cavity 12mm strawboard skimmed w/ lime render 100mm d. larch poles screwed w/ 100mm Thermafleece 200mm d. larch poles lapped & bolted w/ 200mm Thermafleece 12mm strawboard 20mm lime plaster
100mm d. larch web member screwed 200mm d. douglas fir chord half-lapped
15mm polished limecrete finish 35mm lime screed w/ 15mm UFH barrier pipe 50mm precast limecrete panels 100mm d. planed larch poles lapped & bolted w/ 100mm Thermafleece 200mm d. douglas fir beam tenoned & bolted to columns w/ 100mm Thermafleece 18mm strawboard screwed 20mm lime plaster
300x30mm lapped scots pine boards screwed 50mm d. hazel wall pin at 500mm c. staked into bales w/ hazel staple 30mm lime render fireproofing 450mm straw bale infill precompressed & fixed w/ hazel stubs 200mm d. douglas fir column tennoned & bolted to beams w/ straw & clay packing 30mm lime plaster internal finish
180x450mm composite ring beam w/ 120mm Thermafleece insulation 100mm d. larch pole lintel bolted to columns
15mm polished limecrete finish 35mm lime screed w/ 15mm UFH barrier pipe 50mm precast limecrete panels w/ DPM 100mm d. planed larch poles lapped & bolted w/ 100mm Thermafleece 200mm d. douglas fir beam tennoned & bolted to columns w/ 150mm Thermafleece 50mm d. larch poles at 490mm c. screwed
200mm d. aspen piles at 2400mm spacing 200mm backfilled gravel 400x400x250mm compacted gravel footing
Detail section 01 1:20
SOMERSET CENTRE FOR NATURAL BUILDING
Jonathan Davies
LSAP 10