portfolio
scott fairley MA landscape architecture 2015
heterogeneity
heterogeneity
Definition:“a heterogeneous entity is one composed of dissimilar parts-parts which may nevertheless be connected”
The cell as a model for heterogenity Nuclear Membrane Nucleus
Mitochondria Cell Wall Cell Membrane Chloroplasts Vacuole Cytoplasm
“a homogeneous entity is one where all components are settled and are in a measure of equilibrium
heterogeneity
12 linear metres
50c m
1m
These tools have been designed from first principles to make use of remote sensing and GIS to determine the relative heterogeneity of landscape; specifically, in this instance, to map the progression of restored coal workings to a more heterogeneous, and therefore, biologically-functional condition. However, these tools, with some modification, could be deployed to measure relative heterogeneity in any landscape, even urban or peri-urban systems, provided the definition of what comprises a “landscape element” is clear.
2m
measuring heterogeneity
6 linear metres
3 linear metres
relative lengths of edges the total combined lengths of the edges of all different landscape components within a given area where a greater combined linear distance of edges would imply greater heterogeneity
average size of landscape elements whereby sites comprised of fewer, larger elements can be described as being less heterogeneous than those comprised of a greater number of smaller elements
relative frequency of elements in more heterogeneous systems higher- suggesting greater complexity and greater scope for diverse interaction
heterogeneity in the landscape compositional heterogeneity
applying the concept of heterogeniety to the landscape we begin to refine both finer meaning; two different but fiundamentally connected aspects of heterogeneity emerge a more heterogeneous landscape is a landscape with a larger variety of different cover types (compositional heterogeneity) and ⁄ or a more complex spatial patterning of them (configurational heterogeneity)
configurational heterogeneity increased configurational heterogeneity, of course, requires a certain level of compositional diversity to express itself but can, through complex arrangement generate powerful edge effects and environmental gradients arguably, at increasing scales, incresed compsoitonal heterogeneity may simply begin to create repeating patterns combining both compositional heterogeneity
heterogeneity
location
It is perhaps not adequate to describe conditions at the Wyre as being defined in terms of the land’s relationship with water- the central plain of the region described as the Wyre, from East of Wyre estuary at Knott End to the Cocker channel has been created though the exclusion of the estuarine waters of lower Morecambe Bay. The land has, in phases over centuries, been further bolstered and buttressed ti exclude the action of the sea and the the holding (and “holding” is apt here) has been consolidated.
One of the inevitable results of seeking to produce an IMPERMEABLE edge to the sea has been the containment of the waters being propelled down, from the catchment in the fells to the East particulalry in the supposedly increasingly acute flood events in the Winter. The loss of upland forest, riparian woodland and modern farming practices are now featuring in the debate, as is the increasing area of impermeable surfacing within the urban fabric are also now being cited as contribuants.
The Wyre
location The attempt to modulate the TENSION between wave action, tidal surges and
more violent swells at sea, and greatly increased water entering the CRUCIBLE that the Wyre has, through such CONTAINMENT, become has enjoyed mixed success. Two major flood events in the last decade or so have challenged the UK Environment Agency to revisit its various flood defence strategies (see below). The result of an analysis of the strategy of containment, detention of water and exclusion of sea water to defined edges has been to HOLD THE LINE. A strategy which appears to assume INFINITE RESOURCES in creating and maintaining such defences, and defies the logical application of any COSTBENEFIT ANALYSIS.
Clearly, in the highly built-up areas of Fleetwood at the Westrn edge of the area, as well as the settlement of Garstang further inland there could be an argument in creating HAVENS, where contsrained areas area protected. This argument could also be applied to high-value assets such as the power station at Haysham. Conversely, some of the farmland in the central engineered plain of the Wyre, could be looked at as providing a powerful SINK to MODULATE and DAMPEN peak water events.
The Wyre
The Wyre coastal conditions: a series of impermeable barriers
Inland conditions: highly productive & engineered system Inland waterways
Clearly constrained field systems
Sea defences as public space
Grazing at high intensity
Long view of the effective topographical gradient
Estuarine waters: outside the barrier- dynamic landscape
Water drained & directed
Moorland: arrested development
Personal Proposition
personal proposition To challenge the rigid and impermeable NOTIONAL coast of the Wyre using the principle of increased POROSITY, thereby producing a more HETEROGENEOUS landscape
Porosity WHAT IS POROSITY?
precedent
the converse condition to POROSITY is IMPERMEABILITY where compounds are SELECTIVELY filtered out or prohibited; where these interactions are energetic in nature, FORCES may need to be RESISTED the resistance to forces such as hydrostatic pressure (waterproof clothing), wind (windows and external building treatments) or wave or river forces (flood defences) is inevitably subject to weathering where the impermeable barriers eventually need to be bolstered, repaired or replaced
MORE INTERFACES & REACTION ZONES
A GREATER DIVERSITY OF FORM EXCHANGE AND POSSIBILITY
water containment requires enormous amounts of engineered strength (& embodied energy) to resist the power of millions of tonnes of water in motion- this energy must be absorbed and disspated by an corresponding opposite force- this energy is lost
MORE SPACES, VOIDS REACTION “CRUCIBLES”
How can porosity be expressed in the landscape? modulated porosity in plan view
Porosity
How can porosity be expressed in the landscape?
Porosity
modulated porosity as exaggerated section
by describing the areas of relatively high ground in the landscapes as HAVENS, or areas where high-value development or infrastructure might be protected, and areas of low and/or marginal value land might be allowed to admit water in different ways at different times as SINKS, we could, through careful modulation of topography and defences, create a more diverse and resilient landscape.
How can porosity be expressed in the landscape?
Porosity
coastal porosity modelled over time
impermeable
modulate barriers
open conditions
complex, indeterminate outcomes
Porosity How can the concept of porosity be applied to a creative and positive modification of conditions at the Wyre? The creation and maintenance of the flood defence barrier between the sea and the study area (right) limits the potential reactive zone, or interface (between land and sea, river and land, sea and river) to a single, narrow strip. The non-return valves fitted to freshwater discharge pipes which run through the flood defences allow for some measure of interaction along the environmental gradient of fresh & salt water. By gradually increasing the POROSITY along the strong barrier, allowing the controlled but definite admission of tidal water into the study area, the energy striking (and damaging) the sea defences will be dissipated into a broad intertidal zone. Conversley, fresh water will be more broadly distributed along a far more diverse and heterogeneous ecological network. THE ANTHROPOCENTRIC BENEFIT OF INCREASED TIDAL RESILIENCE IS GENERATED WHILE PRODUCING THE BIOCENTRIC BENEFITS OF INCREASED HETEROGENEITY AND MORE DIVERSE ECOLOGICAL NETWORKS- ONE IS THE RESULT OF THE OTHER
tidal surge to open estuary tidal surge directed by dykes
tidal surge to open estuary moderate barrier estuarine discharge to sea
strong barrier moderate barrier
drains discharge to sea- no-return valve STUDY AREA
drains discharge to sea- no-return valve area of potential dynamic sink
Porosity
detail design
Porosity
Coastal defence can be described in terms of four key strategies 1 2 3 4
Hold the line - Where existing coastal defences are maintained but no new defences built. Advance the line - New defences built further out to reduce the stress & extend the coastline Retreat the line - Move people out of danger & allow a fall-back position to be established. Do nothing - Deal with the effects of flooding and erosion as they come or just ignore them.
CONVENTIONAL COASTAL DEFENCE CONFIGURATION
MANAGED REALIGNMENT BREACH OF DEFENCES
A specific strategy under the heading of “retreat the line” is “managed realigment”, so-called as it involves identifying candidate areas where the sea can be allowed to breach static sea defences. Tidal water can then enter a typically lightly-populated area and be dissipated over a relatively large area, rather than striking sea walls and dykes with correspondingly more force further out.
Porosity
Benefits of new intertidal habitats principally biocentric in nature Although the decision to undertake managed realignment of flood defences is generally catalysed by the financial pressures of maintaining fixed defences, the biocentric benefits are often profound. managed realignment could reasonably be described as ecological restoration, since many of the habitats created mirror those lost when the sea was excluded in the first place; broad mud flats, reed beds and estuarine habitat. The process of managed realignment can also carry some of the biocentric prejudices also seen in the ecologcal movement, such as the creation of biological reserves where humans, other than in the role of passive observers, can find themselves excluded.
high tide replenishment of pore
low tide draining of pore, air for trees exposure of food, removal of waste
spring/storm tide scouring of pore realigment +re-sorting a new equilibrium
creation of intertidal habitat produces a welcome biocentric enhancement, although anthropocentric benefits are limited through poor access to space longitudinal movement of water in peak events may need containment
the pore
land previously lost (whether farmland, recreation land etc) to enable the realigment & creation of the new porous system is designated as ecological land and can no longer deliver direct anthropocentric benefits such as housing, farming, energy generation or leisure
hard secondary defences costly to maintain also static & inflexible in practice
Porosity
Rather than creating an exclusion zone to human activity,could not this new condition of POROSITY not deliversimultaneous anthropocentric benefits to the biocentricby-products of a more cost-efficient form of coastal defence?
THE PORE: TOPOGRAPHY
For the pore to function well it should admit tidal water from the sea, gradually diminishing its energy as it moves inland, while also admitting fresh water from the land and allowing it to dissipate before discharging into the sea. In order to deliver these functions, the topography within the pore needs to be very carefully modulated.
TOPOGRAPHY ALONG THE LONGITUDINAL AXIS NEEDS TO RISE GENTLY MOVING INLAND BUT WITHIN THAT CONSTRAINT VARIOUS TOPOGRAPHICAL INTERVENTIONS CAN BE UNDERTAKEN TO PRODUCE VARIOUS EFFECTS
Porosity
THE EXTENT TO WHICH THE TOPOGRAPHY AT THE EDGES OF THE LATERAL AXIS IS ALTERED WILL MODULATE THE EXTENT OF THE PORE AND HOW ENERGETIC CONDITIONS ARE WITHIN IT
THE PORE: BENCHES Mediation of the topography in the PORE should be undertaken in order to create effects. Topographical amendments should be described in intervals o. ca. 2metres, in well-defined BENCHES. Each of these benches, depending on how far they are the pore’s sources of water energy (either river water or wave action) will impart a certain level of protection (a HAVEN) or water dampening (SINK). By implication, elements found in a HAVEN will be less vulnerable to elements found within SINK.
Porosity TOPOGRAPHICAL INTERVENTIONS: COMPOSITE ACTIONS
These differing levels of VULNERABILITY will directly inform the type of equipment, infrastructure or housing which will be most sustainabile in each BENCH.
TOPOGRAPHICAL INTERVENTIONS: SINGLE ACTIONS
B
B
No baffles: any water entering the pore which exceeds the volume capacity available washes into low ground
B
B
Bunds & banks: creating bunds along edges of sinks increases volume of sink while allowing excess water to overtop
B
B
Ditches & ponds: the creation of ditches perpendicular to the coast allows water to be conveyed towards or away from land
B
Woodland areas: while not able to withstand high salinity, some trees will tolerate relatively salty conditions in saltmarsh lessening wave forces and transpiring
B
B
B Woodland + Bunds: combining trees with bund features allows the bunds to protect the trees from wave action and excess salt while allowing the trees to reinforce banks
B
B Woodland + Lagoon: combining trees with pools of water will buffer salinity, impound water and baffle wave force within a matrix of tree roots which will reinforce the system
Porosity
THE PORE: SINKS & HAVENS
Neutral topography: water can move fairly freely within the pore. Tidal energy dissipated gradually. Land intertidal along a long gradient. Biocentric.
INTERTIDAL ZONE
DYKE
ESTUARINE ZONE
A
DEFENCE
A
Modulated topography: through balanced cut and ďŹ ll ponds and lagoons interact with banks and islets to create a heterogeneous & more accessible space.
LAGOONS (SINK)
ISLET/BANK (HAVEN)
PORE (SINK)
REEDBED/BANK (HAVEN)
INTERTIDAL ZONE
A
DEFENCE
ESTUARINE ZONE
DYKE
A
ESTUARINE ZONE
ESTUARINE ZONE
LARGE ISLET/BANK (HAVEN)
PORE (SINK)
A
REEDBED/BANK (HAVEN)
DEFENCE
A
DYKE LOWERED
Dynamic topography: by piercing & lowering tidal defences greater wave energy enters the space; stronger havens & sinks variously provide changing space.
energy generation in the PORE
Marine-source heat generation is in its infancy in the UK, but following the success of the National Trust Wales’ 300kw in 2014, confidence in the technology has been bolstered. Since this technology most efficiently produces heat, rather than electricity, the energy generated is most suitable for local use, such as village-level common heating schemes,or for small -scale industrial applications, such as a kelp-drying kiln, as are currently being developed on the Scottish Isles to service a growing market in seawood products.
One of the key efficiencies in the configuration of elements proposed here is the centralised processing and distribution of the power produced in the pore via a node, referred to as “the Dock”. The Dock is a central resource in that it will contain the necessary equipment to convert the DC electricty generated to AC for local use, will distrubute and monitor the heat generated by the marine-source heat pump and will, as much as is practicable, store this energy in order to dampen peaks and troughs in inherent in such renewable energy generation. EXPORTED ELECTRICITY
Porosity Onshore wind generation in the UK has had a problematic history and, rightly or wrongly,the debate around visual impact and the “protection of the countryside” persists. Offshore wind generation appears less contraversial and is likely to provide the bulk of future load.
CENTRAL POWER CONVERSION & DISTRIBUTION HUB: “THE DOCK” DOMESTIC HEAT
DOMESTIC ELECTRICITY
OFFSHORE WIND GENERATION
INDUSTRIAL HEAT USE e.g. KELP-DRYING KILN OPEN-SYSTEM MARINE SOURCE HEAT EXCHANGE ARRAY
COMBINED TIDAL POWER FLOOD GATE IN SUITABLE PORE CONFIGURATIONS
Power generation through the impoundment and release of tidal water has been around since middle ages (albeit on a small scale to mill flour). Current projects, such as the Swansea and Colwyn Bay tidal lagoon projects are on a very ambitious scale but it may be that the principle could be deployed at a more local level. Using the pore as the impoundment area, rather than constructing a large offshore breakwater could provide scalable cost savings, particulalry if the energy generated is for local consumption
ELECTRICAL TRANSMISSION VIA HIGH-VOLTAGE DIRECT CURRENT CABLES
HVDC cables, unlike AC cables, are able to transmit power over long distances with verylittle loss of energy. They also do not heat up like AC cables and require cooling. Perhaps most importantly, they are able to transmit power from a number of different frequencies, soare ideal when generation is aggregated and transmitted centrally, as proposed here.
energy generation in the PORE
TIDAL LAGOON SYSTEM CURRENT APPROACH
TIDAL LAGOON SYSTEM USING EXISTING TIDAL DEFENCES
ENERGY GENERATION IN THE PORE MICRO TIDAL LAGOON Despite being a mature technology (dateing back to medieval times when used to mill flour) the impoundment and release of tidal water has recently enjoyed a resurgence of interest.Major projects are likely to go ahead in Swansea Bay and later Colwyn Bay, whereby huge breakwaters are to be built out into the sea to generate vast amounts of power. In both cases, the inland areas of the towns are heavily built up, but in the case of where land withina candidate area for managed realignment is relatively uninhabited, the question begs: whether then configuration of the tidal lagoon could be REVERSED, whereby rather thanbuilding a large breakwater in the sea, whether the existing sea defence and the POREcould become the impoundment area, with the turbine relocated to the breach.
It may be that such an inverse tidal lagoon would work on an admittedly far smaller spatial scales than recently-consented schemes, but could be configured to deliver power directlyto local homes and businesses only, rather than sending most of its capacity out onto the grid. Also, the relatively tiny cost of such a project, should it prove scalable, could be attractive to community trusts or small industrial concerns.
LAND UNAFFECTED
IMPOUNDMENT AREA
TURBINE
BREAKWATER
(MODIFIES EXISTING FEATURES)
IMPOUNDMENT AREA
TURBINE BREAKWATER
(REQUIRES CONSTRUCTION)
SEA UNAFFECTED
Porosity
Porosity
RESPONSIVE HOUSING: BENCHES
Within the PORE, topography is lightly amended from the planar to catalyse certain effects: the creation of SINKS to detain water and create edges, HAVENS to protect key components, as well as a more general realignment or topography into key levels or BENCHES. Each of these benches will have key characteristics in terms of their DYNAMISM, VULNERABILITY, CONNECTEDNESS.
BENCH
dock & pontoons
EDGE SINK
inundated- tidal dynamic- daily housing- elevated
full stilt (2m high)
inundated-tidal dynamic- seasonal housing- part-elevated
part stilt (1m high)
FIELD
(REQUIRES CONSTRUCTION)
HOUSING TYPE
MAIN SINK
MARGIN
BREAKWATER
CHARACTERISTICS
inundated-continuous dynamic- seasonal housing- buoyant
inundated-seasonal dynamic- storm housing- permeable
through house
HIGH GROUND
inundated-1:20 dynamic- low housing- conventional
normal house
PROTECTED
inundated-1:200 dynamic- static housing- infrastructure
built-up over grade
Porosity RESPONSIVE HOUSING: HOUSING TYPES
In order to capitalise on the diverse opportuntiies for anthropocentric benefits presented by conditions within the PORE, will require building types and configurations that not only tolerant conditions within in it, but thrive on them. The dynamic water-centred conditions within the pore present key challenges, principally as a function of how water levels and ratesof movement can change over key cycles (TIDAL, SEASONAL , PEAK STORM EVENTS etc). For this reason, any housing proposed to be sited in or around the pore will need to be RESILIENT, FLEXIBLE & CONFIGURABLE.
the dock
pontoon through house
BREAKWATER
(REQUIRES CONSTRUCTION)
conventional house
split stilt house
protected infrastructure full stilt house
THE THROUGH HOUSE The through house responds to the projected threat of peak inundation events such as 1:20 year river flooding or temporally similar tidal events. The lower floor of the house is fitted with large doors which allow a central “through” conduit to be created while sealing the two adjacent lower wings of the house sealed against water using high thresholds and sealed gaskets. Externally, through houses are the most ‘conventional’ in appearance, and internally apart from an upside-down configuration (with living space upstairs with all the light-collecting windows). Houses of this type have been pioneered in the US Pacific Northwest as being “tsunami-resistant”, so should prove sufficiently resilient against Atlantic storms.
THE STILT HOUSE The stilt house configuration decribes any housing type which is significantly raised about existing ground level for the express purpose of avoiding flooding. The height of the stilt would be a function of the site’s flood vulnerability first and foremost, but may also be informed by other factors, such as wind exposure, visual impact or disabled access ramp lengths (as to comply with Building Regulations Part M). Stilt houses could equally be split into height levels, either to accomodate site topography or to provide a lower, accessible level and a higher, more protected level, for instance.
THE PONTOON HOUSE Pontoon houses not only respond to levels of existing or projected conditions of inundation, but they defy them: pontoons can be projected out into completely flooded areas. Their lack or fixed foundations allow them to be flexibly configured, realigned or even, depending on the design, moved from site to site. While clearly living on a floating structure is not for everyone, the pontoon configuration can provide a promising solution to dynamic coastal or estuarine conditions. The configuring of pontoons around a central DOCK, which centralises and delivers all of the infrastructural services which a development of pontoons might require, makes this approach flexible, adaptable and scalable.
Porosity
PONTOONS: CONSTRUCTION & CONFIGURATION
In order to best exploit the unique condityions found in the PORE, a floating arrangement of PIERS to provide walkways out to the PONTOON buildings is proposed. These structures are within the most topographically vulnerable parts of the pore, where conditions are generally inundated and/or subject to large variations in water depth. These structures respond by floating on an adjustble system of inflatable bags (depending on the required buoyancy), and being configurable in 2 dimensions via a series of piers with circular connectors which anchor to the bottom. These piers also convey essential services to and from the DOCK, which is the essential servie hub of any pore development.
Porosity Single residential/tourist unit, weatherproof & customisable
Double/stacked unit, weatherpoorf customisable & with stair access to 2nd floor bolt-on
floating piers are self-buoyant & fitted with service trunking with flexible connectors
PONTOONS: DESIGNS & FUNCTION
Swimming unit with diving boards & cage underneath to provide a deep and shallow end, as well as protection against jellyfish etc.
decks can be furnished with number of floats required and fixed togther, if required
Pisciculture deck with fishing points, floats/ropes for mussel culture, a winch for extracting ropes etc & small boat mooring.
Porosity THE DOCK: FUNCTIONS
WASTE WATER TREATMENT
WI-FI
SITE PARKING WITH RENEWABLESOURCE EV HOOKUPS
the dock
The DOCK is essentially a central service hub for the residential & functional PONTOON structures locations with a given PORE . As well as providing pedestrian & ramp (DDA) access down to the piers leading to the pontoons, the dock receives services, such as water and gas centrally and distributes them, via the service runs embedded in the piers. The dock also receives HVDC power from offshore wind and the tidal lagoon turbine and converts a proportion into 230v AC for use within the oating development. The remaining power is sent via HVDC onto the grid for remote conversion closer to the end-use. The dock also receives and distributes heat from the marine-source heat pumparray, as well HVDC POWER FROM OFFSHORE as collecting and treating waste water from the WIND AND TIDAL LAGOON dwelling units.
MARINE-SOURCE CLOSED HEAT PUMP ARRAY
dock wall playful water management system
Porosity Freshwater from land sources is mediated through an engineered water-attenuation system built into the dock wall’s structure. In this way the tension between strong tidal or storm water from the sea, and peak land-borne water loads is relieved.
UPPER RAIN GARDEN
TREE PLANTING
PLAY STREAM + STORM WATER DRAIN
PERMEABLE FOOT + CYCLEPATH
LOWER GARDEN GABION WALL
The structure also provides opportunities to interact with water. Any excess water not attenuated in the upper rain gardens is discharged into a shallow “play stream”, fitted with gravel and stepping stones to both slow the flow of water and to allow users to roll up their trousers and have a paddle. VEGETATION-PROTECTION FORESHORE
Performative vegetation: peat bunds PEAT BUNDS ARE TO BE PLACED TO DAMPEN LATERAL FLOWS OF WATER ACROSS THE PORE
PEAT BUND: MANAGEMENT The surface of the bund must be seeded with a resilient grass mixture as soon as the clay and soil cap has been installed. Therefore the bund can only be commissioned when such seed is likely to be able to germinate and enter active growth quickly. The the North-West of the UK, this would likely be in a range from late March to late October.
Conversely, the 2m willow cuttings or withies, which need only be driven through the soil cap into the peat core, need to be installed when the trees are dormant. The cuttings are generally supplied from December to March. If the willows were sourced and planted in the latter part of the season, there could be a narrow window whereby the sowing and willow planting could be undertaken in a single site visit. Provided the core of the bund does not dry out, the grass should become established quite quickly. The willows should have 600x600mm woven jute mulch mats in order to limit competition. The willows could be of any number of locally-appropriate species (such as Salix caprea, Salix pentandre, Salix vimnalis), provided they do not grow too tall. Ideally, local provence stoick could be harvested from nearby trees already growing succesfully.
The growth of the trees should be monitored to ensure they do not become so tall that they present a danger of failing at the root plate, as willows can be prone to do. The results of this monitoring will inform a coppicing cycle to enmsure that a good root-to-shoot ratio is maintained, and failure risk (that would damage the integrity of the bund), is minimised.
high-wear ryegrass-based grass seed mixture
blended soil/PAS 100 compost growing medium biodegradable fibre geo-grid
Once the trees are past their optimal height, at which they are growing well, but are apporaching a height which might present a failure risk, they should be coppiced. The coppicing cut height will likely be a function of local browsing animals- high for sheep, lower for rabbits, for example.
clay cap individual peat blocks
The resilience of the peat bund is a function of its composite structure. The peat will continue to draw and filter water into its core as long as it remains intact, and the trees and grasses which maintain that structure will continue to thrive. This is a key difference to “normal” conditions in engineered bunds where conditions are generally dry and establishment failures, in particular of medium to large-sized trees, tend to be prohibitively high. It is a functioning, biologicallydriven mechanism.
Porosity
Performative vegetation: moving woodlands woodland pattern changes over time planting +5 yrs
ALLOCATED WOODLAND ZONE
planting +10 yrs
INHABITED ZONE (SHORE)
planting +20 yrs INHABITED ZONE (PORE)
planting +40 yrs
Porosity
portfolio
scott fairley MA landscape architecture 2015