S H I F T I N G S A N D S A RESULTING INFRASTRUCTURE THROUGH SAFEGUARDING AMENITY NIGEL WYNNE SHIFTING SANDS a resulting infrastructure through safeguarding amenity The thesis research and investigation is a study of Dublin Bay, its threshold between land and sea, understanding the interaction between its built and natural environment and the challenges and qualities presented by this coastal landscape. Learning from its past, understanding its current context and looking to its future needs. Dublin bay and its edge condition is in constant flux, this comes in various forms and time lines, from the consistent ebb and flow of daily tides, to the gradual growth over years of Dublin port through reclaimed land. It provides for both economical and recreational aspects of the city with its ecological value paramount as a UNESCO biosphere. Its coastal heritage tells us a lot about our city and how it has shaped it. Building on this continuity raises the question: ‘How can we work in symbiosis with nature and our built environment to safeguard our amenity and mitigate rising sea levels?’ Thesis research looked at the built environment and the coastal landscape of Dublin bay. The connections between and along its coastal edge, to understand its relationship to its context. Investigations into how the intervention of infrastructure such as the North Bull wall or the Booterstown coastal rail line provided for an infrastructural function, yet through their interaction with nature, ecologies were created that have shown the potential for a symbiosis between manmade and nature. Infrastructure traditionally was influenced from anthropogenic values, heavily engineered solutions that meet the needs of its function but not the environment. Today our value system is changing, aware of the damaging effects of our anthropogenic past, we have to find ways to build in a symbiosis with our environment. Analysing hard and soft sea mitigation systems provided for knowledge of the potential solutions that could be applied to Dublin’s coastal edge condition. These were tested to understand the site context in respect to its unique topology, requirements and what would be appropriate. The nature of the investigation as part of a larger urban landscape brought to light the ability to understand the scale of the city, its connections and its impact from the macro to the micro. The thesis project focused on implementing the research and investigation in regards to testing a symbiotic solution within a site context. In parallel, this site context would be considered as a part of a larger urban strategy and its relationship within the city. Proposing to create connections and moments in a sequence of spaces that as Dublin grows and densifies, it will increasingly depend on such places that are accessible to all, well-connected by transport and rich with amenities. Proposing a ‘coastal blueway’, a necklace of public spaces along the water’s edge, forming an infrastructure and recreational edge condition to preserve amenity and mitigate rising sea levels with each intervention responding to its unique context. These ‘blue space interventions’ could become a new way of understanding the city, bringing previously unconnected places together. In total nine interventions are proposed as part of a sequence of spaces along the north edge of the coastal blueway. To test the thesis research at a detail level, the context of Bull island was chosen in its site potential. The title ‘shifting sands’ comes from the study of Bull Island and its formation through the initial manmade intervention of North bull wall in 1824. A piece of marine infrastructure to help prevent silting within the shipping channel to Dublin port. The sea wall combined through the natural process of sediment movement called littoral drift, which is caused by the prevailing currents and winds of Dublin Bay, formed Bull island gradually over 200 years, resulting in this UNESCO nature reserve island we see today. Further to the accumulation of the research and site investigation, the thesis project proposes a tidal sea wall to bridge the northeast tip of Bull island across Sutton creek to Howth head. In conjunction with this sea wall is a lightweight timber structure proposed along Dollymount strand to facilitate the initial stages of dune building, in addition to marram grass that at the latter stages, structurally knits the dunes together. Creating a predominantly soft infrastructure , ‘working with nature’ to create a barrier island and safeguarding its amenity value. Experiential qualities of the coastal environment investigated in volume one would be tested at the human scale, in the spatial interpretation of public baths as an embedded section of the sea wall. Testing how experiential qualities of the surrounding coastal environment could be translated spatially, socially and through materiality, giving an atmospheric, primitive quality to evoke the senses. Through the thesis research and investigation, the original first image ‘Palimpsest’ has come full circle, a reference to the layers of time and the visual clues left by it. In this case infrastructure through its materiality that comes from the landscape and eventually over time it then becomes part of the landscape due to the natural wind and water movement of ‘shifting sands’. 01 SHIFTING SANDS building with nature Image opposite SYMBIOSIS BETWEEN MANMADE & NATURE Temporal Study, North Bull Wall & Island, Dublin Bay. The combination of man made and natural process of littoral drift growing an island ecology over 200 years. 1825 1975 1900 2020 02 SYMBIOSIS working with nature Image right SYMBIOSIS BETWEEN HUMANS & NATURE Study of coastal activity - Kitesurfing, Bull Island, Dublin Bay. Video stills layered to express movement & experience - N Wynne Image below SYMBIOSIS BETWEEN HUMANS & PLANET EARTH Global wind patterns Image credit: earth.nullschool.net. minor image edit: N Wynne 03 COLLINS CHART 1693 JEAN ROCQUE 1757 DUBLIN BAY evolving threshold Images left TEMPORAL STUDY, DUBLIN BAY 300 years, an ever changing edge condition, N Wynne. Images below PALIMPSEST, Threshold between land and sea, Photograph: N Wynne. 0 01 02 03 04 KM 0 01 02 03 04 KM JOHN COWAB 1837 OSI - 2020 04 0 01 02 03 04 KM 0 01 02 03 04 KM PLACE understanding by physical experience Image opposite, RESPONDING TO PLACE, Precedent study (volume one), Steilneset memorial in Vardø, Norway, Peter Zumthor with artist Louise Bourgeois Image below, UNDERSTANDING PLACE THROUGH PHYSICAL EXPERIENCE, Walkscapes, Francesco Careri. 05 CONNECTING blue spaces and well being Image opposite BATHING HUT, RINGSEND. (early nineteenth century) Artist: James A. O’Connor Image below THRESHOLD, MITIGATION & CONNECTION, Test study, Volume one, Existing site condition, Sandymount, Model, Card, Balsa & Ply, N Wynne 06 MITIGATION safeguarding amenity Image right BATTLE OF CLONTARF 2020, Temporary mitigation measures, Photo: N Wynne. Line drawing overlay, North Bull Wall, Wooden bridge, Survey drawing, N Wynne. Image below, FLOODING CLONTARF PROMENADE 2014 - North Bull Wall - Wooden Bridge - Mean High Tide / SE Winds - Clontarf. Photograph: Dara Mac Dónaill / The Irish Times 07 INFRASTRUCTURE spectrum of mitigation Images right SPECTRUM OF COASTAL INFRASTRUCTURE. Hard to soft, illustrations by others as listed below: 01. Boatstrand Harbour, section of pier, Source: OPW library, National Archives of Ireland 01 02 02. Pier at Giles Quay, 47 th Annual Report from the Commissioners of Public Works in Ireland, 1879, p63 (Courtesy of Proquest, House of Commons Parliamentary Papers) Source: Researchgate.net 03. Kingstown harbour wall, (Dun Laoghaire) Source: OPW library, National Archives of Ireland 04. Booterstown sluice gates, Source: DLRCC, Illustration by: Naomi Mc Bride 05. Roman marine concrete, casting process, Vitruvius, De Architectura, (c. 25 BCE) 06. Half tide sea wall, Source: Researchgate.net 07. Sand fencing, Dune building and stabilization with vegetation (1910) Image credit: William Walton 08. Marram grass, Source: Countryside Commission, UK. 03 04 05 Image below SAND MOTOR, Netherlands, A dynamic solution, (2018) Nature based floor defense. Image: Joop van Houdt 06 07 08 08 BULL WALL & ISLAND N precedent - symbiosis Understanding the acting forces of nature Building with nature scale 1 - 25000 Bull island was formed by hydrology, a combination 04 of a man made intervention of the north bull wall and the natural process of littoral drift. Prevailing Winds Littoral drift is the process of sediment movement carried by prevailing currents and deposited on a sandbank or shoreline 03 Prevailing currents are influenced by the prevailing winds which in the case of dublin bay is south westerly. Prevailing winds are also critical to dune formation. Littoral drift has been growing bull island by 1-2 meters per year, prevailing winds in conjunction with marram grass has achieved dunes on bull island ranging from 2 - 9 meters. 02 Bull island evolution 01. 1825 (North Bull Wall) 02. 1900 03. 1975 04. 2020 01 Background aerial image source: OSI aerial map, 2005 0 2012. 09 PREVAILING CURRENTS BOOTERSTOWN MARSH precedent - symbiosis Images left BOOTERSTOWN MARSH ECOLOGY, Dún Laoghaire-Rathdown County Council, Publication: Biodiversity of Booterstown Marsh and Beach, Illustrations by Naomi Mc Bride Image below INFRASTRUCTURE, SYMBIOSIS BETWEEN MANMADE & NATURE, Dublin and Kingstown Railway, From Blackrock, looking across Dublin Bay towards WIlliamstown & Merrion. Dublin in the distance. Artist John Harris