Closed loop Urbanism [Autosaved]
- 1. CLOSED LOOP URBANISM ONWUCHEKWA, OLUCHI VICTORIOUS M.A ARCHITECTURE I.D: 77165447 TECHNOLOGY FUTURES
- 2. CONTENTS INTRODUCTION -CLOSED LOOP URBANISM -KEY PRINCIPLES OF A CLOSED LOOP ENVIRONMENT -URBAN DIGESTION RECYCLING THE COAST -COASTAL WATER BODIES OYSTER AS A MEANS OF PRESERVING THE COAST -OYSTER BEHAVIOUR -LIFE CYCLE OF AN OYSTER PRECEDENTS -MOSQUITO LAGOON -LOXAHATCHEE RIVER - SAPELO ISLAND -JEREMY CREEK, SOUTH CAROLINA -TIBWIN CREEK, SOUTH CAROLINA -PAMLICO SOUND, NORTH CAROLINA OYSTER APPLICATION IN FORMBY -SHIFTING SHORES – LIVING WITH A CHANGING COASTLINE -PROPOSED STRATEGY CONCLUSION REFERENCES
- 3. CLOSED LOOP URBANISM Theme: Oyster as a means of economy in the coastal area Closing the loop generally means recycling, re-using and also turning “waste to wealth”. The important aspect of Urbanism is the human interaction with nature. The new urbanism is promoting a walkable, mixed-use neighbourhoods and transit oriented development, seeking to end sub urban sprawl and promoting the environment. There has been a growing recognition within the scientific community of the need for a more holistic and coherent approach to understanding the complex links between the seas and oceans on one hand, and human health and well-being on the other. Extreme weather events such as coastal storms and flooding, and human exposure to marine-borne pathogens and chemical pollution, pose significant threats to human health.
- 4. Closed loop Urbanism extends the remit of “sustainable urbanism” and creates a stand alone system where all production and waste are not to be thrown away, but recirculated and continually used. Closed Loop Urban systems require minimal (or ideally no) resources to sustain their existence. Key principles of a closed loop environment Materials sourcing Manufacturing Distribution Logistics Sales& Retail Consumption & Usage Product, Recycling & Materials recovery Raw materials Manufacturing process reuse Logistics waste and auxiliary products & reuse Waste from consumption Product and by- product reuse
- 5. Urban Digestion It is a type of model to facilitate the description and analysis of the flows of the materials and energy within cities, such as undertaken in a material flow analysis of a city. It provides researchers with a metaphorical framework to study the interactions of natural and human systems in specific regions. Solar cells connect solar energy into electricity Green roofs bind rainwater so that it evaporates Solar panels heat water All frontage and roofing materials are free from heavy metals Car pools reduce private motor travel Safe footpaths and bikeways Street rainwater is treated locally and flows into the lake instead of to a treatment plant Heat exchangers in water treatment
- 6. Recycling the Coast The coastlines are endangered. At no time in the span of human civilization have we faced such extreme and global threats to our marine ecosystems. Pollution levels in coastal habitats are reaching alarming levels. Heavy metal contamination is yielding some commercial fish stocks unsafe, and many species are exploited to the brink of collapse. Many of these sites on undeveloped natural coast are now suffering the knock-on impacts of hard engineering further along the coast. The defences are increasing and concentrating change to an internationally important sand dune formation and giving rise to problems for other coastal users. As sea levels rise and severe storms increase, it will become ever more difficult and expensive to build and maintain strong defences. They can also disfigure the coast and cause environmental harm by moving the problem to another location.
- 7. Sea level rise is likely to have a dramatic impact on low-lying coastal and intertidal habitats causing widespread flooding and accelerated coastal erosion. Ultimately, many coastal ecosystems may be lost or irreversibly altered. Rising sea level pushes the high-water mark landward; however, many coastal habitats are prevented from migrating inland due to natural or man-made barriers. The loss of coastal ecosystems would have profound implications for neighbouring human communities. Coastal habitats, such as mangroves, provide many vital services. For instance, they act as nurseries for pelagic fish, are a source of food and fuel, and are barriers against tidal surges and flooding. Recycling the Coast
- 8. Coastal water bodies Tidal creeks are very essential for early life stages of residents and also visitors (fishes and sea birds). They acts as guards to the coastal health. As water level rises and falls with the tides, the tidal creek combines salt water from the estuary with storm water runoff from the land. Habitats around the creeks like: • Marshes • Oysters • Open sand flats • Channels Huntington beach state park salt marsh Tidal creek is a productive ecosystem at the interface between terrestrial and marine habitats and they also intertwine with salt marshes which are important for conduits for energy and material exchange and acts as a necessity for providing vital resources for coastal communities. Sapelo sand marsh in Georgia Recycling the Coast
- 9. OYSTER AS A MEANS OF PRESERVING THE COAST
- 10. Oysters as a means of preserving the coast Oysters are sessile molluscs, which means they have two(2) calcareous shells that protect the soft body mass of the oyster and have an elastic ligament that controls the opening of the shell. Oysters are filter feeders, drawing water in over their gills through the beating of cilia. Suspended plankton and particles are trapped in the mucus of a gill, and from there are transported to the mouth, where they are eaten, digested, and expelled as feces or pseudofeces. Oysters feed most actively at temperatures above 10°C (50°F). An oyster can filter up to 5 litres of water per hour. Pacific oyster Crassostrea gigasequipped with activity electrodes to follow their daily behaviour 24/7 Oyster reefs form when densely packed individual oysters grow upward and outward creating a complex hard surface along the coastline. The reefs are a three-dimensional habitat, located in intertidal or subtidal zones. Recycling the Coast
- 11. Oyster Behaviour In terms of nutrient cycling, oysters are effective filter feeders and can have large effects on the water columns in which they occur. Oysters consume nitrogen-containing compounds (nitrates and ammonia), phosphates, plankton, detritus, bacteria, and dissolved organic matter, removing them from the water. What is not used for animal growth is then expelled as solid waste pellets, which eventually decompose into the atmosphere as nitrogen. Oyster reefs therefore can significantly improve water quality and clarity. Oyster reef at about mid-tide off fishing pier Oysters influence: • Nutrient cycling • Water filtration • Habitat structure • Food web dynamics • Controlling erosion (oyster reefs are natural breakwaters that protect shorelines). Bags of oyster cultch used in oyster restoration The Whaleback shell Midden in Maine contains the shells from oyster harvested for food dating Oyster
- 12. Oyster Oyster Behaviour (Life cycle of an oyster) Oyster reef development occurs in four(4) stages: initial colonization, clustering phase, accretionary phase and maturation. The initial colonization occurs with the settlement and growth of an oyster spat (larval baby oyster) and small, scattered clusters on a suitable substrate with a sufficient flow of water. The clustering phase occurs when more oyster larvae settle and attach to both dead and live oyster shells. Each small colony comprises three to seven(7) generations of oysters, although the majority dies from overcrowding and suffocation. In the accretionary stage, the small clusters increase in size and form a mass oyster cluster with growth occurring horizontally and vertically. Development of the oyster reef continues with the accumulation of live and dead oysters shells within the water level of the intertidal zone. An oyster reef reaches senescence, or maturation, when it can no longer develop vertically.
- 13. Oyster Behaviour Additionally the hard structure of the oyster reef stabilizes sediments to help improve water quality as well as provide shoreline protection. South Carolina Aquarium SCORE reef building project, Charleston SC reef bags. Individuals placing bags filled with oyster shells along the shoreline. Oyster reefs along the coastline. Effects of simulated harvesting evaluating the impacts and recovery of intertidal fishery practices, project followed recovery for 2 or 3 years. Oyster Volunteers help to deploy oyster bags in Salt marsh
- 14. Harvesting adult oysters interrupts this cycle by removing shell from the system. Replanting oyster shell is an important way of ensuring that suitable habitat is available for future generations of oysters. Complete the cycle by recycling! To properly manage the oyster beds and maintain these important oyster habitats, citizens and businesses must continually recycle the oyster shell that is removed from the state's oyster beds. Photo of recruitment of oyster shells (cultch) as part of SC restoration work A natural bed of very healthy intertidal oyster clusters at larva stage Oyster reefs along the coastline. Oyster Shell Recycling Oyster shells provide a scaffold for spat (young oysters) to settle on and grow. They can be placed on the sea bottom in areas with a natural supply of spat from existing oysters. In many areas there is not enough existing material for the spat to settle on.
- 15. Oyster shells Oyster mats are created Oyster bar Reef growth Sucked oyster shells reclaimed for use in oyster reef restoration project Recycled oysters are placed back into bay waters to replenish and restore reefs Harvested oysters sold to restaurants After the oysters are eaten the shells are discarded • Separate shell from trash. Shell mixed with trash is not suitable for recycling. Provide separate containers for shell. • Keep the shells in a porous container to reduce odours. • Bring the shells to a shell recycling center. • DO NOT put live oysters in waters. Placing imported oysters in our waters can create public health problems and may harm local oysters or other animals. • DO NOT put freshly shucked shell in waters. To avoid contamination, shell should be dried for 6 months. Recycling steps Oyster Shell Recycling
- 16. Precedents
- 17. Precedents
- 18. Mosquito Lagoon, Florida Mosquito Lagoon is located in the northern part of the Indian River Lagoon system and the Atlantic intercostal waterway. It is a popular site in the Indian River lagoon, located in one of North America’s most diverse estuaries. The Mosquito Lagoon Park is a campground with cabin rentals located in Oak Hill, Florida in Volusia County on the banks of the Mosquito Lagoon. We are a fairly new and still growing small community with waterfront spaces on the bank of the beautiful Mosquito Lagoon. This area of Florida is known for some of the best fishing in Florida. Precedents
- 19. Mosquito Lagoon, Florida Threats: • Reduced water quality due to manmade hydrologic changes, non-point source pollution, loss and fragmentation of habitats, overuse/overharvest of resources, and the threat of invasive exotic species. • Stormwater runoff problems are compounded in urbanized areas. • The boat wakes are dislocate the live oysters from their reefs, in which they stumble against themselves and die eventually forming barren islands of oyster shells. • Invasive exotic species occur in all portions of the lagoon watershed, from upland habitats to wetlands to aquatic habitats within the lagoon to adjacent coastal habitats. Exotics compete with and often crowd out native species, greatly reducing ecosystem biodiversity and function. Precedents
- 20. Precedents Mosquito Lagoon, Florida Strategies • Use of oyster mats to restore dead reefs, position within shallow waters of the lagoon. • These mats form a huge welcome mat and welcome free floating larvae and produces backbones of new, healthy reefs. Creating oyster mat, tying up 36 oyster shells which they are carefully pre-drilled with a hole A floating backhoe, donated by partners, helps prepare a restoration site. The machine has eliminated the need for tedious, back-breaking hand-raking – moving the project ahead by years.
- 22. Key Benefits: • Water filtration • Provide food and nurseries for other aquatic animals • Stabilizes the eroding shorelines Weighed and connected together, in which the oyster mats provide a stable foundation for oyster larvae that has been spawned and fertilized. Volunteers spend the day among the knee-deep waters of the lagoon, placing oyster mats into the prepared site. The mats allow new reefs to form within 18 months. Precedents
- 23. Loxahatchee River, Florida Precedents Loxahatchee river is a 7.6 mile river near the southeast coast of Florida. • It has a tidal influence that begins below Trapper Nelson’s cabin. • The river is particularly narrow for most of the area above Trapper Nelson’s cabin • There are many low branches and overhangs • The currents can be strong depending on water levels Open water: Below Trapper Nelson’s cabin the river widens considerably. Contact with motor boats is possible and high winds are more likely closer to the state park boat ramp. Wildlife: American alligator, osprey, white-tailed deer, great blue heron, mullet, brown water snake, cottonmouth snake, yellow-bellied slider.
- 24. Precedents Loxahatchee River, Florida Threats: • Oyster reefs have been declined due to lack of hard surfaces where larvae can attach. Long assumed to improve water clarity and benefit other species of aquatic life. • Large freshwater releases reduce salinities in the estuary to levels that harm estuarine and marine flora and fauna with oyster and seagrasses being among the most notable. Comparison of storm-related flood control releases from S-46 at Loxahatchee River, Florida. Salinity Subsequent assessment of oyster communities indicated severe impacts to oyster reefs in the Southwest Fork and moderate impacts to oysters in upstream reaches of the Northwest Fork. Typical salinity envelope for the Oyster Reef site at river mile 4.1 in the Northwest Fork of the Loxahatchee River, Florida. Dashed and solids lines are the lower and upper bounds of the envelope shown as the cummulative distribution plot of the daily minimum and maximum salinity recorded by a datasonde at 15 min
- 25. Precedents Loxahatchee River, Florida Oyster Recruitment Monitoring 2007 - 2013
- 26. Precedents Loxahatchee River, Florida Strategy: • Use of concrete reef balls as a substrate used in the river. They typically attract fish as soon as they placed in water. • Creating oyster habitat by placing mesh bags full of oyster shells underneath their docks. Concrete reef balls which were substrate used in the river. They attract fishes once placed in water. Volunteers create oyster habitat by placing mesh bags full of oyster shells underneath their docks. An experiment using light sensors such as these is now being used to scientifically determine how extensively oyster reefs affect water clarity.
- 27. Key Benefits: • These experiments are being used to look at how oysters provide ecosystem services by clearing water as they feed on microscopic plants. • Improves water quality and providing essential fish habitat. Precedents Locations of oyster beds Loxahatchee River, Florida
- 28. Sapelo Island, Georgia Precedents Sapelo Island is a state-protected barrier island located in McIntosh County, Georgia. The island is only accessible by airplane or boat, with the primary ferry coming from the Sapelo Island Visitors Center in McIntosh County, Georgia, a seven mile (11 km), trip. The 16,500-acre island is Georgia's fourth largest and, excepting the 434-acre African American community of Hog Hammock, is entirely state owned and managed.
- 29. Precedents Sapelo Island, Georgia Threats: • Due to the high energy wave activity, rise in sea levels and incompatible development leave coastal lands vulnerable to erosion and loss of habitat. Hardened structures have been used on the shorelines but instead they reflect wave action into the water causing more damage. • A tangle of salt marsh and sand reachable only by boat, holds the largest community of people who identify themselves as saltwater Geechees. 1 2 3
- 30. Strategy: Using two(2) distinct methods, the Conservancy is helping to create oyster reefs along the tidal creeks as a sustainable, natural alternative to harden the shorelines. Precedents Sapelo Island, Georgia Use of layered mesh bags containing about 8,000 bushels of oyster shells as a technique for attracting oyster larvae to attach and form reefs. Oyster reefs stabilizing the soil
- 31. Precedents Key Benefits: • Minimizes erosion • Absorbs impact of boat activity • Enhances habitats for residents and visitors (fishes, seabirds and invertebrates) • Improves water quality • Increase of salt marshes Chained-like steel baskets containing rocks are being used at another test site to determine which is best material used for attracting larvae and supporting reef growth. Bagging the recycled oyster shells to plant native vegetation behind the sites to stabilize the soil and enhance the habitat. Sapelo Island, Georgia
- 32. Precedents Jeremy Creek, South Carolina Jeremy creek is located in McClellanville, South Carolina. Piloting a larger boat is a crapshoot at lower tides in Breach Inlet, Jeremy Creek and the channel through Cape Romain. McClellanville is a small fishing town in Charleston County. McClellanville has a total area of 2.4 square miles (6.1 km2), of which 2.2 square miles (5.8 km2) is land and 0.1 square miles (0.3 km2), or 5.02%, is water. Jeremy Creek, a tidal inlet, runs through the center of the town, and the town limits extend south to the Intercoastal waterway, adjacent to Cape Romain National Wildlife Refuge.
- 33. Precedents Jeremy Creek, South Carolina Thursday 3 December 2:42 AM EST Last Quarter 7:04 AM EST Sunrise 7:40 AM EST 0.30 m (0.99 feet) Low Tide 12:46 PM EST Moonset 2:08 PM EST 1.47 m (4.82 feet) High Tide 5:10 PM EST Sunset 8:13 PM EST 0.27 m (0.88 feet) Low Tide Friday 4 December 12:48 AM EST Moonrise 2:51 AM EST 1.40 m (4.59 feet) High Tide 7:05 AM EST Sunrise 8:37 AM EST 0.33 m (1.07 feet) Low Tide 1:19 PM EST Moonset 2:59 PM EST 1.43 m (4.69 feet) High Tide 5:10 PM EST Sunset 9:05 PM EST 0.25 m (0.83 feet) Low Tide Saturday 5 December 1:41 AM EST Moonrise 3:43 AM EST 1.43 m (4.70 feet) High Tide 7:05 AM EST Sunrise 9:34 AM EST 0.31 m (1.03 feet) Low Tide 1:50 PM EST Moonset 3:50 PM EST 1.41 m (4.62 feet) High Tide 5:10 PM EST Sunset 9:56 PM EST 0.22 m (0.72 feet) Low Tide MCCLELLANVILLE, JEREMY CREEK TIDE TABLE:
- 34. Precedents Jeremy Creek, South Carolina Threats • Oyster reefs are in severe decline along the Atlantic seaboard due to overharvesting of oysters, boat activity, habitat loss and pollution. • Rise in sea-level is also causing increase in erosion along South Carolina’s beaches and marshes. The sea level rise stands to make things much in the Canal City, and a global warming awareness group is using data from new papers and a unique approach to help spread awareness of the risks tied with sea level rise.
- 35. Precedents Jeremy Creek, South Carolina Strategy • The Conservancy aided to restore oyster reefs in the Cape Romaine National Wildlife Refuge with 24 oyster castles, structures made with interlocking blocks composed of concrete, limestone, shells and silica. • The castles were strategically placed in locations where oyster reef growth would help slow erosion. Oyster castles were used along Jeremy Island after proving effective on the Virginia coast. 24 oyster castles, each made with 13 interlocking blocks, were placed along the shoreline of Jeremy Island Oyster castles, made of 30-pound blocks of shell, limestone and cement, provide a surface for oyster larvae to attach and form reefs Close-up of reef growth after 6 months following the launch of the project
- 36. Precedents Cycle of flow Key Benefits • Slow erosion and protects the shorelines • Enhance habitats for oysters, fishes, crabs and other marine lives • Filters impurities from coastal waters.
- 37. Tibwin Creek, South Carolina Precedents Tibwin Creek is a stream located just 6.5 miles from Awendaw, in Charleston County, in the state of South Carolina, United States. The district encompasses 105 contributing buildings in the town of McClellanville. They include residential, commercial, religious and educational building dating between about 1860 to 1935. Architectural styles include: Carpenter Gothic, Queen Anne, and Italianate. Notable buildings include the King Brothers Store, McClellanville Public School, New Wappetaw Presbyterian Church, Bank of McClellanville, McClellanville Methodist Episcopal Church, and a number of dwellings originally built as summer homes by St. James Santee and Georgetown planters. Tibwin Plantation
- 38. Precedents Threats: • The driving forces behind the decline of oyster reefs include destructive fishing practices, coastal over-development and effects from upstream activities such as altered river flows, dams, poorly managed agriculture and decline of water quality. • The Nature Conservancy released the first-ever comprehensive global report on the state of shellfish at the International Marine Conservation Congress in Washington, DC. The report concludes that oyster reefs are the most severely impacted marine habitat on the planet. Tibwin Creek, South Carolina
- 39. Precedents Key Benefits: • Improves water quality • Absorbs impact of storm surges • Provides habitats for residents and visitors (fishes, seabirds and invertebrates) • Slows erosion from rise in sea-level Volunteers help to fill and install mesh bags of recycled oyster shells along the restoration site The Conservancy has helped to establish 25sqm of reef in Tibwin Creek using mesh bags of oysters, a technique that has proven successful. Strategy: • Creating an oyster reef in Tibwin Creek using mesh bags of oyster shells layered on untreated wood pallets. • The new reef covers 25sqm, connecting 2 existing natural reefs.
- 40. Pamlico Sound, North Carolina Precedents Pamlico Sound in North Carolina in the US is the largest lagoon along the North American East coast, extending 129 km (80 mi) long and 24 to 48 km (15 to 20 miles) wide. It is part of a large, interconnected network of lagoon estuaries that includes Albemarle Sound, Currituck Sound, Croatan Sound, Pamlico Sound, Bogue Sound, Core Sound, and Roanoke Sound.
- 41. Precedents Threats: • Overharvesting, decline of water quality, disease and habitat loss has reduced the distribution of oysters in past history. • Every time it rains around the Albemarle-Pamlico watershed, water erodes the land. The precious soil which washes away into streams is called sediment. Sediments are carried downstream and may eventually enter the Sounds, where they settle out of the water and cover the bottom. • Wetlands, one of the most important types of habitat, are threatened all around the Albemarle-Pamlico watershed. They are filled in for development, drained for agriculture, or dredged for marinas. Pollution has degraded water quality in the Sounds and their rivers, resulting in declines of important SAX and scallops. Pamlico Sound, North Carolina
- 42. Precedents Strategy: Using lime stone marl (basket-ball sized fossil rock) distributed via barge, 64.5 acres of 3-dimensional reefs were constructed. Key Benefits: • Broodstock for adjacent natural reefs • Developing increase in flexibility to diseases • Enhance habitat for oysters, fish and other marine animals • Improving the water quality Crane dumps fossil rock into state protected waters in Pamlico sound, providing a surface for oyster larvae to attach and grow. Along with the marl, netted bags of recycled oyster shells were placed in Pamlico Sound to help grow more reefs.
- 43. OYSTER APPLICATION IN FORMBY
- 44. Future considerations for UK Closed Loop Urban projects Shifting Shores – living with a changing coastline Fast-forward to this past winter and a succession of violent storms and extreme tides saw the erosion and flooding thinking this could happen over the next 5 to 15 years occurring overnight. Increasingly, ‘defence’ as the only response looks implausible. Instead we must adapt and take the longer view. Future forecasts say climate change will lead to sea level rise and increased storminess which will, in turn accelerate the scale and pace of coastal change.
- 45. Application of Oyster technique in Formby Formby Coast The Sefton coast is the largest dune area in England. It extends over 35.5km and comprises soft and granular estuary deposits of sand, silt, clay and peat. The dune coast extends for 17km in length, and between a few hundred metres and 4km in width. Erosion/accretion pattern along the Sefton coast is very similar both with and without storm clustering effect. However, the morphological changes in the ridge-runnel system are more pronounced when storms occur in isolation, especially when beach gradient is gentler. At Formby the mobile dunes are migrating landwards in response to coastal erosion. Beaches, intertidal habitats and dune systems can provide a natural and cost- effective means of flood defence. Formby coastal changes-timeline and future changes 1906 1945 2005 2045 2105 The dunes most seaward extent occurs at Formby Point just to the north of the River Alt discharge
- 46. Erosion in Formby Application of Oyster technique in Formby Formby is faced with the challenge of erosion along the shoreline from the influence of the wind, water and human activity, the shoreline is constantly changing. For example, extensive erosion at Formby Point during the eighteenth century was reversed in the mid-nineteenth century, when it gained 300m around its whole arc.
- 47. Storm event Hs (m) Tp (s) Wave Dir. (°) Wind Speed(m/s) Water level(m) Storm power(m2/h) Max. WL during storm D1 4.6 9.3 281 20 5.0 266 5.1 D2 2.8 8.1 276 14 1.3 110 3.6 D3 3.8 7.7 264 15 0.5 185 3.2 J1 2.6 6.7 276 15 4.2 15 4.4 J2 2.9 7.5 287 15 2.4 52 2.8 J3 3.7 7.6 287 17 2.4 83 2.6 J4 3.0 7.6 281 14 2.7 82 2.8 Storm events that occurred in December (D1, D2, D3) and January (J1, J2, J3, J4), storm duration, temporal storm spacing, and characteristics at peak storm wave height and storm power index. Application of Oyster technique in Formby Storm impacts
- 48. Application of Oyster technique in Formby Wind directions Storm impacts
- 49. • Creating artificial tidal creeks along the coast and thereby creating other marine habitats • Creating oyster mats and placing them in the creeks and also along the coast to grow oyster reefs Application of Oyster technique in Formby Proposed Strategy Creek Section Marshlands are terraced for tourists to have a beautiful view of the tidal creek and the oysters
- 50. Oyster processing F R M YB
- 51. Conclusion In order to maintain a stable shoreline, harvesting of oysters in Formby coast should be at moderate. RECYCLING oyster shells REDUCING the effects of erosion and overharvesting of oysters REUSING oyster shells Key Benefits: • It hardens the shoreline • Minimizes the effects of erosion and flooding • Enhance habitat for oysters, fish and other marine animals • Improving the water quality • Enables creation of oyster industry