PROJECT STATEMENT
Impacted by the global sea level rising, the study area, the Venetian Lagoon, is in Venice, Italy, a region with magnificent civil tourism resource, is vulnerable to regular flood caused by high tide and over-tourism as well. Based on the current topographic and cutting-edge artificial island strategy, the proposal is to integrate coastal resilience and facilities to create flood adaptive landscape for the next 100 years. It takes several decades to establish three artificial islands, of which the process is similar but the functions will meet the needs respectively. The proposal includes three phases:
a.) Protect the Venetian Lagoon and inland from being inundated caused by high tide and increasing sea level.
b.) Reclaim the artificial islands with planting materials succession from shoreline to inland.
c.) Develop functional facilities to create more attractive spots to mitigate the tourism pressure on Venice Island and provide additional revenue resource to implement next stage of proposal.
PROJECT NARRATIVE
BACKGROUND
Venice Island, located on Venetian Lagoon, Italy is a global attraction with rich history, magnificent architecture and city configuration, practical construction technique and a beautiful shoreline. However, it is the perfect island that keeps losing local population and this trend seems unstoppable.
FACTORS
From the early 20 century, people kept moving in because of the booming industry and tourism. It peaked at around 1968 (240,000) but went down dramatically since tourists became dominant on the island (National Institute of Statistics (Italy), 2014). By comparison, the number of tourists increased yearly significantly, from 400,000 to 20 million nowadays. Some residents participated in protest, decrying tourists while many of them made a hard decision to move out from estuary and Venice Island to mainland. In addition, the AirBnBs mostly hold by foreign investor spread out many islands, from Venezia, Giudecca to Murano, going up to 8,500 units, most of which were residential accommodation previously. With 7 districts of main islands, there are 676 units in Dorsoduro, 577 units in Santa Croce, 1648 units in Cannaregio, 1730 units in Castello, 614 units in San Polo, 963 units in San Marco and 208 units on Giudecca (Inside Airbnb, 2019). The number of Airbnb units on main islands is as 25 times dense as the number on mainland. The high density of tourist accommodation brings even more awkward. The bridges and canals, regarded as transport system, are mostly occupied by tourists with cameras, gondola with tourists and busy restaurants or souvenir shops. Another important factor is the natural condition. The MOSE project, which is a physical barrier to prevent the rising sea level and high tide which is higher than 1.4 m. The daily tide, normal lower than this level, but higher than 0.8 m has the possibility to cause an annoying inundation, affecting the life quality and construction base on island (The Flooding of Venice: What Tourists Need to Know, 2019). The frequency of the affecting high tide is around 110 times per year (Venice water tide booklet (2019), 13-14). And the mean sea level is predicted to be 0.2m, 0.4m and 2 m higher than current situation by 2030, 2050 and 2100 (From Global to Regional, 2010). In the meanwhile, the tourists will yearly bring 1 billion Euro based on the regulations and tourist numbers, ranging from 3 to 10 Euros (Venice to begin imposing tourist tax on day-trippers (2019, Oct 10)), which can be a revenue source to implement proposal to mitigate the over-tourism and inundation.
STRATEGY
Fortunately, China is making use of the cutting-edge technique to reclaim artificial islands with high efficiency, costing approximately 1,800 Euros/m2 which has the possibility to support a 137 acre reclaimed area (How to build up an artificial island, Paper Clip, (2019, Aug 21)). The proposal for Venetian Lagoon will mainly have three processes: protect, reclaim and develop. First, protecting the Venetian Lagoon and inland from being inundated caused by high tide and increasing sea level by building up an artificial island with four processes: boundary setup, sediment fill-in, basement compaction and embankment setup. The second step is to reclaim the artificial islands with planting materials succession from shoreline to inland. Lastly, developing functional facilities to create more attractive spots to mitigate the tourism pressure on Venice Island and provide additional revenue resource to implement next stage of proposal.
PHASING
Since the proposal is based on the high tide and sea level rising for 2030, 2050 and 2100, there will be three separate reclaimed lands established by year changing. We will start with the revenue from tourists on Venice Island to achieve phase 1 by 2030. And plus the income from new developed areas can also be collected and support phase 2 by 2050. The same mechanism works for phase 3 by 2100. This working mechanism is not only for Venice, Italy, but also works for any coastal city with potential developed resource when facing predicted natural issues. A set of suitability maps can help us to figure out the ideal locations where the bathymetry is around -2 m and the slope is less than 2% to start proposal. Functional districts The reclaimed areas can be defined as Eco-tourism district, Entertainment tourism district and Company community district. Even though new attractive spots are developed, a natural buffer will separate the tourists and resident areas and tourists will still have good view to Adriatic Sea.
PERFORMANCE
By 2030, a frequency of 110 times/ year high tide can be prevented. The developed area can block the high tide plus rising sea level up to 2m and the potential population of local residents can increase to 310,000 by 2050. In the last phase, the Venetian Lagoon can resist a flood up to 3.4m and the density of tourists can decrease to 14/ acre (with construction occupied) which is half the previous rate. Even if a super high tide occurs, the canals between new reclaimed lands can work as polders to collect the overflow.
