It feels like the end of the world here. There are no more markers, pylons or charts to guide us through the channels.
Occasionally you'll see the white dot of a seabird nesting in the distance but, apart from that, nothing. I never imagined this was here - and if I hadn't stood in the Piazza San Marco that morning I never would have believed this was Venice.
"Venice is the product of a thousand years of modifications of the environment," says Luca Zaggia, a coastal oceanographer and marine geologist who has worked in Venice for 20 years at the Institute of Marine Sciences. Luca is leading our Secrets and Science of the Lagoon tour, a four-hour expedition into the outer lagoon.
I'd been apprehensive about spending the day with a marine scientist, fearful that most of what he said would go over my head. However, when Luca greets us, he does so with two shopping bags of sausage, cheese and wine and I'm instantly at ease.
As we board our bragazzo, a traditional Venetian boat, and head into the Castello neighbourhood, Luca answers my first question: is Venice sinking or is the sea rising? The answer is both. The daily consumption of water in Venice is 200 litres a person - 20 times that of a hundred years ago. Along with water used by the nearby industrial area of Porto Marghera, this sucks up the groundwater from underneath the city.
Luca explains that the mud and sediment underneath Venice's foundations are like a sponge. The less moisture and pressure there is in the sediment, the more the sponge will dry and contract, pulling the city down. There is also the global problem of sea levels rising.
Once we're out in the lagoon, we begin to glimpse a different Venice. It's Saturday morning and it's surprisingly busy, with dozens of teams practising Venetian rowing, fishermen with small dogs, families with picnics, people with groceries and not a gondola to be seen.
Unfurling a large map and placing it on the bottom of our boat, Luca points out the islands of the lagoon.
The Grand Canal, the tourism epicentre of Venice, forms only a tiny part of the lagoon. We see Murano, where Venetian glass is made; the Lido, where you lie on the beach; Sant'Erasmo, where produce is grown; and our destination, Torcello, a sleepy little island at the other end of the lagoon.
Luca also points out the natural salt marshes around us. The marshes closest to the city are surrounded by small pontoons, which protect them from the wash of motor boats. Between the 1930s and '70s, Venice lost 50 per cent of its salt marshes to the wash of motor craft, rising sea levels and storm waves.
High waves created by cargo ships on the way to the mainland port of Mestre also swamp the marshes. The sustainability of the marshes is just one of many environmental challenges Venice faces.
We enter a back inlet on the island of Torcello. Archaeological evidence found near here indicates there was human habitation in the lagoon more than 1500 years ago.
The island was once an outpost of the Byzantine Empire and home to more than 10,000 people. Now, there are a few dozen inhabitants. We pull up near some floating cages over which two fishermen are bending.
Luca asks in Italian what they are fishing for. They answer in Venetian: moeche - small shell crabs found in the lagoon. It is news that excites our captain and Luca.
"This is the best possible thing you can eat in Venice: moeche," Luca says. "The best time to eat it is when they moult their shells in spring. When you take your winter coat off it's time to eat."
Later, we make a point to find moeche and eat it and it is as good as Luca promised.
Fishing is essential to Venetian life but the battle between tourist dollar and tradition rages. Back in Venice, Luca says, a protest is being held against the proposed relocation of the fish markets to the mainland to make way for a cruise terminal extension.
Next, Luca offers us the option of heading into the remote northern lagoon to a place called Bone Island, or Sant'Ariano.
Originally a monastery, the island became an ossuary for dumping bones during the 16th century as the Black Death hit; first in 1575 and again in 1630, when Venice lost a quarter of its population to the plague.
"Most Venetians won't go there as it is haunted or bad luck - but I'm not Venetian," Luca smiles. It's a place so little visited even the landing jetty has rotted away and I leap from the boat to get to the shore. It is overgrown with thorny brambles and I can only stand at the gates of the small chapel built to commemorate the dead, unable to pass inside.
We loiter on the shore for a few minutes. Among the debris are archaeological relics: pieces of earthenware plates and a small fragment of terracotta tile, the fingermarks of the worker that shaped and smoothed it still visible; shattered pieces of history in the palm of my hand.
We head back towards the mouth of the lagoon, dropping anchor on a sandbar, a place locals call the Bacan. During summer, locals bring their boats here and drop anchor to swim in the clean, cool water and to escape the crowds at the Lido.
There is only 30 centimetres of water below us and I can see tiny fish in the seagrass. These shallow sandbanks were Venice's key defence, Luca says, slicing up two plates of salami and cheese.
Only Venetian sailors knew how to navigate the channel and attackers would often run aground on the sandbar, becoming easy targets for the once mighty Venetian Republic.
We're also in full view of the MOSE barrier. An ongoing, unfinished 30-year project, the MOSE barrier is designed to act like an underwater drawbridge, rising from the bedrock during the tide peaks and storm surges that frequently flood Venice.
Luca passes us plastic cups of local red wine and shows us a laminated image of what the completed barriers will look like. Not everyone is pleased with the aesthetics, he says, but waterlogged beggars can't be choosers. In theory, once the barrier goes up it will stop Venice flooding. However, it will also impede the natural cycle of the lagoon.
"The water here can be as hot as 30 degrees in summer, even more sometimes. With these temperatures, algae and bacteria grow fast and it becomes like soup."
For tourists, this means Venice may get more smelly but there are dire consequences for the environment, with a lack of oxygen in the water possibly killing fish and plant life. It's these issues that make the MOSE barrier so controversial. However, sitting on a Venetian bragazzo with a glass of wine and a plate of cheese under a perfect blue sky, it's easy to see why it has taken so long for the project to find its legs. When debating the pros and cons of the project is so enjoyable, why would you want to rush?
Author: Shaney Hudson | Source: Stuff Co./NZ [July 28, 2011]