ClassX Video Lessons Youtube Channel Curiosity Stream Can We Save Venice From Flooding? | Bright Now
On October 28th, 2018, images of Venice submerged under high tides captured global attention. While Venetians are no strangers to flooding, the intensity of this event was unexpected. It had been a decade since tides surpassed 1.5 meters above sea level, and on that day, 75% of the city was underwater. Traditional measures like walkways, pumps, and barriers proved inadequate, leaving residents and tourists alike navigating the city with waterlogged feet.
To combat such flooding, Venice has turned to an ambitious solution known as MOSE (Modulo Sperimentale Elettromeccanico). This project involves a series of 78 massive flap gates, each weighing nearly 330 tons, positioned at the lagoon’s four entrances. These gates lie on the seafloor and, when needed, are filled with air to rise and block incoming tides.
MOSE represents one of the most complex hydraulic engineering feats ever attempted. The construction involved assembling a concrete platform on the seafloor, composed of individual units called “caissons.” These caissons, resembling four-story buildings, are meticulously crafted to withstand the corrosive saltwater environment. Each weighs 24,000 tons and is transported using specialized trolleys equipped with pistons.
The caissons are carefully towed by tugboats to their designated locations, where they are gently lowered onto prepared ballast. Precise alignment is crucial to ensure a watertight seal between each caisson. The platform also features an underwater tunnel, allowing technicians to access and maintain the flap gates’ hinges.
With the platform in place, the installation of the flap gates begins. The process is intricate, involving divers who prepare the slots for the hinges. The gates are lowered gradually, with video cameras capturing the critical moments as technicians make fine adjustments to ensure perfect alignment. The hinges are vital, as they house all electronic connections to the gates.
Once the gates are secured, technicians in the sea tunnel rotate and lock them into position, ensuring a watertight fit. With all 19 gates installed, the MOSE project moves to the next phase. A specialized jack-up vessel, resembling a giant grasshopper, assists in the installation of the remaining gates. This vessel can rotate 360 degrees with precision, stabilizing itself using hydraulic jacks.
By the end of the year, all mobile barriers are expected to be in place. Initial tests have begun, but it will take months of fine-tuning before MOSE is fully operational. Only then will we know if this monumental engineering effort can preserve Venice’s historic beauty from the threat of rising tides.
Conduct a detailed research on the MOSE project, focusing on its engineering aspects, challenges, and current status. Prepare a presentation to share your findings with the class, highlighting how this project aims to protect Venice from flooding.
Create a simple simulation or model to demonstrate how the flap gates of the MOSE project operate. Use materials like cardboard, plastic, or software tools to illustrate the process of the gates rising and blocking tides. Present your model to the class and explain the mechanics involved.
Participate in a debate on the environmental impact of the MOSE project. Divide into two groups, with one supporting the project as a necessary measure to save Venice, and the other opposing it due to potential ecological consequences. Use evidence from research to support your arguments.
Analyze a case study of another city facing similar flooding challenges. Compare and contrast their solutions with the MOSE project. Discuss in groups how these solutions could be adapted or improved for Venice, considering technological and environmental factors.
Draft a proposal for a field trip to Venice to study the MOSE project firsthand. Include objectives, expected learning outcomes, and activities that would enhance understanding of hydraulic engineering and flood prevention strategies. Present your proposal to the class for feedback.
**Sanitized Transcript:**
[Applause] On October 28th, 2018, pictures of the high tide in Venice went viral around the world. This is nothing new for the Venetians, who are accustomed to it, but the intensity caught everyone off guard. It had been 10 years since a high tide had exceeded the threshold of 1.5 meters above sea level. On October 28th at 2 p.m., 75% of the city was underwater. The usual solutions, such as walkways, pumps, and barriers, were not enough this time. Inevitably, restaurant-goers were forced to eat their pizza with their feet in the standing water.
Only a system of floodgates at the four lagoon entrances can protect the city from flooding. This solution, called MO, is based on an idea that is as simple as it is innovative. It consists of 78 flap gates that each weigh nearly 330 tons and will lie at the bottom of the lagoon. When needed, the flap gates will be pumped with air until they rise in a straight line, blocking the flow of the tide coming in.
Despite its simplicity, MO is the most ambitious and complex hydraulic engineering project ever attempted in the world. It took years to assemble the concrete platform on the seafloor. The individual components that make up the platform have been built on the mainland. The engineers call them “caissons.” They may look like simple four-story buildings under construction, but each and every detail is special. From the concrete to the steel, all elements must endure the saltwater. Each caisson weighs 24,000 tons and requires a special trolley fitted with pistons capable of raising them gently and moving them to the launch pontoon.
Once it’s semi-submerged, like an iceberg, the caisson is dragged by tugboats until it reaches its final home. This is the most delicate phase; the caisson needs to be lowered slowly until it rests on the ballast that’s been prepared for it on the seafloor. It needs to be aligned with the previous one in such a way that the trimming between one caisson and the next is completely watertight. The platform has been designed to contain an underwater tunnel that crosses the entire stretch of sea. Here, technicians can go down and fix the hinges of the flap gates.
Back on the surface, the flap gate is now ready to be installed. [Music] It’s time for the last flap gate of this inlet to be mounted, but the operation on number 19 gets off to a challenging start. The divers swim underwater to prepare the slots that will host the hinges. Now for the most sensitive phase of the descent: the hooking of the hinges.
The cables gradually lower the flap gate, allowing the hinges to perfectly slide into the fitted slots. Video cameras film the decisive moment. The technicians have to constantly make small adjustments to compensate for all external interference. The technicians know the hinges are the heart of the system; all electronic connections with the flap gate pass through them.
It’s touchdown—so far, so good, but it’s not over yet. The technicians in the sea tunnel must now complete the hooking by rotating it 90° and securing it to the platform. A message arrives from underwater: it’s perfectly watertight. Operation over. [Applause] All 19 flap gates are in place.
To assist in the installation of the rest of the high water protection gates is MO’s jack-up vessel. It’s basically a floating barge resembling a grasshopper. Its special design allows it to connect and lift the flap gates directly from the pier. The jack-up has four independent engines, allowing it to easily rotate 360° with absolute precision and even stay in place without the use of anchors.
Once the jack-up reaches its position, the onboard computers neutralize the currents to keep it stable, even as large ships pass through the waterway. [Music] A system of hydraulic jacks raises the barge above the water to stabilize the vessel. Hanging from four steel cables, the technicians lower the flap gate to the platform below.
By the end of the year, all mobile barriers are scheduled to be in place. The first tests on those already installed have started, but it’ll take months of tuning and testing before MO is operative. Only then will the world discover if this colossal mega structure can save Venice and its ancient beauty. [Music]
Flooding – The overflow of water onto land that is normally dry, often caused by heavy rain, storm surges, or melting snow, and can lead to significant environmental and structural damage. – The engineering team developed a comprehensive plan to mitigate flooding in the coastal city by enhancing the drainage systems and constructing levees.
Tides – The regular rise and fall of sea levels caused by the gravitational forces exerted by the moon and the sun, which can impact coastal engineering projects. – Understanding the local tides is crucial for engineers when designing structures like bridges and docks to ensure they withstand varying water levels.
Project – A planned set of tasks and activities undertaken to achieve specific objectives, often involving research, design, and construction in engineering and environmental studies. – The university’s environmental engineering department launched a project to develop sustainable water management practices in urban areas.
Engineering – The application of scientific and mathematical principles to design, build, and maintain structures, machines, and systems, often with a focus on solving practical problems. – Civil engineering students are working on a project to design a new pedestrian bridge that minimizes environmental impact.
Hydraulic – Relating to the use of liquid, typically water, to transmit force or energy, often used in the context of machinery and systems in engineering. – The hydraulic system in the dam was upgraded to improve efficiency and ensure better control of water flow during peak seasons.
Installation – The process of setting up equipment, machinery, or systems for use, often requiring technical expertise in engineering fields. – The installation of solar panels on the university campus was completed by the engineering students as part of their renewable energy project.
Caissons – Watertight structures used in underwater construction to provide a dry working environment, commonly used in bridge and pier foundations. – The construction team used caissons to build the foundation of the new bridge, ensuring stability and safety in the riverbed.
Barriers – Structures or obstacles designed to prevent or control the movement of water, people, or vehicles, often used in environmental and civil engineering projects. – Engineers designed flood barriers to protect the coastal town from storm surges and rising sea levels.
Environment – The natural world or ecosystem, including air, water, and land, which can be affected by human activities and engineering projects. – Environmental engineers work to develop solutions that minimize the impact of industrial activities on the environment.
Protection – Measures and strategies implemented to safeguard natural resources, structures, or populations from harm or damage, often a key consideration in environmental and engineering projects. – The new regulations focus on the protection of wetlands, requiring engineers to consider ecological impacts in their project designs.
