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Floating cities

June 6, 2024 By EarthWise Leave a Comment

About 40% of the world‘s population lives in coastal regions. People really like ocean-front property. But worldwide, rising sea levels mean that more and more people want to live on land that may someday be swallowed up by the sea.

One possible solution to the problem is to build cities on top of the water. It sounds pretty futuristic and impractical, but it is starting to happen. There have long been floating communities in places like the Netherlands, but these are for the most part clusters of houseboats moored close together.

But there are far more ambitious projects underway. The Maldives Floating City, already under construction, will eventually have 5,000 houses located in a lagoon that is a 15-minute boat ride from the capital city of Male. The housing units will be tethered to the lagoon floor and linked together.

A new project, located off Busan, South Korea, will combine high and low technology to create a large-scale, on-water town, that can house more than 10,000 people.

The town will be built on enormous concrete platforms suspended on the water. The platforms float because they are rounded hexagonal boxes that are buoyed up by Archimedes’’ principle. They can’t sink. Such structures will attract marine life, providing places for oysters and mussels, for example, to grow.

The initial development will cover 15 acres and the infrastructure will handle power, water, waste, and even some food. The goal is even to produce enough energy to provide some to the nearby community. A bridge will link the community to the land.

The project is scheduled to be completed in 2028. Future expansion could end up housing 150,000 people.

Floating cities could soon no longer be exotic or futuristic.

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Web Links

Are Floating Cities the Solution to Rising Seas?

Photo, posted June 5, 2012, courtesy of Raymond Bucko via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

History Emerges In European Drought | Earth Wise

October 17, 2022 By EarthWise Leave a Comment

During the summer, much of Europe faced a string of extreme heat waves and a devastating drought. As a result, many reservoirs and rivers have shrunk back to reveal historical structures and relics that, in some cases, date back thousands of years. Once-submerged villages, ships, and bridges have re-emerged this year.

In northwest Spain, a former village called Aceredo has reappeared after having been submerged 30 years ago when a hydropower dam flooded the valley where it was located. Elsewhere in Spain, the Dolmen of Guadalperal, a 4000-5000-year-old stone monument often called the Spanish Stonehedge, has risen from a drought-stricken dam west of Madrid

In Italy, which is suffering from its worst drought in 70 years, the ruins of a bridge from the time of Nero are now visible in the Tiber River. One of Germany’s largest reservoirs, the Edersee, has shrunk back so much that parts of Berich, a village that was flooded in 1914, can be seen. In Serbia, water levels in the Danube River are so low that more than a dozen sunken Nazi boats from World War II have been exposed in the town of Prahovo. In Northern England, the lower water levels of the Batings Reservoir have uncovered an ancient packhorse bridge.

The shrinking of riverbeds and reservoirs across Europe has attracted a great deal of attention, probably more than many other effects of the increasing number of extreme weather events because it is so visual. But the frequency of extreme heat and drought is only likely to increase over time.

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Web Links

Europe’s Shrinking Waterways Reveal Treasures, and Experts Are Worried

Photo, posted July 13, 2017, courtesy of Marco Brandstetter via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Wildlife Bridges

June 17, 2019 By EarthWise Leave a Comment

Highway accidents involving animals are a big problem for both people and animals. About 200 people die every year in the U.S. as a result of collisions with animals. In total, one to two million large animals are killed by motorists every year. And these crashes are expensive: deer-car collisions cost an average of more than $8,000 each; elk-vehicle collisions about $25,000; and moose-vehicle collisions over $44,000.

In the United States, there are 21 threatened and endangered species whose very survival is threatened by road mortalities. These include Key deer in Florida, bighorn sheep in California, and red-bellied turtles in Alabama.

One solution that has been quite effective around the world in reducing car-animal collisions is wildlife overpasses and underpasses. Crossings and fencing that guide animals over or under highways reduce collisions by 85-95%.

These traffic-spanning bridges and tunnels have been popular in Europe since the 1950s. The overpasses usually look much like regular overpasses for cars but are decked out with native flora. The underpasses, which assist shyer and smaller animals, are typically invisible to drivers.

Washington State has recently started building wildlife bridges and underpasses on Interstate 90. These passes will allow elk, black bears, mountain lions, pika, and even trout to traverse what was once a near-impenetrable barrier of road.

Some animals that are accustomed to human structures start using the crossings almost immediately. For others, there is learning curve. As in many things, the early adapters are important as they provide paths and model behavior that more reticent animals learn to follow.

Wildlife bridges are a very good thing for wildlife and for people.

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Web Links

How wildlife bridges over highways make animals—and people—safer

Photo, posted July 22, 2017, courtesy of David Fulmer via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.