Posted March 12, 2020
HOLDEN, Mass. – We were standing on the banks of the Mississippi River, about an hour west of Boston.
Of course, the real Mississippi River is halfway across the continent. We were in fact in the huge warehouse-sized laboratories above the Louisiana River Basin Scale, which was shocking to restore the scale to 1/65, right down to the modeled sand.
The model is one of the brightest parts of the ambitious reconstruction project The Louisiana coast is disappearingwhich is rapidly disappearing from the rising and sinking seas. Engine experts want to be sure that their river diversion design work will be done with a huge mechanism to restore degraded water basins.
A diversion is a series of gates located at the riverbank that can be opened and closed. Runaway river water is likely to dump sand, sediment and clay into nearby pools that have been destroyed by climate change and other environmental disasters.
The model, which costs about $ 4 million to build and test, is a bargain, says Dan Gessler, who builds the Alden Research Laboratory. “You basically pay for insurance to make sure you get it right,” he said. Given the cost of the completed project, approximately $ 1.4 billion, and the enormous costs of correcting the design flaws that the working model may reveal, “It is very, very cheap.”
It’s also fun. On a model scale I would be over 300 feet tall, a hard experience for a short person. Dr. Gessler was walking on a bridge that would put him in the middle of the river and splash a stream of bright red paint into the water to watch the streams flow.
In the middle of the river there is a deep navigation channel, which serves as the main freight route. The dyes continue to flow inward, while the subversive dye obediently flows through the long clasp that would, in real life, then enter a sprawling mosaic of rivers and rivers in southern New Orleans known as Barataria. The paint experience shows that navigational vessels are not likely to be diverted.
Since the 1930s, Louisiana has lost more than 2,000 square miles of Delaware’s size due to falling, rising sea levels and the loss of sediments along the Mississippi River. These levers have reduced floods for decades and saved endless lives, but they have also accumulated the nutrient residues that previously flowed through spring floods and renewed Delta. That and other damage to wetlands, including cut-offs for oil and gas exploration, resulted in sustained losses of football around the roof every 100 minutes.
In response, the state developed a $ 50 billion, 50-year master plan for coastal restoration and protection. The first one was released in 2007, and Louisiana has since revised and updated its plans every five years.
Officials have developed an ambitious list of projects to protect state territories and restore wetlands, which could spur the effects of hurricanes. But the planners realized that they could not recover all the land lost for decades and had to strategize on which areas could be protected and how.
The Mid-Barataria diversion and a similar structure to the north that opens to another body of water to the east are among the most expensive, daring and promising offerings. Soil can be built by sliding and sump pumping, and Louisiana has done some of that in some areas, including efforts to plunder state-owned islands.
But the process is extremely expensive. The Medieval Bariatry subversive can rebuild 60 square miles in its first 50 years, says coastal authorities, by building land in critical areas where people live, work and play.
Funding for the diversion is obtained from billing amounts received from BP in 2010 Deepwater Horizon Spill:.
Coastal Protection and Recovery Authority And for the project, the project manager said that diversions are nothing short of revolutionary for those who run a powerful water pipe. For more than 100 years, flood protection has been a priority, far beyond the health of wetlands.
Building a diversion means opening those levers, “a complete understanding of how we use the lower sources of the Mississippi River,” he said. Subversion is sure that “we can no longer do things by protecting things from the flood.”
When constructing the model, the designers try to monitor the water flow, pressure and flow around the structure and find out how much sand is projected to be expected to reach its long crack. Other constituents of the soil, sludge and clay, are suspended in sufficiently uniform water and discharged with electricity.
But the sand is heavier. Thus, the engineers needed to check the conditions for raising the sand and move it into the reservoir by pouring a minimum amount of fresh water into the enclosures and bays.
The ladder model, about 200 feet long and 70 feet wide, had to take into account the differences between the actual river flow rate and the actual model sand weight.Researchers need sand for their model with specific dimensions and density to match real behavior.
Answer: “We had to reach for false sand,” said Dr. Gessler. They designed standard standard equipment and produced a plastics company. White acrylic with sugar stability, ordered in huge quantities and worth about a thousand dollars per ton.
As the 200,000 lb of recycled water flows through the model, researchers are feeling unexpected in real time.
Dr. Gessler pointed to a place, at the bottom of the ramp, where water flows into the wall of the channel and, as he says, “squeezes” its way into the channel. He said the turmoil could be a problem, focusing on the latest construction. “We couldn’t see it in a digital model,” he said. Discovery can lead to tweak of design.
The tools are mounted around a model whose sockets are connected to long white plastic tubes that return to the sample bottle racks. During many model trials, as water flowed at different rates, water entered bottles, and each recorded the amount of sand and water.
There is a second model of the car, which includes small mosaics that fit the scale of a heavy stone, known as a riprap, that will drive the real wave. And after the tests of this Mid-Barataria model are completed, the model will be cut and the second one introduced, which will represent the second diversion.
Something that is not tested by the model: Proposed liquefied natural gas delivery terminal, which would sit directly upstream and could affect the flow of rivers. The: controversial project They are still being debated by state agencies, and work is under way on computational models to determine whether the project will hinder diversion, Mr Bart said.
Some people in the commercial fishing and oyster industry are opposed to diversions, which will inevitably bring fresh water into the more salted parts of the water and estuaries and change the salt balance. Project designers plan to minimize these effects by opening gates only at certain times of the year, and only by volumes of water that will ensure the best balance of clean water and sand and sediment.
Mr. Muth of the Wildlife Group said the concerns of fishermen are big. Even without action, he said: “The final game is little more than a river mouth.”
He said that inaction is not an option. “The sea is going to win the fight.”
Fish and oyster populations may be displaced as salinity changes, but “there will always be places where salt is appropriate,” he said. To rebuild the land. “We only have one effective tool that is Mississippi and the sediment that flows down it,” he said.
“We have to unleash the power of the river, the river that Delta first built.”