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THE RIVER BENEATH THE RIVER

As part of an ongoing effort to make content more accessible, LAM will be making select stories available to readers in Spanish. For a full list of translated articles, please click here.

Click above for a full PDF of the translated text, with English text available below.

BY JENNIFER REUT

FROM THE NOVEMBER 2018 ISSUE OF LANDSCAPE ARCHITECTURE MAGAZINE.

 

For a long time, the Anacostia River didn’t even have a name. It was just the Eastern Branch, the other, less promising section of Washington, D.C.’s better known and more distinguished river, the Potomac. But it was always known as a fortunate course to the Nacotchtank, the Native Americans who used it as a trading post, and later to the European colonists who relied on the river’s deep port at Bladensburg, Maryland, to carry tobacco, and to the generations of farmers, tradesmen, and laborers who never seemed to run out of fish, fowl, and game to hunt. For nearly nine miles, the Anacostia eased in and out with the tide, with no particular urgency, toward its confluence with the Potomac, tracing an unhurried flow through thousands of acres of tidal wetlands.

Of course, that was before the port and the shipping channels silted up in the 19th century from agricultural misuse; before the river was (more…)

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BY MEG CALKINS, FASLA

New technologies can reduce the environmental footprint of the most-used construction material.

FROM THE JULY 2017 ISSUE OF LANDSCAPE ARCHITECTURE MAGAZINE.

Concrete in the 21st century promises to be a more sustainable material, and given the nine billion metric tons used globally each year, it must be. Portland cement, the binding agent in ordinary concrete, has a very high carbon footprint, resulting in just under one ton of carbon dioxide (CO2) released for every ton of cement produced. With 4.2 billion metric tons of the binder used each year worldwide, cement production is responsible for nearly 8 percent of total global carbon emissions. The high lime content of ordinary portland cement contributes about two-thirds of cement’s CO2 impact through the process of limestone calcination. The other one-third of CO2 released is from combustion of fossil fuels.

Technologies to improve the carbon footprint of concrete are currently in the early stages of development, but some, including carbon sequestration in concrete and substantial reductions of cement using energetically modified cement, are now commercially available. Concrete surface products for paving and walls to scrub air pollution, as well as new self-healing concrete products, are also worth investigating. We have heard about some of these innovations for a decade or more in the research community, but many are finally being brought to market—some more quickly than others. Europe is ahead of the United States in the adoption of these technologies, largely because of more rigorous clean air and carbon reduction initiatives.

New technologies in any field can take a long time to move from the laboratory to the marketplace, but (more…)

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