More than 1,000 dams have been removed across the United States because of safety concerns, sediment buildup, inefficiency or having otherwise outlived usefulness. A paper published today in Science finds that rivers are resilient and respond relatively quickly after a dam is removed. 

“The apparent success of dam removal as a means of river restoration is reflected in the increasing number of dams coming down, more than 1,000 in the last 40 years,” said lead author of the study Jim O’Connor, geologist with the U.S. Geological Survey. “Rivers quickly erode sediment accumulated in former reservoirs and redistribute it downstream, commonly returning the river to conditions similar to those prior to impoundment.”

Each year, Earth Day -- April 22 -- marks the anniversary of what many consider the birth of the modern environmental movement in 1970.

The height of hippie and flower-child culture in the United States, 1970 brought the death of Jimi Hendrix, the last Beatles album, and Simon & Garfunkel’s “Bridge Over Troubled Water”. Protest was the order of the day, but saving the planet was not the cause. War raged in Vietnam, and students nationwide increasingly opposed it.

The United States currently leads the world in the number of plug-in electric vehicles on the road, capturing 41% of the global market. Though the market can be traced back to the early-to-mid 1990s with the release of the Chrysler TEVan and the General Motors EV1, it wasn’t until the second wave of vehicles such as the Nissan Leaf and the Chevrolet Volt, both introduced in 2010, that plug-in electric cars started to become a success in the US.

It was Tesla Motors with its Roadster series which first entered production in 2008 that reignited this interest in the market though. The small company was founded by Martin Eberhard and Marc Tarpenning in 2003 before current CEO Elon Musk joined the company the following year and led the business to new heights with links to new battery technologies that made plug-in electrical vehicles a more viable option for everyday journeys.

Strange as it sounds, flood control can be part of the solution to managing California’s droughts. University of California scientists have shown that making more room for floodwaters can improve the state’s groundwater supplies and fisheries.

Removing some levees or rebuilding aging ones some distance away from riverbanks can appreciably replenish aquifers during wet years, providing some relief during droughts.

Nine states report record low snowpacks. A report from the US Department of Agriculture states, “the largest snowpack deficits are in record territory for many basins,especially in the Cascades and Sierra Nevada where single – digit percent of normal conditions prevail. Very low snowpacks are reported in most of Washington, all of Oregon, Nevada, California, parts of Arizona, much of Idaho, parts of New Mexico, three basins in Wyoming, one basin in Montana, and most of Utah.” This region is undergoing the warmest winter temperatures since record keeping began in 1895.

The U.S. Environmental Protection Agency (EPA) announced today that it is developing an early warning indicator system using historical and current satellite data to detect algal blooms. EPA researchers will develop a mobile app to inform water quality managers of changes in water quality using satellite data on cyanobacteria algal blooms from three partnering agencies-- NASA, NOAA, and the U.S. Geological Survey. 

The multi-agency project will create a reliable, standard method for identifying cyanobacteria blooms in U.S. freshwater lakes and reservoirs using ocean color satellite data. Several satellite data sets will be evaluated against environmental data collected from these water bodies, which allows for more frequent observations over broader areas than can be achieved by taking traditional water samples.
 

President Barack Obama has seemingly spent a lot of his second term trying to cement his reputation as one of the United States’s most environmentally conscious leaders. However, his most recent decision to approve controversial oil and gas drilling in the Arctic is certain to lose him favor within the environmental community. How can he preach about the consequences of global warming and carbon emissions and simultaneously give corporations permission to drill in a vulnerable region for decades to come?

As Scientific American reminds us, although we tend to romanticize some of Obama’s environmental policy, his decision to give Arctic drilling a thumbs-up is not incongruent with his overall scheme to have America reliant on multiple sources of energy, including both renewable options, as well as gas and oil.

In the past few weeks, giant cranes have unloaded some 1,500 solar panels onto the Knesset's (the Israeli parliament) roofs. These panels were created especially for the Knesset's solar field, which is laid out over 4,650 square meters of the Knesset roofs and will have an installed capacity of 450 kilowatts. The solar array, which cost the Knesset NIS 2.4 million, will create some 10% of the Knesset's electricity, and together with additional energy-saving measures, it will help reduce the Knesset's energy use by a third.

The solar array is expected to save the Knesset NIS 300,000 every year. It will operate according to the net-metering method, under which electric energy generated by an electric consumer from an eligible on-site generating facility and delivered to the local distribution facilities may be used to offset electric energy provided by the electric utility to the electric consumer during the applicable billing period. The Knesset's solar array will be the first of any national institution to operate according to this method. Director General of the Knesset, Mr. Ronen Plot, hopes that other government institutions and local authorities will follow suit and establish solar fields of their own.

Mutiny on the Bounty is a tale about the Royal Navy ship Bounty. On April 28, 1789, Fletcher Christian led sailors in a mutiny against their captain, Lieutenant William Bligh. So the story goes, the captain was set afloat in a small boat along with crew members who were loyal to him, while the mutineers settled on Pitcairn Island or Tahiti and burned Bounty off Pitcairn to avoid detection.

Today Pitcairn island’s population is about 50 people, including descendants of Fletcher Christian, and the surrounding waters where the Bounty supposedly went down in flames has just become the world’s largest contiguous ocean reserve.

This is great news for the sanctity of the Pacific ocean and its inhabitants.

Last month ENN launched a new mobile app available at the iTunes store making it easier for you to connect with us and stay up to date with groundbreaking environmental news. Now, ENN releases the mobile app at Google Play, making it compatible for Android users.

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