About these ads

The ‘greening’ of the Colorado River Delta

The Colorado River Delta in May, 2014. Photo courtesy NASA.

The Colorado River Delta in May, 2014. Photo courtesy NASA.

Science team tracks effects of historic pulse flow

Staff Report

FRISCO — Last May’s pulse flow in the Colorado River helped revive vegetation along a huge swath of the river’s edge, triggering new plant growth and raising the water table in the delta. After comparing satellite images taken August 2013 with new images from this year, scientists calculated a 23 percent increase in the greenness of riparian zone vegetation. Continue reading

About these ads

Study: Toxic stream pollution from road salt doubles

sdfg

Pollution from road salt is increasing quickly, a new USGS study found.

EPA standards for chloride exceeded at one in three sampling sites

Staff Report

FRISCO — Many streams in the northern U.S. are polluted to toxic levels by salt deicers, the U.S. Geological Survey said in a new study that found the frequency of these occurrences nearly doubling in two decades.

Chloride levels increased substantially in 84 percent of the urban streams analyzed, the researchers said, using data going back to 1960 and ending as recently as 2011. Continue reading

Colorado: Senators Udall and Bennet ask President Obama to use Antiquities Act to designate Browns Canyon as a national monument

Gridlock in Congress prompts request for designation

pu

There’s a new push to create a national monument along the Arkansas River.

Staff Report

FRISCO — Citing gridlock in Congress, Colorado’s U.S. Senators Mark Udall and Michael Bennet have asked President Obama to consider designating Browns Canyon, in Chaffee County, as a national monument under the Antiquities Act.

The request comes as Congress has all but ignored a huge backlog of public lands bills primarily based on ideological opposition to land protection measures by House Republican committee chairs.

According to Udall and Bennet’s Nov. 25 letter to President Obama, community leaders in the Browns Canyon area suggested the Antiquities Act path, recognizing the significant economic benefits of the designation for regional tourism-based businesses. Continue reading

Environment: Bulkhead a big step in Peru Creek cleanup

All-out remediation effort targets acid mine drainage near Keystone Ski Area

Remediation work in progress at the Pennsylvania Mine site in Summit County, Colorado. Photo via Snake River Watershed Task Force.

Remediation work in progress at the Pennsylvania Mine site in Summit County, Colorado. Photo via Snake River Watershed Task Force.

By Bob Berwyn

FRISCO — For decades, the abandoned Pennsylvania Mine has been oozing heavy metals — zinc, manganese, cadmium, lead and and arsenic — into the waters of Peru Creek, a small tributary of the Snake River near Keystone, Colorado. The site has been the focus of intensive study during the past 15 years with the goal of improving water quality downstream.

Last week, engineers and environmental experts took a big step toward trying to staunch that flow by blocking one of the mine tunnels. If all goes well, the new bulkhead could reduce the direct discharge from the mine by about two-thirds, said Jeff Graves, a remediation expert with the Colorado Division of Reclamation Mining and Safety.

Graves explained that the new plug should force the water back into its natural underground pathways, trickling and percolating down through layers of rock and earth, and not as prone to the oxidation that’s key in the formation of acid mine drainage. Essentially, the work will restore the groundwater flow to more natural, pre-mining conditions, he said. Continue reading

Colorado River flows about average for 2014 water year

Storage still near all-time lows

asdf

A 2014 water year map shows the continuing drought conditions in California, as well as dry patches from Texas, extending north into Oklahoma.

Staff Report

FRISCO — Near-average inflow to Lake Powell the past 12 months helped maintain storage at a similar level to last year in the key Colorado River reservoir. According to the Bureau of Reclamation. Continue reading

Microclimates may buffer some streams from global warming

Low flows in high country streams this summer. PHOTO BY BOB BERWYN.

Microclimates may partially buffer some streams, at least temporarily, from warming air temperatures. bberwyn photo

‘The one constant is that a healthy watershed will be more resilient to climate change than one that isn’t healthy …’

Staff Report

FRISCO — Global warming is all but sure to raise stream temperatures in many areas, but it turns out that changes in air temperatures don’t offer a reliable proxy for projecting those changes.

Eapecially in the mountains streams of the West, topography and riparian conditions are huge factors in regulating stream temperatures.

The correlation between air temperature and stream temperature is surprisingly tenuous, according to stream ecologists at Oregon State University, who examined historic stream temperature data over a period of one to four decades from 25 sites in the western United States. Continue reading

Unhealthy mercury levels found in 25 percent of U.S. streams

These rainbows may not break any records, but they were caught in Dillon Reservoir, where it can sometimes be notoriously tricky to land fish.

Is there mercury in your trout?

National assessment by USGS pinpoints regional mercury hotspots

Staff Report

FRISCO — Widespread mercury contamination is one of the many signs of continued global environmental degradation. Currently, there are fish consumption advisories for mercury in all 50 states in the U.S. Methylmercury concentrations in fish exceed the human health criterion in about one in four U.S. streams.

A new USGS report takes a comprehensive look at mercury contamination in streams across the United States, finding the highest concentrations in the Southeast and in the West, where some streams were degraded by historic mining activities.

Mercury is a potent neurotoxin that accumulates in fish to levels of concern for human health and the health of fish-eating wildlife. Much of the mercury originates from combustion of coal and can travel long distances in the atmosphere before being deposited. This can result in mercury-contaminated fish in areas with no obvious source of mercury pollution. Continue reading

Follow

Get every new post delivered to your Inbox.

Join 7,858 other followers