Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Backcountry water quality tests are good news for campers

07.01.2005


Sierra Nevada waters usually free of troublesome bacteria except in high use areas



Data collected by experts from the UC Davis School of Medicine have revealed that except for some heavily used areas, streams and lakes in the high country of the Sierra Nevada are generally clean and fresh.

The good news for campers can be found in a pair of studies published in the latest issue of the quarterly medical journal Wilderness and Environmental Medicine. UC Davis physician Robert Derlet and pathology researcher James Carlson present data gathered from nearly 100 locations throughout the Sierra Nevada during the summer of 2003, including Yosemite, Sequoia and Kings Canyon national parks. Their goal was to analyze wilderness water quality for the presence of harmful bacteria such as E. coli, which is typically an indicator of contamination from human or animal waste.


Running counter to popular belief, the two researchers downplay the risk of picking up Giardia in backcountry drinking water. In the Sierra Nevada, E. coli and other pathogenic bacteria may pose a greater risk than Giardia for causing waterborne illnesses in people.

"What’s impressive is that more than half of our water sampling sites had no water quality problems whatsoever," said Derlet, a professor of emergency medicine at the UC Davis School of Medicine and an avid backpacker with 30 years of experience hiking in California’s high Sierra. "People still should use water filters or purification techniques like boiling drinking water in the backcountry. But our findings also are an indication of the outstanding job done by National Park Service in its wilderness management."

Derlet has spent the past five years on water quality studies in the Sierra Nevada. From his recent sampling sites, only 17 had levels high enough to be directly linked to recreational use or the presence of livestock.

"For these two studies, we looked at nearly100 streams and lakes over the 400-mile long mountain range," observed Derlet, who has given presentations to wilderness rangers about infectious diseases and backcountry medicine."We’ve also analyzed water at many more Sierra Nevada lakes and streams this past summer with consistent results. It’s not surprising that waterways below roads, popular trails and well-used cattle grazing areas often show the presence of harmful bacteria. However, it will probably take a number of years and some sustained funding to pinpoint the exact causes."

The UC Davis physician says his studies are only a snapshot in time, and that all streams and lakes tested in wilderness areas typically contain a certain amount of naturally occurring aquatic bacteria. Low levels of coliform bacteria actually can be part of the natural environment. If bacteria were not present in the water, it would jeopardize the balance of the aquatic ecosystem, including everything from frogs to fish.

Currently working with renowned Lake Tahoe expert and UC Davis professor Charles Goldman, Derlet has several other water quality findings in the Sierra that he also hopes to research:

  • Lakes are typically ’cleaner’ than creeks, possibly because the ultraviolet rays of sunlight work better at killing off bacteria in calm waters of a lake than in the tumbling flows of a stream;
  • Algae growth in backcountry waterways appears to be getting worse;
  • Bacteria readings appear higher at the beginning of spring runoff rather than later in the summer when water levels are lower and water quality is thought to be poorer;
  • Valley air pollution could be contributing to water quality problems in the Sierra Nevada.

Carole Gan | EurekAlert!
Further information:
http://www.ucdmc.ucdavis.edu
http://www.wms.org

More articles from Ecology, The Environment and Conservation:

nachricht Conservationists are sounding the alarm: parrots much more threatened than assumed
15.09.2017 | Justus-Liebig-Universität Gießen

nachricht A new indicator for marine ecosystem changes: the diatom/dinoflagellate index
21.08.2017 | Leibniz-Institut für Ostseeforschung Warnemünde

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: The pyrenoid is a carbon-fixing liquid droplet

Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.

A warming planet

Im Focus: Highly precise wiring in the Cerebral Cortex

Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.

The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

Im Focus: Ultrafast snapshots of relaxing electrons in solids

Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!

When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...

Im Focus: Quantum Sensors Decipher Magnetic Ordering in a New Semiconducting Material

For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.

Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

Rainbow colors reveal cell history: Uncovering β-cell heterogeneity

22.09.2017 | Life Sciences

Penn first in world to treat patient with new radiation technology

22.09.2017 | Medical Engineering

Calculating quietness

22.09.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>