New Software Tool Analyzes Effect of Stream and Lake Levels on Adjacent Lands plus 1 more

[USGS Newsroom <oc_web@xxxxxxxx>]

Title: USGS Newsroom

New Software Tool Analyzes Effect of Stream and Lake Levels on Adjacent Lands plus 1 more

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New Software Tool Analyzes Effect of Stream and Lake Levels on Adjacent Lands

Posted: 03 Apr 2013 10:00 AM PDT

PORTLAND, Ore. — The U.S. Geological Survey has developed the "Shoreline Management Tool," a GIS software program designed to test ways of managing land and water resources adjacent to a lake or stream. The new software tool will help water-, land-, and wildlife-resource managers balance competing needs when managing surface-water levels for water quantity, water depth, area of inundation, and area of dry land. These factors relate directly to water supply, water quality, shoreline habitat for plants and animals, and human use of water and land areas.

Assessing the effects of changing surface-water levels historically has been difficult because of the complexity of the analysis. The management tool enables the user to define criteria such as water depth and land-surface slope and aspect to identify areas where conditions meet the needs for certain land or water uses or that provide habitat suitable for specific plants and animals.

The tool comprises an interactive GIS program and spreadsheets that allow users to specify the input data and criteria for analysis, process the data, and create results in the form of maps, data tables, and graphs. The tool is designed for use by natural-resource managers with only limited expertise with GIS.

Although the tool was initially developed to evaluate conditions in the lower Wood River Valley in the upper Klamath Basin, Oregon, it is designed to be transferable to other areas using easily generated or readily available data. 

The Shoreline Management Tool was conceived and developed by the USGS with cooperation from the Bureau of Land Management.

The program is documented in the report, "The Shoreline Management Tool—An ArcMap Tool for Analyzing Water Depth, Inundated Area, Volume, and Selected Habitats, with an Example for the Lower Wood River Valley, Oregon," by Daniel T. Snyder, Tana L. Haluska, and Darius Respini-Irwin, is published as U.S. Geological Survey Open-File Report 2012–1247 and is available online.

USGS Finds No Influence of Oil Platforms on Contaminant Levels in California Fishes

Posted: 02 Apr 2013 02:09 PM PDT

Fishes residing near oil platforms in southern California have similar contaminant levels as fishes in nearby natural sites, according to two recent reports by the U.S. Geological Survey, which were conducted to assist the Bureau of Ocean Energy Management (BOEM) in understanding potential consequences of offshore energy development.

Since the underwater portion of many offshore oil and gas platforms often provides habitat to a large number of fishes and invertebrates, some stakeholders have called for ocean managers to consider a "rigs-to-reefs" option during the decommissioning phase of a platform. This option would maintain some of the submerged structure to function as an artificial reef after oil and gas production has ended. The findings of this study address questions regarding how the industrial legacy of this kind of artificial reef may affect local fish populations.

Scientists analyzed the amount of contaminants from crude oil exposure present in three species of fish residing at oil platforms within the Santa Barbara Channel and the San Pedro Basin in California.  The amount of contaminants present in fish tissue samples at seven platform sites was compared to samples at natural nearby sites. The brand new and recent USGS reports are available online.

"As part of this study, we developed methods capable of detecting the extremely low levels of contaminants that we anticipated in these ocean fishes, especially since they avoid natural oil seeps," said USGS scientist Robert Gale. "These results will assist decision-makers in helping to protect the environment off the coast of California." 

Some of the most important contaminants related to oil operations are polycyclic aromatic hydrocarbons (PAHs). Several PAHs are probable human carcinogens and many are toxic to fish and other aquatic life. Scientists were able to develop a new, more accurate method of sampling small traces of PAHs that may have been ingested and broken down within the fish. Samples were taken from species thought to be most sensitive to PAH contamination. These species, including Pacific sanddab, kelp rockfish, and kelp bass, also tend to be targeted by fishermen. PAH concentrations were either very low or undetectable in all fish sampled for this study.

"These important results suggest two things," said BOEM marine biologist Donna Schroeder. "First, existing offshore oil platforms provide food and shelter to local fishes without increasing their background contaminant loads. Second, since there is no detectable PAH signal from ongoing operations, we would expect that if the State of California wanted to implement a rigs-to-reefs program, there would likely be no change, pollution-wise, in the quality of the offshore environment, which appears to be pretty good."

Scientists also looked at industrial chemicals in the Pacific sanddab species, including polychlorinated biphenyls (PCBs), flame retardants (polybrominated diphenylethers, PBDEs), and pesticides (OCPs). These contaminants were also found at low levels in all fish sampled, with no observed pattern between natural and platform habitats.

The Bureau of Ocean Energy Management promotes energy independence, environmental protection and economic development through responsible, science-based management of offshore conventional and renewable energy. While the agency is responsible for analyzing the potential environmental impacts of removing oil and gas platforms in federal waters, the Bureau of Safety and Environmental Enforcement approves applications for decommissioning and ensures that they are conducted safely and in compliance with federal regulations. For additional information on BOEM activities, visit http://www.boem.gov/.