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Joseph M. Dorava

Publications and source records attributed to Joseph M. Dorava.

At least 19 recordsLinked to original sources
USGS1999

Concentrations of fecal coliform bacteria in creeks, Anchorage, Alaska, August and September 1998

Water samples were collected from five creeks in undeveloped, semi-developed, and developed areas of Anchorage, Alaska, during August and September 1998 to determine concentrations of fecal coliform bacteria. In undeveloped areas of Ship, Chester, and Campbell Creeks, and the semi-developed area of Rabbit Creek, concentrations of fecal coliform bacteria ranged from less than 1 to 16 colonies per 100 milliliters of water. In the semi-developed area of Little Rabbit Creek, concentrations ranged from 30 to 860 colonies per 100 milliliters of water. In developed areas of the creeks, concentrations of fecal coliform bacteria ranged from 6 to 80 colonies per 100 milliliters of water.

Open-File Report↗
USGS1999

Physical, chemical, and biological data for two sites on the upper Kenai River, Alaska, 1998

Water-quality data were collected and stream characteristics were documented from two sites along the upper Kenai River in the Kenai National Wildlife Refuge, Alaska. These data were collected to describe the current status of the sites and to provide baseline information from which changes in the future could be evaluated. Physical characteristics included channel geometry surveys, and measurements of channel widths and water discharge at each site. Chemical data included stream water temperature, dissolved-oxygen concentration, pH, specific conductance, E. coli and fecal coliform counts, and nutrient concentration. Data on concentrations of trace elements and various organic compounds in bed sediments and the tissue of slimy sculpin were also collected. Biological characteristics were evaluated using measurements of the bacteria, benthic macroinvertebrate, and fish communities.

Open-File Report↗
USGS1999

Water-quality data for the Talkeetna River and four streams in National Parks, Cook Inlet basin, Alaska, 1998

Five streams in the Cook Inlet Basin, Alaska, were sampled in 1998 to provide the National Park Service with baseline information on water quality. Four of these streams drain National Park Service land: Costello and Colorado Creeks in Denali National Park and Preserve, Johnson River in Lake Clark National Park and Preserve, and Kamishak River in Katmai National Park and Preserve. The fifth site was on the Talkeetna River, outside of national park boundaries. Samples of stream water, streambed sediments, and fish tissues were collected for chemical analyses. Biological and geomorphic information was also collected at each site. Nutrient concentrations in stream water were low and commonly were less than analytical detection limits. Analyses of fish tissues for 28 organochlorine compounds at Talkeetna River and Costello Creek produced just one detection. Hexachlorobenzene was detected at a concentration of 5.70 micrograms per kilogram in slimy sculpin from the Talkeetna River. Streambed sediment samples from the Talkeetna River had three organochlorine compounds at detectable levels; hexachlorobenzene was measured at 13 micrograms per kilogram and two other compounds were below the minimum reporting levels. At Colorado Creek, Johnson River, and Kamishak River, where fish samples were not collected, no organochlorine compounds were detected in streambed sediment samples. Several semivolatile organic compounds were detected at Colorado Creek and Costello Creek. Only one compound, dibenzothiophene, detected at Costello Creek at a concentration of 85 micrograms per kilogram was above the minimum reporting limit. No semivolatile organic compounds were detected at the Talkeetna, Kamishak, or Johnson Rivers. Trace elements were detected in both fish tissues and streambed sediments. Macroinvertebrate and fish samples contained few taxa at all sites. Total numbers of macroinvertebrate taxa ranged from 19 at the Johnson River to 38 at the Talkeetna River. Diptera were the most abundant and diverse order of macroinvertebrates at all sites. Total numbers of diptera taxa ranged from 8 at the Kamishak River to 19 at the Talkeetna River. Fish communities were represented by a maximum of nine taxa at the Talkeetna River and were absent at Colorado Creek. The Johnson River sampling site produced small numbers of juvenile Dolly Varden, and Costello Creek produced small numbers of both juvenile Dolly Varden and slimy sculpin.

Alaska↗
USGS1999

Water-quality assessment of the Cook Inlet Basin, Alaska — Environmental setting

The Cook Inlet Basin in Alaska is one of 59 study units selected for study for water-quality assessment as part of the U.S. Geological Survey's National Water-Quality Assessment program. The Cook Inlet Basin study unit encompasses the fresh surface and ground waters in the 39,325 square-mile area that drains to Cook Inlet, but does not include the marine waters of Cook Inlet. This report describes the natural factors (climate, physiography, geology, soils, land cover) and the human factors (population, land use, water use) that affect water quality, which is the first step in designing and conducting a multidisciplinary regional water-quality assessment. The surface- and ground-water hydrology, and the aquatic ecosystems of the Cook Inlet Basin are described. The report provides an overview of existing water-quality conditions and summarizes the results of selected water-quality studies of the basin.

Alaska↗
USGS1999

Effectiveness of streambank-stabilization techniques along the Kenai River, Alaska

The Kenai River in southcentral Alaska is the State's most popular sport fishery and an economically important salmon river that generates as much as $70 million annually. Boatwake-induced streambank erosion and the associated damage to riparian and riverine habitat present a potential threat to this fishery. Bank-stabilization techniques commonly in use along the Kenai River were selected for evaluation of their effectiveness at attenuating boatwakes and retarding streambank erosion. Spruce trees cabled to the bank and biodegradable man-made logs (called 'bio-logs') pinned to the bank were tested because they are commonly used techniques along the river. These two techniques were compared for their ability to reduce wake heights that strike the bank and to reduce erosion of bank material, as well as for the amount and quality of habitat they provide for juvenile chinook salmon. Additionally, an engineered bank-stabilization project was evaluated because this method of bank protection is being encouraged by managers of the river. During a test that included 20 controlled boat passes, the spruce trees and the bio-log provided a similar reduction in boatwake height and bank erosion; however, the spruce trees provided a greater amount of protective habitat than the bio-log. The engineered bank-stabilization project eroded less during nine boat passes and provided more protective cover than the adjacent unprotected natural bank. Features of the bank-stabilization techniques, such as tree limbs and willow plantings that extended into the water from the bank, attenuated the boatwakes, which helped reduce erosion. These features also provided protective cover to juvenile salmon.

Alaska↗
USGS1997

Preliminary Volcano-Hazard Assessment for Redoubt Volcano, Alaska

Redoubt Volcano is a stratovolcano located within a few hundred kilometers of more than half of the population of Alaska. This volcano has erupted explosively at least six times since historical observations began in 1778. The most recent eruption occurred in 1989-90 and similar eruptions can be expected in the future. The early part of the 1989-90 eruption was characterized by explosive emission of substantial volumes of volcanic ash to altitudes greater than 12 kilometers above sea level and widespread flooding of the Drift River valley. Later, the eruption became less violent, as developing lava domes collapsed, forming short-lived pyroclastic flows associated with low-level ash emission. Clouds of volcanic ash had significant effects on air travel as they drifted across Alaska, over Canada, and over parts of the conterminous United States causing damage to jet aircraft. Economic hardships were encountered by the people of south-central Alaska as a result of ash fallout. Based on new information gained from studies of the 1989-90 eruption, an updated assessment of the principal volcanic hazards is now possible. Volcanic hazards from a future eruption of Redoubt Volcano require public awareness and planning so that risks to life and property are reduced as much as possible.

Open-File Report↗
USGS1996

Balancing the three R's (regulation, research, and restoration) on the Kenai River, Alaska

The Kenai River is Alaska’s most popular salmon sport fishery. By attracting fishermen, the river contributes about $40 million annually to the local economy. Much of the fishing effort is in pursuit of the river’s chinook salmon, which are among the largest in the world. Many people benefit from the river through its numerous recreational opportunities or by making a living providing fishery support services. To preserve the fishery and the opportunities the river provides, we must find the proper balance of regulation, research, and restoration in the watershed.

Alaska↗