Browsing College of Engineering and Mines (CEM) by Author "Nyquist, David"
Effect of Waste Discharges into a Silt-laden Estuary: A Case Study of Cook Inlet, AlaskaMurphy, R. Sage; Carlson, Robert F.; Nyquist, David; Britch, Robert (University of Alaska, Institute of Water Resources, 1972-11)Cook Inlet is not well known. Although its thirty-foot tidal range is widely appreciated, its other characteristics, such as turbulence, horizontal velocities of flow, suspended sediment loads, natural biological productivity, the effects of fresh water inflows, temperature, and wind stresses, are seldom acknowledged. The fact that the Inlet has not been used for recreation nor for significant commercial activity explains why the average person is not more aware of these characteristics. Because of the gray cast created by the suspended sediments in the summer and the ice floes in the winter, the Inlet does not have the aura of a beautiful bay or fjord. The shoreline is inhospitable for parks and development, the currents too strong for recreational activities, and, because of the high silt concentration, there is little fishing. Yet, Cook Inlet, for all its negative attributes, can in no way be considered an unlimited dumping ground for the wastes of man. It may be better suited for this purpose than many bays in North America, but it does have a finite capacity for receiving wastes without unduly disturbing natural conditions. This report was written for the interested layman by engineers and scientists who tried to present some highly technical information in such a manner that it could be understood by environmentalists, concerned citizens, students, decision makers, and lawmakers alike. In attempting to address such a diverse audience, we risked failing to be completely understood by any one group. However, all too often research results are written solely for other researchers, a practice which leads to the advancement of knowledge but not necessarily to its immediate use by practicing engineers nor to its inclusion in social, economic, and political decision-making processes. We hope this report will shorten the usual time lag between the acquisition of new information and its use. Several additional reports will be available for a limited distribution. These will be directed to technicians who wish to know the mathematical derivations, assumptions, and other scientific details used in the study. Technical papers by the individual authors, published in national and international scientific and engineering journals, are also anticipated.
The Limnology of Two Dissimilar Subarctic Streams and Implications of Resource DevelopmentLaPerriere, Jacqueline D.; Nyquist, David (University of Alaska, Institute of Water Resources, 1973-03)Because of the relatively undeveloped condition of arctic and subarctic Alaska, an opportunity is presented to draw up water quality management plans before extensive perturbation. These plans cannot, unfortunately , be based upon those drawn up for more temperate regions where much is known about natural stream conditions, for in these Alaskan areas, little is known about the natural physical, chemical, and biological cycles of streams or about their ability to handle the stresses that will be exerted on them should development take place. The Chena River, in subarctic, interior Alaska, near the city of Fairbanks, has been studied to evaluate the impact of pending construction and operation of flood control structures (Frey, Mueller and Berry, 1970). This river however has already been developed, especially along its lower reaches where the city of Fairbanks is situated. The watersheds of the two streams chosen for this study roughly parallel each other, although the Chatanika River watershed is about twice as long as that of Goldstream Creek. In addition to the dissimilarity in size, these two streams also differ in regard to terrain, at least along the respective stretches that were studied. The Goldstream Creek study area runs through a bog and extensive muskeg. The Chatanika River, however, was for the most part sampled in the area of mountainous terrain. The intent of this study was to obtain comprehensive physical and chemical data, to survey the resident invertebrates, and to evaluate the assimilative capabilities of both streams.
A Survey of Lentic Waters with Respect to Dissolved and Particulate LeadNyquist, David; Casper, L. A.; LaPerriere, Jacqueline D. (University of Alaska, Institute of Water Resources, 1972-11)Some of the strongest temperature inversions in the world occur at Fairbanks, Alaska. Benson (1970) has reported that a temperature gradient of 10 to 30C/1OO m is common in the winter inversions that form at Fairbanks. Air pollution is especially severe during these inversions when it is accompanied by the formation of ice crystals in the air, a condition known as ice fog. This phenomenon occurs when the temperature drops below -20F (-35C) (Benson, 1970), and it intensifies with time if the inversion is not broken. The ice crystals in this fog have been found to adsorb dust and gasses, including the lead halides which are present in the air as a result of the combustion of tetraethyl lead and/or other lead-hydrocarbon compounds used as anti-knock additives in automotive gasoline. Lazrus et al. (1970) have found lead concentrations in precipitation to be highly significantly correlated with the amount of gasoline used in the area sampled. There are two factors that bring the concentration of lead to high levels in ice fogs. Evaporation of the ice crystals tends to concentrate pollutants in the air mass, especially over the core area of the city where precipitation is retarded by the heating effect of the city. Also, during the extreme cold weather accompanying this phenomenon, many people allow their cars to idle when they are parked to increase performance and for reasons of personal comfort. Eventually, much of the pollutants suspended in the ice fog is precipitated and causes unnaturally high levels of lead in the snow. (Winchester et al., 1967). It is suspected that some of this particulate lead collected in the snow may be carried along with the associated surface runoff into 1entic (standing) surface waters during thawing. The objectives of this project were: 1. to measure the amount of dissolved and particulate lead in a number of selected 1entic waters in the Fairbanks area, and 2. to measure the amount of lead that has been incorporated into net plankton organisms located in the selected lentic waters.