This thesis examines the influence of different degrees of serial correlation in the streamflow records on optimal operation of a hydroelectric reservoir. This thesis also investigates the practical aspects of choosing different decision variables, considering effects on ease of implementation, total benefit, and actual use for real-time operations. Stochastic dynamic programming was used to optimize the long-term operation of a hydroelectric project with a single reservoir. Reservoir inflows were analyzed using monthly flow record for 58 years with the assumption that monthly inflows are either perfectly correlated, uncorrelated, or partially correlated. Reservoir level change and powerhouse discharge were considered as alternative decision variables for each of the three cases of inflow serial correlation. The optimization results were then examined and compared to determine the significance of the choice of decision variables and to explore the effects of inflow serial correlation on practical operating decisions which might be based on the results of the optimization. It was found that (1) Case 2 in which inflows were assumed perfectly correlated and Case 3 with partially correlated inflows produce, respectively, highest and lowest total expected return, (2) the difference in total expected return between cases depends largely upon the physical characteristics of the system, (3) the reservoir level change decision case produces more conservative results than the discharge decision case, (4) the results from the reservoir level change decision are easier to use for realtime operation than those from the discharge decision case, (5) different results will be produced with different choice of decision variables. / Applied Science, Faculty of / Civil Engineering, Department of / Graduate

Qualitative and quantitative sampling was conducted along a 165 km reach of the river from PRKM 269.4 near Dryden, VA to PRKM 104.8 near Harrogate, TN. Twenty-nine species were observed throughout the entire river, and the highest diversity of 23 species was collected at PRKM 152.6. Mussel abundances (mussels/person-h and mussels/m2) ranged from 0.33 to 21.98 mussels/person-h and 0.00 to 2.24 mussels/m2. Recent recruitment (individuals < 40 mm, depending on the species) was observed for 15 species, including the endangered Epioblasma brevidens, Lemiox rimosus, and Quadrula intermedia. The greatest number of species (6) with evidence of recent recruitment also was found at PRKM 152.6. Data from the quantitative survey were used to simulate several sampling protocols that could be used to develop a long-term monitoring program for the Powell River. Five sites, PRKMs 197.9, 171.4, 159.6, 152.6, and 129.4, were selected for long-term monitoring because of high mussel densities and species richness. Six sampling protocols were simulated using the statistical program MONITOR to determine which protocols, if any, could monitor statistically significant changes in mussel abundance at rates + 10%. Each of the simulated sampling protocols lasted between 15 and 30 y, and employed quantitative sampling at 3 to 5 y intervals. None of the sampling protocols simulated during this study were able to detect declines in mussel abundance < 10%. Two sampling programs were able to detect increases in mussel abundance > 6% when the level of significance was > 0.10, and four sampling programs were able to detect a density increase of > 8% when the level of significance was 0.05. Despite the inability to monitor declines in mussel abundances, a long-term monitoring program is needed for the Powell River. Because qualitative sampling has been repeatedly shown to document species presence more effectively than quantitative sampling, it should be used to monitor changes in species presence and distribution. Quantitative sampling should be employed to monitor juvenile recruitment and changes in size-class structure of populations. Quantitative sampling also should be conducted to monitor overall mussel abundance at sites. Despite the inability to statistically detect changes in mussel density in the Powell River, quantitative sampling can provide valuable information, and the data collected can be used to qualitatively monitor changes in total density at sites. Both species share a similar distribution in the Powell River. Eighteen specimens of Quadrula sparsa were collected between PRKM 230.9 and 152.6, and 68 individuals of Q. intermedia were collected between PRKM 230.9 and 129.4. The highest density of each species was collected at PRKM 152.6, and recent recruitment was observed at PRKMs 152.6 and 153.4. Fresh-dead and relic shells of both species were thin-sectioned to determine individual growth rate and life span. These species complete the majority of their growth during the first 10 y of life, and likely live for a total of 40 to 50 y. One gravid female of Q. intermedia was collected during this study, but no gravid females of Q. sparsa were observed. / Master of Science

A survey of the freshwater mussel fauna was conducted in the Powell River, Virginia, to identify critical habitat for endangered species, quantify substratum composition and coal waste deposition, and to assess population trends during the last half century. Mussels were collected as far upstream as Powell River Mile (PRM) 167.4 near Dryden, Virginia. Endangered species were collected up to PRM 144.6 at Jonesville, Virginia. The sites with greatest diversity were located furthest downstream, and there appeared to be a general decline in the number of species and diversity of mussels from downstream to upstream. Mussel densities also declined proceeding upstream, and specimens were rare above PRM 158.3 near Pennington Gap, Virginia. The highest density occurred at PRM 123.0 near the Tennessee-Virginia border, with 24 mussels/m². Collections per unit effort of sampling concurred with quadrat surveys, indicating a decline in abundance and diversity upstream. Length frequency distributions of the muckets Actinonaias pectorosa and A. ligamentina indicated an absence of smaller mussels at most sites. Sediment samples, collected in riffles at 10 sites to determine particle size distributions and the amount of coal, showed no apparent trends in waste coal from downstream to upstream; however, there were significant negative correlations between PRM location and various fractions of the substratum, indicating a longitudinal sorting of smaller size fractions. Percentages of very fine to medium sand, silt, and coal show marked increases downstream of the North Fork Powell River confluence (PRM 156.6) at Pennington Gap, Virginia. Mussel density had a slightly positive correlation with percent silt (r²=0.346, p=0.0736) but was not correlated with percent coal. Juvenile mussels of Villosa iris were placed on several types of substratum to determine differences in survival. In laboratory experiments, survival of juveniles on coal silt sometimes did not differ from that of juveniles without substratum (survival close to 100%). Survival of juveniles without substratum (93.9%), however, was significantly higher than survival (30.0-63.2%) on three sediment types from the Powell River (p< .001). In field experiments, there was a marginally significant difference in survival of juveniles between two sites (p =.070), with higher survival (47.7%) in sediments from Poteet Ford (PRM 144.6). Survival of juveniles was similar in all laboratory and field experiments. A decline in density of the mussel fauna in the Powell River over the past 15 years was apparent when compared to previous data. Contamination and siltation from coal washing facilities and abandoned mine lands are suspected of contributing to this decline. / Master of Science

A survey of the population characteristics of smallmouth bass (Micropterus dolomieu), rock bass (Ambloplites rupestris), and habitat conditions were conducted in the Powell River, Virginia, to identify potential habitat limitations for these species. The study area consisted of three reaches, which were determined in 1987. The upstream reach was used to monitor effects of coal mining in the upper watershed on the Powell River. The midstream reach, which was below the North Fork Powell River, was used to monitor the possible effects of this tributary and its watershed. The downstream reach appeared to have been impacted by sedimentation less than either of the other reaches. Habitat Suitability Index (HSI) models were used to identify habitat variables that were below optimum for these species in the Powell River, Virginia. Habitat sampling yielded HSI scores for smallmouth bass at each site ranging from 0.67 to 0.76, with a mean of 0.72; scores for rock bass ranged from 0.65 to 0.70, with a mean of 0.69. No trends in HSIs from upstream to downstream were evident. However, substratum, of which sand was dominant in pools, was the variable most frequently below optimum for smallmouth bass (Sl=0.21) and rock bass (SI=0.20). Values for sediment depth, embeddedness, waterborne sediment, and coal were collected in riffles, runs, and pools at 10 sites. Mean sediment depth in pools, embeddedness in riffles and runs, and waterborne sediment deposited in traps monthly in pools decreased from upstream to downstream; however, waterborne sediment in runs did not decrease. Content (by weight) of coal wastes in the substratum did not decrease from upstream to downstream. The embeddedness index in pools (= 1.0), riffles, and runs was not significantly different among the three river reaches. No differences in population abundance, biomass estimates, age and growth, or relative weights (Wr) of smallmouth bass and rock bass were found among the three river reaches. Population estimates of smallmouth bass (34.3/ha) and rock bass (116.6/ha) were lower than those in many other streams in the U.S. Catch-per-unit-effort and biomass of smallmouth bass (2.9/h, 2.6 kg/ha) and rock bass (6.6/h, 2.2 kg/ha) also were lower than those in most other streams. A total of 70 stomachs of smallmouth bass and 166 stomachs of rock bass was examined from fish collected between July 1988 and October 1989. Diets for each species, primarily crayfish and insects, showed no apparent differences among the three river reaches. Abundance of crayfish and hellgrammites were compared; greatest hellgrammite abundance was in the downstream reach (P = 0.032), and there were no significant differences in crayfish abundance among the three river reaches. HSI values showed no significant correlation with catch-per-unit-effort for smallmouth bass or rock bass. No significant correlation was found among sediment depth, catch-per-unit effort, biomass or relative weight of smallmouth bass and rock bass. No correlation was found between the embeddedness index in riffles and biomass of rock bass. There was a significant negative correlation between the embeddedness index in riffles and relative weight of smallmouth bass (P=0.016); however, no correlation existed between the embeddedness index and relative weight of rock bass. There was a significant negative correlation between the embeddedness index in riffles and growth of smallmouth bass (P=0.016); however, there was a significant positive correlation between the embeddedness index and growth of rock bass. There was a significant positive correlation between the embeddedness index in riffles and both hellgrammite abundance (P=0.031) and crayfish abundance (P=0.052) in riffles. No significant correlation was found between the amount of sediment deposited in pools and catch-per-unit-effort of smallmouth bass and rock bass. No significant correlation existed between the amount of sediment deposited in runs and biomass of rock bass. In addition, crayfish density was not correlated with relative weight of smallmouth bass or rock bass. With the available documentation that links population characteristics of smallmouth bass and rock bass to habitat, it is evident that habitat is usually the limiting factor in determining population characteristics; however, there was no significant trend in the correlations presented above. Habitat for smallmouth bass and rock bass in the Powell River, Virginia was suboptimum and sand was the dominant substratum in pools. Population estimates, catch-per-unit-effort, and biomass of smallmouth bass and rock bass in the Powell River are low compared to other U.S. streams. Although it appears that sedimentation has degraded habitat of smallmouth bass and rock bass and contributed to reduced population levels of these species in the Powell River, Virginia, my results were not statistically different among sites with measurable differences in sedimentation. / Master of Science

The decline in mussel fauna of the Powell River has been attributed to extensive mining activities in headwater streams of Wise and Lee counties, Virginia. Surface mining causes erosion, sedimentation, and contamination of water with toxic substances from coal washing and waste piles. Historical water quality data of the Powell River have documented concentrations of metals at levels determined to be toxic to molluscs, specifically zinc (Zn) and copper (Cu). Acute toxicity tests with Zn, Cu, and mixtures of these two metals were conducted with glochidia and juvenile freshwater mussels. Effects of varying conditions such as water source, temperature, length of exposure, species, and lifestage were determined. Additionally, the effects of Powell River sediment on survival and growth of juvenile mussels were evaluated. The Cumberland moccasin shell (Wedionidus conradicus) was the most sensitive species tested, with 24-hr and 48-hr LC50 values for glochidia ranging from 423 to 725 μg Zn/L. Glochidia of the pheasantshell (Actinonaias pectorosa) exhibited LC50 values from 274 to 2886 μg Zn/L, depending on test conditions. Similar results were obtained for glochidia of the rainbow (Villosa iris), with LC50 values ranging from 577 to 4123 μg Zn/L. Juveniles were more sensitive, with 48-hr LC50 values ranging from 360 to 1885 μg Zn/L for A. pectorosa, and 339 to 1122 μg Zn/L for V. iris, depending on test conditions. Juvenile mussels were affected by Zn at lower concentrations as evidenced by valve gaping and a swollen and nonresponsive foot. Copper was 5 to 15 times more toxic than Zn, with 48-hr LC50 values ranging from 52 to 156 μg Cu/L, and ECS5O values ranging from 25 to 115 μg Cu/L for juveniles of A. pectorosa. Copper appeared to exert a different toxic mode of action, as evidenced by closed valves and reduced siphoning. In general, sensitivities of early life stages of mussels to Zn and Cu increased with higher temperature, soft water, and length of exposure. At certain concentrations, Zn seemingly had an antagonistic effect (less than additive) when mixed with Cu. This effect was evidenced by reduced mortality of juveniles in Cu solutions when Zn was added at concentrations of about 400 to 800 μg/L. However, this antagonistic effect was not reflected in the percent of juveniles affected, which increased continuously with increasing metal concentrations. Glass beads were found unsuitable as a control substratum for use in sediment testing with juvenile mussels. Results of sediment tests indicated that sediment in some areas of the Powell River may be toxic to juvenile mussels, and that toxicity may be linked to water quality. After 10 days, survival of juveniles in sediment collected downstream of a coal processing plant was significantly lower than survival in sediment upstream of the plant (p = 0.01). Further, survival in sediments with dechlorinated tap water was significantly higher than survival in sediment with river water (p = 0.0002). After 20 and 30 days, survival was similar among sites and water types. High metal concentrations in the river water appeared to contribute to toxicity, because juveniles in tap water displayed consistently better growth, and initially better survival than juveniles in river water and sediment. This toxicity was not apparent in sediments collected from the same sites less than two months later, suggesting the character of the sediments may change as new suspended sediment is deposited. The USEPA water quality criteria for Zn (adjusting for water hardness) are 174 μg/L (acute) and 158 μg/L (chronic), whereas copper criteria are set at 28 μg/L (acute) and 18 μg/L (chronic). Powell River water samples collected during 1991 contained concentrations of Zn and Cu exceeding these criteria, as well as concentrations shown to have adverse effects on mussel populations. Results suggest that some metals are introduced into the river system in runoff, whereas Cu is being introduced as an episodic event. Intensive monitoring of water quality is needed to identify specific sources of metal pollution. If levels of heavy metal concentrations remain high, then the declining mussel populations of the Powell River will not recover, and endangered species may be extirpated from Virginia. / Master of Science

This thesis develops a conceptual framework that could be used to understand, assess and balance water resources supply and demand in regions where data are limited. The framework is then applied to a case study of Texada Island in British Columbia. The flow of water into and out of Texada is calculated using the Thornthwaite water balance method which uses average monthly precipitation and monthly daily average temperature data. The stock of surface water is estimated using existing data on lake volumes in conjunction with the results of analyses of air photographs and topographic maps. After the analysis of maps, reports, and interviews with mining personnel regarding the island's geology, likely aquifers were identified and their approximate water storage capacity was calculated. The present rate of water use was determined from interviews with island residents and industry personnel, field observations, analysis of available data and a review of the relevant literature on water demands by different water using sectors. Finally, to determine whether water supplies on the island were adequate to meet future demands, scenarios were constructed for analysing potential water use to 1996 by various water using sectors. The results of the supply-demand analysis revealed that on an annual and region-wide basis, water on Texada is abundant and will be adequate to meet expected demands to 1996, and likely beyond. However, there are some local areas that currently experience water shortages during the low flow and peak demand period during the summer months. The management options that were determined to be the most appropriate solution to summer water shortages are, in the short-term, trucking in water and selective restrictions on water use during the peak demand period. In the medium to long-term, the diversion of surface water and the development of groundwater are the most appropriate solutions to water shortages on Texada. Next steps for planning the management of water resources on Texada Island are suggested. The initial and most important of these involves abandoning the ad hoc approach that now exists for dealing with water resources on the island and adopting a strategic, co-operative and co-ordinated approach involving residents and to a lesser extent, the Powell River Regional District, of which Texada is a part. / Applied Science, Faculty of / Community and Regional Planning (SCARP), School of / Graduate

A freshwater mussel survey was conducted in Indian Creek, Tazewell County, Virginia, during 1996 and 1997. Fifteen species were identified, including the federally endangered <i>Epioblasma florentina walkeri<i>, <i>Villosa perpurpurea</i>, and <i>Quadrula cylindrica strigillata</i>. Population assessments and fish host identifications were completed for the tan riffleshell and purple bean populations. Host fish for <i>E. f. walkeri</i> were limited to the banded and mottled sculpin, greenside darter, redline darter, fantail darter, and snubnose darter. Fish hosts identified for <i>V. perpurpurea</i> also were the banded and mottled sculpin, greenside darter, and redline darter. Size class structure of the tan riffleshell population ranged from 19.9 to 53.3 mm, with the population estimated at nearly 700 individuals with a density of 0.015/m². Size class structure of the purple bean population ranged from 22.9 to 66.7 mm, with the population estimated at only 70 individuals with a density of 0.002/m². Host fish also were identified for <i>Dromus dromas</i> and <i>Lemiox rimosus</i>. The fantail darter was identified as a host for <i>D. dromas</i>, with the snubnose darter serving as a host for <i>L. rimosus</i>. Additional percids were implicated as hosts for both mussel species. A molecular genetic key for identifying host fishes of the upper Clinch River also was constructed. The key was constructed through the analysis of restriction fragment length polymorphisms from amplified regions of mussel DNA. Thirty-six unionid species were incorporated into the key. No host fishes were identified due to an unsolved problem with amplifying DNA from glochidia collected from wild fish. / Master of Science