THE APPLICATION OF HYDROLOGIC MODELS TO SMALL WATERSHEDS HAVING MILD TOPOGRAPHY1

ABSTRACT: The application of hydrologic models to small watersheds of mild topography is not well documented. This study evaluates the applicability of hydrologic models described by Huggins and the Soil Conservation Service to small watersheds by comparing the simulated and actual hydrograph for both gaged and ungaged situations. The annual maximum rainfall events plus storms exceeding 2.5 inches from 25 years of rainfall and runoff data for two small watersheds were selected for the model evaluations. These storms had a variety of patterns and occurred on many different watershed conditions. Simulated and actual hydrographs were compared using a parameter which contained volume, peak, and shape factors. One-half of the selected storms were used to calibrate the models. For both models, there were no significant differences between the simulated and actual runoff volumes and peak runoff rates. Parameters obtained during the calibration process and relationships developed to estimate antecedent moisture and to modify tabulated runoff curve numbers were used to simulate the runoff hydrograph from the remaining storms. These remaining storms or test storms were simulated only once in order to imitate an ungaged situation. In general, both the Huggins and SCS model performed similarly on the test storms, but the level of model performance was lower than that for the calibration storms. For both models, the two-day antecedent rainfall was more important than the five-day in determining antecedent moisture and modifying tabulated curve numbers. The time of concentration which resulted in good hydrograph simulations was about three times larger than that estimated using published empirical relationships.     

A note on empty bottles

This note examines the second-order conditions of the Massel-Parrish (M-P) model of a beverage market in which a monopolist producer of beverages packaged in ‘private mould’ bottles has monopsony power in the market for the empty bottles. Customers pay only the shelf price if they return the empty bottle; and, the shelf price plus the forfeited deposit if they discard it. The analysis determines directional changes in the optimal shelf price, deposit levels, and unit sales resulting from changes in each of five demand and three supply parameters. Potential effects of current legislation requiring mandatory deposits on all beverage containers are also analysed.     

METABOLIC RESPONSES OF AQUATIC BACTERIAL POPULATIONS TO SELECTED INSECTICIDES1

ABSTRACT: Indigenous bacterial populations from a fresh water reservoir were treated by adding five mg/1 Sevin or Malathion to the water at 23, 28, and 33 C. The degradation of Sevin was evidenced by the increased uptake of O₂ as measured by Warburg manometry. The principal degradation product of Sevin, 1-naphthol, appeared to stimulate metabolic activity of these populations to the same extent as the parent compound. The addition of Malathion to this system appeared, on the other hand, to suppress metabolic activity to some degree. Warburg manometry was shown to be a useful, rapid method for detecting effects of insecticides on aquatic microbial populations.     

WATER MULTIPLIERS - REGIONAL IMPACT ANALYSIS1

A significant research problem is the assessment of impacts associated with growth and/or decline in a regional economy. A relevant method for analyzing such problems is the Leontief input/output model. Associated with these models are economic multipliers measuring total changes in sales, income, and employment. In this paper, the author contends resource multipliers are equally relevant. The specific form of these multipliers are defined. Water multipliers for a two-county region in central Nevada are presented and their uses described.     

SOCIAL OVERHEAD CAPITAL COSTS OF IRRIGATION DEVELOPMENT IN WASHINGTON STATE1

ABSTRACT: Increased irrigation as a means of achieving economic development can impose significant social costs on the state or region of growth. The growth in population induced by additional irrigation will require new roads, water and sewage facilities, schools, fire and police protection, etc. Also the increased energy demands due to irrigation and growth in economic activity must be met. Capital investments required to service these needs of new development can become very large. This study attempts to measure such social overhead costs or irrigation development for some specific irrigation project areas of Eastern Washington. It is shown that investment costs in overhead items can reach $2,000 per acre irrigated or $70,000 per job created. Alternatively, the annual costs can equal $180 per acre or $6,700 per worker. These costs must be paid locally through increased taxes, utility rates, or costs for services.     

THE DEPENDENCE OF THE RESIDUAL GRAVITY ON HYDRAULIC CONSTANTS IN GLACIAL DEPOSITS1

ABSTRACT: Buried glacial stream channels contain large and easily accessible groundwater resources. Gravity surveys have been frequently applied for their location. A gravity survey in the geohydrologically explored Wood River Valley Area of southern Rhode Island shows extreme lows of -2 mgals over channel depths of maximal 300 feet. Three gravity profiles were observed in east-west direction across a north-south striking stream channel. The bedrock depth increases rapidly towards the south from 130 to 300 feet. The gravity lows observed across each profile are not related to the bedrock depth but rather to the saturated thickness of the main quifer and its hydraulic transmissivity. Well logs indicate that the large change of bedrock depth is solely due to an increase of till of low permeability. The volume of the glacial outwash, which is the major groundwater resource, changes little underneath the three profiles. The gravity lows apear to be directly related to the density contrast between glacial outwash and till. The response to the hydraulically more pertinent units renews the interest in the gravity method as it may have a potential to estimate yields of hydrologically complex aquifers     

Entrainment mortality of Ichthyoplankton: Detectability and precision of estimates

The ability to detect and to develop a precise and accurate estimate of the entrainment mortality fraction is an important step in projecting power plant impacts on future fish population levels. Recent work indicates that these mortailities may be considerably less than 100% for some fish species in the early life stages. Point estimates of the entrainment mortality fraction have been developed based on probabilistic arguments, but the precision of these estimates has not been studied beyond the simple statistical test of the null hypothesis that no entrainment mortaility exists.The ability to detect entrainment mortality is explored as a function of the sample sizes (numbers of organisms collected) at the intake and discharge sampling stations of a power plant and of the proportion of organisms found alive in the intake samples (intake survival). Minimum detectable entrainment mortality, confidence interval width, and type II error (probability of accepting the null hypothesis of no entrainment mortality when there is mortality) are considered. Increasing sample size and/or decreasing sampling mortality will decrease the minimum detectable entrainment mortality, confidence interval width, and type II error for a given level of type I error.The results of this study are considered in the context of designing useful monitoring programs for determining the entrainment mortality fraction. Preliminary estimates of intake survival and the entrainment mortality fraction can be used to obtain estimates of the sample size needed for a specified level of confidence interval width or type II error. Final estimates of the intake survival and the entrainment mortality fraction can be used to determine the minimum detectable entrainment mortality and the type II error.     

THE ENERGY SCENE IN INDIA

The Indian energy scene has undergone a distinct change during the last three decades. In overall terms the reliance on traditional (non-commercial) forms of energy has declined gradually and the share of modern commercial forms of energy has steadily increased. The preference towards commercial forms of energy has resulted in rapid growth of demand, and the growth rate of commercial energy consumption has outpaced the overall growth of the economy. While India has been able to manage oil supplies without much difficulty through indigenous production and imports, there have been balance of payments problems due to the steep increase in the import bill. An overall energy strategy has been formulated for the Sixth Five-Year Plan which will ensure adequate supplies of energy to meet short-term energy requirements while keeping in view the long-term perspective. The plan envisages achieving a balance between energy supplies and demand in the short and medium term by accelerating exploitation of domestic conventional energy resources and managing demand through appropriate measures. In the long term, exploitation of new and renewable energy resources is the basis of energy development strategy. La situation énergétique en Inde a subi une transformation distincte durant ces trois dernières décennies. En termes généraux, la dépendance vis-à-vis des formes traditionnelles d'énergie (non-commerciales) a diminué graduellement et les formes commerciales modernes d'énergie se sont accrues d'une manière constante. La préférence pour les formes commerciales d'énergie a eu pour résultat l'accroissement rapide de la demande et le taux de croissance de la consommation énergétique commerciale a surpassé la croissance totale de l'économie. Alors que I Inde a été capable de s'approvisionner en pétrole sans trop de difficulté par des moyens de production indigéne et d'importations, des problèmes de balance de paiements sont survenus à cause de l'augmentation aiguë de la facture énergétique. Une stratégie globale en matière d'énergie a été formulée pour inclusion dans le sixième plan quinquennal, ce qui assurera des approvisionnements en energie adéquats pour faire face aux exigences énergétiques à court terme tout en gardant en vue les objectifs à long terme. Le plan envisage d'atteindre un équilibre entre l'offre et la demande en matière d'énergie à court et moyen termes en accélérant l'exploitation des ressources énergétiques conventionnelles du pays et en contrölant la demande par des mesures appropriées. A long terme, la base de la stratégie du développement en matière d'énergie consiste en l'exploitation des ressources énergétiques nouvelles et renouvelables. La escena energética de la India a sufrido un cambio marcado durante las últimas tres décadas. En general la dependencia en la energia no comercial a declinado gradualmente mientras que el uso de recursos de energia comercial ha aumentado continuamente. Esto ha generado una rápida tasa de creamiento de la demanda de energia comercial que supera la tasa de crecimiento económico. A pesar de que la India pudo satisfacer sus necesidades de petróleo mediante producción propia e importaciones hay problemas en la balanza de pagos. Se ha formulado estrategia general para el Sexto Plan Quinquenal que asegurará el suministro en el corto plazo sin descuidar la perspectiva a largo plazo. El plan prevee obtener el balance de la oferta y la demanda en el corto y mediano plazo mediante una exploración acelerada y una apropiada administración de la demanda. Para el largo plazo, la explotación de recursos nuevos y renovables de energia es la base de la estrategia de desarrollo energético.