Gradient Self-Potential Logging in the Rio Grande to Identify Gaining and Losing Reaches across the Mesilla Valley

The Rio Grande/Río Bravo del Norte (hereinafter referred to as the “Rio Grande”) is the primary source of recharge to the Mesilla Basin/Conejos-Médanos aquifer system in the Mesilla Valley of New Mexico and Texas. The Mesilla Basin aquifer system is the U.S. part of the Mesilla Basin/Conejos-Médanos aquifer system and is the primary source of water supply to several communities along the United States–Mexico border in and near the Mesilla Valley. Identifying the gaining and losing reaches of the Rio Grande in the Mesilla Valley is therefore critical for managing the quality and quantity of surface and groundwater resources available to stakeholders in the Mesilla Valley and downstream. A gradient self-potential (SP) logging survey was completed in the Rio Grande across the Mesilla Valley between 26 June and 2 July 2020, to identify reaches where surface-water gains and losses were occurring by interpreting an estimate of the streaming-potential component of the electrostatic field in the river, measured during bankfull flow. The survey, completed as part of the Transboundary Aquifer Assessment Program, began at Leasburg Dam in New Mexico near the northern terminus of the Mesilla Valley and ended ~72 kilometers (km) downstream at Canutillo, Texas. Electric potential data indicated a net losing condition for ~32 km between the Leasburg Dam and Mesilla Diversion Dam in New Mexico, with one ~200-m long reach showing an isolated saline-groundwater gaining condition. Downstream from the Mesilla Diversion Dam, electric-potential data indicated a neutral-to-mild gaining condition for 12 km that transitioned to a mild-to-moderate gaining condition between 12 and ~22 km downstream from the dam, before transitioning back to a losing condition along the remaining 18 km of the survey reach. The interpreted gaining and losing reaches are substantiated by potentiometric surface mapping completed in hydrostratigraphic units of the Mesilla Basin aquifer system between 2010 and 2011, and corroborated by surface-water temperature and conductivity logging and relative median streamflow gains and losses, quantified from streamflow measurements made annually at 16 seepage-measurement stations along the survey reach between 1988 and 1998 and between 2004 and 2013. The gaining and losing reaches of the Rio Grande in the Mesilla Valley, interpreted from electric potential data, compare well with relative median streamflow gains and losses along the 72-km long survey reach.

Appropriate Discharge from Diversion Dam to Dilute High Concentrated Community Wastewater of Riverbank Settlements along Phetchaburi River in Phetchaburi Province, Thailand

The research was focused on determining dilatability of traveling mass water from Phetchaburi diversion dam on high concentrated community wastewater that flowing into Phetchaburi river. The mass water quality was sampled at six-consecutive measuring stations from Phetchaburi diversion dam to the river mouth with various distances of traveling, and analyzed for 27 environmental indicators before employing ANOVA ANALYSIS which resulted with highly significant differences between indicator and station only BOD, COD, TSS, and turbidity. When the linear regression was employed to determine both the water quality indicators in relation to discharges (10, 15, 20, and 25 cms.) and the traveling distances, resulting the determination coefficients of 0.93 for BOD, 0.80 for COD, 0.83 for TSS, and 0.50 for turbidity. Only BOD value is included in the list of surface water quality standards. After employing the derived equations to calculate BOD in comparison with observed value, then it was chosen to support the decision of required BOD for 3 mg/L at Muang Municipal bridge together with discharge of 10-15 cms from Phetchaburi diversion dam. If more or less this range in summer period, the dilatability of high contaminant concentration was decreased 2-10 folds due to less mass water flow and washing off organic and solid wastes from flooding along the riverbanks. Furthermore, the traveling mass water from diversion dam is possibly eligible to dilute the high concentrated wastewater from dense and populated community but the diluted mixture depending on the amount and concentration of wastewater inflow.An abstract is a brief, comprehensive summary of the contents of the article, it allows readers to survey the contents of an article quickly and, like a title, it enables persons interested in the document to retrieve it from abstracting and indexing databases. Most scholarly journals require an abstract. Consult the instructions to authors or web page of the journal to which you plan to submit your article for any journal-specific instructions. A well-prepared abstract can be the most important single paragraph in an article. Most people have their first contact with an article by seeing just the abstract, usually in comparison with several other abstracts, as they are doing a literature search. Readers frequently decide on the basis of the abstract whether to read the entire article. The abstract needs to be dense with information. By embedding key words in your abstract, you enhance the user’s ability to find it. Do not exceed the abstract word limit of the journal to which you are submitting your article. Word limits vary from journal to journal and typically range from 150 to 250 words. For information on how abstracts are used to retrieve articles, consult Record Structure for APA Databases

Urban Ecological Benefit Evaluation by Diversion Dam Based on Comprehensive Ecological Assessment Index System

The comprehensive ecological index system for cities of Jilin Province was formed by mean square difference method to analyze the annual level of social development, ecological and environmental development, economic development and comprehensive ecological environment for 4 eco-polluted cities (Jiutai, Dehui, Dunhua, Yanji) during 2002-2012. Then the effect on improving urban ecological environment by building diversion dam was evaluated quantitatively for each city. The comprehensive ecological index values of cities had all represented a smooth upward tendency except a marked growth in 2007. The diversion dam could significantly promote the comprehensive urban ecological environment level for cities of Jiutai, Dunhua and Yanji, but not for the city of Dehui.