Water Control Measures Research Articles

Surface Water Control for Mining Thick, Relatively Shallow Coal Seams in the Loess Area of Western China

Disastrous surface water incursions can easily occur during mining in the loess area of western China because of the shallow depth and great thickness of the coal seams there. Effective water control and drainage measures are essential to prevent such disasters. Using panels 90102 and 90103 of the Antaibao Mine of the Pingshuo mining area, Shanxi Province, as a case study, we analyzed the causes of the problem and the risk of surface water infiltration. Based on the vertical zoning features of the predicted deformation of the overburden strata and ground movement, the water-conductive fracture zone was 149.7 m thick, which means that mining could induce the inrush of surface water into the mining areas. A comprehensive set of methods was proposed, including excavation of drainage ditches, backfilling of subsiding areas, and construction of underground drainage channels. While these modifications were made in response to the geological and topographical conditions and surface drainage patterns of this site, similar methods can be used for other mines in loess areas.

Mapping the Gap of Water and Erosion Control Measures in the Rapidly Urbanizing Mbezi River Catchment of Dar es Salaam

In rapidly urbanizing catchments, increase in stormwater runoff may cause serious erosion and frequent floods if stormwater management systems are improper and dysfunctional. Through GIS-based modelling, field investigations, resident’s questionnaire survey, and interviews with officials, the study set out to assesses the coverage and efficiency of drainage infrastructure in Mbezi River catchment basin in Dar es Salaam, Tanzania. Between 2003 and 2016, the catchment imperviousness increased by 41%, causing flood incidents, massive erosion, and numerous pollution sources. Residents strive to address stormwater hazards using terraces, hedges, and physical barriers; however, the problems persist, indicating lack of coordination and poor causality understanding between land-use changes and catchment impacts. Small-scale stormwater harvesting was exercised by 75% of the households, pointing to water supply challenges. Municipal stormwater management efforts was limited to roadside drains covering 17% of road lengths in the catchment, and 65% of those did not meet their design standards. Interviews with officials revealed a need for improved co-understanding and collaborative initiatives to bolster integrated water management. The study suggests a need to adopt a new urban stormwater management paradigm, appropriate for both residents and authorities. Without this new discourse, the urbanization led stormwater increase might jeopardize the liveability of the entire catchment.

Influential factors and control of water inrush in a coal seam as the main aquifer

In this paper, a combination of field measurement, theoretical analysis and numerical simulation were used to study the main control factors of coal mine water inrush in a main aquifer coal seam and its control scheme. On the basis of revealing and analyzing the coal seam as the main aquifer in western coal mine of Xiao Jihan coal mine, the simulation software of PHASE-2D was applied to analyze the water inflow under different influencing factors. The results showed that water inflow increases logarithmically with the coal seam thickness, increases as a power function with the permeability coefficient of the coal seam, and increases linearly with the coal seam burial depth and the head pressure; The evaluation model for the factors of coal seam water inrush was gained by using nonlinear regression analysis with SPSS. The mine water inrush risk evaluation partition within the scope of the mining field was obtained, through the engineering application in Xiao Jihan coal mine. To ensure the safe and efficient production of the mine, we studied the coal mine water disaster prevention and control measures of a main aquifer coal seam in aspects of roadway driving and coal seam mining.

Prevention of Groundwater Disasters in Coal Seam Floors Based on TEM of Cambrian Limestone

We analyzed the abundance and connectivity of Cambrian limestone aquifers (CL) using data from geological and hydrogeological boreholes, groundwater tracer tests, groundwater temperature monitoring, and surface transient electromagnetic exploration (TEM). Our results demonstrate that extremely well-developed small faults with an average density of number 73 per square km control the groundwater abundance and flow of the CL. The hydraulic conductivity of the CL aquifers estimated by tracer tests lies between 13,511 and 38,738 m/d, suggesting good connectivity. The surface TEM result of 4.91 km2 shows that areas with an apparent resistivity value less than 30 Ωm can be treated as an anomalous low-resistivity zone. This has been proven to be reliable by experience at the working face and can be used to determine water control measures for future mining. Using these data, we developed a series of preventive measures to mitigate potential floor water ingress related to future mining in the eastern area of the Pingdingshan coalfield No. 2 mine.

A hydraulic invariance‐based methodology for the implementation of storm‐water release restrictions in urban land use master plans

AbstractA hydraulic invariance (HI)‐based methodology was developed as a tool to support implementation of storm flow control measures into land use master plans (LUMPs) for urban catchments. The methodology is based on the use of simple hydrologic analysis to compare predevelopment and postdevelopment catchment flow release scenarios. Differently from previous literature examples, for which the parcel scale is usually considered for the analysis, HI was pursued assuming the LUMP areas of transformation as the basic units for assigning storm water control measures in the form of flow release restrictions. The methodology was applied to a case study catchment in the southern part of the City of Catania (Italy), for which the LUMP re‐design has been recently proposed. Simulations were run based on the use of the EPA‐Storm Water Management Model and allowed deriving flow release restrictions in order to achieve HI at the subcatchment level for design events of different return period.

Bioretention storm water control measures decrease the toxicity of copper roof runoff.

The present study evaluated the ability of 2 different bioretention storm water control measures (SCMs), planter boxes and swales, to decrease the toxicity of sheet copper (Cu) roofing runoff to Daphnia magna. The present study quantified changes in storm water chemistry as it passed through the bioretention systems and utilized the biotic ligand model (BLM) to assess whether the observed D. magna toxicity could be predicted by variations found in water chemistry. Laboratory toxicity tests were performed using select storm samples with D. magna cultured under low ionic strength conditions that were appropriate for the low ionic strength of the storm water samples being tested. The SCMs decreased toxicity of Cu roof runoff in both the BLM results and the storm water bioassays. Water exiting the SCMs was substantially higher than influent runoff in pH, ions, alkalinity, and dissolved organic carbon and substantially lower in total and dissolved Cu. Daphnids experienced complete mortality in untreated runoff from the Cu roof (the SCM influent); however, for planter and swale effluents, survival averaged 86% and 95%, respectively. The present study demonstrated that conventional bioretention practices, including planter boxes and swales, are capable of decreasing the risk of adverse effects from sheet Cu roof runoff to receiving systems, even before considering dilution of effluents in those receiving systems and associated further reductions in copper bioavailability. Environ Toxicol Chem 2017;36:1680-1688. © 2016 SETAC.

Human adaptation to mid- to late-Holocene climate change in Northeast Thailand

This article integrates palaeoenvironmental and archaeological sequences covering the mid- to late-Holocene in Northeast Thailand. The former reveal the fluctuating intensity of the Asian summer monsoon, leading to periods of higher moisture availability with intervals of relative aridity. The latter are founded on a series of new radiocarbon determinations that provide a basic chronological framework, from the initial Neolithic settlements by rice farmers (c. 3700 cal. BP) to the end of the prehistoric Iron Age around 1300 cal. BP. By dovetailing the two, we find that periods of relative aridity occurred during the later Iron Age as an agricultural revolution witnessed water control measures, plough and irrigated rice cultivation and a marked rise in social elites. The correlation between climatic and cultural changes is found to continue into the period of the Angkorian state. Rather than cause a decline and/or abandonment of late Iron Age settlements, we find that the environmental stress caused by a weaker summer monsoon was met by a strong social response and by adaptations that generated a transition into early socially hierarchic polities.

Reliable Solution in Dynamic River Flow System Computations

Reliable Solution in Dynamic River Flow System Computations Application and limitation of various computational methods handling hydrologic runoff and varied unsteady river flow equations was studied here. Investigations were focused on many numerical aspects linear, non-linear solution of continuity and dynamic equations. A river catchment was examined, hydrometric stations, water control measures at upstream and hydrodynamic systems of river- reservoir at downstream were modeled provided evaluation and performance of water conveyance systems proposed for water resources planning and management. Application of modeling flow discharge in rivers was reviewed through a number of flow routing techniques. These classical computational methods have been widely used in water resources engineering and are subject of front line research by hydrologic and hydraulic modelers. Application of conventional and practical methods such as Muskingum-Cunge which are classified under hydrologic and hydraulic routing categories was examined for nonlinear variation of hydrodynamic parameters. Several methods including various numerical schemes were used and compared for modeling accurate unsteady flows computations. Analysis were ranked based on four criterions (consistency, stability, convergence and accuracy) examined with field observations and recorded data. Result of analysis verified that with careful description of constant and variable parameters involved in the Muskingum-Cunge model, the nonlinear terms and physical behavior of the problem was best fitted as compared by developed numerical solutions. The kinematic wave model and Hydrologic Engineering Centre (HEC) and Danish Hydraulic Institute (DHI) Mike series software were employed to verify developed fully dynamic wave model. A 42 kilometer reach length (a location between two hydrometric stations) was modeled with hydrologic and hydro-informatics parameters in Kor River were used. Comparing performances of two constant and variable Muskingum-Cunge methods, nonlinear model with variable parameters had highest reliability and accurately was used for dynamic water wave routing in water conveyance systems (especially for rivers without measuring gage stations).

Water Quality Change and Control Measures of Landscape River on West Campus of University of Jinan, China

on the basis of inflow calculation and water quality monitoring of Jiazi river, the present quality situation of landscape river in University of Jinan was evaluated, with the indicator of nitrogen, by arithmetic means method which was usually used for environment quality evaluation of surface water. In addition, the river dilution mixture model was built for water quality simulation with the indicator of ammonia nitrogen. Moreover, the relevant control measures of aquatic plants restoration technologies and dam reconstruction were proposed to improve the landscape river water quality.

Comparison of Runoff Quality and Quantity from a Commercial Low-Impact and Conventional Development in Raleigh, North Carolina

Urbanization and its associated increased impervious footprint lead to stream impairment through erosion, flooding, and augmented pollutant loads. Low-impact development (LID) focuses on disconnecting impervious areas, increasing infiltration and evapotranspiration, and treating storm water on site through the use of storm water control measures (SCMs). In this study, a conventional development (centralized storm-water management) and an adjoining infiltration-based LID commercial site in Raleigh, North Carolina, were compared with respect to hydrology and water quality. The conventional development [2.76 ha, 61% directly connected impervious area (DCIA)] and the LID (2.53 ha, 84% DCIA) had underlying hydrologic soil group B soils. The LID was treated by a mix of green (aboveground) and grey (underground) infrastructure including an underground detention chamber and infiltration gallery, underground and aboveground cisterns, and aboveground swales and bioretention; the conventional development was treated with a dry detention basin and swales. Inflow and outflow runoff volumes and peak flows were normalized by DCIA. For the 47 hydrologic storms monitored, runoff coefficients of 0.02 at the LID site and 0.49 at the conventional site were recorded. The conventional development had an 11-fold higher median peak flow rate than the LID site. For the three storms more intense than the 10-year, 5-min average recurrence interval (ARI) event, the conventional site Qp was an average of 7.7 times higher than that of the LID. Flow proportional, composite water-quality samples were analyzed for total nitrogen (TN), total phosphorus (TP), total Kjeldahl nitrogen (TKN), total ammoniacal nitrogen (TAN), nitrite-nitrate nitrogen (NOX), organic nitrogen (ON), orthophosphate (Ortho-P), and total suspended solids (TSS). Generally, no significant difference in pollutant event mean concentrations (EMCs) was observed between sites. For the 20 water-quality storms sampled, the LID site produced pollutant loadings that were less than 5% of those at the conventional site for all species studied. Results demonstrated highly effective and space-saving solutions when green and grey infrastructure are merged, which is often the case when constructing on high land-cost properties. The exceptional results from this LID were due to (1) an overdesigned system capable of capturing the 77-mm storm, rather than a typical 25-mm storm, and (2) the high infiltration capacity of the type B soils coupled with a high driving head (∼3 m).

Maintenance versus Maturation: Constructed Storm-Water Wetland’s Fifth-Year Water Quality and Hydrologic Assessment

Constructed storm-water wetlands (CSWs) have become popular storm water control measures (SCMs) in low-lying coastal environments, offering a hybrid between larger detention practices (wet ponds) and newer green infrastructure technologies. However, it is relatively rare that CSWs are monitored once the practice has aged 4 years, causing some concern among stakeholders about the long-term performance of CSWs. The specific objective of this research was to investigate the effects that wetland maturation and lack of maintenance have on the ability of a 5-year-old CSW to mitigate hydrology and improve water quality. A CSW was monitored from 2012–2013 that had not been maintained since construction in the spring of 2007. Since then, it has established as a diverse and healthy ecosystem. The monitoring results were compared with the results of a study conducted at the same site for a 1-year period immediately following construction (2007–2008). In 2007–2008, runoff volumes were reduced 54% and peak discharges 80%; whereas in 2012–2013, no change was observed in volume, and peak discharges were reduced by 64%. The stark difference in hydrologic mitigation was attributed to less availability of design volume in 2012–2013 because of (1) organic detritus accumulation during the intervening 5 years measured to be 7 cm; (2) modest siltation; and (3) an upward water-table adjustment owing to differing average antecedent dry periods. The 2012–2013 hydrologic performance of this CSW was similar to other CSWs (that were 2 years of age) studied in North Carolina, indicating that ecological systems should be monitored for performance after the point of establishment (2–3 years) for regulatory purposes. Overall nitrogen event mean concentration (EMCs) were reduced as the wetland matured, but not for total phosphorus (TP), as the effluent concentrations increased from 2007–2008 to 2012–2013. CSW maturation seemed to outweigh the lack of maintenance for both nitrogen treatment and stabilization of internal sediment. Maintenance (removal/replacement of forebay sediments and detritus material) need was apparent, however, for TP treatment and hydrologic mitigation. This appeared to be the only form of maintenance that would have been needed in the last 6 years for an SCM treating a 47-ha watershed. In comparison to the other practices, namely bioretention and permeable pavement, similar CSWs may have much lower operation and maintenance costs. This may make CSWs a viable option in areas where little resources exist for SCM maintenance.

Effects of Runoff Characteristics and Filter Type on Geotextile Storm Water Treatment

Urban storm water runoff carries particulate matter and other pollutants to water bodies, causing environmental problems. Removing suspended solids from runoff through geotextile filtration is a storm water control measure currently under investigation, which could help lessen the negative impacts of storm water on aquatic ecosystems. In this study, three geotextiles were tested in a laboratory setup with influent suspensions having hydraulic loading rates, total suspended solids (TSS) concentration, and particle-size distributions similar to those reported for urban highway storm water runoff. The results indicated that after a short priming period, all three geotextiles can effectively remove suspended solids to below a target concentration of 30 mg/L. The results also showed that influent hydraulic loading rate and TSS concentration have minimal effects on the total mass of solids captured by the filter, whereas particle-size distribution does affect the total mass of solids captured by the filters. The retention criteria for choosing the appropriate geotextile for storm water treatment established in recent literature were evaluated by using the laboratory results. The geotextiles and sand filters were directly compared by using the results of the laboratory column testing of sand filters performed for this study. The results indicate that a geotextile will outlast a sand filter in terms of total solids loading under similar conditions.

Application of the Analytic Hierarchy Process to Assessment of Water Inrush: A Case Study for the No. 17 Coal Seam in the Sanhejian Coal Mine, China

Disasters caused by water inrush affect many coal mines in China. In order to predict and prevent water inrushes during mining of the no. 17 coal seam in the Sanhejian coal mine, the factors that affect water inrush from the underlying Ordovician limestone were studied using the analytic hierarchy process (AHP). The AHP method is based on the geographic information system, through which the sub-thematic layer and the overlying layers of each dominating factor were constructed. An expert system was used to calculate weighting for each factor. Integration of the controlling factors through the AHP allowed us to develop a vulnerability index map in which the mining area was divided into different zones according to the risk level for water inrush during mining. Furthermore, water control measures were recommended in response to each risk level.

Increasing Stream Geomorphic Stability Using Storm Water Control Measures in a Densely Urbanized Watershed

This study used previously established unit critical discharges, annual allowable erosional hours, and annual allowable volume of eroded bed-load standards to evaluate two types of storm water control measures (SCMs): low-impact development (LID) practices and a large detention SCM (wet pond). Nine initial scenarios modeled in PC Storm Water Management Model (PCSWMM) incorporated different combinations of wet ponds, green roofs, rainwater harvesting systems, permeable pavement, and rain gardens to determine the best scenario for reducing stream erosion potential within a highly urbanized watershed in Chapel Hill, NC. The best-case scenario to reduce annual erosional hours and eroded bed load within the stream consisted of an aggressive utilization of LID practices in combination with an undersized wet pond. Although this scenario did not meet the annual erosional hour standard for rural reference streams, 0.35 h/ha/year, it did reduce erosional hours and eroded bed-load sediment by factors of 2.4 and 2.5, respectively, improving the existing condition. An alternative wet pond outlet structure that used two elevations of small drawdown orifices was explored to determine if current wet pond design practices could be improved to include stream stability. The new configuration provided a modest reduction in the number of erosional hours, a factor of 1.3, but increased the volume of eroded bed load by a factor of 1.2 when compared with the normal wet pond. However, adding widespread LID practices to the alternative outlet design reduced erosional hours and bed load transport by factors of 1.8 and 1.2, respectively, when compared with the normally configured wet pond. The failure to meet the erosional standards in all scenarios demonstrated the difficulty of requiring highly urbanized watersheds (60% impervious) to meet such strict stream protection measures.

Effect of Urban Catchment Composition on Runoff Temperature

AbstractUrban runoff adversely impacts cold-water stream environments due to sporadic fluxes of thermally enriched runoff. This adversely impacts tourism in regions that support trout and salmon streams. Research on storm water control measures (SCMs) has shown that meeting the 21°C trout threshold is not consistently feasible with current SCM technologies. Thus, it is important to consider other factors in storm water temperature management, such as catchment characteristics. Median and maximum runoff temperatures from a shaded parking lot were consistently lower than those from a nearby unshaded lot. This suggests the need to implement a tree canopy cover in trout-sensitive catchments. A light-colored chip seal pavement was compared to a traditional hot-mix asphalt pavement; the light-colored chip seal produced median storm water temperatures that were 1.4°C lower than the standard hot-mix asphalt. It was shown that runoff temperature measurement location is critical when evaluating SCM performance, and...

Effect of low temperature on reservoir water and mechanical control measure

大型水库低温水下泄对农业生态和水生生态产生较大不利影响, 国内在高坝大库设计中多采用叠梁门表层取水结构来获取满足农作物的灌溉水温和鱼类生活史需求水温, 其运用的下泄水温调节效果多采用立面二维或垂向一维水温模型进行模拟。文中利用MIKE3软件建立研究水库的三维水温数学模型, 精确模拟水库采用叠梁门分层取水和单层进水口两种取水方案下的水库水温结构及下泄水温。预测结果表明叠梁门分层取水方案能有效地提高水库泄水温度, 3~9月出现的水库低温水温度比单层进水口提高2~4 ℃, 并在5月份就能达到鱼类产卵要求的18.4 ℃。叠梁门分层取水结构能够有效地提高水库泄水温度, 最大程度减缓水库低温水下泄的生态影响, 实现生态环境保护和经济效益的较好协调, 叠梁门结构比较适合作为国内生态友好型大型水库工程建设的生态修复和保护措施。

Harvestable Nitrogen Accumulation for Five Storm Water Wetland Plant Species: Trigger for Storm Water Control Measure Maintenance?

As the use of constructed storm water wetlands to treat storm water runoff becomes more frequent, strategies for maintaining or increasing their pollutant removal over time must be examined. One potential strategy is plant harvesting at the water surface to remove nutrients that would otherwise be deposited back into the wetland during senescence. This technical note presents a first look at this strategy from a storm water management perspective. Vegetation was harvested from two storm water wetlands located in Smithfield and Pactolus, North Carolina, to evaluate the ability of five wetland plant species to sequester nitrogen. Biomass samples were collected from the following species of emergent vegetation: Pontederia cordata (Pickerelweed), Saururus cernuus (Lizard Tail), Scirpus cyperinus (Wool Grass), Sagittaria latifolia (Arrowhead), and Schoenoplectus tabernaemontani (Softstem Bulrush). Samples were collected immediately prior to senescence in September and October 2007 and analyzed for nitrogen content on a percent of biomass basis. At the Pactolus wetland the Pontederia cordata, Scirpus cyperinus, and Schoenoplectus tabernaemontani biomass retained significantly (p<0.05) more nitrogen than Sagittaria latifolia and Saururus cernuus. At the Smithfield wetland, Pontederia cordata and Sagittaria latifolia biomass retained significantly more nitrogen than Scirpus cyperinus and Saururus cernuus. Wetland maturity appears to have a direct relationship to harvestable nitrogen, which could explain why the relative amount of nitrogen sequestered in Scirpus cyperinus and Sagittaria latifolia varied between the two wetlands. A positive relationship existed between the density of harvested biomass and nitrogen removal for two species. To estimate the relative amount of harvestable nitrogen, a model for estimating total nitrogen loading in Coastal Plain watersheds in North Carolina was used to compare estimated inflow nitrogen mass to that which could theoretically be harvested. The harvestable N mass was greater than 20% of inflow nitrogen on an annual basis. Storm water wetland plant harvesting as a maintenance activity has potential to supplement wetland nitrogen removal.

Mapping the irrigated rice cropping patterns of the Mekong delta, Vietnam, through hyper-temporal SPOT NDVI image analysis

Successful identification and mapping of different cropping patterns under cloudy conditions of a specific crop through remote sensing provides important baseline information for planning and monitoring. In Vietnam, this information is either missing or unavailable; several ongoing projects studying options with radar to avoid earth observation problems caused by the prevailing cloudy conditions have to date produced only partial successes. In this research, optical hyper-temporal Satellite Pour l'Observation de la Terre (SPOT) VEGETATION (SPOT VGT) data (1998–2008) were used to describe and map variability in irrigated rice cropping patterns of the Mekong delta. Divergence statistics were used to evaluate signature separabilities of normalized difference vegetation index (NDVI) classes generated from the iterative self-organizing data analysis technique algorithm (ISODATA) classification of 10-day SPOT NDVI image series. Based on this evaluation, a map with 77 classes was selected. Out of these 77 mapped classes, 26 classes with prior knowledge that they represent rice were selected to design the sampling scheme for fieldwork and for crop calendar characterization. Using the collected information of 112 farmers’ fields belonging to the 26 selected classes, the map produced provides highly accurate information on rice cropping patterns (94% overall accuracy, 0.93 Kappa coefficient). We found that the spatial distributions of the triple and the double rice cropping systems are highly related to the flooding regime from the Hau and Tien rivers. Areas that are highly vulnerable to flooding in the upper part and those that are saline in the north-western part of the delta mostly have a double rice cropping system, whilst areas in the central and the south-eastern parts mostly have a triple rice cropping system. In turn, the duration of flooding is highly correlated with the decision by farmers to cultivate shorter or longer duration rice varieties. The overall spatial variability mostly coincides with administrative units, indicating that crop pattern choices and water control measures are locally synchronized. Water supply risks, soil acidity and salinity constraints and the anticipated highly fluctuating rice market prices all strongly influence specific farmers’ choices of rice varieties. These choices vary considerably annually, and therefore grown rice varieties are difficult to map. Our study demonstrates the high potential of optical hyper-temporal images, taken on a daily basis, to differentiate and map a high variety of irrigated rice cropping patterns and crop calendars at a high level of accuracy in spite of cloudy conditions.

Effectiveness of LID for Commercial Development in North Carolina

AbstractThe purpose of this project was to characterize runoff and pollutant export from three commercial sites: one with no storm water control measures (NoTreat), one with a wet detention basin (WetBasin), and one with low impact development (LID) measures. The sites were located in the Piedmont and Coastal Plain physiographic regions of central North Carolina. Rainfall, runoff, and pollutant concentrations were monitored at each site for more than one year by using automated rain gauges and samplers. The storm event mean concentrations (EMCs) of total kjeldahl nitrogen (TKN), nitrate+nitrite nitrogen (NOx-N), and total phosphorus (TP) in runoff were generally less than corresponding EMCs for many other urban areas in the United States. Also, EMCs were similar to those found for eight parking lots in North Carolina. Storm runoff to rainfall ratio was greatest for the NoTreat site and least for the WetBasin site, which was anticipated because the NoTreat site had no detention/storage and the WetBasin sit...

Indicator Bacteria Performance of Storm Water Control Measures in Wilmington, North Carolina

Indicator bacteria are a common source of impairment in surface waters in the United States. Urban storm water runoff has been identified as a contributor to elevated indicator bacteria concentrati...