World Environmental and Water Resources Congress 2020: Groundwater, Sustainability, Hydro-Climate/Climate Change, and Environmental Engineering

Currently, nutrients are not removed by standard wastewater treatment processes. Constructed wetlands placed after conventional wastewater treatment may be one way to remove nutrients before wastewater flows to receiving waters. To evaluate the effectiveness of constructed wetlands on nutrient removal, 5 constructed wetlands with varying amounts of sandy loam, compost, and shredded bark were tested. The same three plant species were planted in each wetland. Treated wastewater was placed in each planter and samples were taken after 2, 3, 4, 5, and 7 days. On average, total phosphorus increased by 289%, phosphate increased by 130%, total nitrogen decreased by 70%, nitrate increased by 23%, and ammonia decreased by 83%. The only nutrient impacted by residence time was ammonia where a peak residence time was achieved after 2–4 days. Soil mixture impacted total phosphorus, total nitrogen, and ammonia; the planters with 20% or less compost retained more nutrients than the planters with 30–40% compost. Leach test data suggests that the increase in total phosphorus and phosphate were caused by leaching of organic material present in the compost. Results show that constructed wetlands effectively remove nitrogen, but do not effectively remove phosphorus with the soil mixtures tested in this study.

This study examines urban runoff at a residential site in southern California, which receives imported water from northern California that is isotopically distinct from locally recharged water sources. Stable water isotopes have been used in previous studies to determine percentages of imported water in local urban streams in southern California, but previous studies used pure imported tap water as the endmember mixing source. By sampling urban runoff in street gutters derived from lawn watering and comparing to tap water, this study provides a better understanding of water isotope signatures in imported water as a mixing source in urban streams. Stable water isotopes show modest-moderate evaporation enrichment between irrigation source water and lawn runoff, suggesting tap water endmember may be used with modest error to assess mixing between imported water runoff and local groundwater baseflow in urban streams. Runoff from urban sources often contribute significant amounts of nutrients that can negatively impact waterways. Previous studies in southern California are conflicting as to the source of nutrients, whether they are geologic or anthropogenic. For this study, the site is fertilized and then monitored weekly for one year to measure nutrient content in runoff without additional fertilization. The study sheds light on sources of nutrients in local urban streams and provides constrained information on lawn runoff as a factor in elevated concentrations of nutrients.

Commercially available water-quality monitoring systems are often cost prohibitive for water-resource professionals. The goal of this project is to develop a low-cost, compact, and mobile water-quality datalogging system deployable for short or long operations. The system aims to be as flexible and serviceable as possible, even for users with limited experience with programming and/or electronics. Low-cost, and off-the-shelf or 3D printed components enhance the transferability, customization, and platform’s ease-of-maintenance. The GatorByte currently uses the Particle family of Arduino compatible cellular-capable microcontrollers, open-source software, environmental sensors, GPS, SD card storage, and Bluetooth module to monitor, log, and transmit water-quality data and position periodically to a remote server over cellular network. Using off-the-shelf components along with a custom circuit board limits a unit’s cost to under $1,500. The sensing unit is complimented by a cloud-based datastore, along with web and mobile applications to visualize the data. GatorByte enables collection of water quality data at locations varying spatially in a cost-effective and reliable manner. The system’s hardware and firmware are extremely flexible allowing researchers and water-resource managers to scale and modify the system for their needs.

The storage of CO₂ in sedimentary reservoirs is one of the possible ways to alleviate the global warming caused due to the extensive emission of greenhouse gases. The concentration of CO₂ in the environment is continuously increasing and if the excess amount of CO₂ is not captured and stored, the concentration is expected to increase exponentially in the future. The excess CO₂ in the atmosphere need to be stored in deep sedimentary reservoirs. Once CO₂ is injected into the reservoir, it is mandatory to track the various associated issues like the migration of CO₂ towards the caprock, the pressure buildup, ground uplift, and faults reactivation during CO₂ injection. All of these issues need to be monitored to avoid the leakage of CO₂ from the reservoir. In this paper, a numerical modeling study is performed to model the geomechanical behavior of the deep Qasim Reservoir in Saudi Arabia. The pore pressure buildup and ground uplift was calculated during CO₂ injection into the reservoir. The reservoir stability analysis was performed using Mohr-Coulomb failure criterion.

Groundwater is one of the important hydrological cycles that has a major role in balancing the ecosystem. The drastic change in climate in the twenty-first century has adversely affected the groundwater storage (GWS), later the hydrological cycle. The limited availability of groundwater data poses difficulty to investigate the effects of changing the climate on GWS. This research addressed the impact of climate variability in GWS variability in Northern India. The underlying goal was to assess the relationship between GWS and climate variability. Here, El Niño-Southern oscillation (ENSO) was used as an indicator of long-term climate change which can be categorized into three climatic phases—El Niño, La Niña, and neutral phases. Gravity recovery and climate experiment (GRACE) derived GWS anomaly was calculated to understand groundwater temporal variability as an effect of ENSO phases. Pearson correlation analysis was done to assess the relationship between GWS, precipitation, and ENSO. A significant positive correlation was observed between precipitation, GWS, and ENSO. A decreasing trend in GWSA was observed. Increased storage during La Niña and relatively less groundwater storage during El Nino were observed. This study highlights the research gap between GWS and climate variability. A better understanding of the climatological effect on GWS might be more useful to water managers in addressing the complex issues related to groundwater management.

Many communities in arid and semi-arid areas rely on groundwater for drinking water. However, anthropogenic activities such as the use of fertilizers and human waste disposal impose the risk of nitrate pollution to the aquifers. With over 8.5 million population, Tehran, the capital of Iran, has experienced rapid population growth during the past decades while the majority of the city did not have a sewerage network and the main way of wastewater disposal was individual cesspits inside houses. The long-term discharge of raw wastewater in cesspits has increased nitrate concentration in the Tehran aquifer which serves as a source of one-third of drinking water for the city. Although the construction of a sewerage network seems vital for improving the groundwater quality, one of the main concerns of this network is the drawdown of the water table in aquifer due to reduced recharge. A dynamic mass-balance model is developed for simulating water quantity and nitrate concentration in Tehran aquifer in order to study the impacts of sewerage network on the quantity and quality of groundwater. Considering that the sewage disposal in cesspits is one of the main sources of recharge, the results show the construction of sewerage network does not necessarily result in a reduction of nitrate concentration in long-term. This seems to be mainly because the reduced aquifer recharge results in groundwater depletion and the depleted aquifer is more prone to pollution even with smaller amounts of pollutants. Based on this modeling approach, we suggest that the reduced recharge due to construction of sewerage network should be compensated by either reduction of groundwater withdrawal or managed artificial recharge. The results of this study can provide a step toward application of sustainable water resources management in arid and semi-arid areas where the cesspits and septic tanks are common for wastewater disposal.

Coastal aquifers usually act as a source of freshwater received from terrestrial sources and supplied to the overlying estuaries in the form of submarine groundwater discharge (SGD). Those aquifers act also as a sink of salt fluxes received from the estuary. Heavier saline estuarine water underlain by a less dense terrestrial-based fresh groundwater results in an unstable flow and salt transport condition. Exchange of freshwater and saline fluxes between the aquifer and the estuary may have significant impacts on the estuarine ecosystem and therefore, it is important to be understood. Two numerical models were developed using SEAWAT to study the behavior of SGD and salt exchange at two transects across the Indian River Lagoon. Field data revealed that the normalized IRL salinity can vary from freshwater salinity of 0.3 to that of ocean salinity of 1, based on ocean salinity of 35 g/L. Results obtained from model simulations showed that a transition mixing zone of brackish water exists below the estuary. Salt fluxes are found to migrate from the estuary down into the aquifer even though SGD is discharging upward from the aquifer into the lagoon. Higher IRL salinity was found to cause more salt transported into the aquifer and lower SGD into the lagoon. Regression analysis revealed a straight-line correlation (r² =1) between increasing IRL salinity and decreasing SGD. Spatial distribution of the SGD below the lagoon obtained from the numerical models showed that the SGD occurs across the entire transect with the majority being received from the mainland.

Typical values of diffusion coefficients used to model salt transport under stable conditions cannot be used to model salt transport under unstable conditions since unstable flow also includes the effect of gravity and fingering. Diffusion coefficients used under unstable conditions are usually termed as apparent diffusivity (D). This study determines the apparent diffusivity for salt transport in a saturated porous media (sandy soil, hydraulic conductivity=7.6 m/d), under unstable conditions, by comparing numerically simulated and laboratory measured source depletion curves at the salt source in a semi-infinite, homogeneous, and isotropic porous media. The measured source depletion curves were obtained through eight experiments, conducted over 12 to 15 days, using a rectangular Plexiglass model (1.80 m, 0.61 m, 0.61 m) in which a saline solution was placed over the porous media saturated with freshwater. The initial salt concentrations in the source area ranged from 4.5 kg/m³ to 36 kg/m³ while the source height ranged from 4.5 cm to 11.70 cm. The salt concentrations within the source were periodically measured using a YSI salinity meter. The numerical modeling was conducted using a three-dimensional SEAWAT model. The values of the apparent diffusivity were changed in the numerical model until the numerically simulated source depletion curves matched the laboratory measured curves. The apparent diffusivity values ranged from 2.026*10-09 to 4.282*10-08 m2/s. Analysis showed that there is a direct linear correlation between the initial salt concentration, the source height, and apparent diffusivity (D).

This paper reviews environmental and hydrological problems associated with long term climate change and flow capacity in arid groundwater basins. Flow capacity is defined as the maximum amount of water that a flow system can transmit. The phrase “rejected recharge” typically is applied to an aquifer at flow capacity where precipitation infiltration or other sources of potential recharge exceed the capacity of the saturated zone to accept additional recharge. Usually this results in regional saturation of the water table near land surface. The characteristics of a flow system that influence flow capacity are moisture availability, slope of the terrain, and permeability of the aquifer. Moisture is not available for flow capacity to be established in most arid aquifers. Climate change as a result of global warming or cooling may cause an arid system to reach flow capacity. Paleohydrologic evidence of flow capacity in arid aquifers is observed in the southwestern Basin and Range Province. Flow capacity was established in some of these aquifers during the pluvial periods of the late Pleistocene Epoch, when precipitation was higher. Recent concerns about global warming and climate change intensify concerns about possible effects of flow capacity on groundwater quality. Abandoned landfills and radioactive waste and other long term disposal sites could become inundated, creating a potentially threatening environmental problem. In addition, where flow capacity was achieved along basin floors several thousand years ago, basin floor salts were precipitated in phreatic playas. Playa salts may remain in soils and may not be completely leached for tens of thousands of years as climate becomes drier and as water tables fall. These salts can be long term sources of salinity enrichment in groundwater basins due to leaching. Hydrologists often focus on deeper sources of salinity in groundwater basins and should recognize historical presence of phreatic playas that may be a more prominent source of salinity.

During in situ remediation of contaminated groundwater, a chemical or biological amendment is introduced into a contaminant plume to react with and degrade the contaminant. Since the degradation reactions only occur where the amendment and the contaminant are sufficiently close, the success of in situ remediation is controlled by the degree to which the amendment spreads into the contaminant plume. Spreading is defined as the reconfiguration of the plume geometry, which occurs as a result of spatially and temporally varying flow fields. Spreading can occur passively due to spatially varying velocity caused by aquifer heterogeneity. Spreading can also occur actively by inducing spatially and temporally varying flow fields through injections and extractions of clean water in wells surrounding the contaminated site. We used coupled numerical investigations and laboratory experiments to explore the effects of active spreading and passive spreading on contaminant degradation. We report here on the effects of passive spreading on contaminant degradation. We analyze the features of the flow field and plume geometry that encourage spreading contaminant degradation, so that the results from the numerical investigation and experiments can be used to design active spreading pumping sequences for other aquifers with other heterogeneity patterns.

The 250 km long shallow (maximum depth of four meters) Indian River Lagoon (IRL), located on the east coast of Florida, is an estuary of varying width (0.8 km to 8 km). As a result of land use changes in the IRL watershed the IRL is becoming more eutrophic, particularly in the northern reaches where major blooms of long duration (months) are becoming more frequent. A study was conducted over a 15 month period to determine the total nitrogen (TN) and total phosphorus (TP) loads into the IRL at Eau Gallie, Florida, due to groundwater seepage from the IRL watershed. The nutrient loads were determined by multiplying the measured TN and TP concentrations by groundwater seepage determined by the finite difference model SEAWAT. The numerical model was calibrated by comparing model predicted hydraulic heads with field measured hydraulic heads. The groundwater seepages, per unit length of shoreline, ranged between 0.62 m³/day to 0.84 m³/day. The concentration ranges for TN and TP were from 0.0003 mg/l to 5.9 mg/l, and 0.044 mg/l to 0.378 mg/l, respectively. The corresponding TN and TP loads, per meter of shoreline, ranged from 554 mg/day to 2,356 mg/day, and from 60 mg/day to 99 mg/day. The assessed TN and TP loads due to groundwater showed a high level of temporal and spatial variation, and can be a significant contributor to the eutrophy within the IRL.

In situ bioremediation is the widely accepted technology for the remediation of groundwater sites contaminated with organic contaminants. However, designing an optimal in situ bioremediation system for the contaminated sites is a major challenge to the groundwater scientists. In the past, the various simulation-optimization (S/O) models have been proposed for the optimization of in situ bioremediation system. An S/O model couples the groundwater flow, contaminant, and oxygen transports simulations with an optimization algorithm. The well locations and their pumping rates are the important entities in determining the optimal in situ bioremediation cost. However, the simulation models utilized in the previous in situ bioremediation studies were mostly based on the finite difference method (FDM) and finite element method (FEM), and hence, they are only capable of locating the optimal well locations from the discretized nodes in the computational domain. In this study, we propose an S/O model where the simulator called BIOEFGM is based on the meshless element-free Galerkin method (EFGM) and it is integrated with the particle swarm optimization (PSO). BIOEFGM uses the moving least squares (MLS) approximation for computing the shape functions and hence, it provides stability in approximating the unknown variables in governing equations. In the developed S/O model, meshless BIOEFGM allows PSO to test all the locations i.e., coordinates of the discretized nodes as well of the remaining portion for the optimality. In this study, BIOEFGM-PSO model is used for the optimal in situ bioremediation of the two-dimensional aquifer site. BIOEFGM model is first verified with FEM and then used with the PSO. The selected problem is also solved with FEM-PSO model for comparing the bioremediation costs. The optimal bioremediation cost from the BIOEFGM-PSO is found to be less than that from the FEM-PSO. This study shows the advantages of using the proposed model and therefore, can be applied to the large field problems.

Frequency domain analysis of hydrological time series has been widely used to find the relations between hydrologic processes and climate variability. The periodic changes in global climate systems, occurring in periods from years to decades, can affect water resources. This study aims to find significant frequency components of the Great Lakes water level fluctuations as well as the river discharge using spectral analysis and assess their relationships through coherency analysis. Results will be a good representative of inter-annual to multi-decadal variability of natural flows in the rivers and the Great Lakes water level fluctuations. This will improve our understanding of the Great Lakes ecosystem and its natural climate variabilities. Finding the dominant frequencies of climate variability is crucial as it is still acting on our planet, and it may be more influential in the future due to the change in climate as a result of human activities. For this purpose, historical water level data of Lake Michigan along with historical streamflow data of the lake’s major inflowing rivers (Fox River, Menominee River, and Grand River) are used. Results show that, despite the changes in land use and climate in recent decades, there are still similar significant frequency components in lake water level and river discharge. This ongoing study aims to separate the natural variability of the water resources in the Great Lakes system from variations caused by external sources. This finding will insight for the Great Lakes water resources planning and management.

Analysis of changes in rainfall magnitudes is essential to obtain the temporal variation for a particular parameter. It is performed on a data set for a longer duration to quantify the variation. This paper presents an analysis of variation in rainfall at annual scale for Haridwar District, Uttarakhand, India. The monthly precipitation data is collected from the India Water Portal for the period of 1901–2002. For each individual year, the percentage change is obtained with respect to the previous year and also with respect to the long-term mean annual rainfall, for the whole period under investigation. Further, the rainfall in various decades is compared. From the results, it is found that almost 85% of the annual rainfall occurs during four months of monsoon season i.e., June, July, August, and September. The district is subjected to frequent flickering of annual rainfall. During the first five decades, the decadal average rainfall is found to be nearly same. However, anomalous behavior in annual rainfall is observed for post-1950 periods. The trend of rainfall was increasing from 1950 to 1980, whereas the last two decades of the twentieth century witnessed a sharp decrease in rainfall. Therefore, the hydro-meteorological studies with an inherent assumption of stationarity should be carried out carefully over the study area. This study may be helpful for better water resources planning and management over the district.

Water availability is one of the major issues that need attention from the present generation across the whole world to attain sustainability. Spatial variation of water resources and climatic changes are main reasons for the extremes such as droughts and floods. This urges for precise estimation of streamflow, which is typically carried out by hydrologic modelling approaches. This paper presents an application of a macro-scale hydrological model namely, variable infiltration capacity (VIC) over the Netravati River Basin, India. The water balance is modelled at a grid resolution of 0.05°x0.05°. The model was executed for the period of fifteen years i.e., 2000–2014. The period of 2000–2009 was used to calibrate the model for adjustment of the sensitive parameters affecting the discharge of the river basin. The calibrated model was validated for the duration of 2010–2014. The results reveal the model simulations to have a good compatibility with respect to the monthly observed flows. During the validation period, the Nash-Sutcliffe efficiency (NSE) and the coefficient of determination (R²) were found to be 0.71 and 0.76 respectively, justifying the applicability of the model over the basin for streamflow estimations. This study can be helpful for drought and flood monitoring as well as for implementing strategies for better planning and management.

New York City (NYC) Department of Environmental Protection (DEP) is investigating the potential impacts of future climate on the quantity and quality of NYC’s drinking water supply, and as a consequence, how these impacts could influence the operation of reservoirs within the supply system. In this study, we utilize the latest climate projections from 20 global climate models, use rigorous statistical downscaling and temporal disaggregation methods to generate climate scenarios, and use state-of-the-art modeling software system, including DEP’s operations support tool (OST) to evaluate climate change impacts. Compared with the current climate, future (mid-century) annual average air temperature is predicted to increase by 2.0°C, and precipitation by 5%. Significant trends in several climate indices, e.g., number of frost days, snowpack, and extreme rainfall events are also projected. Under these climate conditions, mean annual inflow to the Catskill/Delaware system is expected to increase by 6%, with greater increases (~25%) during December–February and a reduction (~10%) during April–June, lessening the overall seasonal variability. Although minimal change in annual average turbidities in Rondout, Schoharie, and Esopus Creeks are projected, extreme levels of turbidities could increase by >50% and such high turbidity events could be more frequent in the future. Under the projected future climate and current operating rules and assumptions, OST simulations also suggest that the average number of days the NYC water supply system is in drought conditions would remain unchanged. Furthermore, these simulations demonstrate high resiliency, high reliability, and low vulnerability of the water supply system.

The evaluation of climate change impact on hydrological cycle includes uncertainty. This study aimed to evaluate the uncertainty of climate change impact on the Zayandeh-Rud Reservoir inflow during the future 2020–2049 period. The outputs of 22 GCM models have been used under the three emission scenarios including RCP2.6, RCP4.5, and RCP8.5. The Bayesian model averaging (BMA) was used as the uncertainty analysis for weighting the outputs of 22 GCM models (precipitation and temperature) based on their ability to simulate baseline 1980–2005 period. Then the time series of equivalent precipitation and temperature were introduced to the hydrological model (i.e. IHACRES) and the output of runoff was estimated under different climate change scenarios. Results showed that different GCM models have different abilities in estimating climatic variables and the application of uncertainty analysis in climate change studies is necessary. The results showed that the winter stream flow will rise by 16 to 55% under different climate change scenarios. However, a reduction of (20–50)% is expected during spring months which complicated the regional water resource management during the following warm seasons. On the annual scale, the Zayandeh-Rud Reservoir’s Inflow will decrease (1–25)% under different emission scenarios which make the region more vulnerable to climate change than before. Therefore, adaptation strategies should be identified and some changes in Zayandeh-Rud Reservoir’s rule curve must be applied by water resource managers in the future.

Several approaches have been proposed for assessing the impacts of climate change on extreme rainfall (ER) processes at “gauged” sites but very few methods are available for linking climate change projections to the ERs at an “ungauged” location where rainfall record is limited or unavailable. Therefore, the main objective of this study is to propose an improved method that could be used for constructing reliable rainfall intensity-duration-frequency (IDF) relations at an ungauged site in consideration of climate change projections given by different climate models. The proposed approach consists of: (i) a regional-to-point downscaling to link daily regional rainfalls to daily extreme rainfalls at a given ungauged site, and (ii) a temporal downscaling using the scale-invariance GEV model to link daily-to-sub-daily extreme rainfall distributions at the same location. Results of an illustrative application using the downscaled 25-km regional rainfall data given by the climate simulations of 21 global climate models, and the observed extreme rainfall data from a network of 84 raingages located in Ontario region (Canada) have indicated the feasibility and accuracy of the proposed approach.

There exists an urgent need to assess the possible impacts of climate change on the intensity-duration-frequency (IDF) relations for improving the design of urban water infrastructure in the context of a changing climate. The main challenge is how to establish the linkages between the climate projections given by global or regional climate models at the global/regional scales and the observed extreme rainfalls at a given local site. Therefore, the overall objective of the present paper is to provide an overview of some recent progress in the development of statistical downscaling (SD) methods for linking global/regional climate predictors to the observed daily and sub-daily rainfall extremes at a single site as well as at many sites concurrently. In addition, new SD procedures are presented for describing the linkages between GCM outputs and rainfall characteristics at an ungauged location where rainfall data are limited or unavailable, a common and crucial challenge in engineering practice.

Severe water-related disasters occur almost every year in Japan due to typhoons and frontal rains; these events often lead to evacuation problem. Many real time flood forecasting systems are available in Japan, but are designed to cover the whole of Japan, and are not calibrated to local cities or rivers. The main purpose of this study was to develop a real time flood prediction model that is suitable for use at the local community level. In this study, a physical rainfall-runoff and flood inundation model was developed to predict flood inundation situations in Toyama, Japan. According to the results of the analysis, there were significant differences between the results of the simulations using DEM resolutions of 90 and 5 m. However, it should be noted that the flood inundation simulations based on the 5 m DEM take too long for real time flood prediction.

The potential impact of climate change on the effectiveness of stormwater capture facilities used for alternative water supply was examined using continuous simulation hydrologic modeling. A methodology was developed to transform future projected daily precipitation simulated from regionally downscaled global climate models (GCMs) to hourly time series. The methodology was tested on historic measured rainfall for Oakland, California, and was applied to projected future daily GCM precipitation results for two regions in California: the Monterey Peninsula and Santa Clarita, California. Hourly time series were input into an hourly continuous simulation hydrologic model framework to enable comparison of estimated stormwater facility capture under historic precipitation conditions and projected future precipitation conditions for the Monterey Peninsula region for a range of GCMs. The results of the comparison demonstrated differences in total precipitation, total water captured by facilities ranging in size and drawdown time, and the facility performance in terms of percent of average annual runoff captured.

Low lying coastal cities are under high risk of the compound flood with frequent storm surge occurrence and sea-level rise. This study attempted to develop a hybrid modeling framework to simulate various physical process of the compound flood. In this regard, first, the storm surge process is simulated using a wave-flow coupled model i.e., Delft3D-FLOW and simulated wave nearshore (SWAN). The meteorological forcing for the hydrodynamic model has been done by integrating a parametric Holland cyclone model in this framework. The urban flood process in compound flood is also simulated using a rainfall-runoff model, the storm water management model (SWMM). The case study to evaluate the performance of the modeling framework is selected as the northern Bay of Bengal and extends to surge affected areas of Chittagong coast of Bangladesh. The modeling system is employed to simulate compound flood associated with cyclone 1991 in Chittagong City. The storm surge and wave boundary conditions from the hydrodynamic model are used as downstream boundary conditions, while generated runoff from SWMM is used as a dynamic upstream boundary condition. The results showed that the compound flood modeling is sensitive to dynamic changes of storm surge height and rainfall intensity of cyclone induced rainfall. This study introduces a new modeling approach contributes to the existing knowledge of compound flood modeling and complex interactions among urban runoff process, the atmospheric process of the cyclone, and coastal storm surge.

The hydro-climatic condition over Indian region is governed by the southwest monsoon season (June to September), as a majority of annual rainfall occur in this season. The presence of flood and drought years influences the cultivation system and thus, the economy of the country as the Indian agricultural system is highly dependent on the natural rainfall. This study aims to identify the flood and drought years for the north-east Indian region from 1916 to 2015 by using sub-divisional rainfall data collected from Open Government Data (OGD) Platform of India. For this investigation, the normalized index (NI) of annual rainfall is utilized to recognize a particular year as drought or flood year. The century-long monthly rainfall data collected for four sub-divisions of the north-east Indian region spanning across 9 states (Arunachal Pradesh, Assam, Meghalaya, Nagaland, Manipur, Mizoram, Tripura, Sikkim, and Sub-Himalayan West Bengal) is utilized to compute the annual rainfall, average, standard deviation, and the normalized index. The results for each sub-division have been plotted to identify the normal, drought, or flood years. The results reveal that there is a significant inter-annual variation of rainfall over all the sub-divisions, leading to frequent drought and flood years. This study recommends the application of the normalized index over north-east Indian region due to its ease of computation and uniformity.

A NOAA tide gauge in Baltimore Inner Harbor has monitored sea level changes since 1902 for 116 years. This gauge seats on the over semi-consolidated Cretaceous strata of Arundel clay (Kac) underlain by Patuxent sand (Kxs) facies and the Pre-Cambrian undifferentiated crystalline rock. The Patuxent sand layer is the most important confined aquifer in the Baltimore history. The shallow Arundel clay and the deep Pre-Cambrian crystalline rock can be its upper and lower confining units, respectively. It was estimated that the groundwater pumpage increased gradually from practically nothing in about 1850 to about 23 thousand-m³/day in 1900 in the Baltimore area. After this the pumpage only increased slightly to 53 thousand-m³/day until about 1915. After 1935 the pumpage increased rapidly to 142 thousand-m³/day in 1941 then decreased. Primary compaction subsidence due to groundwater withdrawal is identified from the tide gauge records in this paper while secondary compaction subsidence due to creep under constant geohistorical overburden pressure is assumed to be zero since the maximum historical overburden pressure was released by uplift of the compressible aquifer system. A GPS receiver at University of Maryland at Baltimore County (UMBC) is 12 km far from the tide gauge located in the Baltimore Inner Harbor and seats on the late Precambrian Baltimore Gabbro Complex (bgb). Tectonic subsidence of 1.57±0.52 mm/year was measured at UMBC by using the GPS UMBC. So land subsidence in the Baltimore Inner Harbor consists of tectonic subsidence and primary compaction subsidence. We find an absolute sea level rise (SLR) of 1.11 mm/year by removing tectonic subsidence of 1.57 mm/year from a relative SLR of 2.68 mm/year during 1962 to 1980 with groundwater level stability in trend. Land subsidence impact on the sea level change in the inner harbor is empirically estimated to be 1.93 mm/year during 1903 to 1920, -3.15 during 1920 to 1926, 4.13 during 1926 to 1947, 1.74 during 1947 to 1957, -1.91 during 1957 to 1962, 1.57 during 1962 to 1980, and 2.17 during 1980 to 1992, respectively.

Extended hydrological prediction (EHP) is the prediction of hydrological variables for a period of time that exceeds the short-term forecasts. Extended forecasts help in supporting the optimal management of water resource and energy planning. Recent advances have pushed the limits of predictability of discharge and other hydrological variables from a few hours to several days or even months. Reliability of forecasts has increased in the recent years due to the integration of meteorological and hydrological modelling capabilities, improvements in data collection through satellite observations, and advancements in knowledge and algorithms for analysis and communication of uncertainties. The present paper reviews different aspects of extended hydrological prediction, including the models and different climate indices, emerging techniques of collecting inputs and displaying results, uncertainties, and warnings. A framework has also been developed for the understanding and development of EHP for Tehri Dam system. In the end, future directions for research and development are identified and presented.

More cities in the United States are identifying urban flooding as a frequent, destructive, and costly natural hazard affecting property, roadway, and other infrastructure while causing significant economic disruption, and negative consequences to human health and safety. In addition to rainfall during major hurricane and tropical storm events, coastal cities like New Orleans and Houston are vulnerable against high intensity short-duration rainfall events. Located below sea level and subjected to regional ground subsidence, New Orleans relies on their pumps and canals to handle one inch of rain the first hour, half-an-inch every hour thereafter. Aging and poorly maintained infrastructure systems can increase the amount of storm runoff to an already strained drainage system, creating pockets of flooding in ill-equipped and vulnerable neighborhoods. Using existing elevation certificates, BFE, regional subsidence rate, and inundation statistics from recent flooding events, this paper evaluates effects of subsidence on property elevation and long-term repetitive loss potential of the structures. An estimated yearly ground subsidence rate of 9 mm/year increased flooding potential from 30% to 42% for the properties evaluated.

This research work aimed to present sustainability practices directly linked to actions related to water resources during an event in Brasilia, capital of Brazil. A case study of the annual event called “Na Praia,” which had five previous editions, has been carried out. This event obtained a Zero Waste certification issued by the Zero Waste Brazil Institute once it reached up to 95% of waste recycling in the last three years. The event can contribute to the preservation of the water quality of Lake Paranoá, which is a water supply source in Brasília. To this end, the UN's 17 sustainable development goals (SDGs) are used as a guiding instrument. Seventeen goals are employed to achieve the general sustainability plan of the event and six goals are directly or indirectly linked to water resources: clean water and sanitation (water savings and reuse); affordable and clean energy (solar energy for the store and mobile phone charging); responsible consumption and production (use of electric hand dryers and water soluble toilet paper); climate action (carbon emission reduction, planting trees); and life below water (reduction of plastic use at the event, 100% oil recycling of used kitchen, taken from the garbage of the bottom of the Lake Paranoá). Since 2017, 350,000 m² of native trees have been restored in the Descoberto River Basin.

Carbon capturing and sequestration are of great interest to reduce the carbon dioxide CO₂ emissions from the atmosphere. To achieve this, forests, grasslands, and vegetation areas, in general, should be planted and conserved. However, for cultivating a landscape, water resources become an issue for some regions specifically in the arid areas where they have water scarcity and use desalination of seawater for life amenities. Even with using relatively clean energy source (natural gas), desalination is responsible for 12 kg of CO₂ eq m-3 with high consumption of electricity and energy resources. Alternating this with treated wastewater with good purity can help reuse of treated sewage effluent TSE, abate the consumption of resources, and mitigate the emissions of CO₂. This scenario was applied in the middle east region, particularly in Qatar where the 2022 World Cup event will be held. An intensive project was established near Doha north TSE with the potential of reducing the massive amount of CO₂ by natural sequestration through planting trees and grasslands. Efficiently, TSE exclusively was used to cover the need of the whole landscape. In this study, the focus was on studying the potential mitigation of carbon by measuring the operational carbon footprint from facilitating and planting the landscape, the carbon captured by the whole landscape (trees, grassland, soil, etc.), and the net carbon storage and neutralization. Initial results showed that the usage of TSE was able to reduce the CO₂ by approximately 12 times compared to desalinated water. With further investigation, the value of carbon sequestration through the landscape can provide positive net carbon storage helping in neutralizing carbon emissions with sustainable and natural facilities.

El Niño southern oscillation (ENSO) events throughout the world are known to influence regional (or local) hydroclimatic variability and changes in essential climatic variables (i.e., temperature, precipitation, and others). Variations in temperature extremes influenced by ENSO may lead to spatial and temporal variability of energy consumption and better management strategies by energy utilities. The focus of this study is to assess the possible influences of El Niño southern oscillation (ENSO) events on regional temperature characteristics and extremes along with residential energy consumption in South Florida. The region of interest comprising three counties namely Miami-Dade, Broward, and Palm Beach. Evaluation of ENSO events on temperature is carried out using long-term monthly mean, minimum, and maximum temperature data from 1961–2018 from serval sites located in these counties. Joint variation of monthly electricity consumption obtained from a local power utility and temperature data available from the year 2001 to 2018 are used in the study. Temporal windows that coincide with three phases of ENSO (i.e., warm, cool, and neutral) are used to evaluate changes in temperature and energy consumptions. Nonparametric hypothesis tests are used to confirm statistically significant changes in temperature and energy in different phases of ENSO. This study is expected to provide insights into the possible spatial and temporal influences of ENSO events on temperature and residential electricity consumption for South Florida. Preliminary results suggest that spatially non-uniform variations in temperature influenced by El Niño and La Niña events affect the residential energy consumption in South Florida. Insights gained from this study can help local power utilities to plan and manage energy production and distribution for future ENSO events.

Natural gas is often perceived as a commodity fuel with limited variability, largely due to extensive standardization of pipeline-quality natural gas. Once natural gas is processed and entered into the transmission and distribution system, it is nearly pure methane with limited tolerance for impurities. Upstream of the transmission and distribution system, however, natural gas characteristics vary substantially. For example, production basins have highly variable carbon dioxide (CO₂) and other non-methane (CH₄) content. Extraction and processing practices vary as well. One of the most significant environmental characteristics of natural gas is its greenhouse gas (GHG) intensity, which has increasingly been highlighted as shale-based production continues and as attention to the requirements for a fully decarbonized energy system grows. It is well established that methane leakage from natural gas systems is higher than long understood, largely due to variation in leakage during the production stage. Such leakage varies by basin. Similarly, the CO₂ content of raw gas varies by basin. This work uses recent research findings from some of the U.S.’ primary natural gas production basins, in addition to information about the location of natural gas infrastructure, to establish methods to determine first-order estimates of the GHG of natural gas being used around the United States. Although natural gas is a commodity product, the environmental footprint of a given unit of natural gas can vary substantially based on its origin and infrastructural needs. Using existing data, we outline methods to quantify where natural gas from each basin is ultimately being consumed.

Nano-engineered materials have unveiled never before possibilities in many avenues including water treatment, structural engineering, electronics engineering, materials science, and medicine. Since 2005, there has been a steady increase in the number of nanoparticle containing products available in the market. While these nanoparticles offer remarkable potential in many avenues, the likelihood of them finding a way to the environment is inevitable. As production volumes keep increasing it is critical to note that the effects of ingestion of these nanoparticles by living systems is poorly understood. In this paper, we present some of the most predominantly used nano-engineered materials identified through literature review and examine their possible pathways into the environment. Also, we summarize the results from the various studies conducted to understand the effects of these common nanoparticles on bacteria. Most studies have focused on studying the effect of one or two types of nanomaterials on bacteria. Moreover, there is no clear consensus on findings owing to the different characteristics of the nano-materials studied, the diverse experimental methods adopted and the choice of bacterium used. This article will bring together a body of knowledge and highlight differences in the various existing findings on evaluating the effects of nanomaterials on bacterial growth.

Much research has focused on promoting sustainable living practices. However, this body of research is largely dispersed and fragmented across fields such as basic psychology, public health, environmental science, civil engineering, and construction management. This review seeks to examine this body of research and summarize key themes to provide answers such as: what interventions have been proposed to enhance sustainable living, what interventions have been empirically tested, what problems can the interventions tackle, and what are the benefits of adopting these sustainable living interventions? The objective of the article is to provide a critical review of the literature to identify areas where progress has been made and areas where progress is yet to be made. The findings demonstrate that most of the sustainable living interventions have been designed to target key areas which include energy consumption, water conservation, transportation issues and challenges, and waste management. A variety of intervention elements such as the provision of relevant knowledge, feedback on performance, and rewards for portraying desirable behaviors were found in the literature. The article can serve as a resource to practitioners, researchers, policymakers, teachers, and students—who seek to understand the fragmented literature and wish to be informed about the state of the science. It is also expected that the article will empower readers with practical interventions that they themselves can adopt to promote sustainable living and public wellbeing in their communities.

Safety engineering construction for rural drinking water in China started in 2005. After more than 10 years of construction, approximately 500,000 central water supply projects and countless plans are scattered everywhere. Ensuring the long-term operation of such projects is a major problem in the actual operations, in addition to concerns with the water source, technologies, management, staffing, and knowledge relating to water supply. Many management techniques are particularly ineffective in rural areas. After all, the necessary management model is not extant. National policies are reviewed through in-depth analysis and research on the management of water supply utilities in rural areas. The main project management modes in our country include public ownership company management, stock company management, contract management, institution management, and entrusted management. The various types of management models in China are summarized to develop a sustainable model that can help improve the management system of water supply projects in rural areas.