Novel approach to roof rainwater harvesting and aquifer recharge in an urban environment: Dry and wet infiltration wells comparison.

In urban environments there is a severe reduction of infiltration and groundwater recharge due to the existence of large impervious areas. During rain events, large volumes of water that could have recharged groundwater and surface water bodies are diverted into the municipal drainage system and lost from the freshwater storage. Moreover, extreme rain events impose high peak flows and large runoff volumes, which increase the risk of urban floods.

Mitigating risks and maximizing sustainability of treated wastewater reuse for irrigation.

Scarcity of freshwater for agriculture has led to increased utilization of treated wastewater (TWW), establishing it as a significant and reliable source of irrigation water. However, years of research indicate that if not managed adequately, TWW may deleteriously affect soil functioning and plant productivity, and pose a hazard to human and environmental health. This review leverages the experience of researchers, stakeholders, and policymakers from Israel, the United-States, and Europe to present a holistic, multidisciplinary perspective on maximizing the benefits from municipal TWW use for irrigation.

Maintaining intensive agriculture overlying aquifers using the threshold nitrate root-uptake phenomenon.

Reducing nitrate leaching from agricultural land to aquifers has been a high priority concern for more than a half century. This study presents theory and observations of a threshold concentration of nitrate in the root zone (Cmax), which the leachate concentration increases at higher rates with increasing root-zone nitrate concentration. The value of Cmax is derived both by direct results from container experiments with varying nitrogen (N) fertigation and as a calibration parameter in N-transport models beneath commercial agricultural plots.

Investigating geochemical aspects of managed aquifer recharge by column experiments with alternating desalinated water and groundwater.

Managed aquifer recharge (MAR) events are occasionally carried out with surplus desalinated seawater that has been post-treated with CaCO in infiltration ponds overlying the northern part of the Israeli Coastal Aquifer. This water's chemical characteristics differ from those of any other water recharged to the aquifer and of the natural groundwater. As the MAR events are short (hours to weeks), the sediment under the infiltration ponds will intermittently host desalinated and natural groundwater.

Impact of biosolids and wastewater effluent application to agricultural land on corticosterone content in lettuce plants.

We studied corticosterone occurrence in lettuce plants grown on three biosolids amended soils under irrigation with either tap water or secondary wastewater effluent. Corticosterone was examined as it has possible implications for human health. It is a major glucocorticoid, and as such has an effect on regulation of metabolism, immune functions and stress response.

Impact of biosolids and wastewater effluent application to agricultural land on steroidal hormone content in lettuce plants.

One of the major concerns for human health in the past decade is the potential dangers posed by increased concentrations of steroidal hormones in soils and water. These hormones are considered to be endocrine disrupting compounds (EDCs), which may harm human health when exposed to high concentrations, or in the case of long term exposure to lower concentrations. In a 3 year study, two steroids, estrone and testosterone, were measured in lettuce plants irrigated with wastewater effluents and freshwater and treated with several types of biosolids.

Nitrate fluxes to groundwater under citrus orchards in a Mediterranean climate: observations, calibrated models, simulations and agro-hydrological conclusions.

Nitrate contamination of groundwater under land used for intensive-agriculture is probably the most worrisome agro-hydrological sustainability problem worldwide. Vadose-zone samples from 0 to 9 m depth under citrus orchards overlying an unconfined aquifer were analyzed for variables controlling water flow and the fate and transport of nitrogen fertilizers. Steady-state estimates of water and NO3-N fluxes to groundwater were found to vary spatially in the ranges of 90-330 mm yr(-1) and 50-220 kg ha(-1) yr(-1), respectively.

Line-source multi-tracer test for assessing high groundwater velocity.

Segmented line-source multi-tracer injection is suggested as an effective method for assessing groundwater velocities and flow directions in subsurfaces characterized by high water flux. Modifying the common techniques of injecting a tracer into a well became necessary after point-source natural and forced gradient tracer tests ended with no reliable information on the local groundwater flow. The tracer's line-source increases the likelihood of success of the test and could provide additional information regarding the lateral heterogeneity of the aquifer.

Steady-state homogeneous approximations of vertical velocity from EC profiles.

Electrical conductivity (EC) logs were obtained by both open-borehole logging and passive multilevel sampling (MLS) in an observation borehole penetrating the Coastal Aquifer in Tel Aviv, Israel. Homogeneous vertical velocities for a 70-m thick subaquifer were approximated from each profile using a steady-state advection-diffusion model. The open-borehole log led to an overestimation of the steady-state upward advective flux of deep brines (vertical velocity of 0.

Correlating fracture trends and hydraulic head using semivariogram cloud analysis.

Fracture trends (defined as kilometer-scale linear features interpolated between field observations of fractures along their strikes) often have a dominant orientation. Finding a correlation between this orientation and hydraulic data could shed light on their hydraulic influence. A significant correlation between head residuals from first-order regional drift and the orientation of 2- to 4-km-long fracture trends was found in a study site in the Negev, Israel, using the semivariogram cloud analysis.