LTCP is located at the coastal area of Lavrion, Attica, within the wider area of Athens. The case study combines all typical Mediterranean water problems (i.e. seawater intrusion, water scarcity, karst aquifers, irrigation etc.) and MAR application is envisaged to combat all those. The site offers a typical hydrogeological setting for a Mediterranean coastal aquifer system (containing both alluvial and karstified aquifer layers), supporting both irrigation as well as water supply demands of the area. The entire aquifer system suffers from: (i) water shortage resulting from both anthropogenic activities (overexploitation) and natural conditions (decreasing precipitation trends due to climate change), as well as (ii) contamination due to the intrusion of seawater. The pilot site involves the employment of infiltration basins, which will be using waters of impaired quality as a recharge source, hence acting as a Soil-Aquifer-Treatment (SAT) system. This system is complemented by new technological developments, which will be providing continuous monitoring of the quantitative and qualitative characteristics of infiltrating groundwater through all hydrologic zones (surface, unsaturated and saturated zone). This will be achieved through the adaptation and installation of an integrated system of prototype sensors installed on-site offering a continuous monitoring and evaluation of the performance of the SAT system.
An integrated approach of the performance evaluation of any operating SAT system should aim at simultaneous monitoring of all hydrologic zones, proving the sustainability of all involved water quality treatment processes within the unsaturated and saturated zone. The pilot site will also provide the development of a prototype system of Time Domain Reflectometry (TDR) sensors in order to achieve continuous quantitative monitoring of the unsaturated zone through the entire soil column down to significant depths below the SAT basin. This will be complemented by Frequency Domain Reflectometry methods offered by UFZ (Partner 13), providing a higher resolution of vertical soil moisture distribution on a multi-level non-stop basis. The combination of these techniques will offer continuous monitoring of infiltration rates and possible mechanical clogging effects. The qualitative monitoring of the unsaturated zone will be achieved by installation of appropriate pore-water samplers within a multi-level basis, ensuring repeatability of sampling of infiltrating water of impaired quality. Lastly, prototype water multiparameter sensors will be developed for the qualitative and quantitative assessment of the Lavrion multi-aquifer system. This will continuously monitor the performance of (i) the alluvial aquifer and its potential for additional water treatment as well as (ii) the effects of the SAT system for counter-measuring seawater intrusion in the area of Lavrion.
The site is located close to an agricultural area in Schiavon municipality in the Province of Vicenza. The topic tackled is rural water management, specifically the problem of water scarcity and conflicts with other water users in the irrigation season.
The study will assess the potential of MAR to enhance the ecological status of groundwater in the North East Alpine District. The NE Alpine system constitutes an aquifer with abundant freshwater of very good quality in which meteorological processes (mainly rain and snow precipitations) allow the storage and the release of waters in the environment through glaciers, lakes, springs, rivers, groundwater bodies, and soils. The NE Alpine system is nevertheless extremely vulnerable in relation to climate change and the current water resource management. In the last 30-40 years, the water table has slowly but progressively declined, numerous wetlands have been desiccated (straining the resurgence ecosystem and its biodiversity) and the aquifers have been depressurized as result of over-exploitation; these negative effects are likely to worsen in the next decades as the frequency and intensity of droughts and water scarcity intensify. Still, groundwater can remain the primary water source for the Italian Northern Adriatic basins if managed in a sustainable manner and, even better, if recharge is established.
The DEMO site uses a Forested Infiltration Area (FIA) for Aquifer Storage and Recovery (ASR). The FIA uses furrow irrigation for ensuring infiltration into the aquifer; an ecological crop cultivated on the overland area maximizes the infiltration rate and provides environmental services. A system of furrows is fed by drainage channels connected to the irrigation ditch of the local irrigation network. The system operates continuously during the non-irrigation period during winter season ensuring that ecological flows of rivers are maintained, and on an intermittent basis during the irrigation period during summer season. The DEMO intends to show the impact of Infiltration Forested Areas on:
Aquifer Storage and Recovery. This activity foresees implementation of monitoring and mathematical modelling using state-of-the art methodologies, sensors and models in order to accurately monitor infiltration rates. Monitoring of the springs nearby the DEMO site will contribute to quantify the impact of the MAR in the restoration of the resurgence system. Additional soil investigation and the infiltration monitoring will help to develop a calibrated hydrogeological mathematical model of the site that simulates infiltration in the unsaturated zone and recharge of the aquifer. The benefits of cultivation in the MAR area to prevent clogging will be demonstrated as well as the potential of MAR to abate nitrates. With the support of the mathematical model it will be possible to extrapolate data to the NE Alpine Upper Aquifer and assess the impact of MAR on the restoration of the aquifer and resurgence system.
Ecological monitoring. The design and implementation of landscape restoration in the areas set for aquifer recharge will be another issue examined at the DEMO site. This important activity is in line with the general principles of the WFD 2000/60/EC, and it falls under the Management Plan governed by the same Directive. A specific project for environmental restoration and landscaping, starting with the study of the most suitable and native tree species, will allow the establishment of stable plant communities. The restoration will have, among others, the purpose of attracting animal species typical of humid environments, in particular birds. The landscape will act as a meeting point between 'objective' environments (i.e., habitat, ecosystems) and 'subjective' environments, those perceived by the different actors involved.
Ecological Services. An analysis of the opportunities for the environment and the economy provided by FIA will be undertaken. For instance the cultivation of fast-growing trees can turn out an economic benefit for land owners whilst providing an environmental service (e.g. trees for paper production and biomass energy generation).
Cost-benefit analysis of MAR versus conventional solutions for water supply. The potential water banking assumes different management scenarios, incorporating climate change issues and measures to mitigate the impacts of water scarcity and drought on the aquifer, with the purpose to exploit groundwater in a sustainable way in compliance with the WFD 2000/60/CE. A cost-benefit analysis will quantify the effects of MAR with respect to alternative solutions in accordance with the guidelines to the WFD Common Implementation Strategy (CIS) and to the River Basin Management Plans.
Along the Serchio River, Lucca Province in Tuscany, a series of well fields is set for an overall amount of about 1 m3/s pumped groundwater providing drinking water for about 300,000 people of the coastal Tuscany (mainly to the town of Pisa and Livorno). The needed water for pumping is made available by enhancing river bank infiltration into a high yield (10-2 m2/s transmissivity) sand and gravel aquifer by rising the river head. During dry climate extremes (i.e. 2002/2003 or 2011/2012), Serchio River flow may be as low as 3 m3/s. This poses a threat to the river minimum environmental flow (MEF) as the volume abstracted is barely 30% of the river flow (which is already 33% of the adopted MEF). The problem can be limited through aquifer recharge measures. However, unintended/unmanaged aquifer recharge may arise concerns both from the quantitative and the qualitative point of view (potential contamination of river water).
The Serchio well field site currently does not have a monitoring program and can therefore be used to demonstrate the feasibility of aquifer recharge by a technical and economical point of view and the benefits of managing induced river bank filtration versus unmanaged one. Beyond the development of new sensors or monitoring systems, the innovation at the site will consist in merging existing technologies to create a control platform where the operation at the well fields are continuously and automatically monitored and managed. Data will be acquired continuously by means of a set of sensors. Synergies may arise by using sensors developed within the context of the project by other partners. Data will be continuously acquired and the connected modelling tools will consist in spatially distributed and physically based coupled surface water/groundwater flow and solute transport models developed on a GIS platform and along with optimization models whose aim will be: (i) estimating induced infiltration rates, (ii) estimating travel times, (iii) optimize groundwater exploitation in complex well field schemes, (iv) performing forecasting simulations on prevention of pollution events, (v) performing time estimates for remedial actions, and (vi) performing simulations on the effectiveness of remedial actions to be set in place.
A Decision Support System (DSS) combining and integrating measurements results and modelling will be developed and equipped with an alert system to inform water managers about the system performance and reaching limits of infiltration rates against MEF or water quality indices.
All the developed system will be benchmarked against potential market exploitation.
The "Campina de Faro" aquifer system is classified as poor groundwater status in the recently finished watershed management plan of Algarve region. It also integrates the "Faro" protected area (vulnerable zone). This is an area of strong agricultural practices where rehabilitation through artificial recharge is welcome, aiming at the minimization of diffuse pollution effects caused by traditional agricultural practices.
Demonstration is carried out in two infiltration basins located in the Rio Seco river bed at the Campina de Faro DEMO site. According to studies developed during the GABARDINE EU project, in average 5.6 hm3 of water are annually available for artificial recharge, not uniformly distributed along the year but available only during about 67 days per year, in winter time. The demonstration activities include infiltration of surface flow water to monitor the long-term infiltration capacity of the basins and potential clogging effects, and the assessment of the groundwater quality improvement in the area. The final aim would be to transform the Rio Seco stream along its path over the Campina de Faro aquifer system into an infiltration stream by constructing infiltration basins all along the stream. The infiltrating water would contribute to dilute and to increase the gradient towards the sea shore of the contaminated water.
The DEMO site is equipped with two infiltration basins (each 20 m x 5 m, 5 m deep), filled with clean gravel, and three monitoring wells for groundwater quality and piezometric levels measurement. The facility also has two concrete sections where two pneumatic gauges for river water levels control were installed, upstream and downstream of the infiltration basins. Near the infiltration basins monitoring wells are located which will be used to monitor the results of the aquifer recharge process in terms of diminishing electrical conductivity and nitrate. The entire infiltration basin will be continuously monitored: (i) river discharge upstream and downstream of the infiltration basins, (ii) piezometric levels, electrical conductivity, and nitrate at the monitoring wells in order to monitor the performance of the infiltration basins.
Besides the infiltration basins, large diameter wells (locally called "nora") are available in most of the Algarve aquifers, including the Campina de Faro aquifer, and will be included in the demonstration activities. Their characteristics are exemplified by: area at the bottom of the "nora" with a diameter of 5 m = 19.625 m2; total well depth = 24 m; available storage volume at the "nora" = 373 m3. The monitoring equipment used includes multiparametric water sensors for continuous monitoring installed in the "nora" and in a nearby well for continuously recording the discharged water volume. Another experimental medium diameter well of 0.5 m diameter, located in Areal Gordo and called LNEC6, is also available for the demonstration.
The effectiveness of the artificial recharge process will also be monitored using geophysical surveys (electrical resistivity profiles), conducted by LNEC.
To enlarge the knowledge on the capability of MAR to improve the water quality in areas with agricultural diffuse pollution, other areas will also be demonstrated: Ribeiro Meirinho stream site, where infiltration/treatment basins will be used to reduce nitrate concentrations by recharging treated effluents of the WWTP of Sao Bartolomeu de Messines in the karstic Querenca-Silves aquifer; Cerro do Bardo site near a small dam, where infiltration wells will allow the recharge of surface water into the deeper layers of the karstic Querenca-Silves aquifer, thus contributing to increase the groundwater storage of the aquifer system that further downstream is pumped for public supply; finally, Melides lagoon, where infiltration/treatment basins will be used to clean highly nutrient-rich water produced in rice fields that otherwise is directly discharged into the lagoon, with correspondent disastrous environmental impact.
The challenge in this study area is given by the dual need to (i) increase the strategic groundwater reserves in the Llobregat aquifer in order to supply Barcelona's metropolitan area, and (ii) at the same time to improve the quality of the groundwater in the aquifer:
Quantitative issues - MAR to increase direct recharge that has been diminished due to the changes in soil uses (impermeabilization of a number of areas).
Qualitative issues - Studying whether an active layer located in the bottom of an infiltration pond may enhance the degradation of certain organic contaminants.
Artificial aquifer recharge is facilitated at this DEMO through surface infiltration ponds. The site includes a sedimentation and an infiltration pond. Water for recharge is diverted from the Llobregat River. Recovery is not done at the same site, but a number of extraction wells are located downgradient. Since the river and the aquifer are disconnected, no infiltrated water eventually reaches the river.
The area is heavily instrumented. Outside the area there are several piezometers (some of them multilevel) and a pumping well. Within the infiltration pond some instrumentation has been placed in order to analyze the infiltrating water; these include temperature sensors, suction caps and a lysimeter.
Recently an innovative MAR technology was implemented in the field: a vegetal compost-made reactive organic layer. During the first two years after the layer installation in the infiltration pond, an improvement in the elimination of some pollutants present in the recharge water was observed, leading to a positive impact on the quality of the recharged water. The impact of the organic layer at large times has not been assessed. The work proposed involves the development of biogeochemical models to account for the processes taking place within the soil and the aquifer in an integrated platform (i.e., decantation and infiltration of suspended solids, chemical precipitation and biological degradation processes). This involves additional site characterization, with a number of hydraulic and tracer tests to find and map heterogeneous patterns. Infiltration can be mapped also using some geophysical imaging that could be included in the modelling process.
Emphasis will be placed in the description of processes occurring right below the pond, such as denitrification and reduction of organic matter, boosted by the microbial activity at the non-saturated zone. The immediate effect would be the release of greenhouse effect gases from the pond. Since measurements of emissions are difficult at the site, a prototype of an aquifer will be prepared at the lab and tested for gas emissions.
Since the mid-20th century the expansion of irrigation from "Los Arenales" aquifer, located in Castilla y Leon, Spain, has led to a decline in groundwater level of more than 20 m. The Aeolian sand aquifer, with an area of 1500 km2 and thickness up to 55 m is also very vulnerable to drought. In order to mitigate this impact, the Spanish Ministry of Agriculture (MAPA) developed MAR facilities in three pilot zones. The project, building works, tracking and further monitoring was entrusted to Tragsa Group. These were accompanied by improvements in water management, based on the organization of communities of irrigation farmers, exchanges of arable land, change in crops, improved efficiency of irrigation, extension of the energy supply net, and reduction of energy consumption. Also there was recovery of environmental features such as degraded wetlands (La Iglesia and El Senor lagoons), springs that had dried, dilution of nitrates and of other pollution vectors, etc.
At the Santiuste basin site, river water was diverted for recharge by gravitational flow through 18 km of buried pipes to the recharge facilities; including infiltration ponds, artificial wetlands, canals and large diameter wells. Researchers also successfully tested buried filter pipes and drainage ditches. Once constructed and commissioned, the works were transferred to the communities of irrigators, who are responsible for the management and maintenance, under the advice of specialists of the Duero Hydrographic Confederation (CHD) and Tragsa. Due to variable river flows annual volumes recharged in the two main pilots ranged between 0.5 and 12.2 Mm3 (Santiuste basin) and between 0.5 and 5.5 Mm3 (Carracillo council) between 2002 and 2008. The river water was supplemented by 0.5 Mm3/yr of treated sewage effluent since 2005. MAR facilities currently operative at the demonstration site are:
Initially some farmers resisted the new organizational structures and this was resolved through negotiation and informing the respective communities on sustainable development, environmental awareness and hydrogeological processes including the applications of MAR. Subsequently there has been an unintended increase of about 15% in the irrigated area due to what has been called "contagious effect", of a decline in the price of water, and in the costs of pumping. Organizational change has motivated a substantial environmental improvement, providing a basis for resolving emerging issues. Incipient economic resurgence is observed in these rural areas that had previously been depressed. Of concern is the growing demand for irrigation water in areas that are not so feasible for MAR. It is also worth mentioning that there are plenty of industries and SMEs depending on the aquifer storage apart from the agro-industry.
The proposed activities in the large-scale demonstration sites managed by Tragsa are:
There are still many gaps to solve and research to be done to mobilize industry and SMEs in this area, especially related to vegetables packing and exportation. Most of the older networks for monitoring are being wasted due to economic crisis, and the materials broken could not have been replaced by now. There has not been any budget to improve the materials and data-collection stations already deployed. At the demonstration sites, apart from recovering the monitoring systems and inoperative sensors, it is expected to achieve new results and developments such as, for example, flow meters and specific pilots to test and validate building works designs, in order to achieve the biggest infiltration rate plus successful and long life operability.
In the last decade, desalination of sea water made it possible to facilitate a stable supply of potable water that is almost free of the stress related to the variability in the natural recharge of reservoirs. In Israel, three currently operating desalination plants plus two new desalination plants under construction will by 2014 reach the production capacity of 585x106 m3 of potable water/yr (1.6x106 m3/day), which will make the sea the main source for domestic water supply in the country (~75%). The desalination plants were built under build-operate-transfer (BOT) contracts with the private sector which is currently - in addition to less dry periods during the last time - leading to production of excess water. Water authorities aim at seasonal storage as well as aquifer storage recovery (ASR) of large volumes of these surpluses in the adjacent coastal aquifer via artificial recharge.
The MAR activity at this site aims both at seasonal storage and ASR of desalinated sea water. At first stage, infiltration of water with low salinity (chlorine treated) desalinated sea water from the Hadera facility through sandy infiltration basins will be monitored at the Menashe site. Different aspects will be tested along the MAR activity: (i) unsaturated zone and aquifer dynamics of the MAR process will be monitored and modelled, (ii) mixing and migration of the desalinated water body will be studied, and (iii) geochemical aspects of infiltration of the low salinity water will be examined (dissolution/precipitation processes related to hydraulic property changes). As the desalinated water is treated with chlorine, disinfection by-products that may develop due to the MAR operation will be investigated. At the second stage, MAR of desalinated sea water through injection wells will be tested.
To record the aspects listed above, monitoring and sampling equipment will be installed in the unsaturated and saturated zone beneath the infiltration basin. Field studies are accompanied by lab experiments that are aimed to mimic long-term operation (years) in a short-time period (weeks) under different operation conditions, and by process- and data-based numerical modelling studies for scenario analyses.
It is expected that this pilot operation will facilitate the know-how for establishing proper guidelines for aquifer storage as a tool to deal with temporal surpluses of desalinated water and demonstrate the viability of this approach. Direct industrial implication would be the definition of tailored post-treatment recommendations for desalination plants, most effective infiltration schemes, and proper monitoring strategies to assure long-term performance.
This pilot-site for the implementation of a seawater intrusion barrier is located in the Southern region of Malta. This location presents the typical hydrogeological characteristics of a coastal 'floating-lens' aquifer system, in direct lateral and vertical contact with seawater. The selection of this site was guided by two further considerations, namely: (i) the groundwater body in this area is considerably degraded, particularly in terms of salinity; and (ii) the site is located close to the main wastewater treatment plant of the island, and thus to a reliable source of treated sewage effluent.
The site is located on the coastal margin of a predominantly agricultural region, which has historically suffered from a shortage of water supply and grou