Hydrological and Environmental Impact of Wastewater Treatment and Reuse on Zarqa River Basin in Jordan

environments

Article Hydrological and Environmental Impact of Wastewater Treatment and Reuse on Zarqa River Basin in Jordan

Naser Almanaseer 1,* , Muna Hindiyeh 2 and Raha Al-Assaf 3 1 Department of Civil Engineering, Faculty of Engineering, Al-Balqa Applied University, Al-Salt 19117, Jordan 2 Department of Water and Environmental Engineering, Faculty of Engineering, German Jordanian University, Amman 11180, Jordan; [email protected] 3 Technical University of Vienna, 1040 Vienna, Austria; [email protected] * Correspondence: [email protected]

Received: 16 October 2019; Accepted: 9 February 2020; Published: 12 February 2020

Abstract: Treated wastewater is an important component of the water resource in Jordan. As Samra wastewater treatment plant—the largest treatment plant in Jordan—discharges ~110 MCM per year of secondary treated municipal wastewater to Zarqa River, and eventually to Jordan Valley. This research aims at assessing the impact of treated wastewater reuse on the hydrology and environment in the most vulnerable areas within Amman-Zarqa Basin, specifically from As Samra treatment plant to Jerash Bridge. Historical data is collected, field survey is performed, and chemical and biological analyses are performed at eleven selected locations along the study area. Afterwards, all collected data is managed using suitable tools to address the impact. The findings of this research demonstrate high improvement in biological and microbial parameters along the flow path, yet the salinity is increased downstream. It is found that this increase is due to brackish water intrusion, apparently from sandstone aquifer. Analysis of BOD and COD carried out as part of this research showed effective system recovery with COD reduction from 130 mg/L at the effluent to less than 50 mg/l in the downstream. Moreover, microbial activities are reduced, mainly due to self-purification in the river.

Keywords: hydrology; groundwater; surface water; irrigation; environment; wastewater; Zarqa River; As-Samra treatment plant; farmers; microbial

1. Introduction

1.1. Background Water scarcity is dominant in arid and semi-arid regions, resulting in high competition among diﬀerent sectors such as domestic and agriculture causing a gap between supply and demand. To manage this gap, it is important to understand the root causes of this problem. Classical causes in Jordan include population growth, demographic variables, and infrastructure-related problems. Further, the impact of climate variability and change aﬀects the condition and creates unbalance between surface water and groundwater in spatial and temporal scales [1] Further, population growth, industrialization, irrigation, and other activities accelerated the exhaustion of available resources [2]. To overcome these challenges, adaptive integrated water resources management plan is indispensable. In fact, it has the ability to utilize future forecasts of surface and groundwater resources considering reliable precipitation models [3]. In Jordan, one important nonconventional water resource is treated wastewater. As Jordan is highly dependent on groundwater resources, it is critical that Jordan plan to protect groundwater resources from both reduction and contamination especially in strategic aquifer systems. Values of total coliform and E. Coli observed near Ramtha treatment plant in Northern Jordan

Environments 2020, 7, 14; doi:10.3390/environments7020014 www.mdpi.com/journal/environments Environments 2020, 7, 14 2 of 14 indicate groundwater contamination. To be specific, total coliform content reach 1600 MPN/100 mL, and E. Coli content of 500 MPN/100 mL in groundwater systems in the mentioned area [4]. On the other hand, Jordan is significantly depending on its agricultural sector for ensuring food security at local level, and to export vegetables and other products to Europe and to the Gulf Region. Sustainable agriculture requires soil conservation and demands the application of suitable water for irrigation to avoid salinity [5]. Consequently, Jordan needed to secure adequate water supply for agriculture, specifically in Jordan Valley. For all these consideration, Jordan effectively invested in wastewater treatment and reuse in Azraq Basin (AZB), where treated wastewater is mixed with fresh water of the Zarqa River. The mixed water is collected in King Talal Dam (KTD) and used with other resources for irrigation needed in Jordan Valley [6]. We discuss the impact of treated municipal wastewater reuse in fragile ecosystems, to be specific, in Messolonghion Lagoon and Acheloos Estuary. It describes the planning of the treated wastewater reuse in this ecologically sensitive area, on the basis of the geomorphologic and geotechnical characteristics, climatic factors, and crop irrigation water requirements grown in the area. We found that the municipal wastewater reuse for crop irrigation grown in the protected area appears to be an environmentally acceptable solution for alleviating the natural water shortage. Also, the authors of [7] discuss the optimum transfer factor of heavy metals from soil to plant. The optimum heavy metal transfer factors were found during multiple linear regression analysis, under the effect of treated municipal wastewater. Based on the parameters used in the multiple regression equation, the pollution load index is found to be statistically significant related to transfer factor. Another aspect of the river environment is the interaction between surface water and groundwater, and the role of climate variability and change in controlling this interaction. Jordan is highly dependent on groundwater with limited availability of surface water. This research investigates and evaluates the impact of treated wastewater reuse on the environment and on public health in the most vulnerable area within Amman-Zarqa Basin, specifically from As Samra treatment plant to Jerash Bridge. Historical data is collected, field survey is performed, chemical and biological analyses are performed at eleven selected locations, and all data is managed using suitable tools to address the impact. The findings of this research demonstrate high improvement in biological and microbial parameters along the flow path yet the salinity is increased downstream. It is found that this increase is due to brackish water intrusion, apparently from the sandstone aquifer. Analysis of BOD and COD carried out as part of this study showed effective system recovery with COD reduction from 130 mg/L at the effluent to less than 50 mg/L in the downstream. Moreover, microbial activities are reduced, mainly due to self-purification in the river. On the other hand, interviews with 27 farmers indicate a considerable reuse of treated wastewater leading to high economic return due to proximity to water and high nutrient load maximizing productivity. Crop analysis is considered to evaluate the impact on public health through contaminants uptake by plants. This analysis showed that the trace elements in the examined crops tend to accumulate in the green matrix through phyto accumulation, and therefore protects fruits. Overall, the outcomes of this research indicate safety of treated wastewater reuse in irrigation practices except for greens. The only concern, however, is the microbial contamination which can be reduced through environmental management and considering survival time of microbes in the environment. Based on the data collected over the past decade, adoption of wastewater treatment and reuse in AZB clearly helped bridge the gap between supply and demand. Accordingly, decision-makers at the Jordanian Ministry of Water and Irrigation of Jordan (MWI) are considering non-conventional water resources as a feasible option in their water management and development strategies [8,9], shedding some light on the potential environmental implications and the interactions of pharmaceuticals and personal care products PPCPs on the soil for a more effective monitoring of these emerging contaminants in the plants and soil continuum. The controlled wastewater treatment and reuse is evident in the Jordanian legal documents such as National Water Strategy 2016–2015 [10], Decentralized Waste Water Strategy 2016 [10], and the Environments 2020, 7, 14 3 of 14

Wastewater Management Policy [11]. Also, Water Authority Law No. 18/1988 amendments 16/1998, 62/2001, state that “wastewater shall not be disposed of; instead, it shall be a part of the water budget”. However, in particular areas, the application of treated wastewater may disturb the environment depending on the efficiency of treatment process, and on the water supply system. As Samra wastewater treatment plant—the largest treatment plant in Jordan—discharges ~110 MCM per year of secondary treated municipal wastewater to Zarqa River, and eventually to Jordan Valley. A few years after its construction, the efficiency of As Samra started to decrease due different reasons, primarily overloading, and therefore gradual environmental deterioration. In 2008, As Samra was reconstructed and upgraded to enlarge its capacity and enhance effluent quality. Overall, this intervention results in evident improved ecosystem services that needed quantification, which is the focus of this research. In 1985, As Samra wastewater treatment plant was constructed to serve approximately two million people in Amman and Zarqa Governorates [12]. With time, the efficiency of the treatment unit is degraded due to overloads causing clear environmental problems along the river course downstream to Jordan Valley. In 2008, As Samra wastewater treatment plant was reconstructed and upgraded from stabilization ponds type of treatment to mechanical type, discharging ~100 MCM per year of secondary treated wastewater with an average salinity of 900 ppm. The quality of the effluents is significantly improved. This improvement in the quality of treated wastewater displays an opportunity toward environmental restoration of the area along Zarqa River. This restoration may enhance the ecosystems along the river and in KTD area, benefitting the farmers, and therefore the agriculture section. Further, this restoration will certainly improve the sanitation and health aspects in the area. For example, after the upgrade of As Samra wastewater treatment plant, the river is carrying more than 100 MCM of continuous flow with improved water quality. As a result, groundwater level within the area is replenished. However, ~20% of the irrigation water within the study area is shifted from groundwater to treated wastewater due to the availability and quality of treated wastewater. This shift, however, may result in enhanced environmental conditions in terms of soil, groundwater, and the ecosystem in general.

1.2. Problem Statement Due to the shortage of fresh water in semiarid and arid regions, treated municipal wastewater is increasingly used for crop irrigation. In Jordan, where almost all arable land is intensively farmed and water resources are being overutilized, the risk of exposures and adverse health effects from agricultural activities are high. Moreover, the risks are magnified because much of Jordanian farming takes place in close proximity to population centers. This enhances the direct and indirect effects of agriculture on the surrounding municipalities and environmental system including soil, surface and groundwater. In Jordan, ~85% of the treated wastewater (TWW) is used for crop irrigation; this comprises ~35% of the total irrigation water [13,14].

1.3. Research Objectives This research utilizes tools to examine the use of treated wastewater along Zarqa River in conjunction with other available water resources by taking into consideration their quantity and quality, in addition to the agronomic, environmental, and economic components. The main objective of this effort is to assess the impact of wastewater treatment and reuse on the environment, including surface water, groundwater, biodiversity, as well as on the public health over selected locations within the study area. To achieve these two main objectives, a series of methodologies and techniques were adopted to ensure adequate data collection and management, illustrative field and laboratory work, proficient collection and analysis of chemical and biological parameters, inclusive field survey and questionnaire targeting farming practices in the study area, and finally SWOT analysis to conclude solid present and future implications of the wastewater reuse on the environment and public health in the study area. Environments 2020, 7, 14 4 of 14

Environments 2020, 7, 14 4 of 15 1.4. Study Area 1.4. Study Area 1.4.1. Location 1.4.1. Location The overall basin (AZB) comprises an area of ~4025 km2, where 89% is located in Jordan and 11% The overall basin (AZB) comprises an area of ~4025 km2, where 89% is located in Jordan and 11% inside the Syrian territory. The climate within the basin is ranging from wet to dry. Land use is very inside the Syrian territory. The climate within the basin is ranging from wet to dry. Land use is very diverse as well [15]. To be precise, the focus of this research covers the area from As Samra to KTD diverse as well [15]. To be precise, the focus of this research covers the area from As Samra to KTD (Figure(Figure1). 1).

FigureFigure 1. 1. LocationLocation of of the the study study area. area.

1.4.2.1.4.2. Hydrogeology Hydrogeology BasedBased on on the the hydraulic hydraulic parameters, parameters, the Hummarthe Hummar Limestone Limestone formation formation represent represent the water-bearingthe water‐ layerbearing composing layer composing the upper the aquifer upper system aquifer withsystem an with average an average thickness thickness of 150 of m 150 with m anwith average an saturatedaverage thickness saturated of thickness 120 m as of shown 120m as in shown the hydrogeological in the hydrogeological cross section cross alongsection the along river the (Figure river 2). The(Figure productive 2). The Hummar productive aquifer Hummar is a vital aquifer aquifer is a vital in the aquifer river basinin the used river forbasin agricultural used for agricultural and domestic supplyand domestic for the last supply 3 years. for the In last the 3 current years. In time the thecurrent domestic time the supply domestic was supply abandoned was abandoned due to increased due salinityto increased and the salinity treated and waste the treated water waste ﬂowing water in flowing the river in whichthe river is which in direct is in interaction direct interaction with the groundwaterwith the groundwater system. The system. Hummar The AquiferHummar is Aquifer separated is separated from the deepfrom sandstonethe deep sandstone aquifer by aquifer the clay andby silt the layer clay ofand Na’ur silt layer marlstone of Na’ur with marlstone an average with thicknessan average of thickness 100 m. of 100 m. TheThe Deep Deep Sand Sand Stone Stone Aquifer Aquifer System System knownknown locally as as Kurnub Kurnub sandstone sandstone aquifer aquifer is not is not widely widely investedinvested for for water water supply supply due due to to high high salinitysalinity that exceeds exceeds 2500 2500 mg/L. mg/L. It Itis is believed believed that that no nodirect direct interactioninteraction is takingis taking place place among among the the upper upper and and the the deep deep aquifer aquifer as as the the deep deep aquifer aquifer is is not not under under high high artesian pressure. Downward leakage is also neglected due to very law hydraulic conductivity artesian pressure. Downward leakage is also neglected due to very law hydraulic conductivity of the of the aquitard unit [16]. aquitard unit [16].

Environments 2020, 7, 14 5 of 14 Environments 2020, 7, 14 5 of 15

Environments 2020, 7, 14 5 of 15

Figure 2. Figure 2. Cross section of of Zarqa Zarqa River. River.

Figure 2. Cross section of Zarqa River. TheThe sources sources of of groundwater groundwater recharge recharge in in Amman-ZarqaAmman‐Zarqa Basin Basin can can be be classified classified into into two two classes: classes:  NaturalThe sources recharge: of groundwater this type can recharge be categorized in Amman as direct‐Zarqa recharge Basin can (direct be classified infiltration into oftwo rainfall) classes: and • Natural recharge: this type can be categorized as direct recharge (direct infiltration of rainfall) indirect recharge (which takes place when water percolates to the water table in localized areas  Naturaland indirect recharge: recharge this (whichtype can takes be categorizedplace when aswater direct percolates recharge to (direct the water infiltration table in of localized rainfall) through fracture or in areas where the soil cover is very thin or not existing). andareas indirect through recharge fracture (whichor in areas takes where place the when soil watercover ispercolates very thin to or the not water existing). table in localized  ArtificialArtificial recharge: recharge: this this type type takes takes place place directly directly at at the the point point of of activities. activities. It includesIt includes resources resources such • areas through fracture or in areas where the soil cover is very thin or not existing).  asArtificialsuch irrigation as irrigation recharge: return flow,return this physicaltype flow, takes physical losses, place anddirectlylosses, leakage and at the leakage from point water fromof activities. supply water networkssupply It includes networks and resources effl uentand of wastesucheffluent water as irrigationof treatmentwaste water return [16 treatment ].flow, However physical [16]. [8 However], losses, groundwater and [8], leakagegroundwater recharge from is waterrecharge dominant supply is indominant networks the upper in and the Zarqa Rivereffluentupper (AS Zarqa of Samra waste River plant water (AS area). Samra treatment This plant approach [16]. area). However This was approach based [8], groundwater on was water based budget onrecharge water and changebudgetis dominant and of soil change in storage the whichupperof soil is Zarqastorage controlled River which (AS by landis Samra controlled use plant and area).by soil land water This use approach holding and soil was capacity. water based holding Theon water resulted capacity. budget natural The and resulted change recharge toofnatural the soil groundwater storage recharge which to the found is groundwater controlled to be in theby found rangeland to use be of in 3and tothe 12soil range mm water /ofyear, 3 holdingto which12 mm/year, capacity. is largely which The controlled isresulted largely by controlled by rainfall distribution and topographic slope. The spatial distribution of natural rainfallnatural distribution recharge to andthe groundwater topographic found slope. to The be in spatial the range distribution of 3 to 12 of mm/year, natural which recharge is largely is shown recharge is shown in Figure 3. incontrolled Figure3. by rainfall distribution and topographic slope. The spatial distribution of natural recharge is shown in Figure 3.

Figure 3. Recharge in the study area. FigureFigure 3. 3. Recharge in in the the study study area. area. The hydrology of the study area is controlled by topographic relief, geology, and land use. A numberTheThe hydrology of hydrology side intermittent of of the the studystudy streams area discharges is is controlled controlled to Zarqa by by topographic River. topographic In general, relief, relief, the geology, drainage geology, and system land and withinuse. land A use. A numbernumberthe study of of canside side be intermittent intermittent described streamsas streams complex. discharges discharges The catchment to Zarqa to Zarqa River. area River.of In Zarqageneral, In River general, the drainage(Amman the drainage system Zarqa withinBasin) system withinthe study the study can be can described be described as complex. as complex. The catchment The catchment area of Zarqa area of River Zarqa (Amman River (AmmanZarqa Basin) Zarqa

Environments 2020, 7, 14 6 of 14

Environments 2020, 7, 14 6 of 15 Basin) spreads from the slopes of Jabel Druz to the Jordan River. Zarqa River has the second largest areaspreads of drainage from the basin slopes and of mean Jabel annual Druz to discharge the Jordan in River. Jordan. Zarqa The River River has comprises the second two largest main area divisions: of Wadidrainage Dhuleil, basin which and mean drains annual the eastern discharge part in of Jordan. the catchment The River area, comprises and Sail two Zarqa, main divisions: which drains Wadi the westernDhuleil, part. which Both drains meet the at eastern Sukhna part to formof the thecatchment Zarqa River.area, and As Sail expected, Zarqa, which the eastern drains branchthe western drains onlypart. flood Both flows meet as at a Sukhna result of to precipitation, form the Zarqa where River. the As western expected, branch the eastern drains branch flood drains and base only flows flood [17 ]. flowsAZB as receives a result of an precipitation, average annual where precipitation the western branch of ~237 drains mm. flood The and eastern base flows catchment, [17]. which comprisesAZB around receives half an of average the total annual catchment precipitation area, receives of ~237 an averagemm. The amount eastern of catchment, precipitation which of 182 mmcomprises/year. The around western half catchment, of the total comprisingcatchment area, the receives highlands an average and the amount Jordan of Valley precipitation area, receives of 182 an averagemm/year. precipitation The western rate catchment, of 397 mm comprising/year. Precipitation the highlands over and the the highlands Jordan Valley can occur area, inreceives the form an of average precipitation rate of 397 mm/year. Precipitation over the highlands can occur in the form of snow; in the eastern part of the Basin, it is generally rainfall [17]. snow; in the eastern part of the Basin, it is generally rainfall [17]. Figure4 shows the long term record of the Zarqa River base flow which indicates the Figure 4 shows the long term record of the Zarqa River base flow which indicates the surface– surface–ground water interaction. The discharge into the Zarqa River is resulted from a complicated ground water interaction. The discharge into the Zarqa River is resulted from a complicated drainage drainagesystem system governed governed by topographic by topographic relief. relief. According According to this to thisrecord, record, overpumping overpumping and and climatic climatic variabilityvariability reduced reduced the riverthe river base base flow inflow the in 1970s, the 1970s, which waswhich recovered was recovered later on duelater to on the due construction to the of Asconstruction Samra plant of As and Samra recovering plant and surface recovering and groundwater surface and groundwater resources in resources the area. in the area.

FigureFigure 4. 4.Long-term Long‐term record of of base base flow ﬂow in in Zarqa Zarqa River. River.

1.4.3.1.4.3. Wastewater Wastewater In AZB,In AZB, there there are are a number a number of wastewater of wastewater treatment treatment plants plants which which discharge discharge their their effluents effluents directly or indirectlydirectly or toindirectly Zarqa River. to Zarqa The River. total eTheffluent total of effluent treated of wastewater treated wastewater in AZB exceeds in AZB 120exceeds MCM 120/year. AsMCM/year. Samra plant As effl Samrauent aloneplant effluent is more alone than 110is more MCM than/year. 110 MCM/year. As Samra is As the Samra only is treatment the only treatment plant within theplant study within area. the As study Samra area. treatment As Samra plant treatment was plant constructed was constructed in 1985 nearin 1985 Kherbit near Kherbit As Samra As Samra Village. In theVillage. period In the of 1985period to of 2008, 1985 the to 2008, notably the notably negative negative impacts impacts of As Samraof As Samra effluent effluent were were reflected reflected on the wateron the quality water of quality the river, of the and river, therefore and therefore on the on ecosystem. the ecosystem. In 2008, In 2008, As SamraAs Samra treatment treatment plant plant was upgradedwas upgraded to mechanical to mechanical and chemical and chemical treatment treatment system therefore system therefore the effluent the quality effluent was quality significantly was improved.significantly The improved. secondary The treated secondary wastewater treated is wastewater discharged is along discharged Zarqa along River Zarqa to be mixedRiver to in be KTD withmixed rainfall in KTD water, with and rainfall released water, to and through released the to river through to a conversionthe river to a dam conversion near Jordan dam near Valley. Jordan From Valley. From this point, the mixed water is channeled toward Jordan Valley for a second mixing in this point, the mixed water is channeled toward Jordan Valley for a second mixing in King Abdullah King Abdullah Canal. The final product is distributed for irrigation along central and southern parts Canal. The final product is distributed for irrigation along central and southern parts of Jordan Valley. of Jordan Valley. 2. Materials and Methods 2. Materials and Methods A cluster of interconnect methods and techniques is utilized to achieve the two main objectives of A cluster of interconnect methods and techniques is utilized to achieve the two main objectives this study. These methods and techniques include data collection from files and from the field, desktop of this study. These methods and techniques include data collection from files and from the field, datadesktop management data management using spreadsheet using spreadsheet and ArcMap, and ArcMap, laboratory laboratory analysis analysis of chemical of chemical and biological and parameters,biological laboratoryparameters, analysis laboratory of selected analysis crops, of selected and field crops, survey. and Following field survey. is a description Following ofis thesea methodsdescription and techniquesof these methods and techniques

2.1. Data Collection and Management

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2.1. Data Collection and Management All existing data related to the study were collected from diﬀerent sources. Collected data included data sets on groundwater, surface water, climate, landuse, and soil from the open ﬁles of Jordanian Ministry of Water and Irrigation. In addition to that, data were extracted from previous research and reports by researchers and master student. All collected and extracted data were organized in a geospatial data base with geographical locations. Data validation indicated some gaps and missing in the groundwater, climate, and soil data collected from the Jordanian Ministry of Water and Irrigation.

2.2. Field Survey Field survey is carried out to validate the collected existing data and to fill the required data related to water resources, wastewater reuse, conjunctive use, land use, soil, agriculture productivity and practices, potential environmental, and public health issues. To accomplish this, a survey sheet is designed to include list of relevant questions with the focus on two areas: crop type and farmer’s practices. The questions are addressed by direct contact with 27 farmers in the study area, and one workshop was organized to have all target groups in one room and extract the needed data. The survey sheet for two categories: crop type and farmer practices with results expressed in percentage are presented in Table1. Based on the outcomes of this basic field survey, a list of locations is defined for water and plants sampling.

Table 1. Field survey of farmers practices in the study area.

Category 1: Crop Type Category 2: Farmers Practices Number of Agricultural Rounds % Irrigation Type % 2 Rounds 41 Mixed 9 1 Rounds 59 Flooded 12 Source of Water Sprinklers 18 Mixed 22 Drip 61 GW 30 Fertilizers Use TWW 48 Mixed 15 Water Mixing Ratio GW:TWW Organic 18 2 to 1 33 Chemical 67 1 to 1 67 Pesticides Use Is Water Suﬃcient According to help of experts 15 Yes 44 According to farmer knowledge 85 No 56 Calculating Crop Water Demand Is Water Quality Suitable According to help of experts 6 Yes 15 According to farmer knowledge 94 High salinity 22 Water Mixing Ratios to Avoid Salinity High turbidity 63 According to help of experts 9 Is Soil Quality Suitable According to farmer knowledge 91 Sandy soil 7 Select Crop Type Poor soil 11 According to water and soil quality 6 High salinity 26 According to help of experts 9 Yes 56 According to market demand 21 Crop Type According to farmer knowledge 64 Grapes 7 Expert Help and Support Maize 7 Private expert 12 Citrus 8 Agrochemical companies 12 Alfalfa 26 Governmental expert 15 Olive 26 Farmers community 15 Vegetables 30 Self-dependent 46 Crop Economic Return Very good 11 Fair 22 Low 26 Good 41 Knowledge on Reuse Impacts Yes 22 No 78 Environments 2020, 7, 14 8 of 14

2.3. Water Sampling and Analysis Water samples were collected at eleven defined points within the study area along Zarqa River. These eleven points are defined based on exiting data and field survey. The selected points are geographically distributed over a length of approximately 22 km, extended from As Samra treatment plant to Jerash Bridge. The selected points represent As Samra plant effluent, mixing point with Ain Gazal water, springs area, high agricultural return flow spots, and zones with surface water–ground water interaction. The samples were collected by researchers and a master’s student. During this research, three samplings are collected from each point at interval of approximately two months covering late summer and early winter. The samples are analyzed for a number of chemical and biological parameters according to Standard Methods for Examination of Water and Wastewater, 2007. The determined parameters are as follows.

Total Dissolved Solids (TDS) were measured according to (2540 C. Total Dissolved Solids dried at • 180 ◦C). Chemical Oxygen Demands (COD) were measured according to (5220 D. closed reflux colorimetric • method). BOD and DO were measured according to (4500-O G. Membrane Electrode Method). • BOD was measured according to (5210 B. 5 days BOD test). • Total Coliform and E. coli were measured according to (9223 B. Enzyme Substrate Test). • The pH and electrical conductivity (EC) were measured by using pH and EC meters. • Determination of Soluble Sodium and Potassium were determined by using flame photometer. • Determination of Soluble Calcium and Magnesium: Calcium titration with EDTA where the • Magnesium was determined by (using atomic Absorption). Determination of Bicarbonate: The Bicarbonate was determined by titration by H SO . • 2 4 Determination of Chloride was done by titration by Silver nitrate (AgNO ). • 3 Heavy metals (Cd, Zn, Cu, Fe, and Mn) were determined by Atomic absorption spectrophotometer. • Olsen-P was determined by Spectrophotometer. • The findings are documented and tabulated using spreadsheet. Dominant quality parameters are used to determine a list of parameters to be tested in the plants

2.4. Plant Sampling and Analysis Samples from eleven crops were collected in the study area. The plant samples are collected near the eleven water sampling points to relate water quality to plant contaminant uptake level. Samples were analyzed for plant root, leaf, and fruits. Analysis covered microbial contamination (E. Coli) and trace elements. The used methods were drying, digesting then analysis. The samples were prepared as 800 mg plant sample then heated with 10 mL nitric acid (70%), and then the samples were heated another time with 8 mL Perchloric acid (70%). After cooling, 30 mL of distilled water was added and the resulted 100 mL sample was analyzed using Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Analyses were done in collaboration with UFZ labs in Germany as part of SMART MOVE and PECTAKE projects funded by BMBF.

3. Results

3.1. Field Survey Field survey targets a number of irrigated farms within the study area. The outcomes of the conducted ﬁeld survey for both crop type and farmer’s practices are discussed below. Environments 2020, 7, 14 9 of 14

3.1.1. Crop Investigations The crop investigations are conducted based on a number of questions. The outcomes of this investigation are summarized in Table1. The survey indicates that 41% of the surveyed farms apply two agricultural rounds of vegetables and cereals, whereas 59% applies single round of trees such as olives, grapes and citrus. Also, the survey shows that 48% of the interviewed farmers considered treated wastewater as the only source for irrigation, whereas 30% use groundwater. On the other hand, some mixing practices were recorded when the water sources are limited, which represents 22% of the farmers. This, however, can be justified by the high cost of groundwater exploration, high salinity of groundwater, and restricted laws. For water sufficiency, more than 55% of the farmers stated that water supply is way below the needed amounts. Remarkably, the rest own private groundwater wells that secure the farms. This is due to the growing food market in Jordan, especially in the last two years, as a result of the political situation in the region; most of the farmers intensify agricultural activities in the river basin. Concerning the water suitability for irrigation from the farmer’s point of view, 22% of farmers highlighted salinity problems in groundwater, and 15% of farmers reported high turbidity in the river which can affect plant yield and irrigation systems. Based on the field survey, 26% of the interviewed farmers reported that they are facing high soil salinity and more water is being used in the washout treatment. Also, poor soil and high sand content were observed in less than 20%. Within the study area, a variety of crops are present covering a wide spectrum of vegetables, fruit trees, and cereals. It was found that 30% of the water is reused for vegetables irrigation including but not limited to tomato, cucumber, green pepper, onion, greens, eggplant, and okra. Most of the previous crops are ready for human use without cocking indicating a potential health risk. On the other hand, olive, citrus, and grapes trees farming is being practiced in ~20% of the total sample and considered as the old practice for local community in the area. Due to knowledge exchange and development in agricultural practices in the last few years, the economic return for local farmers is enhanced significantly. This is recorded during the field investigation when more than 50% of the total sample declared a good to very good economic return. The rest, which is less than 50%, are below expectations and with a low economic return because of the traditional practices, low education, and soil–water quality. On the other hand, ~22% of the famers indicated existing knowledge on the environmental and health impact through different awareness programs took place in the last few years, while the higher percentage with 78% of the farmers show no previous knowledge on the impacts of such reuse.

3.1.2. Farmer Practices The farmer practices are conducted based on a number of questions and the outcomes are summarized in Table1. Irrigation is one of the major concerns in agricultural water management due to the complexity of the system in the country and the dependency on different water sources with different qualities. Within the sample, drip irrigation is being practiced over 62% due to the efficiency of this irrigation type and the affordable cost of drip irrigation lines and connections. Drip irrigation is mainly used for vegetables and some trees, whereas sprinklers are the used technology for alfalfa and field crops with 17% of the sample. The old technology of flood irrigation is still in practice in some small farms (12%) if the farm is very close to the river system and here no pumping is needed. Agrochemicals are widely used in the area to enhance productivity and reduce risk of diseases and fungal infections. Chemical fertilizers found to be widely used in 67% of the sample due to low cost and easy use guaranteed solution. Pesticides use is one of the riskiest practices done by farmers, which may affect farmer health, crop quality, and ecosystem components. Lack of help and support to farmers toward the safe use of such chemicals was noticed as 15% of the sample received support and help by experts to handle such chemicals. When investigating the process guiding the calculation of water requirements for the crops along the Zarqa River system; the expert guidance and follow up, Environments 2020, 7, 14 10 of 14 which is the most important part in this matter, was almost totally missing, as only 6% of farmers stated that they are having expert management, whereas 94% said that they have been doing it according to their personal knowledge, which is not suitable in most cases. The water extracted from the aquifer has the potential to be mixed with the water coming from Zarqa River which may lead to deteriorate and increase the salinity of the irrigation water and therefore, affect the crops, soil and groundwater in the area. To have a better understanding of the procedures applied by the farmers along the river system, an investigation was varied out to determine how much is the experts contribution in this process; amazingly the results were disappointing as only 9% of the farmers consult experts in this matter and 91% of them have been doing it according to their previous knowledge and experience which is not enough in most cases where each crop requires certain values of mixing which leads to the point of the experts guidance in the field of crop selection. As known during the year and with the seasons change; different cropping patterns can be applied over each area along the river system. Also, it was found that only 9% of farmers consult experts in order to plant a well guided crop with a previous perspective of the results. Six percent of farmers choose their crops to be planted according to the water and soil quality as they do not want to take any risks. Twenty-one percent determine this process after studying the market and the demand where they can plant demanded crops and get the best benefits, whereas 64% of farmers choose their crops according to their previous knowledge and experience. The investigation states that 15% of the guidance is coming from the farmers local community, 12% of the total guidance comes from private experts, and agrochemical companies contribute in ~12%, leaving only 15% of the management and guidance of this important agricultural environment for governmental experts and the self-dependent management dominates with a percent of 46% leaving us with a potential environmental catastrophe that may occur after some time without guided and well-studied management processes.

3.2. Water Quality Generally, wastewater quality is deﬁned by many parameters and constituents. One of the most important parameters is macro-organic matter, which includes biochemical oxygen demand (BOD) and chemical oxygen demand (COD). BOD is the amount of oxygen that is removed from water during organic matter consumption by bacteria, whereas COD is the amount of oxygen removed from water due to organic matter consumption by chemical matters. Other parameters include micro pollutants, trace elements, microorganisms and pathogeneses, and total dissolved solids (TDS) generated from inorganic soluble salts. Three rounds of water samples were collected at eleven deﬁned points within the study area.

4. Discussion

4.1. Physical Parameters Based on ﬁeld measurements, it was clear that water in the river, which is actually a mix of fresh and treated wastewater, has pH values ranging from 7.5 to nearly 9, whereas the turbidity ranges from ~21 to ~126 Nephlometric Torpidity Unit (NTU). However, pH tends to increase toward downstream

4.2. Major Anions and Cations Comparing chemical treated wastewater quality to the Jordanian standards (Water—Reclaimed domestic Wastewater Standard 893/2006) it is concluded that most of the tested samples comply with the reuse standards. Starting by the effluent of Samra plant at S1, we can conclude that the COD is the only parameter that exceeds the standards. Moving downstream some parameters increase due to different factors. The elevated values of parameters can be justified by the illegal practices and Environments 2020, 7, 14 11 of 15

4.2. Major Anions and Cations EnvironmentsComparing2020, 7, 14 chemical treated wastewater quality to the Jordanian standards (Water—Reclaimed11 of 14 domestic Wastewater Standard 893/2006) it is concluded that most of the tested samples comply with the reuse standards. Starting by the effluent of Samra plant at S1, we can conclude that the COD is excessivethe only irrigation. parameter Such that practicesexceeds the are standards. clear with Moving the elevated downstream levels of some Na and parameters Cl while increase NO3 is relateddue to fertilizersto different or factors. contamination The elevated by other values sources. of parameters can be justified by the illegal practices and excessiveTwo types irrigation. of correlation Such practices coefficients are areclear used with to the examine elevated the levels interrelationships of Na and Cl or while the dependency NO3 is betweenrelated the to fertilizers variables. or These contamination two types by are other as follows. sources. Two types of correlation coefficients are used to examine the interrelationships or the Pearson product-moment correlation coefficient, also known as r, R, or Pearson’s r, a measure of • dependency between the variables. These two types are as follows. the strength and direction of the linear relationship between two variables that is defined as the  Pearson product‐moment correlation coefficient, also known as r, R, or Pearsonʹs r, a measure of (sample) covariance of the variables divided by the product of their (sample) standard deviations. the strength and direction of the linear relationship between two variables that is defined as the Rank correlation, the study of relationships between rankings of different variables or different • (sample) covariance of the variables divided by the product of their (sample) standard deviations. rankings of the same variable Spearman’s rank correlation coefficient, a measure of how well the  Rank correlation, the study of relationships between rankings of different variables or different relationshiprankings of between the same two variable variables Spearman can beʹs rank described correlation by a coefficient, monotonic a function. measure of how well the relationship between two variables can be described by a monotonic function. In this research, we adopted Pearson correlation. For example, the chemical constituents of major cationsIn and this anions research, are we analyzed. adopted The Pearson correlations correlation. show For strong example, dependency the chemical between constituents Na and of major Cl with R2 cationsabout 0.88. and anions The relation are analyzed. between The both correlations Na and Clshow with strong TDS dependency is also examined. between The Na analysis and Cl with shows strongR2 about dependency 0.88. The between relation Nabetween and Cl, both with Na TDS. and Cl This with indicates TDS is thatalso Naexamined. and Cl The playing analysis strong shows role in controllingstrong dependency TDS. Therefore, between the Na salinity and Cl, is dominantlywith TDS. This driven indicates by Na that and Na Cl. and Figure Cl playing5 demonstrates strong role the in controlling TDS. Therefore, the salinity is dominantly driven by Na and Cl. Figure 5 demonstrates correlation between the chemical variables. the correlation between the chemical variables.

700 2000 R² = 0.87 600 1750 R² = 0.88 R² = 0.88

500 (mg/l) 1500

TDS (mg/l)

Cl 400 1250

Na : TDS Cl : TDS 300 1000 100 200 300 400 500 0 200 400 600 800 Na (mg/l) Na, Cl (mg/l)

FigureFigure 5. 5.Correlation Correlation between between NaNa and Cl (left) and and Na Na and and Cl Cl with with TDS TDS (right). (right). 4.3. Biochemical Parameters 4.3. Biochemical Parameters ThreeThree samples samples from from each each sampling sampling pointpoint are collected and and analyzed analyzed for for a anumber number of ofbiological biological parametersparameters including including BOD BOD and and COD COD correlation correlation analysis among among the the different different variables variables is carried is carried out out to commentto comment on on the the dependency dependency among among the the selected selected variable. variable. Considering Considering historic historic data data from from MWI MWI files, thefiles, analyses the analyses done during done thisduring study this clearly study showclearly that show values that ofvalues both of BOD both and BOD COD and become COD become healthier in 2016healthier compared in 2016 to compared prior 2008. to prior This significant2008. This significant improvement improvement in water quality in water is quality due to is the due upgrade to the of Asupgrade Samra implemented of As Samra implemented in 2008. in 2008. OnOn the the other other hand, hand, the the analysis analysis shows shows thatthat there is is strong strong dependency dependency between between Total Total Coliform Coliform andandE. ColiE. Coli.R.2 Ris2 is computed computed at at 0.92 0.92 (Figure (Figure6 6),), which which isis a strong indication indication of of the the interdependency interdependency of of thesethese two two variables. variables. Consequently, Consequently, strong strong dependencydependency between between BOD BOD5 5andand COD COD is isclear. clear. As As BOD BOD5 5 andand COD COD are are commonly commonly dependent, dependent, and and thethe same applied for for Total Total Coliform Coliform and and E. E.Coli Coli, the, the strong strong correlationcorrelation among among them them indicates indicates reliable reliable data data andand accurate analysis. analysis. BOD5 and COD analysis validate the fact that the river environment can be categorized into three distinct zones; decomposition, septic, and recovery. Further, these three zones represent different environments considering dissolved oxygen, pollution loads, and types of aquatic species. COD and BOD5 are generally directly related to dissolve oxygen in any aquatic system. The analysis conducted in this study for COD and BOD is in agreement with this concept. In addition, the analysis shown significant recovery toward the downstream area (Figures6 and7) and in agreement with the three Environments 2020, 7, 14 12 of 15 Environments 2020, 7, 14 12 of 15

BOD5 and COD analysis validate the fact that the river environment can be categorized into three BOD5 and COD analysis validate the fact that the river environment can be categorized into three distinct zones; decomposition, septic, and recovery. Further, these three zones represent different distinct zones; decomposition, septic, and recovery. Further, these three zones represent different environments considering dissolved oxygen, pollution loads, and types of aquatic species. COD and environments considering dissolved oxygen, pollution loads, and types of aquatic species. COD and BOD5 are generally directly related to dissolve oxygen in any aquatic system. The analysis conducted EnvironmentsBOD5 are2020 generally, 7, 14 directly related to dissolve oxygen in any aquatic system. The analysis conducted12 of 14 in this study for COD and BOD is in agreement with this concept. In addition, the analysis shown in this study for COD and BOD is in agreement with this concept. In addition, the analysis shown significant recovery toward the downstream area (Figures 6 and 7) and in agreement with the three significant recovery toward the downstream area (Figures 6 and 7) and in agreement with the three zones mentioned above. However, field observations suggest that the anomaly in BOD5 and COD at zoneszones mentioned mentioned above. above. However, However, ﬁeld field observations observations suggest that that the the anomaly anomaly in in BOD BOD5 and5 and COD COD at at sampling point number 9 is due to illegal disposal of wastes such as manure, plant remaining, and samplingsampling point point number number 9 9 is is due due to to illegal illegal disposaldisposal of wastes wastes such such as as manure, manure, plant plant remaining, remaining, and and other sorts of wastes. otherother sorts sorts of of wastes. wastes.

Figure 6. Correlation between total coliform with E‐Coli (left) and BOD5 with COD (right). FigureFigure 6. 6.Correlation Correlation between between total total coliformcoliform with E E-Coli‐Coli (left) (left) and and BOD5 BOD5 with with COD COD (right). (right).

FigureFigure 7. 7.BOD BOD5 5and and COD COD valuesvalues measured at at 11 11 sampling sampling points points in in the the study study area. area. Figure 7. BOD5 and COD values measured at 11 sampling points in the study area. 4.4.4.4. Groundwater Groundwater Impact Impact 4.4. Groundwater Impact BasedBased on on the the above above results, results, we concluded concluded that that the the quality quality of treated of treated water water is improved is improved due to due Based on the above results, we concluded that the quality of treated water is improved due to to the enhanced performance performance and and efficiency eﬃciency of of As As Samra Samra Treatment Treatment Plant. Plant. Also, Also, due due to tonatural natural the enhanced performance and efficiency of As Samra Treatment Plant. Also, due to natural puriﬁcationpurification along along the the river: river: the the analyses analyses ofof BODBOD5,, COD, COD, and and DO DO clearly clearly demonstrated demonstrated that. that. Further, Further, purification along the river: the analyses of BOD5, COD, and DO clearly demonstrated that. Further, thisthis environmental environmental recovery recovery directly directly boosted boosted agriculture agriculture in terms in terms of production of production and quality. and quality. However, this environmental recovery directly boosted agriculture in terms of production and quality. it wasHowever, clear that it was Electrical clear that Conductivity Electrical Conductivity (EC) is increased (EC) is in increased the downstream in the downstream area. To further area. assessTo However, it was clear that Electrical Conductivity (EC) is increased in the downstream area. To thefurther impact assess of treated the impact wastewater of treated on agriculture,wastewater on we agriculture, considered we EC considered as one of EC the as indicators, one of the and further assess the impact of treated wastewater on agriculture, we considered EC as one of the indicators, and therefore we examined EC values along the study area. The analysis shows that EC thereforeindicators, we examinedand therefore EC we values examined along theEC values study area.along The the study analysis area. shows The analysis that EC valuesshows that measured EC values measured at the 11 sampling points are in the range of approximately 1900–3100 μS/cm. at thevalues 11 samplingmeasured pointsat the 11 are sampling in the range points of are approximately in the range 1900–3100of approximatelyµS/cm. 1900–3100 Sampling μS/cm. points 1 Sampling points 1 through 8 shows EC ranging from 1938 to 2122 with an average of 1987 μS/cm. On throughSampling 8 shows points EC 1 through ranging 8 fromshows 1938 EC ranging to 2122 from with 1938 an average to 2122 with of 1987 an averageµS/cm. of On 1987 the μS/cm. other On hand, samples collected at points 9–11 showed EC ranging from 2468 to 3060 with an average of 2825 µS/cm. The collected data suggests that elevated EC toward the downstream area is not related to the surface water or wastewater treatment process: it is, however, due to upward leakage of brackish groundwater from the sandstone (Kurnub) aquifer (Figure8). Environments 2020, 7, 14 13 of 15

the other hand, samples collected at points 9–11 showed EC ranging from 2468 to 3060 with an average of 2825 μS/cm. The collected data suggests that elevated EC toward the downstream area is Environmentsnot related2020 to, 7 ,the 14 surface water or wastewater treatment process: it is, however, due to upward13 of 14 leakage of brackish groundwater from the sandstone (Kurnub) aquifer (Figure 8).

FigureFigure 8. 8.Upward Upward leakage leakage of of brackish brackish groundwater from from the the sandstone sandstone (Kurnub) (Kurnub) aquifer. aquifer.

5. Conclusions5. Conclusions It isIt clearis clear that that the the application application of of TWW TWW influences influences Zarqa Zarqa River River system.system. This influence, influence, however, however, is varyingis varying in space in space and and time, time, and and can can impact impact the the ecosystem ecosystem positively positively and and/or/or negatively negatively depending depending on theon local the conditions.local conditions. ForFor groundwater groundwater in in the the study study area, area, thethe infiltrationinfiltration of of TWW TWW that that is is steadily steadily mixed mixed with with surface surface freshfresh water water increases increases the quantitative the quantitative resilience resilience of groundwater of groundwater system, apparentlysystem, apparently due to groundwater due to rechargegroundwater at the river recharge bed andat the river river banks. bed and On river the other banks. hand, On the the other same hand, groundwater the same rechargegroundwater lead to unfavorablerecharge lead environmental to unfavorable impacts environmental due to the presenceimpacts due of some to the chemical presence and of biologicalsome chemical constituents, and suchbiological as heavy constituents, metals, pathogens, such as heavy pharmaceuticals, metals, pathogens, and otherpharmaceuticals, undesirable and constituents. other undesirable Further, theconstituents. study concluded Further, a gradualthe study increase concluded in surface a gradual water increase salinity in towardsurface downstreamwater salinity duetoward to the downstream due to the interaction between surface water and saline groundwater. interaction between surface water and saline groundwater. For ecosystem, it is clear that TWW flow enhanced regional ecosystem services through For ecosystem, it is clear that TWW flow enhanced regional ecosystem services through formation formation of additional springs and expansion of vegetation cover. Further, the TWW containing of additional springs and expansion of vegetation cover. Further, the TWW containing nutrients added nutrients added into the river improves the environmental conditions of the river results in a intohealthier the river ecosystem improves and the amenity. environmental This enhancement conditions however, of the river is resulted results in in improved a healthier agricultural ecosystem andsector amenity. and further This enhancement society resilience. however, is resulted in improved agricultural sector and further society resilience.The data collected demonstrated a strong correlation between BOD5 and COD indicating reliableThe data measurements. collected demonstrated Based on these a strongmeasurements correlation and betweenanalysis, the BOD5 study and fully COD demonstrated indicating reliable that measurements.the microbiological Based content on these of TWW measurements is decreases and toward analysis, downstream; the study this fully improvement demonstrated is due that to the microbiologicalaeration in the content river course of TWW and is decreasesresulted in toward improved downstream; water quality. this improvementMoreover, samples is due from to aeration the in thecrops river are courseanalyzed and for resulted fecal coliform in improved E. Coli, and water for heavy quality. metals Moreover, as well. samples The analysis from showed the crops that are analyzedthe E. Coli for in fecal irrigation coliform waterE. Coli is much, and higher for heavy than metalsthe standards. as well. On The the analysis other hand, showed E. Coli that was the foundE. Coli in irrigationto be in the water green is muchcrops higher(Rocca, than cauliflower, the standards. lettuce, On and the green other onion). hand, E.It was Coli wasconcluded found that to be this in the greenvariation crops (Rocca,is due to cauliflower, proximity to lettuce, soil and and high green surface onion). area It of was the concluded plant. Corn that and this potato variation reveal isno due to proximitypresence of to E. soil Coli and in the high edible surface parts. area For of trace the elements plant. Corn in irrigation and potato water, reveal the no study presence concluded of E. that Coli in thethere edible is no parts. trend For in tracethe results elements that can in irrigation be connected water, to the the distribution study concluded of the sampling that there points. is no trend in theAuthor results Contributions: that can be connected Conceptualization, to the distributionN.A.; M.H.; and of R.A.A. the sampling Methodology, points. N.A. and M.H.; software, N.A. and R.A.‐A.; validation, N.A. and M.H.; formal analysis, N.A. and R.A.‐A.; investigation, N.A.; M.H.; and R.A.‐ Author Contributions: Conceptualization, N.A.; M.H.; and R.A.-A. Methodology, N.A. and M.H.; software, N.A. and R.A.-A.; validation, N.A. and M.H.; formal analysis, N.A. and R.A.-A.; investigation, N.A.; M.H.; and R.A.-A.; resources, N.A. and R.A.-A.; data curation, N.A. and R.A.-A.; writing—original draft preparation, N.A. and M.H.; writing—review and editing, N.A.; visualization, R.A.-A.; supervision, N.A. and M.H. All authors have read and agreed to the published version of the manuscript. Funding: This research received no external funding. Environments 2020, 7, 14 14 of 14

Acknowledgments: The authors acknowledge the contributions and assistance of Al-Balqa Applied University for providing their laboratories and facilities. The authors thank the University of Jordan for making their laboratory accessible to this research. Special appreciation goes to the farmers within the study area for their great help and interest in this research. Finally, plant samples were analyzed using Inductively Coupled Plasma Mass Spectrometry (ICP- MS). The authors acknowledge that these analyses were done in collaboration with UFZ labs in Germany as part of SMART MOVE and PECTAKE projects funded by BMBF. Conﬂicts of Interest: The authors declare no conﬂicts of interest.

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