Entwurf Deliverable 1.1.1 Assessment of Hydrological Variability and Wastewater Infiltration Impacts (Mountain Area of Cluster W
Total Page：16
File Type：pdf, Size：1020Kb
Entwurf Deliverable 1.1.1 Assessment of hydrological variability and wastewater infiltration impacts (Mountain area of Cluster West) [Titel wie DoW, um Cluster West ergänzt, Vorschläge sind willkommen] Executive Summary [Folgt] 1 Introduction The study area of Deliverable 1.1.1. is located on the western side of the Lower Jordan Valley, focussing on the Wadis Qilt, Nueima and Auja as well as on the highland areas to the west and northwest of the Wadi catchments (groundwater catchment) and is also including areas of Mediterranean surface water and groundwater drainage). Water supply in the study region is heavily dependent on spring water supplies, making the water supply systems highly susceptible to fluctuations in climate as well as to anthropogenic impacts, especially regarding the infiltration of treated and untreated sewage. Microbiological contaminants like E. coli are rapidly transported in the karst flow systems of the region and hence raw water management and appropriate treatment is of high importance for the water suppliers of the region. Water supply is often organised on municipality level from local sources, but also a few regional suppliers are present. Groundwater quality is also compromised by long-term 1 effects of wastewater infiltration and agricultural activities. For example nitrate concentrations display a rising trend for a large number of groundwater resources. Furthermore, due to the structurally highly complex geological setting and the largely unknown karstification, the catchment areas of groundwater resources are not delineated and the flow systems are poorly understood. In order to enhance the understanding of the natural resources and to provide high resolution hydrological data for local raw water management, a comprehensive hydrological monitoring network was established and maintained. Remote data transmission was established for the most important stations. Comparative investigations were carried out in Wadi Shueib on the eastern side of the Jordan Valley. Therefore, an intensive exchange and collaboration between the research groups on both sides was conducted. According to the original Description of Work (DoW), Deliverable 1.1.1 was organised into six tasks (1.1.1.1–1.1.1.6). In practice, the different tasks were largely carried out in a cohesive way. Therefore, the content of this deliverable is re-structured in order to enhance readability and to avoid repetitions. In the individual chapters references to the original DoW structure are provided, where appropriate. This deliverable involves a large amount of cooperative fieldwork in the West Bank region. A major field campaign of six week’s duration was conducted in autumn 2015, involving in total five employees of Göttingen University (October–November 2015). It was intended to complete the installations before the start of the winter rainfall season 2015/2016. To achieve this task, already extensive preparations were necessary beforehand, i.e. planning for the installations (including a field survey in April/May 2015), selection and tests of the instruments, organisation of shipment to the project region etc.. Another larger campaign was conducted during February 2016 in order to calibrate the monitoring stations (e.g. by discharge measurements) and to conduct a large sampling campaign during the main winter precipitation events. Unfortunately, these two most important fieldwork campaigns were largely affected by a very unstable safety situation in the region (see e.g.: 2015–2016 wave of violence in Israeli- Palestinian conflict, https://en.wikipedia.org/wiki/2015%E2%80%932016_wave_of_ violence_in_Israeli-Palestinian_conflict; Wikipedia). This escalation of the conflict caused in total >250 fatalities and restricted movement in the project region which also caused considerable detours during travel and field work due to roadblocks, checkpoints etc. Here it is worth noting that without the profound local knowledge and experiences gather by parts of the German research counterpart since project phases SMART I & II (Mr. Fischer, Dr. Ries and Dr. Schmidt), barely any fieldwork would have been possible during such circumstances. Nevertheless, Task 1.1.1.3 – Characterisation of subsurface spring catchments and assessment of wastewater infiltration impacts by artificial tracer experiments, was particularly affected by the restrictions. In order to conduct this task, extensive surveys and preparations were carried out particularly in the office before the start of the main autumn 2015 field campaign, e.g. survey of possible injection sites via geological maps and cross sections and satellite images (e.g. via Google Earth). The following steps during the field campaign would have been to further investigate those sites in the field and to conduct infiltration experiments at the most promising ones (e.g. by Bedouin water tankers). Before the start of the tension, a few site visits could be carried out in this regard. However, they 2 were largely with an adverse result. Subsequently, according to the security situation, it was not possible to undertake any further site visits, let alone to conduct infiltration experiments etc.. Therefore, those planned experiments were largely delayed and had finally to be aborted due to insufficient manpower resources in the following. Nevertheless, a discussion of the generally planned tracer testing setup and potential injection sites is provided in chapter 4, in order to facilitate further investigations in the region. Despite the restrictions, a considerable field presence of the German research team could be maintained during the whole SMART-MOVE project (10 field campaigns in total). In this context, a large amount of technical training on-the-job was conducted; especially involving local water supplier personnel and local water resources authorities field crews. 2 Assessment of hydrological variability and relevant water quality parameters by high-resolution monitoring & concomitant technical training According to the original DoW this was organised into three interconnected tasks: Task 1.1.1.1 – Assessment of hydrological variability / Technical training of PWA personnel on high-resolution monitoring techniques (installation, maintenance, and data processing) Task 1.1.1.2 – Assessment of relevant water quality parameters (e.g. turbidity, nitrate, microbial contamination) for selected springs Task 1.1.1.4 – Assessment of meteorological parameters and surface runoff volumes Those works were usually carried out in combination, e.g. the maintenance and data retrieval visits were carried out for all parts of the networks in a spatially pooled way. 3 Figure 1: Overview map of the study area displaying the main springs and surface water (Wadi) catchments. [Karte wird noch ergänzt] 2.1 Spring monitoring installations and early warning system During the phases SMART I & II, spring monitoring was carried out at the large springs in the lower Jordan Valley (Auja, Duyuk, Sultan) and important springs for spring water supply on the flanks of the Valley (Samia). Those springs are characterised by rather extensive catchment areas. Therefore, especially anthropogenic impacts and corresponding spring signals are merged with natural recharge signals. Accordingly, for SMART-MOVE, focus was on small springs and therefore spring catchments in the highland recharge area displaying different degrees of urbanisation in order to discriminate natural recharge behaviour and anthropogenic impacts more clearly. For springs used for water supply, those kinds of investigations also provide the basis for an enhanced raw water management and treatment. 4 Figure 2: Examples of spring monitoring stations. Left: Assikka spring in Salfeet; Middle: Spring Areek Fouqa in Ein Areek; Right: Spring Ein Majur in Abu Qash. [Ausgewählte Ergebnisse] Early warning system [Kurzüberblick] 2.2 Meteorological and precipitation monitoring network Already at the start of the SMART-project, a network of automatic precipitation monitoring stations was installed in December 2007 in order to monitor the spatial distribution of precipitation. According to the main research area at that time, those installations focused on the headwater region of Wadi Auja and surroundings. During SMART II, were a special focus was on rainfall-runoff research, the monitoring network was considerably expanded with further meteorological and precipitation stations, now covering the whole catchment area of the western wadi cluster (see further Ries, 2017). With this network it was possible to study 5 rainfall-runoff processes and to quantify the hitherto unknown surface runoff amounts (Ries et al., 2017). During SMART-MOVE, most of those stations were continued, while a couple had to be abandoned due to high maintenance requirements, partly caused by vandalism at the respective sites. Since in SMART-MOVE, the focus was also on small spring groundwater catchments in the highland area and areas of Western (Mediterranean) drainage, the precipitation monitoring network had to be restructured in order to also cover those areas (see Figure 1). [Ausgewählte Ergebnisse] 2.3 Surface runoff monitoring The gauging stations established in SMART II were largely continued. A few stations with a poor accessibility, unstable stage-discharge relation and therefore a high maintenance demand were discontinued. The location of the stations is shown in Figure 1. Especially in Wadi Auja a clustered layout from small headwater catchments (4 km²) via medium scale catchments (14.5 km²) to Wadi