Assessment of rooftop rainwater harvesting in Ajloun, Jordan

In response to water scarcity in Ajloun governorate, Jordan, the effectiveness of implementing rooftop rainwater harvesting (RRWH) was investigated. In addition, a structured questionnaire was prepared and distributed to randomly selected residents to assess the status of the current RRWH practices in the governorate and the people's perceptions of this practice. It was found that between 0.39 million cubic meters (MCM) in a dry year (2017) and 0.96 MCM in a wet year (2018) can be harvested, which is equivalent to 7.6% and 16.8% of the domestic water supply for these years, respectively. The analysis of a total of 360 questionnaires revealed that only 14.2% of the households in Ajloun governorate own a RRWH system. However, the majority, 80.6%, of those who do not own a RRWH system showed interest in installing one. An overwhelming majority of the sample, 96.7%, believes that the government should provide incentives to subsidize the construction of RRWH systems, which is attributed to the high initial cost of these systems. The technical and social feasibilities of RRWH, in addition to the high cost of the alternatives, justifies providing incentives, such as cost sharing for the consumers in Ajloun to implement RRWH systems.

Inversión máxima para incrementar la disponibilidad de agua en comunidades de la zona limítrofe entre Quintana Roo y Campeche, México

La baja disponibilidad de agua potable de buena calidad puede ser complementada con agua proveniente de la lluvia, si esta última es recolectada en cantidad suficiente para cubrir la demanda, aprovechándose esta combinación para resolver el problema de abastecimiento, todo esto sujeto a restricciones de inversión. El presente trabajo tiene por objetivo presentar un análisis de los sistemas de captación de agua de lluvia existentes en la zona limítrofe entre los estados mexicanos de Quintana Roo y Campeche para estimar los montos de inversión máxima que justifiquen un proyecto de mejora en la disponibilidad de agua de lluvia. En esta investigación se identificó el nivel de aprovechamiento y los requerimientos de los sistemas de captación de agua pluvial en techos (SCAPT) y se determinó el monto de inversión máxima para solucionar esta situación problemática. Los resultados muestran que los SCAPT no se aprovechan debido a limitaciones o subutilización en la superficie de captación y/o capacidad de almacenamiento, por lo que se recurre al suministro de agua en pipas. Se concluye que se puede sustituir el acarreo en pipas por agua de lluvia con un adecuado dimensionamiento de la superficie y el volumen de captación, asegurando el consumo de agua mínimo recomendado, con una inversión menor de la que se requeriría para la implementación de un sistema de abastecimiento de agua convencional. Low availability of good quality drinking water can be complemented with rainwater, if the latter is collected in sufficient quantity to cover the demand, taking advantage of this combination to solve the supply problem, all of this subject to investment restrictions. The present work aims to present an analysis of the existing rainwater harvesting (RWH) systems in the border area between the Mexican states of Quintana Roo and Campeche to estimate the maximum investment amount that justifies a project to improve rainwater availability. In this research, the use level and the requirements of rooftop rainwater harvesting (RTRWH) systems were identified and the maximum investment amount needed to solve this problematic situation was determined. Results show that RTRWH systems are not used due to insufficient or underutilized catchment area and / or storage capacity, so water is supplied in tankers. It is concluded that transport in tankers can be replaced by RTRWH with an adequate dimensioning of surface and catchment volume, ensuring the minimum recommended water supply, with a lower investment than that required for the implementation of a conventional water supply system.

Rooftop rainwater harvesting potential for a domestic purpose using samsamwater, case of Jimma University Institute of Technology, Ethiopia

The key sources of water supply are rainwater, underground water and surface water. Rooftop rainwater harvesting is a technique through which the rain is captured from the roof catchments. The objective of this study was to investigate rooftop rainwater harvesting potential for domestic purposes using a samsamwater tool. This can be used in dry and wet seasonal situations based on the roof size and population density, which plays a crucial role in socioeconomic development and keeping community school welfare. Rooftop rainwater harvesting is the most reliable, easiest to access, and suitable source for water supply. This study was carried out from June 2018 to December 2019 based on a case study of three Jimma University Institute of Technology Kito furdisa campus. Since then, rainfall data, rooftop catchment, water consumption and water demand data have been used as inputs. Based on the findings, the annual rainfall is 1846 mm. The total roof size of the school is 888.32 m2 and almost the entire age of the building ranges between 5-15 years. It has been constructed of galvanized iron in which its run off coefficient is estimated at 90%. The collected data has been analyzed using different tools, including the Samsamwater RWH model, and SPSS statistics version 22. As a result, the volume of harvested rainwater was 12,826 m3/yr., which covered all non-potable water needs for 14,458 of the school population. The total yearly water requirement for a working day (182 days) and working days plus no working days (365 days) of the school is 18,606.72 and 26,759.47 m3/yr. respectively. The reliability of harvested rainwater from the rooftop for the community school can meet about 63.4 % of the water scarcity reduced by feeding for (365days). Whereas the reliability of rainwater-harvested potential is, 82% of water demand can be met by considering the schedule of working days (9 months). The average reliable for the study area is greater than 72.6% of water demand.

Experimental rooftop rainwater harvesting by shallow well infiltration – A case study from the Duna-Tisza Interfluve, Hungary

<p>In the Duna-Tisza Interfluve area, groundwater levels have declined significantly in the last decades, due to anthropogenic activities (e.g. water abstraction, canalization, and forestation) and climate change. In the past, several replenishment plans have been prepared, involving large, cross-regional technical investments, but have not been implemented due to the lack of adequate financial resources and environmental concerns. The aim of this study is to demonstrate a local scale solution by experimental research, which has several environmental and economic benefits and could contribute to ease the water shortage of the area.<br>Three approaches were used during the experimental research: (i) on-site field observations and measurements, (ii) time series analyses of the monitored data and (iii) transient numerical simulations to understand on-site processes. A field experiment was set up to lead rainwater from the roof of a family house to the dug well in the yard. Furthermore, two observation wells were established where the water level, temperature and electrical conductivity were recorded every half hour. Water samples were taken from the dug well and the monitoring wells for laboratory measurements. Precipitation was measured on a daily basis. The effects of shallow water injection on water level and water quality have been monitored for a year and the project is planned to be continued for at least one more year. In the second step, geomathematical methods have been applied to analyze time-series data and assess the effects of injected water on water levels and water quality. Moreover, a transient MODFLOW model was built (i) to evaluate the impact of the injected roof water on the groundwater level, (ii) to separate the influence of natural infiltration from the injected water, and (iii) to better understand the seasonal differences related to artificial and natural infiltration processes.<br>The obtained results can help to understand the effects of rainwater harvesting through shallow well infiltration, provide background information for further numerical simulations and contribute to expand the design of similar systems on settlement and regional level. In the Duna-Tisza Interfluve, rooftop rainwater harvesting and Managed Aquifer Recharge can be effective tools for climate change adaptation and increasing groundwater resilience.</p><p>This research is part of a project that has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 810980.</p>

Optimal Sizing of Rooftop Rainwater Harvesting Tanks for Sustainable Domestic Water Use in the West Bank, Palestine

In highly water-poor areas, rooftop rainwater harvesting (RRWH) can be used for a self-sustaining and self-reliant domestic water supply. The designing of an optimal RRWH storage tank is a key parameter to implement a reliable RRWH system. In this study, the optimal size of RRWH storage tanks in the different West Bank governorates was estimated based on monthly (all governorates) and daily (i.e., Nablus) inflow (RRWH) and outflow (domestic water demand, DWD) data. In the estimation of RRWH, five rooftop areas varying between 100 m2 and 300 m2 were selected. Moreover, the reliability of the adopting RRWH system in the different West Bank governorates was tested. Two-time series scenarios were assumed: Scenario 1, S1 (12 months, annual) and scenario 2, S2 (8 months, rainy). As a result, reliable curves for preliminary estimation of optimal RRWH storage tanks for the different West Bank governorates were obtained. Results show that the required storage tank for S1 (annual) is more than that of the S2 (rainy) one. The required storage tank to fulfill DWD is based on the average rooftop area of 150 m2, the average family members of 4.8, and the average DWD of 90 L per capita per day (L/c/d) varies between (75 m3 to 136 m3) and (24 m3 to 84 m3) for S2 for the different West Bank governorates. Further, it is found that the optimal RRWH tank size for the 150 m2 rooftop ranges between 20 m3 (in Jericho) to 75 m3 (in Salfit and Nablus) and between 20 m3 (in Jericho) to 51 m3 (in Jerusalem) for S1 and S2 scenarios, respectively. Finally, results show that the implementation of an RRWH system for a rooftop area of 150 m2 and family members of 4.8 is reliable for all of the West Bank governorates except Jericho. Whereas, the reliability doesn’t exceed 19% for the two scenarios. However, the reduction of DWDv is highly affecting the reliability of adopting RRWH systems in Jericho (the least rainfall governorate). For instance, a family DWDv of 3.2 m3/month (25% of the average family DWDv in the West Bank) will increase the reliability at a rooftop area of 150 m2 to 51% and 76% for S1 and S2, respectively.