Potential Benefits from Sharing Rainwater Storages Depending on Characteristics in Demand

A rainwater harvesting system (RWHS) is an alternative water resource that collects and stores rainwater from rooftops. It helps smooth out variations in water supply and sustainable water resources management. In this study, we investigated the potential benefits from sharing RWHS with nearby neighbors in a community. We introduced different mean, variance, and correlation in water demand for each water user. A simple case of a community composed of four prospective users is introduced to investigate the benefit from sharing RWHSs. Using the historical rainfall records from four catchments in South Korea, a storage-reliability-yield analysis is applied to obtain the required storage and corresponding reliability for a given yield ratio. The results indicate that the required total storage is reduced when RWHSs are shared among users and the rate of reduction is proportional to the degree of sharing. The required total storage was reduced down to 61% compared to the original storage when RWHSs are shared for a target reliability of 80%. The benefit from sharing also depends on the demands, which are different among users. Test cases with different means and variances as well as correlation disclose the conditions when the benefit from sharing RWHSs is maximized. The result showed that difference in mean and variance additionally reduces the required storage up to 3% and correlation in demand also as much affects the required storage.

[1]  V. G. Mitchell How important is the selection of computational analysis method to the accuracy of rainwater tank behaviour modelling? , 2007 .

[2]  Patricia Gober,et al.  Climate Variability and Residential Water Use in the City of Phoenix, Arizona , 2007 .

[3]  Amimul Ahsan,et al.  Reliability analysis of rainwater tanks in Melbourne using daily water balance model , 2011 .

[4]  Ataur Rahman,et al.  Reliability analysis of rainwater tanks : a comparison between South-East and Central Melbourne , 2012 .

[5]  Ataur Rahman,et al.  Reliability and cost analysis of a rainwater harvesting system in peri-urban regions of Greater Sydney, Australia , 2014 .

[6]  A. Fewkes Modelling the performance of rainwater collection systems: towards a generalised approach , 2000 .

[7]  Chun-Hung Lin,et al.  A probabilistic approach to rainwater harvesting systems design and evaluation , 2009 .

[8]  D. Aklog,et al.  Reliability-based optimal design of water distribution networks , 2003 .

[9]  Charles D.D. Howard,et al.  Theory of Storage and Treatment-Plant Overflows , 1976 .

[10]  Brian W. Baetz,et al.  Sizing of Rainwater Storage Units for Green Building Applications , 2007 .

[11]  Daniel P. Loucks,et al.  Reliability, resiliency, and vulnerability criteria for water resource system performance evaluation , 1982 .

[12]  Upmanu Lall,et al.  A rainwater harvesting system reliability model based on nonparametric stochastic rainfall generator , 2010 .

[13]  Tiku T. Tanyimboh,et al.  Peaking demand factor-based reliability analysis of water distribution systems , 2005, Adv. Eng. Softw..

[14]  Chao-Hsien Liaw,et al.  OPTIMUM STORAGE VOLUME OF ROOFTOP RAIN WATER HARVESTING SYSTEMS FOR DOMESTIC USE 1 , 2004 .

[15]  Art Ludwig Water Storage: Tanks, Cisterns, Aquifers, and Ponds for Domestic Supply, Fire and Emergency Use--Includes How to Make Ferrocement Water Tanks , 2009 .

[16]  Yongwon Seo,et al.  Effect of connecting rain barrels on the storage size reduction , 2012 .

[17]  J. Rockström,et al.  Risk analysis and economic viability of water harvesting for supplemental irrigation in semi-arid Burkina Faso and Kenya , 2005 .

[18]  B. Adams,et al.  Urban Stormwater Management Planning with Analytical Probabilistic Models , 2000 .

[19]  G. Daigger Evolving Urban Water and Residuals Management Paradigms: Water Reclamation and Reuse, Decentralization, and Resource Recovery , 2009, Water environment research : a research publication of the Water Environment Federation.

[20]  David R. Maidment,et al.  Time patterns of water use in six Texas cities , 1984 .

[21]  Arnold Pacey,et al.  Rainwater Harvesting: The Collection of Rainfall and Runoff in Rural Areas , 1986 .

[22]  Ataur Rahman,et al.  Rainwater harvesting in Greater Sydney : water savings, reliability and economic benefits , 2012 .

[23]  R. Vogel,et al.  Generalized Storage-Reliability-Yield Equations for Rainwater Harvesting Systems , 2009 .

[24]  F. Abdulla,et al.  Roof rainwater harvesting systems for household water supply in Jordan , 2009 .

[25]  Andrew M. Dixon,et al.  Analysis of a rainwater collection system for domestic water supply in Ringdansen, Norrköping, Sweden , 2005 .

[26]  R. Vogel,et al.  Global Storage-Reliability-Yield Relationships for Water Supply Reservoirs , 2015, Water Resources Management.

[27]  Enedir Ghisi,et al.  Rainwater tank capacity and potential for potable water savings by using rainwater in the residential sector of southeastern Brazil , 2007 .

[28]  Chengchao Xu,et al.  Reliability-Based Optimal Design of Water Distribution Networks , 2001 .

[29]  G. V. Loganathan,et al.  Effects of Urbanization on Frequencies of Overflows and Pollutant Loadings From Storm Sewer Overflows: A Derived Distribution Approach , 1984 .

[30]  Young-Oh Kim,et al.  The impact of climate change on the benefit of a rain barrel sharing network , 2013 .

[31]  Robert A. Young,et al.  Price elasticity of demand for municipal water: A case study of Tucson, Arizona , 1973 .