Deterministic For Rain Water Harvesting Storage Capabilities with the Design Curve Technique, A Strategy for Attaining Copiousness of Water

James NTAYOMBA, Li Xiao Ying, Etienne GASASIRA,BWIMBA MUGANGA Godfrey, Alexandre TWIRINGIYIMANA

Design curves, rainwater tank, water savings, Reliability, Quality of harvested rainwater.

Considering fecal contaminations of drinking water sources resulted from the storm runoff in the view of global access to safe drinking water, Fecal contamination varies with time while its monitoring is often rare.It is from this acumen,Rainwater harvesting systems (RWH) has become a prevalent water saving and conservation means across the world. In many cities, a pre-determined rainwater tank size is mostly selected without a detail water balance modelling at the location. Nevertheless, to attain a maximum use from a RWH system at a given location, it is required to design the scheme based on the site-specific environments (e.g., local rainfall and loss characteristics) and further pertinent design constraints. There have been limited studies on regionalization of RWH system, which can account for the spatial variability in rainfall, loss and water demand characteristics over a given region to provide site-specific design of RWH system storage capacities. This paper presents RWH approach to advance a set of design curves, which supports in the assortment of an adequate RWH system at a given location. Rwandan rainfall data from its agency Meteorological Agency across the western and northern regions are used to develop and test the proposed approach. It has been found that there is a significant variation in rainfall characteristics across the regions and that a common tank size across these regions does not present a satisfactoryresult. It has been found that a 5-kL tank can achieve a consistency (i.e., percentage of days the RWH can encounter the given demand) of 31% - 93% for four people reliant on the location in the region and the types of water used. The developed regional design curves could result in an increased water savings; Theanticipated approach can be adapted to other cities across Rwanda and the world which contemporaryhas a high rainfall slope.

https://doi.org/10.31871/IJNTR.7.6.12