RESULTS AND DISCUSSIONS -Determination of the existing condition of water supply condition in Magsaysay Elementary School. The first objective of the study was to determine the water supply condition in the school of Magsaysay. Data of water supply and consumption were gathered from the school, a total maximum water consumption of 68m³ was recorded before the covid-19 crise occurred, and a maximum of 22m³ was recorded during the face to face limited classes. this high-water consumption was almost fully supplying by the Baguio Water District, and only a small portion was supplied by the rain and used for water gardening, consumed by 215 male students and 239 female students. By taking advantage of the rainwater, the school could reduce the burden on the Baguio Water District and use the harvested water for all non-potable proposes. -Determination of the the design considerations in the rainwater harvesting system The second objective is to design the rainwater harvesting system, a calculation of first the precipitation annual average to determine the amount of water that can be harvested, proceeding with the catchment area and the piping system and ending up with the storage tank. A daily Rainfall data from 2008 to 2021 was collected from PAG ASA as presented in Fig. 1 THE MONTHELY PRECIPITATION AVERAGE FROM 2008 TO 2021 1200 1000 989,42 800 732,46 600 540,97 529,49 400 344,43 379,66 200 0 20,64 27,9 52,65 JAN FEB MAR 119,87 APRIL MAY Series 1 JUN JUL Column1 Figure 1 AUG SEP Column2 OCT 80,86 45,69 NOV DEC As we see in the presentation that the month of August comes with the highest rate of rainfall of 989.42mm, we can also notice the actual average start of the rainy season which is from May or June until October. Table 1: Annual precipitation from 2008 to 2021. Yearly average precipitation in the period of 2008 to 2022 Year Precipitation average 2008 349.90mm 2009 511.50mm 2010 266.80mm 2011 336.80mm 2012 386.60mm 2013 269.95mm 2014 242.58mm 2015 405.98mm 2016 246.11mm 2017 232.62mm 2018 451.32mm 2019 313.15mm 2020 196.6mm 2021 383.52mm Average 329mm/year Roughly speaking, 1 millimetre of rain over 1 square metre of roof equals 1 litre of water. Water supply = rainfall ave. x catchment area Catchment area = 28m x 12m = 336sm² the maximum volume of water that can be harvested = Roof area (in square metres) x Annual average rainfall (in millimetres) = Maximum rain harvesting capacity (in litres). Required tank capacity = 336m² x 329mm/year x 0.9 = 99,489.6 liters = 99.489m³/year Required tank capacity = 99.489m³/year ÷ 12 = 8.3m³/month Based on the calculated values the required tank capacity is 9m³ that may store water accumulated by a 336m² catchment area. Catchment area The targeted catchment area to be used is the court shade of the school that comes with a dimension of 28m by 12m, and a coefficient of 0.90. a rectangular perfect in size and with a good slope that will direct the runoff water to a wide 6’’ gutter that could be able to contain a high amount of water in case of a heavy rain. Pipe system. Two big punches of holes or downpours will be installed at the width side of the shade’s gutter to direct all the amount of the water from the higher elevated gutter side to the lower side, collect all the harvested water in one big storage tank at one side. This were done in order to avoid installing two tanks in both sides of the catchment due to the long distance between the two sides, and also due to the limited space available. A 4 in. x 10ft. 220PSI PVC pipes were used to deliver the rainwater from the catchment area to the storage tank. Storage tank. A 9m³ storage tank was installed at the side of the gutter’s downpours for a shorter travelling distance for the water. What to avoid. The process of installing a water harvesting system have to be as simple as possible to maintain a smooth flow of the water, and we must also aim for a good and clean condition of water storage. In order to achieve our goals, ensure these parameters must be addressed, and it is stated as the following: 1- Avoiding the first flush coming from the catchment is preferable in order to reduce the sediments at the bottom of the tank. 2- Covering the downspouts with two net screens with different measures will help sieving unwanted objects and filter the water. 3- Try the keep the tank away from sunlight to avoid algae growth, if its impossible then it is better to have a dark tank or paint the tank with black. 4- Avoid screening the gutters itself, only the downspouts. 5- Make sure that the tank is well covered to avoid insects or any contamination to reach the water. Conclusion and recommendation The implementation of the rain water harvesting system based on the data and the calculation given could be a great solution and a convenient alternative source of water that could supply the school with an extra free amount of water that could be added to the main water supply and provide adequate and safe clean water for handwashing, toilet use, menstrual hygiene management, and cleaning purposes available to all students during school hours. The cistren tank were designed with a volume of 9m³ that could contain up to 329m³ annually, this water that was accumulated from a 336m² catchment area will reach the storage tank via a 4 in. x 10ft. 220PSI PVC pipes that is connected to a 6’’ wide gutters with two drainages from the 12m side of the catchment area. Recommendation Social bias might exist Since harvesting the rain water is advised by the city office and authorized department of the city, but when harvesting is commonly promoted and encouraged by different parties also and its benefits are discussed and advertised widely on how it is useful to us and to the environment as well, this might increase the number of not only the schools but also the residents to install a rainwater harvesting system and lift the burden a bit on Baguio Water District and try to make use of the enormous amount of water that falls on Baguio every year. We also recommend the school itself to have a committee to maintain the water harvesting facility for its operation and maintenance once it is constructed. Acknowledgment All the glory and thankfulness to god who subvention us with power and patience to complete this work. We would also like to thank those whom without, this work wouldn’t be done as it is now. Thus, the authors would like to acknowledge them for their support and guidance: Engr. Jeferd Saong, the dean of the school of Engineering and Artemethers for his guidance and support all through the time of preparation of this paper. Engr. Maria Clarissa joy Ordoño, for her guidance and support as an instructor and an advisor also. Engr. Shackile Asuncion, for his valuable comments and criticisms that allowed us to see the path clearly. Engr. Gaudencio T. Tiwing, for his priceless help and advices that he provided at the most critical time we needed it as an advisor. Miss. Florida F. Cail,EdD, the principal of the Magsaysay Elementary school for her acceptance who had made a great effect for this project to be done. Mr. Samuel D. Lachica, physical facilities coordinator of the Magsaysay Elementary school for providing the necessary data needed to complete the project. Engr. Jasmin G. Madayag, an Engineer at the University of Baguio, for her advises and criticisms as one of the panelists. Engr. Daves B. Guron, an Engineer at the University of Baguio, for his advises and comments as one of the panelists. Engr. Sabel Etecan, an Engineer at the University of Baguio, for her advises and comments as one of the panelists.
