Opening a Paradigm of Harvesting Rainwater

Discussion: PMKRI - Gusdurian  - Sorowajan Youth Organization

By Stube HEMAT Yogyakarta.          

Have you ever consumed rainwater? Trustha Rembaka, coordinator of Stube HEMAT Yogyakarta asked the participants of the discussion held by PMKRI Yogyakarta, Gusdurian Jogja and Karang Taruna Sorowajan at Griya Gusdurian (Saturday, 22/7/2023). This question ignited the participants' attention regarding rain, after  expressing what they thought when it rained or got wet on the rain. Some expressed that caught by the rain is disturbing, serene, annoying, triggers headaches, causes flooding, and various other answers. In addition, when the participants calculated the average water needed in one day, it was revealed that one needs at least 70 liters to 200 liters water per day! Most of the water needs are supplied from wells, PDAM, and refill water. This is the starting point of this joint discussions about whether rain is always negative and whether  it is possible to harvest rainwater.

Yes, harvesting rainwater is an alternative, because rainwater has not been much managed even though it is free, and logically rainwater is cleaner than groundwater. After all, it has not been contaminated with pollutants. Stube HEMAT Yogyakarta as a Human Resources development institution encourages young people and students to be 'literate' about water problems and the existence of water that needs to be maintained. Young people must 'plunge' into the reality of water problems, so they realize and apply it in their daily lives by using water wisely.

In the discussion, Trustha explained that water problem related to three factors, namely, Availability – the available amount of water is not a guarantee that it can be used, polluted water is not considered because it cannot be used. Access – if water is available but hard to get, then water becomes scarce. Distribution must be fair and equitable, between one community and another. Apart from that, the tendency of increasingly dense housing also has an impact on unmanaged domestic waste which will threaten water quality, especially as some participants admit that they still use well water for daily consumption.

In the next presentation, the participants looked at the steps to harvest rainwater into ready-to-drink using a connected container to electrolysis using an anode (+) in one container and a cathode (-) in a second container which is electrified in direct current (DC). Participants tested the acidity of the electrolyzed water with a pH meter and the mineral content of the water with TDS (Total Dissolved Solid), then compared it with local water. For pH, electrolyzed rainwater is at 8 and TDS is below 10 ppm while local water has a pH of 7 and TDS at 120 ppm. Both of these waters are still in the Regulation of Minister of Health 492/Menkes/Per/IV/2010, the pH standard for drinking water is 6.5 – 8.5 mg/l and the maximum Total Dissolved Solids (TDS) is 500 mg/l.

From this discussion, young people are aware of water problems, from limited water availability, to uneven access and distribution of water, so the use of rainwater for drinking water is an alternative. Rain is no longer considered a nuisance but a blessing for drinking water self-sufficiency. So, young people change the paradigm and start harvesting and consuming rainwater. ***