Rainwater Harvesting: Harnessing an Abundant Natural Resource
The collection and filtration of rainwater could answer the increasing need for water in urban areas that is becoming more and more unaffordable for the poor
By Arlene Christy D. Lusterio
The growing demand for domestic water in urban areas and the rapid depletion of groundwater due to exploitative groundwater extraction and weak water management systems magnify the campaign to shift to rainwater harvesting.
Rainwater harvesting is a means of collecting rainwater. In the past, human settlements in Iraq, Iran, India, Israel, and Egypt collected rainwater for agricultural uses. Communities used it as a means to reduce periodic flooding due to seasonal rains, provide water for irrigation of farms, and prevent salt water intrusions in arid regions.
Rainwater harvesting can be done today in urban areas to supplement the lack of water supply for domestic use. It could also help alleviate the dwindling supply of groundwater by developing recharge wells, a system which allows rainwater to percolate back to the ground.
In urban areas in the Philippines, households collect rainwater informally without knowing how to improve the existing system. Dissemination of information on rainwater harvesting and the significant reduction it can contribute to the general water consumption will help popularize the approach.
Integration into community planning
The planning of utilities in the Philippines has never considered the inclusion of networks that facilitate rain or surface water harvesting and recharge. Water supply lines are designed with the assumption that water will be supplied by the established water district and surface run off naturally goes to drainage canals and ends up in rivers or streams as overspill. In places where no district water supply is available, groundwater extraction is the solution.
Planners and sanitary engineers need to design a sustainable system that does not only ensure water supply, but also integrates the recycling and reuse of rain and surface water run-off — two water sources that the Philippines has in abundance. Channeling these water resources to the right places could help prevent flooding in the urban areas, replenish dry wells and result in a significant reduction of domestic water demand on the municipal or city water supply line.
About the author
Architect and Environmental Planner Arlene Christy D. Lusterio is the Executive Director of TAO-Pilipinas, Inc. She recently finished her research study in South Vietnam about sustainable coastal settlements under the Asian Fellows award.
Resource Management | rp | 13 September 2007 |
