Warning: Creating default object from empty value in /afs/ir.stanford.edu/group/womenscourage/cgi-bin/blogs/wpmu-settings.php on line 45
Tapping New Resources, Quite Literally » Women's Courage

Tapping New Resources, Quite Literally

February 24th, 2011 by labrian Leave a reply »

As more recognition has been given to the importance of clean water, the new millennium has seen a surge in new technologies designed to increase water access in the developing world.  When combined with gender mainstreaming programs that empower local women’s say in their community’s decision-making process, these creative technological solutions can have a great impact on both improving water access and gender equity.  This blog will give an overview of one of these technologies, and point to examples in the developing world where it has achieved success.

Rainwater Harvesting

A 2006 news report for the UN stated that the rainfalls of some African countries — such as Kenya and Ethiopia — have the potential to meeting their populations’ water needs by 6-7 times their current populations.  Rainwater harvesting thus holds massive potential for improving water access there (1).  This relatively simple and adaptable technology does exactly what the name suggests: capturing and storing rainwater from rooftops, land surfaces, or rock catchments and then letting it collect in a storage facilities that range from cement tanks that can hold up to 100,000 liters of water (1) to various jars and pots.  Although there are many ways that the water leeches out of the Earth, rainfall is the only way that water is returned to our ecosystem.  In its purest form, rainwater is relatively clean and cost-effective to collect, which provides a cheap way to provide an alternative form of water in poorer areas.  Rainwater collection gives houses and/or communities a nearby source of water that they can then use for a myriad of purposes, including drinking, washing, irrigation, livestock watering, and gardens.  All of these have positive impacts on nutrition and net income (2).  One very common way in which rainwater collecting is accomplished is through roofwater harvesting, where rainwater drains off the edge of a roof (either with the use of gutters or without) and then drains into storage bin.  In order to actually implement these kinds of technologies, though, the roofs themselves need to be made from impermeable materials, such as iron sheets or tiles.  Rainfall must also be equal to 50 mm/month for half the year, and there should be another ground water source nearby with which to supplement (3).  Once implemented, though, the water collected from roofwater harvesting meets WHO water quality standards, and does not need any further treatment.  Roofwater harvesting can be adapted depending on the need of the community and installed on the roofs of hospitals, schools, and houses alike.  And contrary to other more bureaucratic forms of water access, maintenance of roofwater systems relies on houseowners themselves.

Land and rock catchment systems rely on increasing the amount of water runoff that is able to be collected through installing drain pipes at the ground level.  While less complex, this form of rainwater harvesting also increases the chances that more water runoff will be lost through water absorption in the earth.  Water quality might also not be quite as good, so this type of rainwater harvesting is best suited for irrigation and agricultural purposes (4).

The storage bin itself can be made out of a variety of materials and come in many different sizes.  The conveyance system, however, takes a little more thought in terms of its design.  Because the initial rainwater will carry debris with it and it not as clean, there needs to be a way to direct the initial rainwater away from the storage bin.  This can be done manually, through a down-pipe flap, or automatically, although this way requires a greater technological and financial investment (6).

If implemented successfully, rainwater harvesting can improve a variety of public sectors.  Provisioning ecosystem ecosystem services can increase agricultural productivity, food supply, domestic income, fodder for livestock and rainfall infiltration; regenerate landscapes; and improve productive habits and diversity species.  Regulating ecosystems reduces negative environmental effects of flooding and soil erosion, and provides a hedge during dry-spells.  All of these impacts can help achieve the Millennium Goals (7).

Potential issues associated with rainwater harvesting include the volatility of rainfall, as well as the existence of roofs on which rainwater can be collected.

Yet, there are other forms in which rainwater harvesting can take place, although I will not have time to touch on them extensively in this blog.  Rainwater can be collected in the soil itself, sub-surface dams, wells, and ponds, as well as cisterns.  These form the basis for more agricultural, rather than domestic, use.

As climate change begins to impact the globe to a greater extent, we will have to rely on innovative solutions like these more and more.  Although there are still problems associated with rainwater harvesting that must be worked out, all signs point to great potential for using rainwater to our advantage.  By ensuring that women are included in the process of implementing these technologies, gender equity can also be established.

Works Cited:

1) http://www.un.org/apps/news/story.asp?NewsID=20581&Cr=unep&Cr1=water

2) https://thewaterproject.org/rain_catchment.asp

3)  http://www.unep.org/gc/gcss-viii/Kenya-IWRM.pdf

4) http://www.ircsa.org/factsheets/lowincome.htm

5) http://www.gdrc.org/uem/water/rainwater/introduction.html

6) http://www.gdrc.org/uem/water/rainwater/introduction.html

7) http://www.unep.org/Themes/Freshwater/PDF/Rainwater_Harvesting_090310b.pdf

Advertisement

Leave a Reply

You must be logged in to post a comment.