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To mark World Water Day, held annually on
March 22, we need to renew our commitment to the restoration of our
damaged watersheds, from which water flows into the rivers to be used for
many purposes.
We are fortunate that many Indonesian provinces are blessed with a wet
climate; so we have abundant water. The distribution of water, spatially
and temporally, however, often does not match our needs. In some areas,
annual rainfall is too low, while in some areas it is too high. In the
dry season, the volume of water is less than our needs. On the contrary,
in the rainy season there is too much water, causing erosion,
sedimentation, floods and landslides.
To exacerbate the problem of water quantity, we also face the problem of
quality, that is, pollution. In many places, mostly cities, our water is
so polluted that it is not suitable for many purposes.
Water is a renewable resource. After being used, water will flow back
into rivers and be part of the hydrological cycle, which has no political
boundary.
Water that evaporates in a country may be blown away by wind and fall as
rain or snow in other countries. Large rivers, like the Nile, flow
through several countries. Managing those rivers requires cooperation
between the countries that the rivers flow. Without cooperation conflicts
occur and all affected countries will suffer. It is not surprising that
the United Nations has declared 2013 the International Year of Water
Cooperation.
Indonesia has many rivers flowing through several provinces. Cooperation
among provinces is required to manage those rivers as well as the
watershed, or land from which the water flows into the rivers.
Mismanagement of upstream water catchment will have a detrimental
downstream impact.
We have designated certain areas to protect hydrological cycles.
According to Presidential Decree No. 32/1990, a forest area with an
altitude of 2,000 meters (m) and above is categorized as protected forest
and cannot be cut. The lands surrounding water springs (200 m width),
lakes (50-100 m width) and along river banks are also categorized as
protected areas. The width of the protected river bank is 100 m for large
rivers and 50 m for small rivers outside the settlement, while for rivers
in settlement areas, the width of protected river banks is 10-15 m.
Another protected area is one that has high rainfall and soil structure
capable of absorbing a large quantity of water. In addition, land having
3 m-depth peat is also protected.
By protecting those areas, we maintain the hydrological function of the
ecosystem. When water falls as rain on forested land, it will take
several paths. Some is intercepted by vegetation and evaporated again in
the atmosphere, some is absorbed by humus or decomposed leaf litter, some
infiltrates the soil and some will run off or flow on the land surface.
Forest soil and humus retain the water and release it slowly, so the
water keeps flowing in the water spring during the dry season. A study in
the Ivory Coast found that rivers flowing from primary forests had twice
as much water as those flowing through coffee plantations in the middle
of the dry season and five times more at the end of the dry season.
Forested lands not only reduce flooding in the rainy season and
prevent drought in the dry season, but also act as a natural water
treatment plant. The water spring from forested land is relatively clean.
The government of New York City calculated that to get clean water,
maintaining the forest ecosystem in catchment areas is much cheaper than
installing and operating water treatment plants. So, they decided to
invest millions of dollars to protect the watershed instead of spending
billions of dollars for water treatment plants. They worked hard to make
the New York City watershed memorandum of agreement, signed by New York
City, New York state, upstate towns comprising the watershed and various
environmental groups.
The agreement contains land use regulation for the watershed and various
programs to protect the watershed funded by the city. As a result, the
New York City watershed provides approximately 1.3 billion gallons of
clean drinking water per day for about 9 million people. This is the
largest unfiltered water supply in the United States.
(www.catskillcenter.org)
Indonesia has 458 watersheds, 60 of which are highly critical, 222
critical and 176 are potentially critical (www.antaranews.com). High
demand for land for agriculture, settlements and industry has caused
deforestation in upper water catchment areas. Without sufficient forest
coverage the watershed can no longer function to regulate water flow and
filter polluted water. The increased run off in rain results in erosion,
sedimentation, floods and landslides.
The Indonesian government has issued Government Regulation No. 37/2012 on
the management of watersheds. The regulation aims to coordinate,
integrate, synchronize and synergize the watershed management in order to
improve the carrying capacity. For the watershed of large rivers
involving two or more provinces the management falls under the Forestry
Minister in coordination with other relevant ministries, such as the
Public Works Ministry, which has specific units to manage rivers, namely
the Agencies of River Area under the Directorate General of Water
Resources.
Managing a watershed is a very challenging task, as a great portion of
land within the watershed are owned privately. We can learn from New York
City. The involved provinces and districts must work together with land
owners and environmental groups to create agreement on watershed protection.
The government must provide funds and expertise for protection programs
that give economic benefits to land owners, to ensure the effectiveness
and sustainability of the agreement.
We are blessed to have high annual rainfall. The abundant water falling
on watersheds will bring economic and ecological benefits if properly
managed. But if we fail to manage it, we will suffer economic and
ecological loss through erosion, sedimentation, floods and landslides in
the rainy season and drought in the dry season. ●
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