Newsletter and Technical Publications
<Sourcebook
of Alternative Technologies for Freshwater Augumentation in Some
Countries in Asia>
1.3 Coconut Pick-ups
Technical Description
In South India, coconut pick-ups is a name popularly used for weirs
constructed exclusively to provide water to coconut gardens. These weirs
or pick-ups are small structures built across the seasonal or perennial
streams to slow the flow of water at an appropriate location. This results
in surface water storage, groundwater recharge, reduction of soil erosion
and availability of water for other purposes. The bunds that form the
puck-ips are constructed of locally available materials such as stones,
boulders or mud turfed with grass. The bunds are usually built within the
water course almost to the height of the surrounding ground level,
depending upon the width and steepness of the stream. When stream flows
occur, the coconut plantation, situated within the floodplain on either
side of the water course, is temporarily flooded. The water impounded by
the structures recedes within 3 to 4 days, with the excess water
frequently diverted into a tank or cistern. Sometimes there will be
several coconut pick-ups within a catchment, and several tanks which may
flow from one tank to the other.
Extent of Use
This technology has been used in many places in South India.
Operation and Maintenance
The pick-up is constructed by the farmers and hence both operation and
maintenance is the responsibility of the user. The principle maintenance
requirement is keeping the pick-up sealed to prevent loss due to leakage.
Level of Involvement
Usually, the pick-ups are managed by the users who build them. Repair
and maintenance are also carried out by the user. Government may be
involved in the funding of the pick-ups, and in the initial permitting of
the project site. This function is commonly performed by the local
self-governing body that functions as a farmers/users association and
manage their activities.
Costs
Construction of a typical coconut pick-up for an area of 10 ha in India
would cost about $2 000.
Effectiveness of the Technology
The technology is successful in providing adequate water to many coconut
farmers for agricultural purposes.
Suitability
The technology is suitable for use in tropical areas with moderately
rolling topography and small streams.
Advantages
The use of pick-ups encourages groundwater recharge by promoting
infiltration and vertical percolation. This recharge helps to sustain
yields to percolation tanks and tube wells supplying open tanks. The
recharge of open wells is almost immediate, even at a distance of up to
0.5 km depending on soil structure and gradients.
Ponds created by the pick-ups can serve also as a drinking water source
for livestock from up to 10 villages.
Further, the floodwaters deposit a few millimetres of silt behind the
pick-up structure and enrich the soils of the floodplains behind the
pick-up with nutrients associated with materials like manure, leaves and
other terrestrial debris carried in the runoff flows. These minerals and
nutrients enrich the soil particularly during the monsoon season without
the use of fertilizer supplements.
Disadvantages
The presence of the temporary ponds behind the pick-ups can promote
mosquito growth and exacerbate human health risks.
Cultural Acceptability
Being a traditional technology, the use of pick-ups is culturally
acceptable. Some religious functions are held in the pick-up areas.
Further Development of the Technology
More realistic predictions of sustainable water yields will be needed to
design cost effective and adequately-sized bunds.
Information Sources
Abdel-Rahman, H.A. and I.M. Abdel-Magid 1993. Water conservation in
Oman. Water International,. 18 (2): 95-102.
Asian Development Bank (ADB) 1993. Water Utilities Data Book: Asian
and Pacific Region. ADB, Manila.
Asian Institute of Technology (AIT) 1982. Evaporation Control Using
Monomelecular Organic Surface Films, AIT Research Report No. 1982-2.
Division of Water Resources Engineering, AIT, Bangkok.
Bhatia, R., P. Rogers, J. Briscoe, B. Sinha, and R. Cestti 1994.
Water Conservation and Pollution Control in Indian Industries: How to Use
Water Tariffs, Pollution Charges and Fiscal Incentives. UNDP-World
Bank, New York.
Frederick, K.D. 1992. Balancing Water Demand with Supplies, The Role
of Management in a World of Increasing Scarcity. World Bank Technical
Paper No. 189. The World Bank, Washington, DC.
Gracy, C.P., B.L. Chinanda, C.K. Jalajakshi, and K.H. Vedini 1995
Traditional Methods of Soil and Water Conservation - A Case of Coconut
Pickups. In: Proceedings of the National Workshop on
Traditional Water Management for Tanks and Ponds. Centre of Water
Resources and Ocean Management, Anna University, Madras.
Sasekumar, A, N. Marshall, and D.J. Macintosh, Eds 1994. Integrated
Planning and Management of Freshwater Habitats, including Wetlands. In:
Ecology and Conservation of Southeast Asian Marine and Freshwater
Environments including Wetlands. Kuala Lumpur, Malaysia. pp. 311-322.
Vigneswaran, S., et al. 1989. Low Waste Technologies in
Selected Industries. Environmental Sanitation Reviews No. 27,
Environmental Sanitation Information Centre, Asian Institute of
Technology, Bangkok.
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