Rod-Kohi System Management and Development Programme
INTRODUCTION
Major
Rod Kohi areas traversed by hill torrents constitute nearly 65 percent of the
total area of Pakistan and encompass entire Balochistan i.e. (Makran coastal
Basin and Kharan closed Desert Basin). The other major hill torrent areas
include D.G.Khan and D.I.Khan, FATA and AJK. In Sindh province, the systems are
spread in Dadu district (Kirthar range). There are around 17.13 million acres as
the potential area under hill torrent / Rod-Kohi / Sailaba fanning excluding
riverine areas.
Indigenous Spate Irrigation/ hill torrent-irrigation systems traditionally called Rod-Kohi. Rod means water channel and Kohi pertains to mountains. In these areas major constraint is the use of flood flow which is highly variable in quantity and distribution, both in time and space. Annual rainfall is low, uncertain and patchy. Flow is laden with high silt in each flood. It is unfortunate that inspite of scarcity of water, major part of flood flows is lost due to mismanagement. Spate irrigation often takes place in environments that are arid and remote. Poverty in these areas is a major issue. There are very few options for generating income and improvement of livelihood. Abject poverty in the areas affected by the Rod-Kohi water calls for a rational and scientific management of flood flows.
Rod-Kohi or hill torrent cultivation is a unique system of agriculture being practiced in all the four provinces. In NWFP, D.I.Khan tract represents the major part of the system fed by five large tributaries locally named as "Zams". In the Punjab, major part of the system falls in the districts of D.G.Khan, Rajanpur and Jampur. In Balochistan, this system falls in the districts of Barkhan, Musakhail, Loralai, Zhob, Bolan and Lasbella. In Sindh province; the system is spread in Dadu & Larkana district (Kirthar range). The largest area under the system of agriculture lies in Balochistan.
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Potential for Development |
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Provinces |
Potential Area*(MA) | Potential Water*(MAP) | Ratio of Water to Area (acre feet/acre) |
| Federal | 0.67 | 2.84 | 4.2 |
| NWFP | 2.13 | 4.56 | 2.1 |
| Punjab | 1.41 | 2.71 | 1.9 |
| Sind | 1.36 | 0.72 | 0.5 |
| Blochistan | 11.56 | 7.85 | 0.7 |
| Total | 17.13 | 18.68 | 1.1 |
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*Master feasibility studies for flood Management of Hill Torrents, NESPAK. 1998. |
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Spate
Irrigation is traditionally used system for diverting hill torrents into
cultivable command areas for growing seasonal crops. The farming system is
characterized by extreme events of floods and droughts. It usually entails the
construction of an earthen diversion weir across the torrent with large channel
on one or both sides of the river to convey flood water across large distances.
These earthen diversion structures and water conveyance system has traditionally
been constructed by the beneficiaries / communities themselves, making use of
traditional technology. Farmers construct field by making embankments from 3 to
6 feet high to store the water depending upon the soil type, share in water and
various other factors. Upon drying crops are sown which thrive on the moisture
stored in the soil. There is no further irrigation except rains, if any occurs.
The economic significance of Rod-Kohi Irrigation agriculture is centered arround
subsistence agriculture and live-stock raising which are the main sources of
income.
Another aspect of the Spate Irrigation System of Rod-Kohi areas is the occurrence of the perennial water (known as Kalapani), which is available throughout the year in the upper reaches. It contributes significantly to sustainable farming in the area and used for high value crops like fodder, fruits and vegetables. The development potential in Rod-Kohi Hill torrent areas is listed below.
ACTIVITIES
The institute had initiated a project during 1994-95 in Rod-Kohi areas based on comprehensive and integrated approach for development and management of Rod-Kohi Irrigation system for varying climatic zones spread in Sulaiman and Kirther ranges. Project activities were mainly based on significance of indigenous Rod-Kohi systems to water and agricultural productivity. Different types of interventions were successfully tested and adapted with the participation of local communities. Emphasis was given on technologies related to improvement of water conveyance system, distribution, diversion and water application structure. The local communities not only evaluate the feasibility and cost effectively of the technologies but adopted the successful technologies. Following interventions were carried out in different climatic zones of Pakistan.
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Remodeling of
Rod-Kohi Conveyance Irrigation. |
Rehabilted Water conveyance Irrigation System |
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Water Distribution Structures. Most critical element in managing Rod-Kohi System is diversion and distribution structures, which perform both under low-and high flows and provide equitable water according to their water rights. The structures were constructed using different construction material with the participation of local communities at D.I. Khan and Barkhan Target Areas and performed satisfactorily to allow discharge of around 150 to 230 cusecs. Cost of these structures ranged between Rs. 10000 and Rs. 20000. Farmers shared about 50% costs of these experimental structures.
Efforts are under way to reduce the cost further especially for the resource poor farmers for the large scale adoption of On Farm Water Management (OFWM). |
Brick Masonary Water Distribution Structure |
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The structures helped farmers to regulate floodwater at desired level without any extra labor and time. Water distribution structures were most successful intervention in the Barkhan Target Area among the water users as farmers were facing acute problems and conflicts due to distribution of water at the diversion point according to their water rights. |
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Water Application Structures
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The cultivated fields in Rod-Kohi Irrigation System are large to the extent of 8 - 10 acres or more. The water application to the fields is crucial to control water in the flood season. Cost effective water application structures using brick masonry and pre-casted pipe nacca structure have been developed. Different designs capacities and construction materials were used. The structures were constructed on the basis of cost effectively, feasibility, adaptability and farmers perception. The cost of brick masonary structures ranges between Rs. 1500 - 5000 per structures. The structure allows safe flow of 20 - 70 cusecs discharge. Pre-cost pipe Nacca is a control device which is used to divert desired amount of water to the fields. Nacca lids are easy to operate and vandalism is much less compared to wooden planks. |
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The pre-caste Nacca of different diameters were used to construct appropriate structure for spate irrigation systems using brick masonary with number of pipes considering the area to be irrigated and amount of water required in a short period. The cost of structure varies from Rs. 1800 to 4000 with a capacity of 10 - 20 cusecs depending upon the number and size of the structures. The farmers are now adapting this technology to irrigate field to field and as water disposal structure with little modified construction approach |
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Water Diversion
Structures |
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After successful introduction of sustainable water management system at the command level, efforts were initiated to address the larger issue being faced by farmers, which is the main diversion structure. The effort was made to reduce the drudgery and unreliability associated with the construction and operation of earthen bund (Ghundi) to divert water to command area i.e. from secondary channels to the tertiary canal system. Steel gates were installed to regulate and divert water. The regulating structure will replace the earthen bund and farmers will not require constructing earthen bund for each irrigation turn. The cost of gated water diversion structure ranged from Rs. 30,000 to 125,000 depending upon the number of gates. The structures have capacity to pass the discharge from 80 to 240 cusecs depending upon the number of gates. The economics of the structure may be calculated in respect of the command area cropped and assessment of benefits compared to existing returns and cropped area watered. The most important element in the Rod-Kohi Irrigation System which enhanced through these structures is the reliability and availability of flood water. |
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Scientists
1- Mr. Zaheer-ul-Ikram,
Senior Engineer/Program Leader
2- Mr. Abdul Wahab, SO
3. Mr. Irfan Ali, SO
Contacts Details:
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Mr. Zaheer-ul-Ikram, SE/PL |
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WRRI, NARC, Park Road, Islamabad. Ph. No. 051-9255395, 051-9255012/Ext 3103 |
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[Last updated: March, 2008]
