Author: Knowledge Management in CACILM Phase II, ICARDA.
Definition of technology:
Multilevel irrigation allows for consistent use of runoff from the upstream irrigation sites for irrigation of downstream sites and only runoff from furrows of the last level discharged out of the area.
Brief summary of technology:
Multilevel irrigation is an improvement of irrigation by a constant stream with the use of short-distance furrows. The irrigation site is divided into temporary longitudinal and cross-sectional irrigation ditches into several levels of irrigation furrows depending on soil conditions. The distance between levels is defined by the length of furrows. As a rule, short furrows are 40-70 m in length (Figure 1). There are several schemes of the organization of irrigation on levels. The most widespread scheme is the one, where lateral, “shokh”-ditches are made along the center of irrigation sites. Irrigation by short, 40-70 m long furrows begins from the top level. Surface runoff from the end parts of the top level is collected by an intercepting ditch – “ok-aryk”, made across furrows.
At the same time, water for irrigation of the next level is supplied into this ok-aryk. The volume of this water is reduced by a value of runoff from the first level. The runoff from the second level is collected by the next ok-aryk, which was made similar to the first one. Additional water to this ok-aryk is supplied from the shokharyk, which was made parallel to the furrows. The runoff from only the last level is not used for irrigation and discharged out of the area.
Water-saving effect is seen in reduction of water losses as surface runoff by 15-20% (from water supply) as unused surface runoff in the irrigated area is formed only in the last level. In a zone of moderate and steep slopes under multilevel arrangement of fields and irrigation ditches the surface runoff from upstream fields is directed to downstream irrigation ditches. Water use efficiency under the multilevel scheme of irrigation in the areas of largescale agricultural enterprises is close to 1.
Location: Postdargom district, Samarkand province.
Area of technology application: 10 ha.
Stage of intervention: prevention / mitigation of land degradation.
Main land use issues and the main causes of land degradation:
In the current conditions, considerable part of the irrigation water supplied to the field is used irrationally, "gross" norms substantially exceed the norms of water consumption of agricultural crops, huge losses of surface runoff out of irrigated fields and for infiltration below plant root zone are observed everywhere.
Main technical features of technology:
Interception of surface runoff during irrigation, creation of optimal soil moisture in the fields, increase of irrigation efficiency.
Type of land use Conservation measures
Irrigated arable land.
Production of annual crops - Во(Ca).
Agronomic and irrigation methods.
Average annual rainfall: 200-420 mm.
Altitude (meter above sea level): 300-400 m.
Landscape: foothills, plains.
Slope (%): 2% (10).
Soil fertility: from 40 to 90 points of bonitet.
Humus content in arable horizon: 0.8-1.5%.
Natural soil drainage/infiltration: moderate.
Size of land area (ha): 30-50 ha.
Land ownership: long term lease.
Water use rights: through WUAs and irrigation management bodies.
Market orientation: Mixed farming (subsistence and commercial).
Impact of technology
- water saving does not demand additional capital investments;
- reduction of unproductive water losses during irrigation;
- saving of irrigation water by 15-20%;
- increase of water use efficiency in the areas of largescale enterprises close to 1.
- demands skills or higher qualification of an irrigator.
Acceptance/adoption of technology: the technology is applied by more experienced farmers. For wider implementation of the technology increased awareness and training are necessary.
1. Recommendations on the optimum combination of elements of irrigation technique along furrows for various conditions of the Fergana Valley. The project "IWRM - Fergana" - "Improvement of water use efficiency in the field level" - "WPI-PL" A.A. Abirov, V.G. Nasonov.
2. Water-saving technologies in farms. Project " IWRM - Fergana", Tashkent, 2009. M.G. Horst, S.A. Nerozin.
Name of person(s) collected this description: Tatyana Hamzina, Chief specialist on soil reclamation studies and irrigation regime. UZGIP LTD.
Address: 44, Navoi str., Tashkent, Uzbekistan.
Tel.: +998 90 9945654