Present Irrigation Scenario

It is a proven fact that the crop yields increase due to irrigation. The crop yields of rain fed areas are far less than those of irrigated areas.

Since independence, Government of India has spent considerable amount of funds, time and energy on development of command area and still has not been successful in utilizing 100% of the potential created. There is always a gap between potential created and potential utilized. This could be due to following reasons:

Lower utilization of irrigation potential results in lesser area cover than what is targeted within the same quantum of available water. This has ultimately resulted in poor recoveries of water charges and also lower water use efficiencies.For efficient performance of an irrigation system, it is necessary that the system should be self sustainable. In order to make them self sustainable, improvement in the efficiencies of water distribution systems is essential. This is possible only by the modernization of canal command areas through adoption of piping networks/MIS.

Drawbacks / Challenges of existing Irrigation System / Canal Systems:

All the water taken from a source does not reach the root zone of the plants. A part of the water is lost during transportation through canals and fields. Only part of the water is used efficiently, the rest of the water is lost. The irrigation water losses in canals are due to evaporation from the water surface, deep percolation to soil layers underneath the canals, seepage through the bunds of the canals, bund breaks, run-off in drains etc. below table gives details of conveyance losses in canal networks.

i) Wastage of Water: The water wastages in the canal systems are due to deep percolation losses, seepage losses, evaporation losses, leakages and over-topping of canals etc. These wastages ultimately result in lower water use efficiencies and lower utilization of irrigation potential created. This lower utilization of potential results in an additional burden on the water user associations and hence this results in poor recovery of water charges and electrical charges. Therefore this becomes the reason for making this into an unviable project.

ii) Excessive Use of Water: In some cases like Paddy, Sugarcane or even Banana, farmers over irrigate the crops. Such over irrigation not only results in water wastages but also leads to soil degradation and infertility. This ultimately gives lower productivity of crops per drop of water. Therefore there are often poor recoveries of water charges due to which the project maintenance becomes very difficult. This ultimately results in unviable projects.

iii) Unreliable Water Supply: In canal command areas, water supply is often not reliable and may be supplied at the whims of the ‘Valve man’. Therefore farmers do not want to take any financial risks by investing more on cash crops and often take low income crops such as Jawar, Bajra, Wheat, Maize etc. in which they will have to invest less and take lower risk. As a result of this they get very low incomes. Consequently, the recoveries of water charges and electrical charges are lower and the project becomes unviable.

iv) Non-Uniformity of Water Application: It is observed that in canal irrigated areas, farmers having their fields at the tail end do not get water in time. This results in social injustice and therefore can lead to conflicts and not smooth functioning of the project.

v) Rotational Water Supply: Due to rotational water supply, crops suffer under stressed conditions which results in lower yields and lower incomes and therefore the project becomes unviable.

vi) Seasonal Water Supply: Many times the projects are designed based on only the kharif season or for four months. This does not allow farmers to take long duration cash crops such as Banana, Sugarcane, Grapes etc. On the contrary in such projects, due to seasonal water supply farmers tend to cultivate low income short duration crops. In such situations, for the balance period the infrastructure remains idle. Due to this operation and maintenance costs increase and the project becomes unviable.

vii) Huge water losses: Traditional canal plus flow irrigation systems have huge water losses in the form of evaporation, conveyance, seepage, surface run off and deep percolation. These losses are many times up to 50%. Hence in the traditional canal plus flow irrigation systems, efficiencies are less than 50% most of the time.

viii) Land acquisition: This is a major hurdle in construction of traditional canal systems. Many times farmers are not ready to give up their lands because they are attached to them. Even if they are ready to give it up, they demand very high compensation.

ix) Hydraulic gradient to be maintained by giving uniform slope to the fields: In canal systems, hydraulic gradient must be maintained uniformly. This costs higher. There is a huge land cut – fill while maintaining such a hydraulic gradient. In closed systems, this is not required.

x) Period of Construction: The period of construction of canal systems is longer, normally anywhere between 5 to 15 years. This results in cost escalations and also longer gestation period.

xi) More Maintenance: Because of silt in the canal and also because of vegetation growth in the canal, it requires more maintenance which results in poor efficiencies and higher costs.

xii) Shorter Effective Life: The canal systems generally has a shorter effective life because of more maintenance issues and actual poor maintenance.

Effects of current irrigation methods:

1) Due to one or the other reasons listed above, the utilization of the irrigation potential created is less in the country. There is a huge gap between the irrigation potential created and irrigation potential utilized in the country and this gap is increasing day by day. The plan-wise irrigation potential created and utilized is given in the following graph. It can be seen that the irrigation potential utilized is less than the irrigation potential created. Despite significant progress in the creation of irrigation potential, under-utilisation continues to persist. Hence it is necessary to focus on the on farm irrigation in order to utilize huge irrigation potential created in the country. The Command Area Development Programme (CADP), in operation since 1974-75, particularly aims at bridging the gap between potential created and its utilisation. The programme also includes measures to install sprinkler & drip irrigation and the farmers ‘participation in irrigation water management. We need to correct this situation by focusing on development of command areas and also by undertaking on-field irrigation works on a war footing.

2) It can be observed that this has also resulted in poor productivity levels in case of canal irrigated areas as compared to well irrigated areas. In well irrigated areas, the productivities are better due to reliable water supply and demand based water supply. The farmers are able to irrigate their fields as and when required by the crops due to tremendous flexibility they have in case of well irrigated areas.