*3.4. Reduction in Irrigation Depths*

In the plots where the irrigation tests were carried out and the irrigation recipes calculated with Equation (4), it was possible to lower the irrigation depth by more than half, as shown in Figure 4. In general, it can be noted that the farmers have a tendency to apply more water in the plots with a loam texture (with an average of 40 cm/ha/irrigation and a maximum of 97 cm/ha/irrigation); however, after the recipe is shown and the information on the number of furrows per irrigation to be applied is given, this irrigation depth is reduced at 15 cm/ha/irrigation on average, which brings considerable savings to the irrigation district. On the other hand, in the plots with a silty clay texture, the irrigation depth applied is, on average, 19 cm/ha/irrigation.

The furrows per irrigation that must be opened depending on the flow at the entrance of the plot and the optimal flow are less than those that the farmers usually apply. This implies more work for him and sometimes he does not cooperate mainly because the payment that they receive is a function of the number of hectares they can irrigate. According to their experience, the slower they pour the water into the plots, the more plots they can serve. In this sense, in coordination with the irrigation district authorities, incentives were sought to convince the farmers to apply the irrigation recipe.

In addition, in some cases the irrigation lengths are greater than 300 m, and in these plots the irrigation depth that is applied per hectare exceed 40 cm. In Figure 4 appears atypical points, meaning that, in some plots, it has been detected that they apply almost 100 cm of depth per irrigation event. Here, they were given the recommendation to make two or three sections along their original irrigation lines.

**Figure 4.** Irrigation depth applied in a traditional and design irrigation.

The efficient design that was carried out allowed us to lower the total amount of water used in each of the studied crops. In all cases it was observed that by applying a correct design the amount of water used per growing period was reduced. Figure 5 shows the average of the evaluations carried out during the years of this study, which in general shows a reduction of 35% for barley and 48% for corn and sorghum crops. The savings obtained for the corn and sorghum crops represented 93% of the amount of water required to plant the same crop in another hectare, while in the case of barley the savings obtained in 2 ha provided enough water to plant an additional 1 ha.
