16 Comparative Analysis for Irrigation Water Application Methods …
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16.2.2.1 Design Criteria
The following are the general design criteria for the strips:
(1) Width
(2) Slope
(3) Length
(4) Location of levees and strips
(5) Computation of time to cover a strip (Arora 2014).
16.2.3 Furrow Irrigation Method
In furrow irrigation method water is applied to the field to be irrigated along a series of
long narrow path called furrows. This is done to avoid spreading the whole land with
water for minimization of water. In this type of surface irrigation, the furrows are dug
at intervals and at right-angles to the field channels or laterals. Water application is
dependent on the length of the furrows, water management factors and soil properties
in furrow type of irrigation. Water is being flowed into the furrows for 12–24 h during
irrigation exercise, and it can be longer or shorter depending on the aforementioned
factors. It is worth noting that, water is not spread over the whole irrigated field.
The water flowing in the furrows infiltrates the soil and spreads laterally and reaches
the roots of the plants between the furrows. As discussed earlier in furrow type
of irrigation only some portion of the land is wetted (i.e. in between the laterals),
whereas in basin and border methods the entire field is wetted directly by the water
(Bjorneberg 2013).
Furrows method provides better on-farm water management flexibility under
many surface irrigation conditions. This method provides the irrigator opportunity
to manage irrigation water toward higher efficiencies as irrigation field conditions
changes throughout a season. However, the furrow method does not enjoy much
higher application efficiencies than borders and basins. Additional disadvantages
with furrow irrigation method may include:
(1) Salt accumulation problems are encountered between furrows.
(2) Increased level of tail water losses.
(3) Movement of farm equipments across the furrows is tedious.
(4) Added expense and time to make extra tillage practice (furrow construction).
(5) Increase in the erosive potential of the flow.
(6) Higher labour and operational demand.
(7) Generally, furrow systems are more difficult to automate, particularly about
regulating an equal discharge in each furrow (NRCS 2012)
Ranging from 1/5 to 1/2 of the field, this method helps in reducing the evaporation
losses and achieving high water-application efficiency. Water is supplied from the
field channel (or a supply ditch) to the furrows either through small cut made in the
banks of the field channels or through small portable siphons sometimes concrete
161
16.2.2.1 Design Criteria
The following are the general design criteria for the strips:
(1) Width
(2) Slope
(3) Length
(4) Location of levees and strips
(5) Computation of time to cover a strip (Arora 2014).
16.2.3 Furrow Irrigation Method
In furrow irrigation method water is applied to the field to be irrigated along a series of
long narrow path called furrows. This is done to avoid spreading the whole land with
water for minimization of water. In this type of surface irrigation, the furrows are dug
at intervals and at right-angles to the field channels or laterals. Water application is
dependent on the length of the furrows, water management factors and soil properties
in furrow type of irrigation. Water is being flowed into the furrows for 12–24 h during
irrigation exercise, and it can be longer or shorter depending on the aforementioned
factors. It is worth noting that, water is not spread over the whole irrigated field.
The water flowing in the furrows infiltrates the soil and spreads laterally and reaches
the roots of the plants between the furrows. As discussed earlier in furrow type
of irrigation only some portion of the land is wetted (i.e. in between the laterals),
whereas in basin and border methods the entire field is wetted directly by the water
(Bjorneberg 2013).
Furrows method provides better on-farm water management flexibility under
many surface irrigation conditions. This method provides the irrigator opportunity
to manage irrigation water toward higher efficiencies as irrigation field conditions
changes throughout a season. However, the furrow method does not enjoy much
higher application efficiencies than borders and basins. Additional disadvantages
with furrow irrigation method may include:
(1) Salt accumulation problems are encountered between furrows.
(2) Increased level of tail water losses.
(3) Movement of farm equipments across the furrows is tedious.
(4) Added expense and time to make extra tillage practice (furrow construction).
(5) Increase in the erosive potential of the flow.
(6) Higher labour and operational demand.
(7) Generally, furrow systems are more difficult to automate, particularly about
regulating an equal discharge in each furrow (NRCS 2012)
Ranging from 1/5 to 1/2 of the field, this method helps in reducing the evaporation
losses and achieving high water-application efficiency. Water is supplied from the
field channel (or a supply ditch) to the furrows either through small cut made in the
banks of the field channels or through small portable siphons sometimes concrete