Page 56 - Azerbaijan State University of Economics

THE JOURNAL OF ECONOMIC SCIENCES: THEORY AND PRACTICE

Description of Irrigation Systems
Furrow and surge flow systems are the two surface irrigation

systems considered in this analysis. Each system is assumed to irrigate
160 acres. Furrow is assumed to have an application efficiency of 60

percent and a discharge pressure of 10 pounds per square inch (psi).
This low efficiency is attributed to the non-uniform distribution,

evaporation from the wetted area and deep percolation of water. Surge
flow has an application efficiency of 75 percent with a discharge

pressure of 10 psi. The major difference between furrow and surge flow

is the utilization of a surge valve. The surge value enhances furrow
irrigation effectiveness by intermittently applying water and taking

advantage of the reduced infiltration parameter associated with soil

surface tensions with time.
Three center pivot systems, MESA, LESA, and LEPA are

analyzed. Each center pivot is assumed to cover 125 acres. MESA is
defined as having 145 drops mounted on top of the center pivot’s main

line. The sprinkler heads are positioned approximately midway between
the mainline and ground level. Water is applied over the crop canopy

with MESA resulting in greater water loss due to evaporation and wind

drift. MESA has an efficiency rate of 78 percent with a discharge
pressure of 25 psi. The application efficiency of MESA is relatively low

compared to LESA and LEPA.
LESA is the predominant system within the Panhandle Water

Planning Region (New, 2009) and has an average application efficiency
of 88 percent with a lower operating pressure of 15 psi. The 261 drops

are positioned 12 to 18 inches above ground level. LEPA has an

application efficiency of 95 percent with an operating pressure of 15 psi.

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