Irrigation water surface is the mode of administration of the oldest and most commonly used. How the water in this way is often called the flooding irrigation, because in this way the irrigation water given in a particular location, is allowed to flow freely on the surface of the land, and then the water will fill the root zone of plants. It is different when compared to bulk irrigation system where water is distributed to the land through pressurized pipes and drip irrigation systems, where water is supplied through sprinklers or dropper to the surface.
By using surface irrigation system, water is supplied directly through the ground surface of a duct or pipe that has a high water level is higher than the elevation of the land to be irrigated, usually about 10-15 cm. Irrigation water will flow at ground level from the base to the tip of land and seep into the soil drench the root zone of plants. Important requirement to obtain an efficient surface irrigation system is planning water distribution system to control the flow of irrigation water with good land leveling, so that the water spread uniformly throughout the plot.
Figure 1. Surface Irrigation Systems
In principle, the design of surface irrigation system was designed some parameters so we get a chance infiltrate relatively uniform from the base to the tip of the land. Generally at the base, the water will seep more water than the end of the plot of land, so we get a small water-use efficiency. Procedures for implementation of irrigation in surface irrigation is by using a debit large enough, then the flow will reach the end as quickly as possible, and seep into the ground evenly.
After or before it reaches the end, the inflow can be reduced debits until the desired amount of irrigation water has been absorbed. Supply water flow is stopped and the recession will happen to the land along the irrigation process is completed. System surface irrigation has been widespread and can be classified into several types, namely (1) irrigation basin (basin irrigation), (2) irrigation border (border irrigation), (3) irrigation furrow (furrow irrigation), and (4) inundation free ,
The differences between the various types of irrigation above often be subjective. Flooding irrigation is a catch-all category for situations where the water is only allowed to flow into the area without any attempt to regulate the provision of airnnya or uniformity. And because no attempt was made to set up an application or uniformity. If the irrigation system to control the flooding, the flooding irrigation systems can be categorized into irrigation border or basin and furrow irrigation.