Surface or flood irrigation is the least efficient manner of irrigation. When a field is flooded, more water than is needed by the plant is applied to the field and water evaporates, seeps into the ground and percolates down to the groundwater, where it can be out of reach of the plant's roots.
Furrow or flood irrigation is widely used in many parts of the world, including the US, but is the least efficient, losing about 50 percent of water applied. This loss can be reduced by leveling fields, practicing surge flooding and capturing and reusing runoff.
Flood irrigation is not the most efficient irrigation method, but it is cheap and low-tech. On the one hand, less water is lost to evaporation than in spray irrigation, but on the other hand, more water can be lost from runoff at the edges of the fields.
Poorly designed irrigation systems apply water nonuniformly and will result in waste of water and chemicals applied with the water. Nonuniform irrigation distribution will result in over- and/or under-irrigation of parts of fields.
Globally, agriculture uses 70% of the planet's freshwater resources and 95% of the world's farmers use flood irrigation. Unfortunately, flood irrigation is the most inefficient of all irrigation systems, including center pivot and drip irrigation systems. Flood irrigation wastes upwards of 50% of the water used.
Drip System
Drip irrigation is the most water-efficient way to irrigate many different plantings. It is an ideal way to water in clay soils because the water is applied slowly, allowing the soil to absorb the water and avoid runoff. Drip devices use a fraction of the water that overhead spray devices use.
Small tubing often becomes clogged from hard water and although new designs include filters and self-flushing emitters, they are costly. The tubing/system is unsightly. And because it's unsightly, tubing is often covered by mulch or plant foliage, making it difficult to monitor the effectiveness of the system.
The expansion and intensification of agriculture made possible by irrigation has the potential for causing: increased erosion; pollution of surface water and groundwater from agricultural biocides; deterioration of water quality; increased nutrient levels in the irrigation and drainage water resulting in algal blooms, ...
The best sustainable irrigation technique by far is drip irrigation. Drip irrigation is a system of pumps and tubes. The tubes are either suspended above the soil or planted alongside the roots of the plant.
Drip irrigation is the most expensive irrigation system to set up and manage, requiring significant amounts of labor for installation, removal, and seasonal maintenance.
Sprinkler ir- rigation and microirrigation use pipes to distribute water through the field. Surface irrigation is generally thought to cause more erosion than sprinkler irrigation; however, erosion can occur any time water flows over soil.
Certain crops are more susceptible to bacteria or fungus if they stay wet for too long. And, Nicolai said, he knows some farmers who aren't as comfortable with complicated machinery running while they're asleep in their bed.
Sprinklers cover a much larger surface area than drip irrigation does, which can be particularly beneficial to someone with a larger property.
Research consistently shows yield and quality of produce improves when a buried drip system is used. Normal life expectancy of a system is considered to be 12 to 15 years.
Water Conservation: While underground systems can provide efficient water distribution, they may be prone to water loss due to evaporation or wind drift. Sprinkler heads, although adjustable, may overspray or result in uneven water distribution, leading to water waste.
Manual Watering
All you need for manual watering is a hose and time. Just grab the hose and water it yourself. Manual watering is perhaps the most affordable of all the sprinkler system alternatives, but it also is the most time-consuming.
This proves that sprinklers reduce pollution and water usage, as it is much better to have a sprinkler system present when a fire breaks out as opposed to letting the fire department spray gallons of water onto the building. Fires release carbon emissions at an alarming rate.
Drip irrigation systems have always been exempt from hosepipe bans and are likely to continue to be exempt. Modern drip irrigation systems like our WaterMate are extremely efficient in the distribution of water and on average, saves between 70-90% of water compared with hand watering.
Disadvantages of the drip irrigation system are given below: High initial investment requirements. Regular capital requirement for replacement of drip irrigation equipment. Drip irrigation emitters are vulnerable to clogging and dysfunction.
Drip irrigation is highly effective at supplying one to four gallons of water per hour directly to the soil. The advantage of drip irrigation over sprinklers is that there is little water loss due to evaporation or runoff.
A closer look reveals that while drip has much higher yields and produces less ag waste, it is more expensive. That drip uses less water is controversial is some circles, since flood irrigation is thought to “recharge the aquifer”.