Subsurface drip irrigation (SDI) is a one-step-up irrigation method and a more sustainable alternative to conventional surface drip irrigation. Nowadays, a lot of gardeners and farmers are looking for an efficient irrigation method due to heat spells, days of drought, and water-wise gardens. SDI uses water more effectively and reduces evaporation because it delivers water directly to the plant's roots under the soil. This irrigation method is appropriate for all types of crops and works well in windy and arid locations. In this blog post, we will discuss everything you need to know about this versatile irrigation method.
What is Subsurface Drip Irrigation
Subsurface drip irrigation is a modern and sustainable irrigation system that applies water directly to crops' root zones using buried drip lines or drip tape. In this irrigation method, the drip tubes are buried under the soil surface rather than on the ground. Wetting occurs around the drip tube, and water flows in all directions.
As the water is delivered below the soil surface, the impacts of surface infiltration, such as water loss due to evaporation, crusting, and surface runoff, are eliminated. With a well-maintained and appropriate subsurface drip irrigation system, water application is uniform and efficient.
There are two forms of sub-surface drip irrigation.
Shallow Burial Subsurface Drip Irrigation: In this form of SDI, the drip line or drip tape is buried a few centimeters beneath the soil surface. It allows growers to prevent the thin tubing from being affected by wind while achieving the sustainable benefits of irrigation. This drip line is supposed to be removed after the season. The shallow burial method is commonly used with single-season vegetables, melons, and strawberries.
Deep Burial Subsurface Drip Irrigation: This method refers to the deep burial of the drip line at least 10 centimeters (4") beneath the surface. The goal of this SDI method is to use the same drip line for several years. This irrigation method is used to irrigate numerous crops, including corn, cane, vineyards, cotton, orchards, tomatoes, and alfalfa.
Advantages of Subsurface Drip Irrigation
Here are the long-term benefits you will experience using the Subsurface drip irrigation method.
Switching from traditional sprinkler or surface irrigation to subsurface drip irrigation can result in significant water savings. When water is applied underground, it eliminates surface evaporation. SDI saves water by preventing evaporation and water runoff.
Efficient Water Delivery
SDI can be more efficient than any other irrigation system if installed and handled correctly. SDI offers substantial control over the amount of water application and uses high-frequency irrigation. Since drip tubing is placed in the soil between each crop row, this system only wets a small portion of the soil. Small and controlled amounts of water help avoid water logging and provide an optimal environment for crop root growth. This method reduces the need for net irrigation because it leaves space in the soil for storing rainwater.
Since the water is applied directly to plants' roots, no water goes between rows of plants, and the interrow soil remains dry. A dry soil surface means less weed germination and limited growth of shallow-rooted weeds. It also saves herbicide costs required to get rid of weeds.
Increase Potential Yield
You can automate the SDI system for frequent water applications. Fertilizers, fungicides, and herbicides are crucial to growing healthy and successful crops. SDI can be used for chemigation applications with irrigation water. These systems can apply a controlled amount of water and other inputs once a day or multiple times a day. You can adjust the water and nutrients application according to crop needs, resulting in higher yields and lower nutrient loss.
Irrigate Odd Shaped Fields
One of the best benefits of using a subsurface drip irrigation system is that you can install it in odd-shaped fields and maximize each hectare. The SDI system adapts well to fields of any shape and size. When installing in rolling terrain, it is recommended to use pressure-compensating emitters for uniformity.
Easy Access to the Field and Harvest
When drip lines are buried, and there are no irrigation pipes on the surface, field access and harvest are easy. Additionally, you can irrigate crops like sugarcane and alfalfa until harvest time without the risk of bogging.
Key Components of Subsurface Drip Irrigation
The key components of the system include:
- Main and sub-main lines
- Water Source
- Lateral drip lines
Best Products to Use in SDI System
The product selection is the most critical step that will save you time and money in the long run while ensuring your SDI system works effectively. Here are the best products to use:
- Heavy wall Netafim tubing
- 1/2 emitter tubing with pre-built pressure-compensating emitters.
- Air bleed valves: best to use with a drip irrigation system in uneven areas.
DripWorks offers an extensive selection of subsurface drip irrigation products and quality system accessories that are built to meet your specific crop and soil needs. Our top-quality irrigation products are designed to work together to ensure a successful SDI system.
Installation of Subsurface Drip Irrigation System
A subsurface drip irrigation system installation can require a lot of work, but it is easy to install even if you have little irrigation experience. You can DIY or call the specialist to install the system.
- Clear out debris from your yard or lawn.
- Install the mainline that carries the main flow of water.
- Next, install drip lines around 100 mm beneath the soil surface.
- Install the flush valve at the end of the mainline to flush out any obstructions.
- Make sure to install an air release valve at the highest point in the yard. This valve is designed to release any trapped air in the pipes.
- Test the system for a few minutes to ensure there are no leaks before covering it with topsoil.
Remember that proper design and installation of the system are essential to the system's effectiveness. There are lots of important steps that DIY homeowners may overlook, such as measuring the diameter of the dripline, proper procedures, system layout, and distance between emitters. So, make sure to follow the right installation procedure or seek help from irrigation specialists.
Maintenance of Subsurface Drip Irrigation System
Subsurface drip irrigation is a highly efficient and sustainable irrigation method that has been widely used to produce high-value crops. However, the performance and lifespan of any irrigation system depend on how it is designed, installed, and maintained. The SDI system should be regularly inspected or automatically controlled. All the mechanical components of the system, such as valves, filters, and pumps, should be checked and cleaned regularly.
Additionally, rodents like to chew the pipes, so take precautionary measures. SDI systems should be designed with the ability to flush all mainlines, headers, sub-mains, and laterals. It is crucial to flush the lines once every two weeks during the growing season. Finally, it is imperative to winterize the drip irrigation system at the end of the season.