Converting a standard sprinkler head into a connection point for a drip irrigation system is a common and effective do-it-yourself project. This process transitions the high-volume, high-pressure output from the existing underground piping to a low-volume, low-pressure source suitable for drip lines. Homeowners can utilize their existing irrigation infrastructure, including valves and timers, to feed a more efficient watering method. This conversion allows for the precise, measured delivery of water directly to plants, improving upon the wide-area coverage of traditional pop-up heads.
Why Convert Sprinklers to Drip?
The primary motivation for converting from overhead sprinklers to a drip system is superior water conservation and improved plant health. Standard sprinkler heads distribute water over a wide area, leading to substantial loss through misting, wind drift, and surface evaporation before the water reaches the root zone. Drip irrigation delivers water slowly and directly to the base of the plant, minimizing these losses and achieving a watering efficiency that can be up to 70% better than conventional methods.
The targeted delivery of water helps plants thrive by providing consistent moisture where they need it most, preventing the stress caused by cycles of soaking and drying. Furthermore, overhead watering wets the foliage, creating an ideal environment for fungal diseases and mildew. Because drip systems keep the plant canopy dry and only wet the soil immediately around the plant, they also suppress weed growth in the surrounding, unwatered areas.
Necessary Materials and Preparation
Before beginning the conversion, locate and shut off the main water supply to the irrigation system to prevent unexpected water flow. The core of the conversion requires a threaded conversion adapter, typically featuring a half-inch Female Pipe Thread (FPT) inlet. This screws onto the existing half-inch Male Pipe Thread (MPT) sprinkler riser, creating a secure connection point.
A specialized drip conversion kit includes components necessary for a functioning drip system:
- A pressure regulator to drop the high incoming pressure.
- A filter to prevent sediment from clogging the drip emitters.
- Main drip line tubing, often half-inch poly tubing, to run from the adapter.
- Teflon tape for ensuring a watertight seal on the threads.
- Standard tools like a small shovel or trowel for excavation and a pipe wrench for removing the old head.
The Physical Conversion Steps
The initial step is to locate the existing sprinkler head that will serve as the water source and carefully excavate the soil around it. You only need to expose the base of the head and the threaded riser pipe it connects to, usually by digging down a few inches. Once exposed, the existing sprinkler head or riser extension must be unscrewed and removed from the underground pipe. Prevent dirt and debris from falling into the open pipe, which could contaminate the system.
Next, prepare the threads for the new component. Apply two to three wraps of Teflon tape clockwise around the male threads of the exposed riser pipe. This tape acts as a sealant and lubricates the threads, ensuring a complete, leak-free connection. Screw the new drip conversion adapter onto the prepared threads of the riser pipe. Hand-tighten the adapter, then secure it with a pipe wrench, taking care not to overtighten and crack the plastic fitting.
Managing Water Flow and Pressure
The final step involves adapting the system’s hydraulic characteristics to the needs of drip irrigation. Standard sprinkler systems operate at high pressures, typically between 40 and 60 pounds per square inch (PSI), which would cause drip emitters to blow out and fittings to disconnect. Therefore, a pressure regulator must be installed immediately after the conversion adapter to reduce the working pressure to the optimal range for drip components, usually 15 to 25 PSI.
This pressure reduction is necessary to ensure uniform water delivery and to protect the system’s integrity. Following the pressure regulator, a filter, such as a screen or disc filter, is required to remove fine particulate matter from the water. Without a filter, the very small orifices of the drip emitters would quickly become clogged, leading to system failure. These two components are typically integrated directly into the conversion unit or installed in sequence before the main drip line tubing is connected.