Converting an existing sprinkler zone to a drip irrigation system is an effective way to improve watering efficiency and conserve water. Drip systems deliver water slowly and directly to the plant root zone, which significantly reduces the water loss that occurs through evaporation and wind drift with traditional spray heads. This conversion allows you to utilize the existing underground piping, valve, and timer infrastructure, saving considerable effort compared to installing a new system from the main water line. The process involves replacing a sprinkler head with a dedicated assembly that manages the water flow and pressure for the drip components.
Essential Components for Conversion
The conversion process requires specific components to transition from a high-pressure sprinkler line to a low-pressure drip system. You will need a conversion adapter, a fitting that screws onto the sprinkler riser and transitions the connection to a hose thread. The system relies on main supply tubing, typically flexible polyethylene in 1/2-inch or 3/4-inch diameters, to carry water across the planting area. Smaller, 1/4-inch micro-tubing is used to branch off the main line and reach individual plants. Emitters are the final components, releasing water at a controlled rate, and can include drippers, micro-sprayers, or bubblers.
Connecting the Conversion Kit to the Sprinkler Riser
The first step is selecting the appropriate sprinkler head in the zone to be converted. After turning off the water supply, unscrew and remove the existing sprinkler head from the riser. You may need to dig around the head to fully expose the riser connection point, which is typically a 1/2-inch or 3/4-inch male pipe thread. Briefly turn on the water after removal to flush any dirt or debris that may have fallen into the riser. The main conversion adapter, often an elbow or specialized manifold, is then threaded securely onto the exposed riser.
Installing Pressure Regulation and Filtration
Drip irrigation systems operate at a significantly lower pressure than traditional sprinklers, requiring water pressure to be reduced to between 15 and 30 PSI. High-pressure water will cause fittings to fail and emitters to spray rather than drip, necessitating a pressure regulator. Filtration is mandatory because the small openings in drip emitters are highly susceptible to clogging from debris and sediment. A filter with a 150- to 200-mesh screen is recommended to catch particles before they enter the system. The standard installation sequence is to connect the conversion adapter to the filter, followed by the pressure regulator, and finally the main drip tubing adapter.
Running and Configuring the Drip Lines
With the head assembly in place, unroll and lay out the main supply tubing through the garden, following the path to the plants. Leave the polyethylene tubing in the sun for a short time to make the material more flexible. Secure the tubing to the ground using landscape stakes every few feet, avoiding sharp bends that could restrict water flow.
Holes are then punched into the main tubing near the plants using a specialized punch tool. Small sections of 1/4-inch micro-tubing are connected to these holes with barbed fittings, leading to the plant’s root zone. The appropriate emitter, chosen based on the plant’s water needs, is attached to the end of the micro-tubing and placed near the base of the plant. Finally, seal the end of the main supply tubing with a cap or a figure-eight clamp to maintain system pressure.