Use a snake or hydraulic jet to try and remove the clog. — Once you have successfully determined that the pipe is not broken, and that the line is indeed clogged, you can use a metal snake to try and remove it.
Remove the air you need to manually open two or more of the circuit valves at once. Run the water for a while in order to force all of the air out. Make sure to close the valves one at a time. A pressure surge can be caused if you close them at the same time and the surge could damage your irrigation system.
Check all of the valves to make sure they are fully open, especially the main system shut-off valve and the valves on your backflow preventer. A partially closed valve will reduce the water to the sprinklers, causing them to not fully pop up. This could affect some or all of your zones.
Dig a hole around the affected sprinkler head and make it wide enough to prevent dirt from entering the lines. Grasp the head and turn it clockwise until it comes off before turning on the water and rinsing the head. If the system shows signs of clogging, it may be time to call an irrigation expert.
You can typically tell when you're dealing with a clogged sprinkler head when water either isn't coming out or when the water pressure has decreased substantially (trust us, you'll notice).
Flush the main and secondary pipes with clean water. Apply the chlorine solution: ready when the last dripper has pH >10. Leave the system filled for 24 hours, do not irrigate. Flush after the chlorine solution: rinse the pipes and mixing tanks with clean water, irrigate for some time.
Ideal pressures are in the range of 40 to 80 pounds per square inch (psi) for the air compressor with 80 psi being the maximum for rigid PVC pipe and 50 psi for polyethylene pipe (flexible black pipe). Set the pressure regulator on the air compressor accordingly.
While these sounds can be scary and seem like serious issues, the cause is usually quite benign. Most often, a loud sound coming from your pipes is caused by trapped air. By turning off your main water supply and running all faucets for 10-15 minutes, you force any trapped air through your water pipes.
Drip irrigation systems can commonly become clogged by mineral or bacterial buildup resembling salt or sludge, but you can clean them by flushing the system with water. To flush the lines with water, plug all of the emitters, which are the holes in the tubing, so the water can't escape through them.
Clogged sprinkler heads: You may have a clogged sprinkler head if the head doesn't rise and there is no water. Dirt, sand and other debris build up in the sprinkler head filters. To clean a filter: Turn off your water, lift the pop-up riser, remove the nozzle and the filter, clean the filter and return to the nozzle.
A sprinkler system blowout is the most expensive drainage method, and it typically costs $85 – $235, depending on the number of watering zones and other cost factors. If the sprinkler pro suggests you get a blowout, you should take that suggestion to avoid costly repairs.
You can snake the line and use a camera to determine if debris has become clogged, and if so, where. You can also walk the irrigation line and look for puddles of water or depressions in the ground, which might indicate that the pipe has in fact broken due to the pressure surrounding the clog.
Turn off your water at the dedicated Sprinkler Line Shutoff (A) in your basement / crawlspace. Open the 2 Petcock's (F) with a flat head screwdriver so that the screw head runs a 45 degree angle. Open the Inside Drain (B) to drain your system. Make sure to have a bucket available for water drainage.
Flushing with Vinegar and Baking Soda
One effective and environmentally friendly method to clean water pipes involves using a mixture of vinegar and baking soda.
You Hear a Gurgling Sound When Water is Flowing
The most prominent sign that your pipes are clogged is a reduced flow rate. Whether it is your shower pipe, faucet, or drain if you see that the water does not flow as fast as it should then you're most probably dealing with some sort of blockage in the pipes.