Setting the pressure for your vineyard’s irrigation system will depend on several factors including the type of irrigation system used, topography, and water requirements. One of the best watering and irrigation tactics for vineyards has been to use drip irrigation. It is important to note that drip irrigation methods should be installed so that they can uniformly apply water. Drip irrigation will use a wire for support and either in-line or punch-in emitters to distribute the water. Whether you choose to install a drip irrigation system, or prefer to use another watering method, it is important that you maintain the correct pressure.
Pressure Control Considerations
The proper pressure setting for the irrigation equipment that you choose will vary somewhat by the manufacturer. Always consult the manufacturer’s design information when making this decision.
- Pressure compensating vs. non-pressure compensating emitters—Since most vineyards are grown in mountainous regions or on other undulating terrain, pressure compensating emitters are a must. Most pressure compensating emitters will compensate between 25 to 50 psi. Pressure compensating emitters allow for the change in pressure caused by change in elevation and friction loss along the lateral drip tubing.
- Pressure control valves vs. pre-set pressure regulators – Pressure control valves allow for the adjustment of the outgoing pressure and they can also serve as an on-off valve as well. Pre-set pressure regulators usually do not allow for any pressure adjustment and usually have a limited flow range. Pre-set regulators can also be inaccurate at the low or high end of their flow range.
- Set pressure for system uniformity – The primary goal for proper pressure regulation is system uniformity. The objective is for a plant at the end of a row to receive the same amount of water as the plant at the beginning of the row. Uniformities of 90 to 95% are not uncommon when the system is designed and installed properly.
Trouble Shooting Pressure Issues
If maintaining the proper pressure continues to be a problem, here are some things to consider.
- Check the manufacturer’s design guide to determine the optimum pressure setting.
- Check for clogged emitters. Clogged emitters lower the system flow rate which will cause the system pressure to increase.
- Check for clogged filter system. A filter that is not cleaned or backwashing properly can cause low system pressure.
- Check for leaks. Large leaks or a lot of small leaks can cause low system pressure.
To learn more about how to properly install and pressurize your vineyard’s irrigation system, we invite you to contact us at W.P. Law, Inc. Our team of experts is ready to help you choose the correct system for your specific vineyard needs.