For traveling sprinkler irrigation systems use table 2 for towpath spacing. 2 - Towpath Spacing for Traveling Sprinkler Systems (expressed as percent of wetted diameter*). Average Ring Tapered Wind Velocity Nozzle Nozzle (mph) 0 to 1 80 80 1 to 6 70 75 6 to 10 60 65 > 10 ** 50 55 * Because the distribution pattern of traveling systems is seriously affected by wind, operation in winds greater than 10 mph is not recommended. Land Slope. Field slope for a LEPA system shall not exceed 1percent on more than 50 percent of the field with a maximum slope of 3 percent. Field slopes for other center pivot or linear move systems with sprinklers on drops shall not exceed 3 percent on more than 50 percent of the field for fine and moderately fine soils, as described in the National Engineering Handbook, Part 652, National Irrigation Guide, Table 2-5. On coarser soils, analyze how runoff will be controlled on center pivot or linear move systems installed on slopes greater than 5 percent. Base the analysis on field observations or approved runoff models (e.g. CP® Nozzle). Regardless of soil texture, field slopes shall not exceed 3 percent on more than 50 percent of the field or center pivot or linear move systems that operate sprinklers within the crop canopy for 50 percent or more of the growing season, Maximum field slopes for center pivot or linear move systems shall not exceed manufacturer’s slope limitations based on pivot profile, span length, pipe diameter, and tire size. Pressure Regulators. In absence of manufacturer’s recommendations for pressure regulator operation, ensure line pressure upstream of all regulators is at least 5 psi above rated regulator pressure. Linear Move/Periodic Move Lateral Lines. Unless pressure reducers or regulators are installed at each outlet, or other pressure compensating or flow control devices are used, lateral lines shall be designed so that pressure variation along the lateral line does not exceed 20 percent (or 10% of design flow) of average design operating pressure. Risers. Except for under-tree operation, place the riser pipes used on lateral lines high enough to prevent interference with the distribution pattern when irrigating the tallest crop. Riser heights shall not be less than shown in table 3.
For traveling sprinkler irrigation systems use table 2 for towpath spacing. 2 - Towpath Spacing for Traveling Sprinkler Systems (expressed as percent of wetted diameter*). Average Wind Velocity (mph) Ring Nozzle Tapered Nozzle 0 to 1 80 80 1 to 6 70 75 6 to 10 60 65 > 10 ** 50 55 * Because the distribution pattern of traveling systems is seriously affected by wind, operation in winds greater than 10 mph is not recommended. Land Slope. Field slope for a LEPA system shall not exceed 1percent on more than 50 percent of the field with a maximum slope of 3 percent. Field slopes for other center pivot or linear move systems with sprinklers on drops shall not exceed 3 percent on more than 50 percent of the field for fine and moderately fine soils, as described in the National Engineering Handbook, Part 652, National Irrigation Guide, Table 2-5. On coarser soils, analyze how runoff will be controlled on center pivot or linear move systems installed on slopes greater than 5 percent. Base the analysis on field observations or approved runoff models (e.g. CP® Nozzle). Regardless of soil texture, field slopes shall not exceed 3 percent on more than 50 percent of the field or center pivot or linear move systems that operate sprinklers within the crop canopy for 50 percent or more of the growing season, Maximum field slopes for center pivot or linear move systems shall not exceed manufacturer’s slope limitations based on pivot profile, span length, pipe diameter, and tire size. Pressure Regulators. In absence of manufacturer’s recommendations for pressure regulator operation, ensure line pressure upstream of all regulators is at least 5 psi above rated regulator pressure. Linear Move/Periodic Move Lateral Lines. Unless pressure reducers or regulators are installed at each outlet, or other pressure compensating or flow control devices are used, lateral lines shall be designed so that pressure variation along the lateral line does not exceed 20 percent (or 10% of design flow) of average design operating pressure. Risers. Except for under-tree operation, place the riser pipes used on lateral lines high enough to prevent interference with the distribution pattern when irrigating the tallest crop. Riser heights shall not be less than shown in table 3.
SprinklerSystem_442_Draft_Dec2015.docx