TCEQ IRRIGATION LICENSE STUDY GUIDE

BPA requirements for fertilizer injection system - Reduced Pressure Principle Assembly (RPPA) (RPZ) is required when fertilizer injection are being used. Causes backsiphonage? - Caused by a negative or Sub-atmospheric pressure. Example-City departments are using fire hydrant or there's a city main line break, or someone sucking liquid from a glass using a straw. Causes of leaking check valve - Debris-can enter the valve. (Can use Y strainer to provide a solution.) characteristics of flow vs pressure for given pipe size - as flow increases pressure decreases velocity increases characteristics of looped irrigation main lines - 1/2 flow gym by 1/2 pipe low pressure, loss downsize pipe, both at the same time. Characteristics of water - non compress-able, potable, non potable Common units of measure for flow rate in landscape irrigation - (GPM, gallons per minute) (GPH,Gallons per hour), (IPH, Inches per hour) Conversion of psi to feet (head) of water - 1' = .433 PSI 2.31'= 1 PSI