Use of a chemical tracer to evaluate water movement through two automatic watering rack manifolds during flushing

A sodium fluorescein solution was introduced into an upfeed serpentine and a horizontal automatic watering rack manifold. Water samples were collected from nine drinking valves on each manifold prior to and after flushing at 12 pounds per square inch water pressure for 15 seconds, one minute, and five minutes. The water samples were assayed for fluorescein and it was found that the chemical was effectively removed by flushing from the upfeed serpentine manifold, while significant levels of fluorescein remained in the horizontal manifold even after five minutes flushing.