Spray Fields (IMAGE) Penn State Caption A spray field at the Living Filter. The University started spray irrigating its treated wastewater here in the 1960s as an alternative to discharging effluent into Spring Creek, a wild trout stream of considerable repute. This study suggests there may be some environmental tradeoffs. Credit Penn State Usage Restrictions Non commercial use only License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.