The Phosphorus Runoff Risk Evaluator (PRRE) is a joint project of the United States Department of Agriculture - Natural Resources Conservation Service (NRCS) and the University of Hawaii at Manoa. PRRE is the Hawaii implementation of the concepts behind the Phosphorus Index (PI) of NRCS. The Hawaii version was developed because the soils, climate, and crops are different from those on the continental USA and may dramatically affect the amount of phosphorus conveyed to the receiving water bodies. PRRE is an effort to identify sites that may contribute excessive amounts of phosphorus to its receiving water bodies. It also suggests management measures to reduce or eliminate phosphorus contamination of streams, estuaries, and other water bodies that receive runoff from the tropical agricultural and natural lands.
Save file PREE_1.01.zip to a temporary folder on your hard disk. Unzip the executable file it contains, run it and follow the on-screen instructions.
Note: System requirements to run the PRRE program are–
Any IBM-compatible machine with at least a 400 Mhz processor.
Microsoft Windows 2000/XP
Microsoft Access 2002 installed
At least 128 megabytes of memory
At least 100 megabytes of hard drive storage space
Before running the PRRE software, please have the following data or analyses ready: 1. UH-ADSC or other soil analysis for phosphorus, together with the analytical method (i.e. Truog in Hawaii if soil pH is less than 7, Olsen if the soil pH is equal or greater than 7); 2. Run RUSLE to obtain soil loss for "existing" and "planned" condition, unless active gullies are present. 3. Obtain the calculated path length, in feet, between the field and the associated waterbody or closed basin. This can be obtained from a DRG map with ArcView/Toolkit or measured from a USGS quad. 4. Click File/Print Data Form to print a copy of minimum data set.