Navigation Predictive Analysis Technique (NAVPAT) Pilot U.S. Army Corps of Engineers Louisville District. 1995. Navigation Predictive Analysis Technique (NAVPAT) Pilot Application for Pool 13, Upper Mississippi River. National Biological Service, Environmental Management Technical Center, Onalaska, Wisconsin, September 1995. LTRMP 95-S001. 54 pp. + Appendixes A-D. (NTIS #PB96-147731) ABSTRACT The U.S. Army Corps of Engineers, Louisville District, conducted a pilot application of Navigation Predictive Analysis Technique (NAVPAT), a model for assessing incremental environmental effects of commercial navigation traffic on main channel Upper Mississippi River Pool 13. Upper Mississippi River Pool 13 was divided into units of similar habitat. Seasonal changes in stage and discharge were included. River reaches were described, including analysis of banks, mapping of depths and substrate, and measurement of water velocity. The needed economic data were developed from 1989 actual usage of Lock 13 (44 million tons). Two traffic scenarios, 44 and 88 million tons, were developed for the Pool 13 application. Each tow was a unique vessel and reflected seasonal traffic patterns. Thirteen species life stages of fishes were used in the analysis. The species life-stage models represent other species that share similar life requisites. The NAVPAT biological models are similar to those in Habitat Evaluation Procedures (HEP) or Instream Flow Incremental Methodology (IFIM) models. The results of the pilot application of NAVPAT indicate that seven species life stages could be impacted by doubling existing commercial navigation traffic. Substantial decreases in NAVPAT units would occur with an increase of commercial navigation traffic from 44 to 88 million tons for four species life stages, with lesser decreases projected for three species life stages. The remaining six life stages reflect little loss of NAVPAT units. KEYWORDS Bathymetric mapping, biological models, commercial navigation traffic, cross-section geometry, habitat units, Long-Term Resource Monitoring Program, navigation traffic pattern, Navigation Predictive Analysis Technique (NAVPAT), physical forces, species life stages, suitability index