The objective of this project is to evaluate the impact of spring applied swine manure for soybean crop on sub-surface drainage water quality from non-replicated micro-watersheds. To evaluate this impact, sub-surface flow from tile outlets in two micro-watersheds planted to soybeans was monitored for nutrients (nitrogen and ortho-phosphate). Two additional micro-watersheds, planted to corn and with no manure application, were also monitored during this time period. Tile outlets from the micro-watersheds were instrumented with ISCO flow samplers and flow meters. This has been done to record flow volumes being discharged from the micro-watersheds. Water samples were collected to determine nitrate-nitrogen and ortho-phosphate concentrations in tile flow. Manure was applied to one of the paired micro-watersheds in spring of 2012 before it was planted to soybeans. Both micro-watersheds were monitored and data was recorded from April 26 to November 30, 2012. Analysis of data shows that the flow weighted nitrate-N (NO3-N) concentrations were higher for the micro-watershed A for the post-manure application time period in comparison with the pre-manure application time period. Flow weighted nitrate-N (NO3-N) concentrations were comparable for the micro-watershed A where manure was applied with micro-watershed B where no manure was applied, with both watersheds planted to soybeans. When micro-watershed C and D (both planted to corn with no manure application) were compared, micro-watershed D had higher flow weighted nitrate-N concentration in comparison to micro-watershed C. The flow weighted ortho phosphate-P (PO4-P) concentrations were slightly higher for the micro-watershed A where manure was applied in comparison to all other micro-watersheds. Very few water samples for micro-watersheds B, C, and D showed ortho-phosphate concentrations above the non-detect limit. As 2012 was a drought year, the limited data available from this study should be carefully evaluated and used. The project was carried out in collaboration with Iowa Select Farms. Funding, wholly or in part, was provided by The National Pork Board on behalf of the Iowa Pork Producers Association.