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Two green roofs were constructed and monitored in eastern North Carolinas Neuse River Basin. Due to recent regulations to minimize the amount of nitrogen and phosphorus in storm water runoff, storm water BMPs have been used to reduce nutrient loadings. In ultra-urban areas where typical BMPs are not optimal, due to large surface area requirements, the green roof is a new option. The hydrologic and water quality performance of two different green roofs were investigated. Each green roof retained a significant proportion of the rainfall, peak outflows were significantly reduced from the green roofs, and each green roof had substantial delays in runoff. Both concentrations and amounts of total nitrogen and total phosphorus increased from rainfall to green roof outflow and from the control roof outflow to green roof outflow. It was determined that the soil media, composed of 15% compost, was leaching nitrogen and phosphorus into the green roof outflow. This field study demonstrated the importance of green roof media selection in locations where nutrients are a concern.