River networks can significantly influence N exports to coastal zones, especially during low flow periods. A fuller evaluation of their importance requires an annual perspective encompassing high flow periods when most material fluxes occur. We explored N removal by an entire 5^th order river network over annual time scales using a daily time step, spatially distributed, DIN removal model applied to the 2000-2003 period. Biological activity was defined by a Michaelis-Menten function based on ¹⁵N addition experiments (LINX2) conducted during summers in the Ipswich R. watershed. To scale activity over the entire year, we applied a Q10 function (Q10=2). Distributed DIN inputs were based on mean annual DIN concentration vs. land use relationships and observed runoff. Predicted DIN concentrations at the basin mouth corresponded well with observations during low flow periods (discharge < 1 m3/s), when removal ranged between 30 and 90% of inputs depending on temperature and flow. During high flow periods (> 1m3/s) predicted DIN concentrations were consistently high, suggesting modeled N removal was too low. Discrepancies were pronounced during late spring, consistent with an important floodplain role. Large river processes will need to be better understood to evaluate river network influence on annual N exports.