Water quality in Alleman Creek, a small watershed in Iowa,
will be monitored through stream nitrate sampling and streamflow monitoring. Nearly all
subsurface drainage tile outlets in this watershed were treated with an edge-of-field
nitrogen reduction practice (saturated buffer or denitrifying bioreactor) as part of the first
Polk County Batch and Build Project. This project will assess the effectiveness of these
edge-of-field practices at scale by quantifying the reduction in nitrogen mass leaving the
watershed. This watershed assessment will be contextualized with nitrate mass reduction
monitoring of three individual saturated buffers in the watershed. This research will
provide valuable empirical data on the effectiveness of edge-of-field water quality
practices at a larger scale as widespread implementation of these practices accelerates to
meet water quality goals.