Saturated Buffers: What Is Their Potential Impact across the US Midwest?

Abstract

© 2019 The Authors Core Ideas: Saturated buffers can help achieve regional water quality goals. Roughly 75,520 km of US Midwest stream banks could host a saturated buffer. 248,000 to 360,000 saturated buffers could be implemented across the Midwest. Saturated buffers could potentially treat 3.85 million ha of Midwest drained land. Wide implementation could result in a 5–10% overall tile drainage N load reduction. Because saturated buffers are a new conservation practice, there has been no large-scale assessment of their potential to aid in meeting water quality goals. Publicly available data were used in a stepwise fashion within a geographic information system to estimate the total stream length suitable for saturated buffer implementation across the US Midwest region and the resulting potential nitrate loading reduction from widespread saturated buffer implementation. Approximately 37,760 km of streams (or 75,520 km of stream bank) was deemed suitable to host a saturated buffer, and 3.85 million ha of drained land has the potential to drain to a saturated buffer. These results suggest that implementing saturated buffers widely could result in a 5 to 10% reduction of the estimated N load from midwestern tile-drained land. Saturated buffers can be an important component of plans to achieve water quality goals.