Alternative Methods for Monitoring Surface-Water Runoff From Agricultural Fields.

One of the challenges in choosing a surface-water monitoring protocol is that the trade-off between accuracy and cost is not well defined. Therefore, it is difficult to decide what monitoring strategy is most appropriate and cost effective. For this reason, we are evaluating the following four alternative surface-water monitoring systems:

1)      automated time-based composite sampling with real-time remote site operation,

2)      automated flow-weight composite sampling,

3)      passive siphon sampling with stage recorder, and

4)      passive stand-pipe flow splitter sampling.

Evaluations of the alternative sampling protocols will be based on relative error and precision of load and discharge estimates as well as equipment and operational costs. Results presented will include analysis of 2010 water-year field runoff events at Pioneer Farm for alternatives 1, 2, and 3 (above) and the results of laboratory investigations of the passive stand-pipe flow splitter.