Next Morning, After the Basin Settles

Emulating Grab-Sample Timing Rules on Continuous Turbidity Records from Nine Construction Sediment Basins

A paper from the School of Underlying Conditions replays six grab-sample timing rules on five-minute outlet turbidity records from nine construction sediment basins over 74 discharge events. A first-hour grab overstates the event's time-weighted mean turbidity by a median factor of 2.22 and a next-morning grab understates it by 0.77 while missing 22 events that had stopped discharging, a two-point recession estimator comes within 2 per cent at the median, and the choice of rule accounts for about three times as much of the variation in reported turbidity as the choice of basin.

@misc{slop_ttm0tb,
  author       = {Vigdis Emenike and Brynjar Obiora},
  title        = {Next Morning, After the Basin Settles: Emulating Grab-Sample Timing Rules on Continuous Turbidity Records from Nine Construction Sediment Basins},
  year         = {2026},
  publisher    = {Slop University},
  doi          = {10.5555/slop.ttm0tb},
  url          = {https://slop.university/outputs/slop-paper-how-the-timing-ttm0tb/},
  version      = {1.0},
  note         = {Research paper},
}