HOBO data loggers were used exclusively this year to monitor stage height and water temperature
HOBO: Depth and water temperature are recorded by the HOBO data logger. Depths are corrected for barometric pressure changes using readings in an additional HOBO datalogger deployed at Marshview Farm. The HOBO is deployed in a a PVC tube, which was attached to ree-bar driven into the stream bed. The PVC tube has holes drilled to allow adequate water circulation.
NOTES AND COMMENTS:
Velocity measurements were made using a Marsh McBirney current meter. Discharge estimates in Cedar Swamp (Bear Br.) are based on a power rating curve that contains measurements up to a depth of 0.9 meters, as standardized to depth measured with the HOBO datalogger (Column = HOBO_Depth), which is above bankfull stage. Rating curve has been standardized to HOBO_Depth to allow application of a single rating curve across years. Rating curve has an R2 of 0.96 using 10 measurements between 2005 and 2007. All files in this series are currently standardized to HOBO_depth.
The column Depth_Device is included when combining files from several years, over which several different devices were used to calculate depth. HOBO_Depth is the depth that is standardized across all measurement devices so that a single rating curve can be applied.
CALCULATIONS:
Discharge rating curve :
Discharge (l/s) = 1085.3 (depth) ^ 4.5944
where depth is HOBO_Depth
Measurements in 2008 do not suggest that the rating curve has changed since 2007. However, the rating curve is subject to change in the future as more measurements are taken.
