18A050 Dungeness River nr Mouth Technical Notes: 2007 Water Year Christopher Evans Introduction Ecology’s telemetry stream gage on the Dungeness River is located at the Sequim- Dungeness Way Bridge. This report encompasses the water year 2007. Stage Record During water year 2007, data was recorded every 15 minutes from October 1, 2006 through September 30, 2007. The recorded range of stage for the period of record was 6.20 ft. The daily mean discharge table reports reliable discharge values between two times the highest measured discharge and one-half the lowest measured discharge. Data outside of this range are considered an unreliable estimate and are not reported. Logged data that has drifted more than 20% from direct observed gage heights is coded as an estimate (50). With the exception of a December high water event, all stage data was within the reliable range of the rating during the water year 2007 period of record. Annual Mean: 410 cubic feet per second (cfs) Annual Median: 367 cfs Max. Daily Mean: 2260 cfs Min. Daily Mean: 58 cfs Instantaneous Max: 2850 cfs Instantaneous Min: 56 cfs Time-weighted discharge duration: Discharge during water year 2006 exceeded 77 cfs 90% of the time and exceeded 716 cfs 10% of the time. The average percent difference between the logged discharge and actual field verified discharge was 2%. The average difference between the logged and actual discharge was 13 cfs. Rating Summary Two rating curves were used during water year 2007. The average percent difference between measured and predicted discharge for these two ratings is 7%. The cross section remained stable throughout winter 2007. The cross section filled into the summer of 2007 and was subsequently transitioned into a new rating on the downward limb of the hydrograph.