MATTOLE RIVER - ETTERSBURG (ETTC1)
Latitude: 40.14º NLongitude: 123.99º WElevation: 579 FeetForecast Type: Unofficial Location
Location: Humboldt County in CaliforniaBulletin Group: North CoastRiver Group: North Coast
Issuance Time: Apr 20 2026 at 6:49 AM PDTNext Issuance: Apr 21 2026 at 9:00 AM PDT
Action/Monitor: N/A Minor Flood: N/A Moderate Flood: N/A Major Flood: N/A

# Tabular Observed and Forecast Hydrograph Information
#
# Location: Mattole River - Ettersburg (ETTC1)
#
# File Generation Time:  04/20/2026 at 06:51 AM PDT
# Data Interval:  1 Hour
#
# Most Recent Date & Time of Maximum Observed:  04/15/2026 at 11:00 PM PDT
# Maximum Observed Stage:                       9.75 Feet
# Maximum Observed Flow:                        160 cfs
#
# Earliest Date & Time of Maximum Forecast:     04/22/2026 at 12:00 AM PDT
# Maximum Forecast Stage:                       10.81 Feet
# Maximum Forecast Flow:                        367 cfs
#
# OBSERVED
#
# Date & Time  (Local)    Stage (Feet)     Flow (cfs)     Trend     Observed Status
# ---------------------------------------------------------------------------------
  04/15/2026 06 AM PDT            9.75            160                Not Applicable
  04/15/2026 07 AM PDT            9.75            160         0      Not Applicable
  04/15/2026 08 AM PDT            9.73            157         -      Not Applicable
  04/15/2026 09 AM PDT            9.73            157         0      Not Applicable
  04/15/2026 10 AM PDT            9.73            157         0      Not Applicable
  04/15/2026 11 AM PDT            9.73            157         0      Not Applicable
  04/15/2026 12 PM PDT            9.72            155         -      Not Applicable
  04/15/2026 01 PM PDT            9.71            154         -      Not Applicable
  04/15/2026 02 PM PDT            9.72            155         +      Not Applicable
  04/15/2026 03 PM PDT            9.70            152         -      Not Applicable
  04/15/2026 04 PM PDT            9.71            154         +      Not Applicable
  04/15/2026 05 PM PDT            9.71            154         0      Not Applicable
  04/15/2026 06 PM PDT            9.72            155         +      Not Applicable
  04/15/2026 07 PM PDT            9.73            157         +      Not Applicable
  04/15/2026 08 PM PDT            9.74            158         +      Not Applicable
  04/15/2026 09 PM PDT            9.74            158         0      Not Applicable
  04/15/2026 10 PM PDT            9.75            160         +      Not Applicable
  04/15/2026 11 PM PDT            9.75            160         0      Not Applicable
  04/16/2026 12 AM PDT            9.73            157         -      Not Applicable
  04/16/2026 01 AM PDT            9.71            154         -      Not Applicable
  04/16/2026 02 AM PDT            9.70            152         -      Not Applicable
  04/16/2026 03 AM PDT            9.69            150         -      Not Applicable
  04/16/2026 04 AM PDT            9.69            150         0      Not Applicable
  04/16/2026 05 AM PDT            9.67            147         -      Not Applicable
  04/16/2026 06 AM PDT            9.67            147         0      Not Applicable
  04/16/2026 07 AM PDT            9.66            146         -      Not Applicable
  04/16/2026 08 AM PDT            9.66            146         0      Not Applicable
  04/16/2026 09 AM PDT            9.65            144         -      Not Applicable
  04/16/2026 10 AM PDT            9.64            143         -      Not Applicable
  04/16/2026 11 AM PDT            9.63            141         -      Not Applicable
  04/16/2026 12 PM PDT            9.63            141         0      Not Applicable
  04/16/2026 01 PM PDT            9.63            141         0      Not Applicable
  04/16/2026 02 PM PDT            9.61            138         -      Not Applicable
  04/16/2026 03 PM PDT            9.62            140         +      Not Applicable
  04/16/2026 04 PM PDT            9.60            137         -      Not Applicable
  04/16/2026 05 PM PDT            9.60            137         0      Not Applicable
  04/16/2026 06 PM PDT            9.59            135         -      Not Applicable
  04/16/2026 07 PM PDT            9.58            134         -      Not Applicable
  04/16/2026 08 PM PDT            9.58            134         0      Not Applicable
  04/16/2026 09 PM PDT            9.58            134         0      Not Applicable
  04/16/2026 10 PM PDT            9.57            132         -      Not Applicable
  04/16/2026 11 PM PDT            9.57            132         0      Not Applicable
  04/17/2026 12 AM PDT            9.56            131         -      Not Applicable
  04/17/2026 01 AM PDT            9.55            129         -      Not Applicable
  04/17/2026 02 AM PDT            9.56            131         +      Not Applicable
  04/17/2026 03 AM PDT            9.55            129         -      Not Applicable
  04/17/2026 04 AM PDT            9.55            129         0      Not Applicable
  04/17/2026 05 AM PDT            9.54            128         -      Not Applicable
  04/17/2026 06 AM PDT            9.53            126         -      Not Applicable
  04/17/2026 07 AM PDT            9.53            126         0      Not Applicable
  04/17/2026 08 AM PDT            9.53            126         0      Not Applicable
  04/17/2026 09 AM PDT            9.53            126         0      Not Applicable
  04/17/2026 10 AM PDT            9.53            126         0      Not Applicable
  04/17/2026 11 AM PDT            9.52            125         -      Not Applicable
  04/17/2026 12 PM PDT            9.52            125         0      Not Applicable
  04/17/2026 01 PM PDT            9.52            125         0      Not Applicable
  04/17/2026 02 PM PDT            9.53            126         +      Not Applicable
  04/17/2026 03 PM PDT            9.52            125         -      Not Applicable
  04/17/2026 04 PM PDT            9.52            125         0      Not Applicable
  04/17/2026 05 PM PDT            9.51            124         -      Not Applicable
  04/17/2026 06 PM PDT            9.50            122         -      Not Applicable
  04/17/2026 07 PM PDT            9.50            122         0      Not Applicable
  04/17/2026 08 PM PDT            9.49            121         -      Not Applicable
  04/17/2026 09 PM PDT            9.49            121         0      Not Applicable
  04/17/2026 10 PM PDT            9.49            121         0      Not Applicable
  04/17/2026 11 PM PDT            9.48            119         -      Not Applicable
  04/18/2026 12 AM PDT            9.47            118         -      Not Applicable
  04/18/2026 01 AM PDT            9.47            118         0      Not Applicable
  04/18/2026 02 AM PDT            9.47            118         0      Not Applicable
  04/18/2026 03 AM PDT            9.47            118         0      Not Applicable
  04/18/2026 04 AM PDT            9.46            117         -      Not Applicable
  04/18/2026 05 AM PDT            9.46            117         0      Not Applicable
  04/18/2026 06 AM PDT            9.45            115         -      Not Applicable
  04/18/2026 07 AM PDT            9.45            115         0      Not Applicable
  04/18/2026 08 AM PDT            9.44            114         -      Not Applicable
  04/18/2026 09 AM PDT            9.45            115         +      Not Applicable
  04/18/2026 10 AM PDT            9.45            115         0      Not Applicable
  04/18/2026 11 AM PDT            9.45            115         0      Not Applicable
  04/18/2026 12 PM PDT            9.44            114         -      Not Applicable
  04/18/2026 01 PM PDT            9.45            115         +      Not Applicable
  04/18/2026 02 PM PDT            9.45            115         0      Not Applicable
  04/18/2026 03 PM PDT            9.45            115         0      Not Applicable
  04/18/2026 04 PM PDT            9.44            114         -      Not Applicable
  04/18/2026 05 PM PDT            9.44            114         0      Not Applicable
  04/18/2026 06 PM PDT            9.43            112         -      Not Applicable
  04/18/2026 07 PM PDT            9.42            111         -      Not Applicable
  04/18/2026 08 PM PDT            9.43            112         +      Not Applicable
  04/18/2026 09 PM PDT            9.42            111         -      Not Applicable
  04/18/2026 10 PM PDT            9.41            110         -      Not Applicable
  04/18/2026 11 PM PDT            9.42            111         +      Not Applicable
  04/19/2026 12 AM PDT            9.41            110         -      Not Applicable
  04/19/2026 01 AM PDT            9.41            110         0      Not Applicable
  04/19/2026 02 AM PDT            9.40            108         -      Not Applicable
  04/19/2026 03 AM PDT            9.40            108         0      Not Applicable
  04/19/2026 04 AM PDT            9.40            108         0      Not Applicable
  04/19/2026 05 AM PDT            9.40            108         0      Not Applicable
  04/19/2026 06 AM PDT            9.39            107         -      Not Applicable
  04/19/2026 07 AM PDT            9.39            107         0      Not Applicable
  04/19/2026 08 AM PDT            9.39            107         0      Not Applicable
  04/19/2026 09 AM PDT            9.39            107         0      Not Applicable
  04/19/2026 10 AM PDT            9.39            107         0      Not Applicable
  04/19/2026 11 AM PDT            9.39            107         0      Not Applicable
  04/19/2026 12 PM PDT            9.39            107         0      Not Applicable
  04/19/2026 01 PM PDT            9.38            106         -      Not Applicable
  04/19/2026 02 PM PDT            9.39            107         +      Not Applicable
  04/19/2026 03 PM PDT            9.39            107         0      Not Applicable
  04/19/2026 04 PM PDT            9.38            106         -      Not Applicable
  04/19/2026 05 PM PDT            9.38            106         0      Not Applicable
  04/19/2026 06 PM PDT            9.37            104         -      Not Applicable
  04/19/2026 07 PM PDT            9.37            104         0      Not Applicable
  04/19/2026 08 PM PDT            9.36            103         -      Not Applicable
  04/19/2026 09 PM PDT            9.36            103         0      Not Applicable
  04/19/2026 10 PM PDT            9.36            103         0      Not Applicable
  04/19/2026 11 PM PDT            9.36            103         0      Not Applicable
  04/20/2026 12 AM PDT            9.36            103         0      Not Applicable
  04/20/2026 01 AM PDT            9.36            103         0      Not Applicable
  04/20/2026 02 AM PDT            9.35            102         -      Not Applicable
  04/20/2026 03 AM PDT            9.35            102         0      Not Applicable
  04/20/2026 04 AM PDT            9.35            102         0      Not Applicable
  04/20/2026 05 AM PDT            9.37            104         +      Not Applicable
  04/20/2026 06 AM PDT            9.37            104         0      Not Applicable
#
# FORECAST
#
# Date & Time  (Local)    Stage (Feet)     Flow (cfs)     Trend     Forecast Status
# ---------------------------------------------------------------------------------
  04/20/2026 07 AM PDT            9.38            106                Not Applicable
  04/20/2026 08 AM PDT            9.38            106         0      Not Applicable
  04/20/2026 09 AM PDT            9.39            107         +      Not Applicable
  04/20/2026 10 AM PDT            9.42            111         +      Not Applicable
  04/20/2026 11 AM PDT            9.47            118         +      Not Applicable
  04/20/2026 12 PM PDT            9.59            135         +      Not Applicable
  04/20/2026 01 PM PDT            9.80            168         +      Not Applicable
  04/20/2026 02 PM PDT           10.07            215         +      Not Applicable
  04/20/2026 03 PM PDT           10.30            258         +      Not Applicable
  04/20/2026 04 PM PDT           10.48            295         +      Not Applicable
  04/20/2026 05 PM PDT           10.61            322         +      Not Applicable
  04/20/2026 06 PM PDT           10.70            342         +      Not Applicable
  04/20/2026 07 PM PDT           10.75            353         +      Not Applicable
  04/20/2026 08 PM PDT           10.79            362         +      Not Applicable
  04/20/2026 09 PM PDT           10.79            362         0      Not Applicable
  04/20/2026 10 PM PDT           10.78            360         -      Not Applicable
  04/20/2026 11 PM PDT           10.75            353         -      Not Applicable
  04/21/2026 12 AM PDT           10.70            342         -      Not Applicable
  04/21/2026 01 AM PDT           10.65            331         -      Not Applicable
  04/21/2026 02 AM PDT           10.59            318         -      Not Applicable
  04/21/2026 03 AM PDT           10.53            305         -      Not Applicable
  04/21/2026 04 AM PDT           10.49            297         -      Not Applicable
  04/21/2026 05 AM PDT           10.45            288         -      Not Applicable
  04/21/2026 06 AM PDT           10.43            284         -      Not Applicable
  04/21/2026 07 AM PDT           10.41            280         -      Not Applicable
  04/21/2026 08 AM PDT           10.40            278         -      Not Applicable
  04/21/2026 09 AM PDT           10.40            278         0      Not Applicable
  04/21/2026 10 AM PDT           10.40            278         0      Not Applicable
  04/21/2026 11 AM PDT           10.41            280         +      Not Applicable
  04/21/2026 12 PM PDT           10.42            282         +      Not Applicable
  04/21/2026 01 PM PDT           10.44            286         +      Not Applicable
  04/21/2026 02 PM PDT           10.45            288         +      Not Applicable
  04/21/2026 03 PM PDT           10.48            295         +      Not Applicable
  04/21/2026 04 PM PDT           10.52            303         +      Not Applicable
  04/21/2026 05 PM PDT           10.56            312         +      Not Applicable
  04/21/2026 06 PM PDT           10.61            322         +      Not Applicable
  04/21/2026 07 PM PDT           10.67            335         +      Not Applicable
  04/21/2026 08 PM PDT           10.72            347         +      Not Applicable
  04/21/2026 09 PM PDT           10.76            356         +      Not Applicable
  04/21/2026 10 PM PDT           10.79            362         +      Not Applicable
  04/21/2026 11 PM PDT           10.80            365         +      Not Applicable
  04/22/2026 12 AM PDT           10.81            367         +      Not Applicable
  04/22/2026 01 AM PDT           10.81            367         0      Not Applicable
  04/22/2026 02 AM PDT           10.80            365         -      Not Applicable
  04/22/2026 03 AM PDT           10.79            362         -      Not Applicable
  04/22/2026 04 AM PDT           10.77            358         -      Not Applicable
  04/22/2026 05 AM PDT           10.74            351         -      Not Applicable
  04/22/2026 06 AM PDT           10.71            344         -      Not Applicable
  04/22/2026 07 AM PDT           10.68            338         -      Not Applicable
  04/22/2026 08 AM PDT           10.63            327         -      Not Applicable
  04/22/2026 09 AM PDT           10.56            312         -      Not Applicable
  04/22/2026 10 AM PDT           10.46            291         -      Not Applicable
  04/22/2026 11 AM PDT           10.36            270         -      Not Applicable
  04/22/2026 12 PM PDT           10.29            256         -      Not Applicable
  04/22/2026 01 PM PDT           10.25            248         -      Not Applicable
  04/22/2026 02 PM PDT           10.23            245         -      Not Applicable
  04/22/2026 03 PM PDT           10.22            243         -      Not Applicable
  04/22/2026 04 PM PDT           10.22            243         0      Not Applicable
  04/22/2026 05 PM PDT           10.22            243         0      Not Applicable
  04/22/2026 06 PM PDT           10.22            243         0      Not Applicable
  04/22/2026 07 PM PDT           10.22            243         0      Not Applicable
  04/22/2026 08 PM PDT           10.22            243         0      Not Applicable
  04/22/2026 09 PM PDT           10.22            243         0      Not Applicable
  04/22/2026 10 PM PDT           10.22            243         0      Not Applicable
  04/22/2026 11 PM PDT           10.22            243         0      Not Applicable
  04/23/2026 12 AM PDT           10.22            243         0      Not Applicable
  04/23/2026 01 AM PDT           10.21            241         -      Not Applicable
  04/23/2026 02 AM PDT           10.21            241         0      Not Applicable
  04/23/2026 03 AM PDT           10.20            239         -      Not Applicable
  04/23/2026 04 AM PDT           10.19            237         -      Not Applicable
  04/23/2026 05 AM PDT           10.19            237         0      Not Applicable
  04/23/2026 06 AM PDT           10.18            235         -      Not Applicable
  04/23/2026 07 AM PDT           10.17            233         -      Not Applicable
  04/23/2026 08 AM PDT           10.16            231         -      Not Applicable
  04/23/2026 09 AM PDT           10.16            231         0      Not Applicable
  04/23/2026 10 AM PDT           10.15            229         -      Not Applicable
  04/23/2026 11 AM PDT           10.14            227         -      Not Applicable
  04/23/2026 12 PM PDT           10.14            227         0      Not Applicable
  04/23/2026 01 PM PDT           10.13            226         -      Not Applicable
  04/23/2026 02 PM PDT           10.12            224         -      Not Applicable
  04/23/2026 03 PM PDT           10.12            224         0      Not Applicable
  04/23/2026 04 PM PDT           10.11            222         -      Not Applicable
  04/23/2026 05 PM PDT           10.10            220         -      Not Applicable
  04/23/2026 06 PM PDT           10.09            218         -      Not Applicable
  04/23/2026 07 PM PDT           10.09            218         0      Not Applicable
  04/23/2026 08 PM PDT           10.08            216         -      Not Applicable
  04/23/2026 09 PM PDT           10.07            215         -      Not Applicable
  04/23/2026 10 PM PDT           10.06            213         -      Not Applicable
  04/23/2026 11 PM PDT           10.06            213         0      Not Applicable
  04/24/2026 12 AM PDT           10.05            211         -      Not Applicable
  04/24/2026 01 AM PDT           10.04            209         -      Not Applicable
  04/24/2026 02 AM PDT           10.04            209         0      Not Applicable
  04/24/2026 03 AM PDT           10.03            207         -      Not Applicable
  04/24/2026 04 AM PDT           10.03            207         0      Not Applicable
  04/24/2026 05 AM PDT           10.02            206         -      Not Applicable
  04/24/2026 06 AM PDT           10.01            204         -      Not Applicable
  04/24/2026 07 AM PDT           10.01            204         0      Not Applicable
  04/24/2026 08 AM PDT           10.00            202         -      Not Applicable
  04/24/2026 09 AM PDT            9.99            200         -      Not Applicable
  04/24/2026 10 AM PDT            9.98            199         -      Not Applicable
  04/24/2026 11 AM PDT            9.98            199         0      Not Applicable
  04/24/2026 12 PM PDT            9.97            197         -      Not Applicable
  04/24/2026 01 PM PDT            9.97            197         0      Not Applicable
  04/24/2026 02 PM PDT            9.96            195         -      Not Applicable
  04/24/2026 03 PM PDT            9.95            193         -      Not Applicable
  04/24/2026 04 PM PDT            9.95            193         0      Not Applicable
  04/24/2026 05 PM PDT            9.94            192         -      Not Applicable
  04/24/2026 06 PM PDT            9.94            192         0      Not Applicable
  04/24/2026 07 PM PDT            9.93            190         -      Not Applicable
  04/24/2026 08 PM PDT            9.92            188         -      Not Applicable
  04/24/2026 09 PM PDT            9.92            188         0      Not Applicable
  04/24/2026 10 PM PDT            9.91            186         -      Not Applicable
  04/24/2026 11 PM PDT            9.90            185         -      Not Applicable
  04/25/2026 12 AM PDT            9.90            185         0      Not Applicable
  04/25/2026 01 AM PDT            9.89            183         -      Not Applicable
  04/25/2026 02 AM PDT            9.89            183         0      Not Applicable
  04/25/2026 03 AM PDT            9.88            181         -      Not Applicable
  04/25/2026 04 AM PDT            9.88            181         0      Not Applicable
  04/25/2026 05 AM PDT            9.87            180         -      Not Applicable
#
# NOTE 1: Stages are rounded to the nearest hundredth (.01) of a foot.
# NOTE 2: Flows are rounded to the nearest (1) cfs.
# NOTE 3: Trends are determined using hourly change in unrounded stage and flow.
# NOTE 4: Maximum Values are determined using unrounded stage and flow.