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Hydrograph River at a Glance Download
Willow Brook at Penngrove Park Stage (ft)Highest Observation: 54.54 ft at 9:00PM Mar 13, 2024Highest Observation: 54.54 ft at 10:00PM Mar 13, 2024Highest Observation: 54.54 ft at 11:00PM Mar 13, 2024Highest Observation: 54.54 ft at 12:00AM Mar 14, 2024Highest Observation: 54.54 ft at 1:00AM Mar 14, 2024Highest Observation: 54.54 ft at 2:00AM Mar 14, 2024Highest Observation: 54.54 ft at 3:00AM Mar 14, 2024Highest Observation: 54.54 ft at 4:00AM Mar 14, 2024Highest Observation: 54.54 ft at 5:00AM Mar 14, 2024Highest Observation: 54.54 ft at 6:00AM Mar 14, 2024Observed: 54.49 ft at 8:00AM Mar 14, 2024Observed: 54.49 ft at 9:00AM Mar 14, 2024Observed: 54.47 ft at 10:00AM Mar 14, 2024Observed: 54.47 ft at 11:00AM Mar 14, 2024Observed: 54.49 ft at 12:00PM Mar 14, 2024Observed: 54.49 ft at 1:00PM Mar 14, 2024Observed: 54.49 ft at 2:00PM Mar 14, 2024Observed: 54.49 ft at 3:00PM Mar 14, 2024Observed: 54.52 ft at 5:00PM Mar 14, 2024Observed: 54.52 ft at 6:00PM Mar 14, 2024Observed: 54.52 ft at 7:00PM Mar 14, 2024Observed: 54.52 ft at 8:00PM Mar 14, 2024Observed: 54.52 ft at 9:00PM Mar 14, 2024Observed: 54.52 ft at 10:00PM Mar 14, 2024Highest Observation: 54.54 ft at 11:00PM Mar 14, 2024Observed: 54.52 ft at 12:00AM Mar 15, 2024Observed: 54.52 ft at 1:00AM Mar 15, 2024Observed: 54.52 ft at 2:00AM Mar 15, 2024Observed: 54.52 ft at 4:00AM Mar 15, 2024Observed: 54.52 ft at 5:00AM Mar 15, 2024Observed: 54.52 ft at 6:00AM Mar 15, 2024Observed: 54.52 ft at 7:00AM Mar 15, 2024Observed: 54.49 ft at 7:58AM Mar 15, 2024Observed: 54.47 ft at 9:00AM Mar 15, 2024Observed: 54.47 ft at 10:00AM Mar 15, 2024Observed: 54.47 ft at 11:00AM Mar 15, 2024Observed: 54.47 ft at 12:00PM Mar 15, 2024Observed: 54.47 ft at 2:00PM Mar 15, 2024Observed: 54.49 ft at 3:00PM Mar 15, 2024Observed: 54.49 ft at 4:00PM Mar 15, 2024Observed: 54.52 ft at 5:00PM Mar 15, 2024Observed: 54.52 ft at 6:00PM Mar 15, 2024Observed: 54.52 ft at 7:00PM Mar 15, 2024Highest Observation: 54.54 ft at 8:00PM Mar 15, 2024Highest Observation: 54.54 ft at 9:00PM Mar 15, 2024Highest Observation: 54.54 ft at 10:00PM Mar 15, 2024Highest Observation: 54.54 ft at 11:00PM Mar 15, 2024Highest Observation: 54.54 ft at 12:00AM Mar 16, 2024Highest Observation: 54.54 ft at 1:00AM Mar 16, 2024Highest Observation: 54.54 ft at 2:00AM Mar 16, 2024Highest Observation: 54.54 ft at 3:00AM Mar 16, 2024Highest Observation: 54.54 ft at 4:00AM Mar 16, 2024Highest Observation: 54.54 ft at 5:00AM Mar 16, 2024Observed: 54.52 ft at 7:00AM Mar 16, 2024Observed: 54.49 ft at 8:00AM Mar 16, 2024Observed: 54.47 ft at 10:00AM Mar 16, 2024Observed: 54.47 ft at 11:00AM Mar 16, 2024Observed: 54.47 ft at 12:00PM Mar 16, 2024Observed: 54.49 ft at 1:00PM Mar 16, 2024Observed: 54.49 ft at 2:00PM Mar 16, 2024Observed: 54.49 ft at 3:00PM Mar 16, 2024Observed: 54.52 ft at 4:00PM Mar 16, 2024Observed: 54.52 ft at 5:00PM Mar 16, 2024Observed: 54.52 ft at 6:00PM Mar 16, 2024Highest Observation: 54.54 ft at 7:00PM Mar 16, 2024Highest Observation: 54.54 ft at 9:00PM Mar 16, 2024Highest Observation: 54.54 ft at 10:00PM Mar 16, 2024Highest Observation: 54.54 ft at 11:00PM Mar 16, 2024Highest Observation: 54.54 ft at 12:00AM Mar 17, 2024Highest Observation: 54.54 ft at 1:00AM Mar 17, 2024Highest Observation: 54.54 ft at 2:00AM Mar 17, 2024Highest Observation: 54.54 ft at 3:00AM Mar 17, 2024Highest Observation: 54.54 ft at 4:00AM Mar 17, 2024Observed: 54.52 ft at 5:00AM Mar 17, 2024Observed: 54.52 ft at 6:00AM Mar 17, 2024Observed: 54.49 ft at 8:00AM Mar 17, 2024Observed: 54.47 ft at 10:00AM Mar 17, 2024Observed: 54.47 ft at 11:00AM Mar 17, 2024Observed: 54.47 ft at 12:00PM Mar 17, 2024Observed: 54.49 ft at 1:00PM Mar 17, 2024Observed: 54.49 ft at 2:00PM Mar 17, 2024Observed: 54.49 ft at 3:00PM Mar 17, 2024Observed: 54.52 ft at 4:00PM Mar 17, 2024Observed: 54.52 ft at 5:00PM Mar 17, 2024Observed: 54.52 ft at 6:00PM Mar 17, 2024Observed: 54.52 ft at 7:00PM Mar 17, 2024Highest Observation: 54.54 ft at 8:00PM Mar 17, 2024Highest Observation: 54.54 ft at 9:00PM Mar 17, 2024Highest Observation: 54.54 ft at 10:00PM Mar 17, 2024Highest Observation: 54.54 ft at 11:00PM Mar 17, 2024Highest Observation: 54.54 ft at 12:00AM Mar 18, 2024Highest Observation: 54.54 ft at 1:00AM Mar 18, 2024Highest Observation: 54.54 ft at 2:00AM Mar 18, 2024Highest Observation: 54.54 ft at 3:00AM Mar 18, 2024Highest Observation: 54.54 ft at 4:00AM Mar 18, 2024Observed: 54.52 ft at 5:00AM Mar 18, 2024Observed: 54.52 ft at 6:00AM Mar 18, 2024Observed: 54.52 ft at 7:00AM Mar 18, 2024Observed: 54.52 ft at 8:00AM Mar 18, 2024Observed: 54.49 ft at 9:00AM Mar 18, 2024Observed: 54.47 ft at 10:00AM Mar 18, 2024Observed: 54.49 ft at 12:00PM Mar 18, 2024Observed: 54.49 ft at 2:00PM Mar 18, 2024Observed: 54.49 ft at 3:00PM Mar 18, 2024PFSC1(plotting HGIRR) Graph Created (8:00PM Mar 18, 2024)ObservedLatest observed value: 54.49 ft at 3:00 PM PDT 18-Mar-2024. Flood Stage is 60.7 ft
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About this graph
Tabular Data (UTC)
Tabular Data (PDT)
XML Data
RSS Files
Datum: NGVD29
Metadata
NOTE: Graphical forecasts are not available for the Willow Brook at Penngrove Park. During times of high water, forecast crest information can be found in the text products.
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Flood Categories (in feet)
Major Flood Stage: 61.7
Moderate Flood Stage: 61.2
Flood Stage: 60.7
Action Stage: 58.7
Low Stage (in feet): -9999

Historic Crests
Currently none available.

Recent Crests
Currently none available.

Low Water Records
Currently none available.
Zoom Level:16
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Gauge LocationGauge Map Marker
Disclaimer
Latitude/Longitude Disclaimer: The gauge location shown in the above map is the approximate location based on the latitude/longitude coordinates provided to the NWS by the gauge owner.
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If you notice any errors in the below information, please contact our Webmaster
62.8 Record stage for this site (2005 floods).
62.5 Water reaches the gazebo floor.
62 Critical threshold at which 2 downstream locations may flood in 2 to 4 hours.
61.7 Major Flood Stage. NWS will issue a Flash Flood Warning if not already issued. At this level, water levels are high in the Petaluma River Basin and adjacent areas. Other creeks in the area are likely flooding.
61.2 Moderate Flood Stage. City of Petalum will evaluate the need to activate the Emergency Operations Center. NWS may issue an Urban/Small Stream Advisory for this level of flooding.
60.7 Minor Flood Stage. Water is above bankfull and minor flooding begins. City of Petaluma Fire Chief, Watch Commander, and Water Resources anc Conservation Director notified. NWS will likely issue an Urban/Small Stream Advisory.
58.7 Action Stage. Situation is being monitored closely by NWS and City of Petaluma.
About This Location Collapse

Latitude: 38.294444° N, Longitude: 122.663056° W, Horizontal Datum: NAD83/WGS84

River Stage
Reference Frame
Gauge Height Flood Stage Uses
NWS stage 0 ft 60.7 ft Interpreting hydrographs and NWS watch, warnings, and forecasts, and inundation maps
Vertical Datum Elevation
(gauge height = 0)
Elevation
(gauge height = flood stage)
Elevation information source
NAVD88 Not Available Not Available Survey grade GPS equipment, FEMA flood plain maps, newer USGS topographic maps
NGVD 29 Not Available Not Available Older USGS topographic maps, NGVD29 benchmarks
MSL Not Available Not Available Older USGS topographic maps, MSL benchmarks
Other Not Available Not Available  
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The National Weather Service prepares its forecasts and other services in collaboration with agencies like the US Geological Survey, US Bureau of Reclamation, US Army Corps of Engineers, Natural Resource Conservation Service, National Park Service, ALERT Users Group, Bureau of Indian Affairs, and many state and local emergency managers across the country. For details, please click here.
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Page last modified: 2-Nov-2020 7:27 PM
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