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Hydrograph River at a Glance Download
Conn Creek at Lake Hennessey Stage (ft)Observed: 0.06 ft at 11:25AM Oct 23, 2021Observed: 0.06 ft at 11:30AM Oct 23, 2021Highest Observation: 0.07 ft at 11:25AM Oct 24, 2021Highest Observation: 0.07 ft at 11:30AM Oct 24, 2021CVZC1(plotting HGIRR) Graph Created (3:30AM Oct 27, 2021)ObservedLatest observed value: 0.07 ft at 11:30 AM PDT 24-Oct-2021. Flood Stage is 10.2 ft
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Tabular Data (UTC)
Tabular Data (PDT)
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Datum: Not Available
NOTE: Graphical forecasts are not available for the Conn Creek at Lake Hennessey. 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: 16
Moderate Flood Stage: 13.2
Flood Stage: 10.2
Action Stage: 8
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
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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16 Major Flood Stage. Water is several feet deep across floodplain on northern side of creek. Vineyards and local properties flooded, possibly exacerbated by backwatering of Lake Hennessey below. Local creek crossings inundated and impassable.
13.2 Moderate Flood Stage. Water spilling onto left bank floodplain (north side of creek). Local crossings flooded and backwatered.
10.2 Minor Flood Stage. Backwatering begins at local bridge crossings. Water level is approaching elevation of bridge decks, with possible overflow. NWS will issue a Flash Flood Warning if not yet already issued.
8 Monitor Stage. Water is 2 feet below backwatering at local landowner crossing at gaging site. NWS will issue a Flash Flood Watch if not yet already issued.
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Latitude: 38.508056° N, Longitude: 122.406111° W, Horizontal Datum: NAD83/WGS84

River Stage
Reference Frame
Gauge Height Flood Stage Uses
NWS stage 0 ft 10.2 ft Interpreting hydrographs and NWS watch, warnings, and forecasts, and inundation maps
Vertical Datum Elevation
(gauge height = 0)
(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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Monterey, CA 93943-5505
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Page last modified: 2-Nov-2020 7:27 PM
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