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Hydrograph River at a Glance Download
Saint Vrain Creek at Hygiene Stage (ft)Colorado Division of Water ResourcesSVCC2(plotting HGIRG) Graph Created (8:30PM May 26, 2024)Flood Stage is 9.5 ft
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Tabular Data (UTC)
Tabular Data (MDT)
XML Data
RSS Files
Datum: NGVD29
NOTE: Forecasts for the Saint Vrain Creek at Hygiene are issued as needed during times of high water, but are not routinely available.
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Upstream Gauge - at Lyons Upstream Gauge Downstream Gauge Downstream Gauge - below Longmont
Flood Categories (in feet)
Major Flood Stage: 12.5
Moderate Flood Stage: 11
Flood Stage: 9.5
Action Stage: 8.5
Low Stage (in feet): -9999

Historic Crests
(1) 6.71 ft on 05/04/2015
(2) 5.74 ft on 06/01/2014
(3) 5.05 ft on 06/07/2021
(4) 5.02 ft on 05/27/2017
(5) 4.86 ft on 07/02/2019
(6) 4.59 ft on 05/29/2018
(7) 4.55 ft on 06/13/2016
(8) 3.05 ft on 06/06/2020

(P): Preliminary values subject to further review.

Recent Crests
(1) 5.05 ft on 06/07/2021
(2) 3.05 ft on 06/06/2020
(3) 4.86 ft on 07/02/2019
(4) 4.59 ft on 05/29/2018
(5) 5.02 ft on 05/27/2017
(6) 4.55 ft on 06/13/2016
(7) 6.71 ft on 05/04/2015
(8) 5.74 ft on 06/01/2014

(P): Preliminary values subject to further review.

Low Water Records
Currently none available.

For more information on your flood risk go to

Zoom Level:11
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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.
Flood Impacts & Photos Collapse
If you notice any errors in the below information, please contact our Webmaster
13 Extensive, life-threatening flooding occurs with roads crossing Saint Vrain Creek likely impassable.
12.5 Widespread, major flooding occurs with many roads, homes and businesses impacted. This level represents a flood that has a 2-percent chance of being equaled or exceeded in any given year. For more information click here.
11 Houses and businesses along the creek in Longmont flood.
10.5 Water overtops driveways and parking lots near Main Street in Longmont.
9.7 Saint Vrain Creek is at full capacity through Longmont.
9.5 Structures in low lying areas along the creek in Longmont begin to flood.
8.5 There is lowland and meadow flooding along the creek in western Longmont.
(1) Looking Upstream
(2) Looking Downstream
About This Location Collapse

Latitude: 40.177500° N, Longitude: 105.178100° W, Horizontal Datum: NAD27

River Stage
Reference Frame
Gauge Height Flood Stage Uses
NWS stage 0 ft 9.5 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 5056.83 5066.33 Older USGS topographic maps, NGVD29 benchmarks
MSL Not Available Not Available Older USGS topographic maps, MSL benchmarks
Other Not Available Not Available  
Additional Information Collapse
Observations provided by the Colorado Division of Water Resources
Resources Collapse
Hydrologic Resources Additional Resources
Collaborative Agencies Collapse
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.
NWS Information
National Weather Service
Denver/Boulder Weather Forecast Office
325 Broadway
Boulder, CO 80305-3328
(303) 494-4221
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Page last modified: 30-Oct-2020 4:08 PM
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