Warning: Javascript must be enabled to use all the features on this page!


Page Loading - Please Wait...

Click to hideNews Bulletins

Streamflow Measurements for the Nation

! Streamflow measurement pages will be decommissioned in early 2026. Please find the modernized pages in WDFN that suit you best. Learn more about our modernization plans and timeline and new pages.

USGS 372744122253201 ARROYO LEON A HALF MOON BAY CA
San Mateo County, California
Hydrologic Unit Code 18050006
Latitude  37°27'44", Longitude 122°25'32" NAD27
Drainage area 8.52  square miles
Output formats
HTML table with channel data
HTML table without channel data
Tab-separated data with channel data
Tab-separated data without channel data
Graph of data
Reselect output format
Meas.
Number		   Date       Time Time
Datum		 Measurement
Used?		   Who Measuring
Agency		 Stream
flow
(ft3/s)		 Gage
Height
(ft)		 GH
Change
(ft)		 Meas.
Duration
(hr)		 Meas.
Rated		   Control Flow
Adjust.
Code 		 Channel
Number		 Channel
Name		 Meas.
type 		 Stream
flow
method 		 Velocity
method 		 Channel
flow
(ft3/s)		 Channel
width
(ft)		 Channel
area
(ft2)		 Channel
vel.
(ft/s)		 Channel
stability 		 Channel
material 		 Channel
evenness 		 Long.
vel.
desc. 		 Horz.
vel.
desc. 		 Vert.
vel.
desc. 		 Channel
loc.
code 		 Channel
loc.
dist.(ft)
311993-04-26 17:40PDTYesGMKUSGS0.03 GoodClearNONE1Imported Channel 1OTHRQFLUM 0.03 UNSPUNSPUNSPunknUNSPUNSPUNSP
301993-03-18 09:09PSTYesCTPUSGS6.37 0.000.70GoodDebrisHeavyNONE1Imported Channel 1WADEunspeunkno6.379.506.590.97UNSPUNSPUNSPunknUNSPUNSPUNSP
291993-02-23 07:59PSTYesCTPUSGS58.6 -0.050.90GoodDebrisHeavyNONE1Imported Channel 1WADEunspeunkno58.620.520.92.80UNSPUNSPUNSPunknUNSPUNSPUNSP
281993-01-19 14:36PSTYesCTPUSGS37.8 0.000.50GoodDebrisHeavyNONE1Imported Channel 1WADEunspeunkno37.811.213.02.91UNSPUNSPUNSPunknUNSPUNSPUNSP
271992-12-14 15:05PSTYesCTPUSGS0.86 0.000.50FairDebrisHeavyNONE1Imported Channel 1WADEunspeunkno0.866.602.430.35UNSPUNSPUNSPunknUNSPUNSPUNSP
261992-11-18 16:45PSTYesCTPUSGS0.03 0.000.30ExcellentDebrisLightNONE1Imported Channel 1OTHRQFLUM 0.03 UNSPUNSPUNSPunknUNSPUNSPUNSP
251992-04-15 09:32PDTYesCTPUSGS0.08 0.000.30ExcellentClearNONE1Imported Channel 1OTHRQFLUM 0.08 UNSPUNSPUNSPunknUNSPUNSPUNSP
241992-03-10 16:15PSTYesCTPUSGS7.91 0.000.60GoodDebrisHeavyNONE1Imported Channel 1WADEunspeunkno7.918.006.231.27UNSPUNSPUNSPunknUNSPUNSPUNSP
231992-02-14 12:45PSTYesJJGUSGS1122.500.400.50PoorDebrisModerateNONE1Imported Channel 1WADEunspeunkno11221.039.32.85UNSPUNSPUNSPunknUNSPUNSPUNSP
221992-01-15 09:05PSTYesCTPUSGS0.76 0.000.60FairClearNONE1Imported Channel 1WADEunspeunkno0.764.201.570.48UNSPUNSPUNSPunknUNSPUNSPUNSP
211991-12-10 08:30PSTYesCTPUSGS0.07 0.000.60GoodDebrisLightNONE1Imported Channel 1OTHRQFLUM 0.07 UNSPUNSPUNSPunknUNSPUNSPUNSP
201991-05-15 07:55PDTYesCTPUSGS0.38 0.000.70FairClearNONE1Imported Channel 1WADEunspeunkno0.384.801.400.27UNSPUNSPUNSPunknUNSPUNSPUNSP
191991-04-17 11:30PDTYesCTPUSGS0.06 0.000.30PoorClearNONE1Imported Channel 1WADEunspeunkno0.061.500.240.25UNSPUNSPUNSPunknUNSPUNSPUNSP
181991-03-29 14:55PSTYesLFTUSGS13.2 0.000.50GoodClearNONE1Imported Channel 1WADEunspeunkno13.29.509.691.36UNSPUNSPUNSPunknUNSPUNSPUNSP
171991-02-14 11:20PSTYesWWAUSGS0.24 GoodClearNONE1Imported Channel 1OTHRQFLUM 0.24 UNSPUNSPUNSPunknUNSPUNSPUNSP
161991-01-17 10:30PSTYesWWAUSGS0.13 0.000.10ExcellentDebrisLightNONE1Imported Channel 1OTHRQFLUM 0.13 UNSPUNSPUNSPunknUNSPUNSPUNSP
151990-12-19 14:00PSTYesWWAUSGS0.34 0.000.30GoodClearNONE1Imported Channel 1OTHRQFLUM 0.34 UNSPUNSPUNSPunknUNSPUNSPUNSP
141990-06-13 18:30PDTYesWWAUSGS0.06 0.000.10GoodDebrisLightNONE1Imported Channel 1OTHRQFLUM 0.06 UNSPUNSPUNSPunknUNSPUNSPUNSP
131990-04-26 16:00PDTYesWWAUSGS0.89 0.000.20FairClearNONE1Imported Channel 1WADEunspeunkno0.894.001.060.84UNSPUNSPUNSPunknUNSPUNSPUNSP
12E1990-03-22 13:00PSTYesKLMUSGS0.01 UnspecifiedClearNONE1Imported Channel 1OTHRother 0.01 UNSPUNSPUNSPunknUNSPUNSPUNSP
111990-02-01 13:50PSTYesKLM/JJGUSGS1.22 0.000.40GoodClearNONE1Imported Channel 1WADEunspeunkno1.227.802.820.43UNSPUNSPUNSPunknUNSPUNSPUNSP
101989-12-20 14:55PSTYesKLMUSGS1.08 0.000.30Good NONE1Imported Channel 1WADEunspeunkno1.085.302.750.39UNSPUNSPUNSPunknUNSPUNSPUNSP
91989-11-15 13:05PSTYesERHUSGS1.51 0.000.50FairClearNONE1Imported Channel 1WADEunspeunkno1.519.702.640.57UNSPUNSPUNSPunknUNSPUNSPUNSP
81989-04-11 13:05PDTYesCTPUSGS0.16 0.000.30FairClearNONE1Imported Channel 1WADEunspeunkno0.162.050.500.32UNSPUNSPUNSPunknUNSPUNSPUNSP
71989-03-23 08:15PSTYesCTPUSGS10.4 0.000.50FairClearNONE1Imported Channel 1WADEunspeunkno10.410.49.511.09UNSPUNSPUNSPunknUNSPUNSPUNSP
61989-02-16 10:10PSTYesCTPUSGS1.38 0.000.50FairDebrisLightNONE1Imported Channel 1WADEunspeunkno1.385.602.060.67UNSPUNSPUNSPunknUNSPUNSPUNSP
51989-01-18 11:10PSTYesCTPUSGS0.80 0.000.50FairClearNONE1Imported Channel 1WADEunspeunkno0.804.001.040.77UNSPUNSPUNSPunknUNSPUNSPUNSP
41988-12-15 10:05PSTYesCTPUSGS0.02 0.000.10GoodClearNONE1Imported Channel 1OTHRQFLUM 0.02 UNSPUNSPUNSPunknUNSPUNSPUNSP
31988-02-19 11:15PSTYesWWA/ERHUSGS0.56 0.000.20FairClearNONE1Imported Channel 1WADEunspeunkno0.563.801.140.49UNSPUNSPUNSPunknUNSPUNSPUNSP
21988-01-06 09:40PSTYesWWAUSGS2.26 0.000.40GoodClearNONE1Imported Channel 1WADEunspeunkno2.267.803.740.60UNSPUNSPUNSPunknUNSPUNSPUNSP
11987-12-08 14:30PSTYesWWAUSGS4.53 0.000.50GoodClearNONE1Imported Channel 1WADEunspeunkno4.539.005.100.89UNSPUNSPUNSPunknUNSPUNSPUNSP