months, stage and discharge may be affected by ice in the
channel. Data values reported on these pages may be
significantly higher or lower than the actual streamflow.
Adjustments to the data will be done after detailed analyses.
Ice affected values identified on graphs (•) may be viewed by choosing the table
output format. If you have questions about these values,
please contact the
Idaho Water Data Maintainer.
LOCATION.--Lat 47° 42'11", long 116° 58'40"
(NAD83), in SW1/4 SW1/4 SW1/4 sec.4, T.50 N., R.5 W., Kootenai
County, Post Falls quad., Hydrologic Unit 17010305, on right bank 1
mi downstream from powerplant of Avista Utilities, 1.5 mi southwest
of Post Falls, and at mile 100.7.
DRAINAGE AREA.--3,830 mi2, of which about 122
mi2 in the vicinity of Hayden Lake is noncontributing.
PERIOD OF RECORD.--October 1912 to current year (prior to January
1913, monthly discharge only, published in WSP 870 and 1736). Prior
to October 1949, published as "at Post Falls."
REVISED RECORDS.--WDR-US-2010: Drainage area.
GAGE.--Water-stage recorder. Datum of gage is 2,050 ft, referred
to originally accepted elevation of 2,157.40 ft for the U.S.
Geological Survey bench mark in southeast corner of Idaho First
National Bank Building (see WSP 882). Datum of gage based on NGVD of
1929, supplementary adjustment of 1947, is 2,047.00 ft. Datum of gage
using NAVD88 is 2,050.885 ft.
Jan. 1, 1913 to Nov. 21, 1920, nonrecording gage, and Nov. 22,
1920 to Sept. 15, 1934, recording gage 0.6 mi upstream. From Sept.
16, 1934 to Nov. 15, 1949, recording gage 0.8 mi upstream. From Nov.
16, 1949, at present site. Datum of all gages prior to Sept. 30,
1964, 50 ft lower.
REMARKS.--Flow regulated by dam at Post Falls and affected by
storage in Coeur d'Alene Lake (sta 12415500).
EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 50,100
ft3/s, when recorder was not operating, Dec. 25, 1933,
(determined from unpublished records collected by Washington Water
Power Co. for station at Liberty Bridge); minimum discharge, 65
ft3/s July 25, 30, 1973; minimum gage height, 4.68 ft,
July 20, 21, 1977.