Big Sioux River above Flandreau

Highest listed crest 1,545.29 ftFlood stage 1,540.0 ft8 crests since 2011

The Big Sioux River above Flandreau crested at major flood stage 1 time among the 8 crests the National Weather Service lists from 2011 to 2025. The highest, 1,545.29 ft on September 13, 2019, was major flooding, 5.29 feet above flood stage. 13 other gauges on the Big Sioux River crested above flood stage within a week of it, 8 at their own highest listed crest.

The gauge

Highest listed crest: 1,545.29 ft; September 13, 2019
Flood stage: 1,540.0 ft; Major flooding from 1,545.0 ft
Crests at major: 1; 62nd of 155 gauges in South Dakota
Most recent flood crest: June 22, 2024; 1,540.03 ft, minor flooding
Location: Moody County; South Dakota
Identifiers: NWS BSFS2; No USGS station

Flood stages

The thresholds the National Weather Service uses for this gauge today, and how many listed crests reached each.

Flood categories, Big Sioux River above Flandreau

Action stage	1,537.0	2	Jul 3, 2025	The level at which the NWS or its partners begin to take action
Flood stage (minor)	1,540.0	2	Jun 22, 2024	Minimal or no property damage, but possibly some public threat
Moderate flood stage	1,542.0	3	Mar 23, 2019	Some inundation of structures and roads near the stream
Major flood stage	1,545.0	1	Sep 13, 2019	Extensive inundation of structures and roads

Every listed crest

8 crests from 2011 to 2025. Filled: at or above flood stage. Hover a crest for its date and stage.

Crests at or above flood stage, by decade

These are the crests the local National Weather Service office lists for the gauge: the highest on record and recent crests. Lesser floods between them may be missing, so counts by decade are a floor.
Categories use today's flood stages. Levees, dams and channel changes since a crest can make old and new stages not directly comparable.

Highest crests

Highest listed crests, Big Sioux River above Flandreau

1	Sep 13, 2019	1,545.29	+5.29	Major	—
2	Mar 25, 2011	1,543.85	+3.85	Moderate	—
3	Mar 23, 2019	1,543.53	+3.53	Moderate	—
4	Apr 25, 2018	1,542.40	+2.40	Moderate	—
5	Apr 9, 2023	1,540.72	+0.72	Minor	—
6	Jun 22, 2024	1,540.03	+0.03	Minor	—
7	Jul 3, 2025	1,538.38	−1.62	Action	—
8	Apr 1, 2020	1,538.33	−1.67	Action	—

The worst floods along the Big Sioux River

For this gauge's highest crests, the other gauges on the Big Sioux River that crested above flood stage within a week.

September 13, 2019: 1,545.29 ft here, major flooding

EganSD · Sep 12, 2019 · 1,524.20 ft · Major · its highest
TrentSD · Sep 13, 2019 · 1,501.42 ft · Major · its highest
Dell RapidsSD · Sep 13, 2019 · 1,490.00 ft · Major · its highest
BrandonSD · Sep 14, 2019 · 1,313.53 ft · Major · its highest
CantonSD · Sep 13, 2019 · 1,245.88 ft · Major
RichlandIA · Sep 17, 2019 · 1,123.51 ft · Major
HawardenSD · Sep 15, 2019 · 32.42 ft · Major
Sioux Falls I-90SD · Sep 14, 2019 · 18.91 ft · Major · its highest
Dell RapidsSD · Sep 13, 2019 · 16.70 ft · Major · its highest
FairviewSD · Sep 14, 2019 · 1,213.14 ft · Moderate · its highest

March 25, 2011: 1,543.85 ft here, moderate flooding

AkronIA · Mar 26, 2011 · 20.39 ft · Major
Dell RapidsSD · Mar 24, 2011 · 15.63 ft · Major
WatertownSD · Mar 23, 2011 · 12.56 ft · Major
Sioux Falls N. Cliff AvenueSD · Mar 25, 2011 · 21.53 ft · Moderate
BrookingsSD · Mar 24, 2011 · 13.33 ft · Moderate
CastlewoodSD · Mar 23, 2011 · 12.29 ft · Moderate
BruceSD · Mar 28, 2011 · 12.16 ft · Moderate · its highest
WatertownSD · Mar 23, 2011 · 10.30 ft · Minor

March 23, 2019: 1,543.53 ft here, moderate flooding

EganSD · Mar 23, 2019 · 1,522.48 ft · Major
TrentSD · Mar 24, 2019 · 1,500.00 ft · Major
Dell RapidsSD · Mar 24, 2019 · 1,487.53 ft · Major
RichlandIA · Mar 16, 2019 · 1,124.50 ft · Major
JeffersonIA · Mar 17, 2019 · 40.42 ft · Major
AkronIA · Mar 16, 2019 · 23.94 ft · Major
Dell RapidsSD · Mar 24, 2019 · 15.69 ft · Major
WatertownSD · Mar 28, 2019 · 12.31 ft · Major
EstellineSD · Mar 28, 2019 · 1,646.90 ft · Moderate
Sioux Falls N. Cliff AvenueSD · Mar 26, 2019 · 22.06 ft · Moderate

Gauges on the Big Sioux River

Flood gauges sharing the river's name, linked within 80 miles of one another.

Flood gauges on the Big Sioux River

Canton	SD	1,235.0	1,248.35 ft, Jun 22, 2024	3
Dell Rapids	SD	1,481.0	1,490.00 ft, Sep 13, 2019	2
Flandreau this gauge	SD	1,540.0	1,545.29 ft, Sep 13, 2019	1
Hawarden	SD	20.5	39.92 ft, Jun 22, 2024	4
Akron	IA	16.0	27.35 ft, Jun 22, 2024	24
Fairview	SD	1,202.0	1,213.14 ft, Sep 14, 2019	0
Lake Kampeska	SD	21.0	22.40 ft, Mar 15, 2010	0
Lake Poinsett Inlet/Outlet	SD	1,654.0	1,657.60 ft, Apr 5, 2011	2
Sioux City	SD	32.0	44.90 ft, Jun 23, 2024	1
Sioux Falls I-90	SD	12.0	18.91 ft, Sep 14, 2019	1
Sioux Falls N. Cliff Avenue	SD	16.0	26.08 ft, Sep 14, 2019	0
Sioux Falls Western Avenue	SD	8.0	16.90 ft, Mar 14, 2019	4
Trent	SD	1,495.0	1,501.42 ft, Sep 13, 2019	2
Watertown Broadway Avenue	SD	10.5	13.67 ft, Apr 6, 1997	1
Watertown Sioux Conifer Road	SD	9.0	11.18 ft, Apr 13, 2023	0
Watertown	SD	11.0	13.13 ft, Apr 2, 1997	5
Brandon	SD	1,304.0	1,313.53 ft, Sep 14, 2019	2
Brookings	SD	9.0	14.77 ft, Apr 9, 1969	0
Bruce	SD	8.0	12.16 ft, Mar 28, 2011	0
Castlewood	SD	9.0	13.19 ft, Apr 7, 1997	0
Dell Rapids	SD	12.0	16.70 ft, Sep 13, 2019	10
Egan	SD	1,516.5	1,524.20 ft, Sep 12, 2019	2
Estelline	SD	1,644.0	1,647.03 ft, Jun 30, 2025	0
Florence	SD	8.0	9.70 ft, Apr 13, 2023	6
Jefferson	IA	31.0	44.50 ft, Jun 24, 2024	2
Richland	IA	1,117.0	1,128.70 ft, Jun 23, 2024	5
Watertown	SD	10.0	12.33 ft, Apr 7, 2001	2

Other gauges in Moody County

Flood gauges in Moody County

Trent	1,495.0	1,501.42 ft, Sep 13, 2019	2
Brookings	9.0	14.77 ft, Apr 9, 1969	0
Egan	1,516.5	1,524.20 ft, Sep 12, 2019	2
Flandreau	9.0	14.00 ft, Sep 12, 2019	0
Chester	7.0	7.45 ft, Jul 10, 2011	0

Moody County: every hazard · River floods across the country · South Dakota

NOAA National Water Prediction Service, gauge BSFS2, retrieved October 30, 2026. Stages in feet on the gauge's own datum, not elevation. Crests are as the National Weather Service lists them; preliminary values may be revised.